Facial Rejuvenation with Fillers

Wm. Philip Werschler, MD

In this presentation, Dr Werschler provides an overview of the fillers currently available on the market by class and by product, and how they can be utilized in clinical practice along with some key takeaway points for clinicians.

How did we get here today?

Beginning in 1981, bovine collagen was introduced to the US marketplace. As people began to get their winkles and fold augmented to look younger they discovered that,unfortunately, the duration of collagen was only three months or so, thus the market for collagen injections never grew to meet expectations   And it was subsequently withdrawn from the market. In  December, 2003, the US FDA approved  Restylane (Hyaluronic Acid), whichrevolutionized the dermal filler market . With a duration  of correction to 6+ months, no pre-treatment skin testing, ease of use, room temperature storage and modest cost, there was now a viable product for the emerging, if nascent, dermal filler market.

PMMA (Radiesse), a novel “next-generation” filler was approved in 2006 by the FDA for the correction of wrinkles and folds (such as Nasolabial Folds), and for the correction of HIV-associated lipoatrophy. Unique and distinctly different in its’ mechanism of action, Radiesse is termed a “stimulatory” or “collagen-stimulator” product.  This differs from the previous generation “replacement” space occupying materials collagen and hyaluronic acid.  With the addition of collagen stimulation, the duration of effect of Radiesse was extended to 9-18 months.

On the same day that Radiesse was approved, the FDA also approved the first and only “permanent” dermal filler, Artefill (collagen + PMMA).  Artefill consists of bovine collagen in combination with polymethmethacrylate spheres.   As these spheres are non-biodegradable, they represent a permanent placement into the tissue.  Well tolerated with an excellent safety profile, Artefill does require pre-treatment skin testing because of the bovine collagen present. Special handling includes refrigeration, and collagen stimulation gradually anchors the PMMA spheres into place typically after 2-3 treatments.

In 2007/2008 Hyaluronic Acid plus manufacturer added lidocaine was FDA approved for the hyaluronic acids, Juvederm, Restylane and Perlane. Similarly, the FDA approved the mixing of lidocaine and Radiesse by the injector at the time of use.  These approvals resulted in greater patient comfort during injection and further expanded the dermal filler marketplace. Stabilized Porcine Collagen came onto the market briefly during this time, however due to problems with patient tolerance and complications, the manufacturer withdrew the product and it is no longer available.

In 2009, the FDA approved Sculptra, poly L lactic acid, for aesthetic use (it received FDA approval in 2004 for HIV associated facial lipoatrophy).  A pure collagen stimulator, Sculptra is technically not a dermal filler, however it is best thought of in this category.  Sculptra is routinely mixed with lidocaine and sterile water for injection, requires 3-5 injections sessions to gradually grow new collagen leading to the clinical effect developing over a period of  3-6 months.  Duration is a 2+ years effect based on extensive clinical trials and experience.

More recently, an advanced technology hyaluronic acid  (Belotero) and  an autologous cultured dermal fibroblast  (LAVIV)  were approved. Belotero is a “cohesive polydensified matrix” hyaluronic acid which possess different tissue integration properties than previous generation products.  The net clinical result is that the product may be injected more superficially than other HAs without risk of the Tindall or Rayleigh effect tinting the skin blue.

Laviv, like Sculptra, is technically not a dermal filler but rather a tissue stimulator that upregulates native collagen production.  This process includes harvesting tissue from the patient (post-auricular) and sending it to a processing laboratory which then amplifies the cell count and returns a viable culture for re-injection. The first FDA approved tissue therapy for aesthetics, Laviv presents a multitude of intriguing possibilities in the future.

Ever since fillers first came onto the market, experts have been trying to develop a methodology  to differentiate them and there are many ways  to do so:

  • Chemical components
  • Duration of action
  • Natural/Synthetic
  • MOA
    • Replacement Filler or Bio-Stimulatory/collagen stimulator

Looking at fillers by their MOA has seemed to work very well when differentiating the products.

Dermatologists should be aware that fillers exist in two primary categories:

  • Volume Replacement
  • Collagen Stimulation

When you use the above descriptive methodology, you can see that collagen and hyaluronic acids are replacement fillers and PLLA and LAVIV are bio-stimulatory. And notably, CaHA ad PMMA are blends of both MOAs.

There are many ways to categorize fillers within a class.

Volume Replacement

Hyaluronic Acid

HAs have a very simple chemical structure and is identical in all species and tissues; thus it is non-immunogenic. It is found in all vertebrates and synthesized by some bacteria. The identical structure of HA from all sources makes it an ideal substance for use as a biomaterial in health and medicine.  HAs are highly hydrophilic; therefore, they absorb water, i.e., their principal method of giving a volumizing effect. They are also rapidly metabolized in vivo.

Gel Mass Sizing

In addition to crosslinking, manufacturers use other techniques to improve HA filler properties.  For example, Medicis uses a process that creates specific sizes and shapes to form granular consistency gels Restylane® and Perlane®.

In creating the JUVÉDERM® family of products, Allergan uses Hylacross™ Technology to create random sizes and shapes that form a smooth cohesive gel. While the new to market Beletero uses yet another technology (CPM) to achieve unique properties.

Does this make a difference clinically? It depends on who you ask…

Hyaluronic acids can be used virtually everywhere for anything and everything and they are the most versatile of all of the filler products. These fillers may be ideal for novice patients because they have an  “eraser” (hyaluronidase) which can be injected to make the product dissolve, if so desired for either aesthetic effect or for treatment of necrosis. . This is a unique feature of  this category.

New Approaches to Fillers: Pure Neocollagenesis


The question is…Are these products really stimulators? Dr Werschler believes, they are for lack of a better descriptive term. Through a variety of mechanisms of action, they stimulate fibroblasts to make collagen.

PLLA was first approved for HIV-related facial lipoatrophy in the United Sates in 2004 and the aesthetic approval was received in 2009.  It is the only approved pure collagen stimulator currently available in the US; therefore, it is considered “stimulatory” and “biodegradable” in classification. PLLA is indicated for the correction of nasolabial folds. Of note, Dermik aesthetics, a division of sanofi-aventis, recently sold the product to Valeant Pharmaceuticals Intl. based in Canada.

What is the composition of PLLA?

  • Poly-L-lactic acid
  • Sodium  carboxymethylcellulose (CMC)
  • Non-pyrogenic mannitol
  • Sterile water (added) for injection (USP)
  • Lidocaine (optional—most dermatologists and plastic surgeons add lidocaine for patient comfort)

Sculptra™ is composed of microparticles of PLLA, a biocompatible, biodegradable, synthetic polymer from the alpha-hydroxy-acid family.  It is derived from natural components, it is a crystalline, amorphous mixture with microparticles averaging 40 to 63 μm in size. The slow resorption of PLLA after implantation is due to the high molecular weight (140,000 Daltons) of the polymer and the irregular crystalline shape of the microparticles.

Lactic acid can be converted through polymerization to a variety of polymers, including poly-L-lactic acid. Many of these polymers, including polylactic acid, have been used for many years in medical devices and sutures, including absorbable sealants, flow restrictors, fixation systems, suture anchors/absorbable sutures, fixation screws, and tissue regeneration.

The slide below is very important looking at skin thickness of HIV patients using ultrasound. The plot includes the data points for all patients in the VEGA study. All patients experienced increases in skin thickness in the treatment area (minimum increase of 2.2 mm noted at Week 8 visit).

Statistically significant increases above baseline values of mean skin thickness were noted at all time points (Weeks 8, 24, 48, 72, and 96) during the study.  This slide demonstrates the product’s MOA of growing collagen and therefore, thickening the dermis.

The slide below demonstrates marked improvement in wrinkle assessment score (WAS) utilizing Sculptra®Aesthetic at all time points through 25 months.

Each Wrinkle Assessment Score, or WAS, at the time points shown represented the median of 3 investigator’s scores, and each of the investigator’s evaluations represented an average of scores for the left and right nasolabial folds.1

In the WAS coding system, 0 equals no wrinkles; 1 refers to a just-perceptible wrinkle; 2 indicates a shallow wrinkle; 3, a moderately deep wrinkle; 4, a deep wrinkle with well-defined edges; and 5, a very deep wrinkle or redundant fold.2

Investigator evaluations throughout the study confirmed that improvements in facial appearance with Sculptra®Aesthetic achieved improvement in WAS. As this graph shows, improvements from baseline at 25 months proved to be consistent, progressive, and statistically significant at each time point (P<0.001): 100% of patients improved at week 3; 88.7% at month 13; and 86.3% at month 25.1

How long does it last? Maybe two to three years. It is important to remember that it is difficult to establish exact duration of the product because of one’s natural course of aging.


1. Data on file, Dermik Laboratories.

2. Sculptra®Aesthetic Prescribing Information, Dermik Laboratories; 2009.

Where is it used?

Poly-L-lactic acid treatment primarily to add volume, and as such is used to thicken dermis and to stimulate collagen growth in the pre-periosteal plane.  Placement may include the temporal hollows, across the zygomata, in the mid face, nasolabial folds, labiomental sulcus, prejowl sulcus, mandibular sweep, angle and for genioplasty.  Sculptra is not recommended for use in areas of concentric movement such as the lips and eyelids.

Personalized Dermal Technology

LaViv is an innovative technology to isolate, purify, and regenerate a patient’s own fibroblast cells for re-injection.

Fibroblast cells produce collagen and play key role in the continued health of skin. Collagen provides firmness and structure to the skin and is essential in supporting the dermis.. As skin ages, fibroblast cells decrease and the collagen matrix that provide the skin its structure breaks down.

This is a way to restore the equilibrium.  LaViv is the first autologous cell therapy for use in aesthetics filed with the FDA. There is strict release testing on each clinical lot to ensure performance and safety including:

  • Collagen content testing results must achieve specification for each prepped injection, indicating cells are biologically active and produce collagen
  • Cell suspension must consist of at least 98% fibroblasts prior to release
  • Cells in suspension must achieve a viability level of at least 85%
The LaViv Treatment Process:
  • Extraction
    • A small cell sample (ideally three small skin bioposies) is removed behind the ear from a small skin punch biopsy with the use of local anesthetics
  • Purification & Culturing
    • A proprietary manufacturing process multiplies fibroblasts from the sample into tens of millions of new cells in approximately 3 months
    • Fibroblasts are tested by quality control and released by quality assurance prior to shipment
    • Cells are frozen for use in potentially multiple treatment sessions
  • Injection
    • Recommended regimen is three treatment sessions at 3-6 week intervals
    • In clinical trials, a statistically significant difference between LAVIV™ and placebo was seen by the time of the third treatment

As far as side effects with LaViv, there is an increase in erythema, swelling, pain, and a slight urticarial-like response.

New Approaches to Fillers: Volume Replacement + NeoCollagenesis

Calcium Hydroxylapatite (CaHa)-Radiesse

CaHa is best used for facial contouring. It’s mechanism of action is to serve as a filler material initially (particles + gel) then provide long term benefit through natural collagen integration in and around the particles. The result is a long lasting, but not permanent correction augmentation that feels like the patient’s own tissue.

The advantages of Radiesse  include immediate site-specific correction in one to two sessions and strong structural tissue support withno Tyndall effect. CaHa is malleable up to two weeks and has a long duration of nine to 18 months. No pretreatment testing is required, it is also cost-effective and does not migrate or obscure radiographic studies and it doesn’t ossify in the skin.

Radiesse received approval in the United Sates in 2006 for both HIV and aesthetic use and is the only approved biodegradable dual collagen stimulator and replacement filler currently available in the US. When utilizing Radiesse, no skin or allergy testing is needed and there is no special handling. The product is available in 0.3, 0.8 and 1.5 mL and recently approved 3.0 mL syringes through Merz Aesthetics.

Where is it used?

CaHA is used most everywhere; however, it is not ideally used in the lips or the eyelids. Some people do use the product in those areas; however, Dr Werschler does not recommend it.

PMMA Dermal Filler-Artefill

Artefill was approved in the United Sates in 2006 and is the only approved PMMA-enhanced dermal filler currently available in the US. It is indicated for the correction of nasolabial folds. Suneva Medical acquired (ARTES) Artefill in 2009 and is currently manufacturing, selling, and distributing Artefill in the US.

The slide above depicts that initially your percent implant volume is mostly collagen. The bovine collagen goes away rather quickly and you have the PMMA microspheres that stay in the skin. (Of note, PMMA is similar to Lucite, in that, it is a non-biodegrable substance that will remain in the skin forever.) The remaining PMMA  elicits this fibroplasia-like response, the autologous collagen is produced by fibroblasts, it surrounds the microspheres, anchors them in place and that is what gives patients the long-term effect.



There is a long-term extended duration of action which is what one would expect.


Injectables are:

    • They can enhance natural features
    • They can rejuvenate fading youth
    • They can restore aged, facial features
    • They can even improve natural beauty
    • Each product has features that result in certain benefits in clinical use
    • Put another way, they are not all alike!
 Clinical Pearls
  • Use filling agents appropriate to the requirements of the job
  • Not all products are created equal – understand the differences!
  • Some areas are more difficult to correct than others  (e.g. lips and tear troughs) so master the basic indications first such as NLF
  • Evaluate and approach filling from a multi-step progression:
    • Volume, shape, contour, wrinkle, line and crinkle filling.
    • Product duration claims are a slippery slope- be careful with those and be conservative with your ranges. Underpromise and over deliver.




The Science of Toxins Part 3

Michael Gold, MD

Dermatologists should be aware that the global medical aesthetic market is expected to grow 10.8% per year between 2010 an 2015 and many other companies are joining the toxin “band-wagon”.

Products Under Development/Currently Approved in Other Countries
  • Medy-Tox – Neuronox (South American and Korea)
  • Siax – Neuronox (Colombia)
  • ChinaTox –Lanzhou Biological Products Institute, Nanfeng Medical  Science and Tech co.
  • Lantox (South America)

Mentor is currently developing a product called PurTox, which is about one year away from filing with the FDA for approval. There are also several products currently available in Asia and South America. Dermatologist should recognize that in some instances where non-approved Botox formulations were used in the United States, patients required hospitalization due to paralysis and physicians were subject to major sanctions, fines, etc.


It is important that practitioners use branded products from legitimate companies that are either FDA approved in the US or CE marked in Europe, or received regulatory approvals in your country.  There are various unbranded products available on the internet; however, clinicians should use caution with regard to the use of these products due to safety and efficacy issues.






Botulinum Toxin 2012: Applying the Data Into Clinical Practice Part 2

Joel Cohen, MD


Upper Face: “The Big 3”

Botox, Dysport, and Xeomin are all FDA approved for glabellar lines. The products are also used for the forehead and crow’s feet.


Dermatologists should be cautious of the dangers associated with delivering fillers and toxins simultaneously.


Data suggest that higher botulinum toxin type A doses resulted in greater efficacy and longer duration of the effect. In 2008, experts developed a consensus with regards to how to best achieve an optimal, relaxed and natural outcome using botulinum toxin type A. This resulted in basically cutting the forehead doses in half.

Dermatologists should also understand gender differences that exist in upper face musculature. In a 1998 cadaver study by Dr Macdonald, et al, males were shown to have greater corrugator thickness at both the medial canthus and mid-pupil regions versus females. An understanding of these anatomic differences can facilitate proper injection technique.


Dr. Cohen indicates that he does not think physicians should be desperately trying to find the right conversion ratio between products. He feels that the reality is that each of these products is it’s own neuromodulator. As such, he indicates, that if we decide to use that specific neuromodulator, then we should know that neuromodulator independently—and thus how to specifically use that product.


Patient satisfaction is a key aspect of facial aesthetics. Various studies have looked at patient reported outcomes among the products available; however, it is often difficult to compare the results.


Across the board, looking at the glabellar lines, the duration of botulinum toxin type A is about four months.  Data has also demonstrated that patients tend to have a cumulative effect; in that, the efficacy is stretched out over a longer period of time.


Drs. Richard Glogau, Fred Brandt and others have begun to research topically applied botulinum toxin type A for the treatment of primary axillary hyperhidrosis as well as lateral canthal rhytid studies. Results have shown that topically applied BTX-A appears to be safe and effective.

Revance, a California-based company, has developed a proprietary platform that enables transcutaneous flux. The Revance technology works by employing two complementary and distinct pathways that are both present in human skin:

The first pathway is energy independent and therefore can occur in non-living cells. like the stratum corneum.  It could also occur in living cells. The second pathway is energy dependent and only occurs across living cells.


Myoscience is currently investigating a hand-held cryotherapy medical device for the treatment of facial wrinkles between the brow, forehead lines and crow’s feet. It has shown promising results in difficult patients, i.e., complete treatment of dynamic horizontal forehead lines, constant brow position, immediate onset, and it proves to be a potentially new option for toxin-averse patients.  The device uses a 27-30-gauge needle placed near motor nerves that innervate frontalis muscle.


It is important that dermatologists convey the message that botulinum toxin type A has been studied and BTX injections can be beneficial for patients who want to delay the outward appearance of aging, for patients who believe their faces are not communicating their emotions properly and/or for patients who simply want to look their best.



Botulinum Toxin 2012: Where are we now? Part 1

Joel Cohen, MD

In this presentation, Dr Cohen reviews the use of botulinum toxins in clinical practice. He reviews the three Type A toxins such as Botox, Dysport, and Xeomin.

Science and Data To Be Considered

It is important that clinicians understand the molecular structure of Botulinum neurotoxin type A.

The core neurotoxin protein in all agents used clinically is 150kD BoNT/A.  Botox and Dysport both have accessory proteins that surround the core neurotoxin, while Xeomin lacks accessory proteins.

Botulinum toxin Type A works via chemodenervation, in that the internalized toxin binds to the SNAP-25 target protein and then blocks the exocytosis of acetylcholine into the synaptic cleft following a neural impulse.  This effectively denervates the segment of muscle supplied by the affected cholinergic nerve terminal.

Differentiating Botulinum Toxins

Regulatory agencies worldwide have recognized that these products are not interchangeable. The units of biologic activity in each available product cannot be compared or converted into the units of any of the other available products, nor can the doses or preparations be interchanged.


Dermatologists should be aware that botulinum toxin itself could be immunogenic. The protein added to stabilize the product also has immunogenic properties. If antibodies occur, the question is whether or not they are neutralizing “critical domain” antibodies or non-neutralizing “non-critical domain” antibodies.  Antibody detection can measured through two tests. The Mouse Protection assay is the most widely used with the highest specificity. The patient’s serum is taken and given to a mouse. The mice are then given a lethal dose of BTX-A. If the mouse lives, the patient has antibody; in most cases the mouse would die. The rapid immunoassays (ELISA, W. BLOT) have a lower specificity and a lack of correlation between detected abs and clinical resistance.

Various data and studies suggest that overall, few patients may develop antibodies; however, they if they do develop antibody, they seem to continue to respond to the products.

Challenging Psoriasis Cases 2012

Bruce Strober, MD, PhD


Case Study 1 – IL-12/23 Inhibitors
  • 54 year-old man
  • Severe psoriasis affecting 25% BSA, PGA = 3
  • No psoriatic arthritis
  • Failure to respond to:
    • Methotrexate 20 mg weekly for 12 weeks
    • Etanercept (primary failure)
    • Adalimumab (primary failure)
    • Infliximab (initial response, with subsequent failure)
    • History of:
      • Hypertension
      • Hypercholesterolemia
      • Hypertriglyceridemia
      • Obese, 120 kg, BMI = 33

[poll id=”2″]

There is concern for this patient because he is at a relatively high risk for cardiovascular disease. However, he has not responded to various treatments and needs therapy in order to function.

      • How do you discuss ustekinumab with this patient prior to initiation of therapy?

Discuss his risks of cardiovascular disease and conduct a benefit/risk assessment of ustekinumab prior to starting therapy

[poll id=”3″]
[poll id=”4″]
[poll id=”5″]

Case Study 2- Topical Therapy
      • 42 year-old man
      • Psoriasis affecting 4% of BSA
        • Inverse pattern
          • Inguinal
          • Intergluteal and perianal
      • Refractory to alclometasone dipropionate cream
      • No psoriatic arthritis

[poll id=”6″]

Case Study 3- Scalp Psoriasis
      • 22 year-old woman
      • Severe scalp psoriasis, affects 50% of scalp surface area, failed:
        • OTC preparations (T-gel)
        • Fluocinolone acetonide topical scalp oil 0.01%
        • Clobetasol shampoo, solution and foam

[poll id=”7″]

Case Study 4- Refractory Local Psoriasis in a Patient on Biologic Therapy
      • 46 year-old man with > 20 years of severe psoriasis and psoriatic arthritis
      • Baseline: 20% BSA, PGA = 4
      • Currently managed effectively with:
        • TNF-inhibitor in combination with MTX 10 mg per week
        • BSA currently 4%, with residual disease on the elbows and lower extremities
        • Refractory to topical class 1 corticosteroids

[poll id=”8″]

Case Study 5- Latent TB
      • 52 year-old man with 40% BSA
      • Active psoriatic arthritis
      • Only treated with UV Phototherapy and topicals, neither of which is effective
      • PPD is positive to 12 mm induration
      • Chest X-ray shows no infiltrate and chest CT is normal

What if this patient had previous BCG vaccination?

      • Verify latent TB status with Quantiferon Gold test

What are your steps to starting therapy for this patient?

      • Quantiferon Gold test
      • If positive, treat with a full course of latent TB infection prophylaxis prior to initiation of immunosuppressive/immunomodulatory therapy. Therapy for psoriasis may be begun 1 month into treatment for latent TB.
      • Discuss various treatment options review the benefits/risks


How do you follow/monitor a patient with treated latent TB while on a TNF-inhibitor?

      • Be vigilant of signs and symptoms of TB

[poll id=”9″]

[poll id=”10″]

Case Study 6- New Onset Psoriasis
      • 53 year-old woman
      • Crohn’s disease on TNF-inhibiting antibody with gastrointestinal disease is well-controlled
      • Develops palmoplantar pustular dermatitis

Could the psoriasis have been induced by the TNF-inhibitor?

[poll id=”11″]



B-Cell Targeted Therapy in Autoimmunity

Written by: Judy Seraphine Based Upon a Presentation Delivered by Arthur Kavanaugh, MD at the 2012 Maui Derm 


B cells may play a prominent role in a number of autoimmune diseases, including rheumatoid arthritis, systemic lupus erythematosus, pemphigus/pemphigoid, vasculitis, and many others. The mechanisms by which B cells may play a role in autoimmunity include autoantibody secretion, modulation of immune/inflammatory reactions via ctyokines and other mediators, antigen presentation / co-stimulation of T cells, and  lymphoid organogenesis in target organs. The activity of B cells in autoimmunity represents a loss of immunologic tolerance. The targeting of B cells specifically is now possible; the first approved agent being the anti-CD20 monoclonal antibody, rituximab. Clinicians should be aware that B cells may be targeted in many other ways and the results on the efficacy and safety of these approaches are forthcoming. Safety issues related to targeting of B cells may be both agent-specific as well as target-specific and the major concerns include the potentially increased risk of infections.

B Cells – Autoimmunity: History

Paul Ehrlich, the “Grandfather” of autoimmunity, first studied B cells in autoimmunity via histologic staining and the identification of blood cells. More importantly, Dr Ehrlich came up with the side chain theory, i.e., a specific receptor for a counter-receptor on a type of cell. This really helped develop chemotherapy or the “magic bullet” theory, i.e., a single, very focused therapy would go straight to its target and not hurt the other tissue. However, scientists noted that this could go wrong and; therefore started what was known as “horror autotoxicus”, the idea that the body was attacking itself. In Rheumatology, the identification of autoantibodies, specifically rheumatoid factor (RF) and anti-nuclear antibodies (ANA) came about in the 1940s and really brought B cells into the forefront.  In 1952, Bruton researched  X-linked agammaglobulinemia, and the 1960s researchers began to the identify B cells. In the 1960s and 1970s, there was very important work done in autoimmunity, specifically, clonal deletion, clonal anergy and idiotypic network.  In 1975, monoclonal antibodies were developed which really paved the way for modern immunology. In 1997, rituximab was approved for NHL. In 2006, rituximab received approval for RA and in 2011 it was approved for WG/MPA.

B cells are the source of all immunoglobulins and can be activated by antigen in conjunction with co-stimulatory signals provided by antigen-presenting cells (APCs) and T lymphocytes. If successfully stimulated, activated B cells differentiate into antibody-secreting plasma cells. Most plasma cells generated during the initial phase of clonal expansion are short-lived and tend to produce IgM antibody.

In the second phase of clonal expansion, high-affinity (germinal center) B cells give rise to long-lived plasma cells and extremely long-lived memory B cells. When memory B cells re-encounter antigen, they rapidly differentiate into plasma cells and proliferate into more memory B cells. The plasma cells themselves are “terminally differentiated” and are no longer able to divide in response to antigen.

Ahmed R, Lanier JG, Pamer E. Immunological Memory and Infection. In: Kaufman SH, Sher A, Ahmed R, eds. Immunology of Infectious Diseases. ASM Press; 2002:175–189.

What do B Cells do in Autoimmune Disease?
  1. Production of autoantibodies
  2. Co-stimulation/antigen presentation
  3. Immunomodulation/cytokine secretion
  4. Lymphoid organogenesis

In rheumatoid arthritis, the efficacy and safety of rituximab has been demonstrated in several studies. With the use of rituximab also comes B cell depletion; however, only about 60% of patients respond; therefore, there is no correlation with clinical response. So what is the mechanism of depleting B cells? Is it bone marrow B cells? Is it synovial B cells? Scientists are still not sure what the specific target is.  We’re not always sure why they work. A related issue in rheumatoid arthritis is a biomarker and the idea of personalized medicine. The patients who were positive for RF or ANA, tended to do better with rituximab.  

Many open studies showed that perhaps B cell therapy would work in SLE.

Why did the EXPLORER study fail?

There was no statistical significance between rituximab and placebo and there were no differences by AUC of total activity, landmark analyses, or flares in “responders”.

The study demonstrated that rituximab significantly depleted CD19+ B cells and there were significant reductions in adsDNA, ACL Abs; memory CD8+ T cells. In summary, high dose steroids with prolonged taper may have blunted the effects of rituximab, and longer term follow-up may have shown beneficial effect but open-label extension was cancelled due to PML concerns. Healthcare providers should also be aware that BILAG is a difficult instrument to use and/or adjudicate.

There is another line of thought that is dedicated to the differential effects of rituximab on serum autoantibody levels, i.e., some diseases are rituximab-sensitive; some are partially rituximab-sensitive and some are rituximab-resistant.

We are now thinking of our targets based on the types of B cells that we may be eliminating or modulating with different types of therapies.

Targeting B Cells
  • Anti-CD20:
    • Rituximab
    • Ofatumumab (HuMax CD20):
    • Ocrelizumab
    • Trubion synthetic anti CD20
    • B-cell growth factors
      • BR3-Fc
      • Atacicept [TACI-Ig
      • Belimumab (anti-sBLyS)
      • Anti-CD22
        • Epratuzumab
        • Anti-CD40L (CD154)
          • Studies halted
BLyS/BAFF: Ensuring B Cell Survival

BLyS/BAGG is potentially expressed by multiple immune cells, specifically neutrophils, monocytes, B cells, activated T cells, plasma cell, and dendritic cells. It exists in membrane-bound and soluble forms. Three molecules bind together to form the trimeric soluble protein; soluble BLyS is considered to be the active form. BLyS is important in ensuring that new B cells mature, survive, and differentiate themselves. BlyS (BAFF) levels are elevated in patients with SLE.


Belimumab received FDA approval in May of 2011. The only prior FDA approved drugs for SLE were aspirin, prednisone, and HCQ. Belimumab is considered to be relatively safe, but its efficacy is modest (cutaneous outcomes; only significant for rash, not alopecia, oral ulcers: improved BILAG rash seen in placebo – 30% / 1 mg – 42% / 10mg – 44%). There is a question as to its utility as a steroid-sparing agent in milder lupus. The long-term efficacy, safety and cost of belimumab are yet to be determined.

Epratuzumab, the anti-CD22 mAb, is currently under study in SLE.
Anti-neutrophil cytoplasmic antibody (ANCA) Associated Vasculitis (AAV)

What about using B cell therapy in the ANCA-associated vasculitides? In the RAVE study (RTX vs CTX), rituximab demonstrated increased efficacy (63.6% v 51.1%).  Looking at long-term efficacy, a single course of rituximab is as effective as 18 months of standard therapy with cyclophosphamide and azathioprine.

Clinicians should also note that rituximab has also had a dramatic effect in patients with MS.

Safety Issues with B Cell Targeted Therapies

There are a number of safety issues with the use of biologic DMARDs in RA, including serious infections, opportunistic infections such as tuberculosis (TB), malignancies, demyelination, hematologic abnormalities, administration reactions, congestive heart failure, and autoantibodies and lupus.

Target Related

•Impaired humoral immunity / B cell costimulatory function

•Infections / serious infections

•Impaired vaccine responses

Agent Related

•Infusion / administration reactions:

•RTX: mostly on 1st infusion; mild (common) à severe (rare)

•RTX: lesser frequency / severity, RA vs NHL

•Immunogenicity: antibodies to treating agent

•RTX: HACA ~ 1% NHL studies; ~ 4%-12% RA studies

•? Clinical relevance ?


There is a lot of promise with targeting B cells. There are lots of potential mechanisms that may have varying efficacy and different safety concerns. There is a lot of excitement in the future for B cell directed autoimmune diseases. 

Pediatric Pearls Perfectly Repolished: Part 4 The Vitamin D Dilemma

Sheila Fallon Friedlander, MD

Dr Friedlander reviews the many questions that face clinicians regarding vitamin
D in their pediatric patients.  Patients still come in and ask and about what do regarding Vitamin D and sun protection;  as dermatologists it is important to provide them with accurate and useful information.

Historical Perspective

Why do we or should we care about Vitamin D? In the 1700s, it was noted that some children had “bowed” legs. Some of them also developed  tetany and laryngeospasm. This was more frequent during the industrial revolution  likely due to less exposure to direct sunlight. In 1921, sunlight was found to be a treatment for Vitamin D deficiency , in1922 cod liver oil was found to be helpful and in 1925 scientists identified Vitamin D1 and Vitamin D2. The concept that has evolved over the last few years is that of Vitamin D as the “super hormone.”  It is well established that Vitamin D is important for bone mineral density and bone strength and appropriate levels  decrease risk for fracture.  Over the last decade, several studies have demonstrated that Vitamin D may also protect us from certain types of cancer, multiple sclerosis and cardiovascular mortality; however, there is still much controversy around these studies.

How can Vitamin D do so much?

Vitamin D binds to cell surface receptors and nuclear receptors (VDR). The presence of polymorphisms in the receptor may be a reason why not all studies show the same results with the same Vitamin D levels. Vitamin D has an impact on gene expression and regulates growth and differentiation.

Vitamin D Synthesis

Vitamin D synthesis is a complicated process. The overall concept is that  precursors are present on the skin surface, and when the precursors are exposed to sunlight, we get one form of Vitamin D3, cholecalciferol That is then metabolized in the liver to another  form that can be measured. Finally, in the kidney, the final , active form is synthesized. This  active form, 1,25-Vitamin D3, does not have a long half-life, and therefore levels of this form are not used in clinical practice.

Vitamin D Deficiency—How much?

A recent study found that 70% of children in the United States have low levels of Vitamin D.  What is really a low level? This can be confusing and puzzling. as “normal” values vary depending on the expert discussing the isse and  healthcare providers have no perfectly clear standards . There were also some studies that rickets may also be increasing. In a study conducted in Glasgow, the researchers looked at all children with suspected Vitamin D deficiency from 2002-2008. There were a total of 160 cases, the median age was 24 months, the majority of the patients were dark skinned and 40% of the patients presented with bowed legs. (There was one seizure). There were twice as many cases of Rickets in 2008 as in the previous six years. The question is, are people looking harder now because they are more aware?

Why are dermatologists concerned about this?

As dermatologists, we tell our patients to protect themselves from the sun; therefore,  we are interfering with “the natural order” of getting sunlight. Are we putting our patients at risk with this advice? Is there really a problem?

The problem is that the ultraviolet action spectrum for Vitamin D photosynthesis is identical to that for DNA damage and skin cancer, so we cannot  separate out this action spectrum.

Known Facts

Ultraviolet radiation from the sun is a carcinogen. It is responsible for the  majority of 1.3 million cases of skin cancer in the United States every year. In animal models, ultraviolet radiation is directly related to squamous cell carcinoma, basal cell carcinoma and metastatic melanoma. The use of sunscreen decreases one’s risk of malignant melanoma. Ultraviolet radiation compromises the skin’s function and can negatively affect one’s appearance.

Sunscreen, Vitamin D & Skin Cancer

In a 2011 review by Burnett and Wang, they found that sunscreen use has little or no impact on clinically relevant Vitamin D levels. Eide et al, in 2011, showed us that an increased baseline serum 24-OH Vitamin D level was significantly associated with an increased non-melanoma skin cancer risk. Basically, the more Vitamin D people had, the more skin cancer they had.

Natural Sources of Vitamin D Other Than the Sun

It can be hard to get enough Vitamin D from food.

  • Milk (but  4 glasses needed to get 400 IUs)
    Not such a good idea for the lactose-intolerant
  • Salmon, mackerel – but you need wild for the highest amount (600-1000 IU  &   $$$$)
  • Shittake mushrooms
  • Cod liver oil (grandma was right!)
  • Eggs
  • Could make it if you eat mushrooms & salmon a lot

Some feel that a little sun may be helpful to get the extra Vitamin D, but how much?

We know that white skin is more efficient than dark skin at “procuring” Vitamin D conversion from the sun. White skin is also more vulnerable to the bad, cancer-associated effects of the sun. How much one needs really depends from patient to patient.

So where do experts  stand on this issue? In New Zealand, they feel that sun exposure depends on the time of year and UV index along with one’s skin type. In the summer months, they believe that people receive sufficient Vitamin D through incidental sun exposure outside peak UV times (11am-4pm). For skin types 1 or 2, the recommendation is 5 minutes per day to the face, hands and forearms. For skin types 5-6, the recommendation is up to 20 minutes per day. (www.dermnetnz.org) However, according to the AAD and the AAP, this is a no-go. They feel it is inappropriate to recommend intentional exposure to natural or artificial UV light in order to obtain Vitamin D.  These two organizations believe the risks clearly outweigh the benefits and Vitamin D should come from diets and supplements.

So, to the rescue came  supplemental Vitamin D3; however, it is still not clear  how much to give, but  researchers began to demonstrate the positive effects of Vitamin D3 and its potential to reduce many health risks; therefore, people began to supplement and supplement and supplement….In 2001, $40 million was spent on Vitamin D supplements, in 2009, $425 million was spent and the federal government took notice.

The government got involved and asked the Institute of Medicine (IOM) to provide some answers regarding Vitamin D:

  1. What health outcomes are impacted by Vitamin D levels?
  2. How much Vitamin D is needed for a beneficial effect?
  3. How much is too much?

The IOM determined that, with no sun exposure, 600 units of supplement is a good idea for just about everyone. Babies need a little less and older patients (70+) will do well with 800 units.  There many experts who felt that these levels were inappropriately low. Why would the IOM be so rigid about how much Vitamin D people need?…because the  risk-benefit data are not clear. The colorectal data is the most supportive; that is Vitamin D is protective. Prostate, pancreatic, and cardiovascular data is conflicting, i.e., there is data that shows an increased risk with higher doses. There is an increased risk of renal stones with modest (400mg) supplements. Some of these problems, as Dr Friedlander mentioned before, could be due to Vitamin D receptor polymorphisms.  There may be a U-shaped curve of response where a little is bad, a moderate amount is good, and too much is also bad.

The IOM and Their Conservative Recommendations

We should not base recommendations on imprecise, suboptimal data. Risks are also possible with increased dose.

It is important to remember that there is data that shows an increased risk of prostate and other cancers, increased cardiovascular mortality and stones with increased doses of Vitamin D. A little Vitamin D is bad, moderate amounts is good, and too much can be bad. For now, patients should stick with 600 IU/day, unless they are considered to be in a high-risk population. This includes breast fed infants, older adults, individuals who have limited sun exposure, people with dark skin, and those with fat malabsorption. Healthcare providers should consider blood levels and higher supplemental intake for  elderly adults and those with dorders putting them at risk for Vitamin D malabsorption..

Summary FAQs
  • Does everyone need to be supplemented?Not a bad idea
    Age IU
    <1 400
    1-70 600
    70+ 800
  • Should everyone get Vitamin D levels?No, it can be expensive.
    Yes, for high risk populations.
  • What kind of supplement is best?
    • Food
    • Vitamin D3


  • Is more Vitamin D better?Perhaps not
  • Does Vitamin D support bone Health?Absolutely
  • Does Vitamin D protect us from MS, cardiovascular disease and cancer?Evidence is imprecise, inconclusive, inconsistent and insufficient at this time
  • Should I get Vitamin D from the sun?Not needed
Vitamin D “Pseudo-controversy”

Sunlight (UVR) is a known carcinogen. You can’t make Vitamin D in your skin without inducing DNA damage. Vitamin D is certainly good for you and you can get a sufficient amount with incidental sun exposure and a reasonable diet +/- supplements.

What’s a clinician to do?
  • Adhere to IOM guidelines – for now
    • <1yr = 400 IU
    • 1-70 = 600 IU
    • 70+  = 800 IU,
    • Identify high risk groups, test prn,
      • Breast fed, dark skin, elderly, malabsorbers
      • Counsel your patients that supplements are more dependable & safer than sun exposure





Pediatric Pearls Perfectly Repolished: Part 3 Worry or Not Worry: Which Vascular Birthmarks Need Further Evaluation?

Ilona J. Frieden, MD


Sturge-Weber Update

Sturge-Weber syndrome (SWS) is the triad of a port wine stain involving a V1 distribution as well as brain vascular malformations and often times glaucoma along with other ocular sequalae.  A recent report, published in December of 2011, from the Brain Vascular Malformation Consortium and the Sturge-Weber Syndrome National Workgroup. The experts discussed the disease in a broader sense to really examine what is going on now with the disease, what can physicians do currently and what does future look like as far as new developments in science.

Neurologic  Status

Usually with PWS, the patient has roughly a 30% chance of having unilateral, ipsilateral brain involvement to the PWS; however, in some cases with bilateral PWS there can be bilateral brain involvement that can correlate to a poorer prognosis. Epilepsy was found in 75-80% of patients with SWS and the vast majority will have an onset by age one (75%). It important to know that if a child over the age of two presents with a PWS and have been asymptomatic neurologically they are unlikely to have SWS.  When looking at outcomes, cognition was variable but it was worse in patients with seizures. In older patients, migraines or migraine-like headaches were a major issue. Endocrine disorders, especially growth hormone  deficiency and central hypothyroidism, have also been seen in some  patients.

Imaging Studies: Which to Do and What They Tell Us

There really isn’t a right answer as to whether or not one should be doing routine imaging in all infants with PWS in a V1 distribution to assess for the possibility of Strurge-Weber. The standard imaging modality used MRI with contrast; however, that is not always diagnostic in young infants because it is not adequately sensitive. The newly developed Susceptibility Weighted Imaging (SWI) MRI may make earlier detection possible and is more sensitive for venous disease which also may be present as a part of SWS.   Currently, Dr Frieden typically does not routinely do imaging as this will not necessarily change management in otherwise asymptomatic children.  However she  does routinely send these at-risk children to an ophthalmologist.

Another important part of imaging studies, however, is in helping to  better understand the disease. Imaging has shown us that brain disease is progressive, not static in SWS and that though initially increased blood vessels and hyperperfusion are present, over time,  hypoperfusion of parenchyma develops and this  correlates with functional impact. Functional PET imaging is also playing an increasing role in prognosis and pre-surgery planning for patients with intractable seizures.

Future Diagnostic Directions

Quantitative EEG (qEEG) in a non-invasive test that uses math signal processing for interpretation, rather than looking at just the morphology of the spikes and waves. qEEG was able to distinguish young infants with and without SWS correctly with high reliability (but small numbers). Transcranial Doppler is a non-invasive flow measure used in Sickle-Cell disease and there are ongoing studies looking at this modality for studying SWS.

Infantile Hemangiomas

Infantile hemangiomas cause multiple potential risks. This infant has a risk of eye disease as well as PHACE syndrome.

How do we begin to approach infants like this early on?

PHACE Syndrome
  • P: Posterior fossa and other brain anomalies
  • H: Large facial hemangiomas
  • A: Arterial anomalies especially CNS anterior circulation
  • C: Cardiac anomalies and aortic coarctation
  • E: Eye defects especially retinal vascular anomalies

PHACE Syndrome is the most common neurocutaneous vascular syndrome and is more common than SWS.  This is present in 30% of infants with large facial hemangiomas (> 5 cm in diameter).

Segments 1 and 3 have a much higher risk (50% or higher) compared to segment 2.

Elements of a PHACE Work-up
  • At risk if facial infantile hemangioma ≥ 5 cm
  • MRI and MRA with contrast
  • Eye exam (even if no perioccular vascular lesions)
  • Cardiac echo (looking for coarctation of the aorta in particular)
  • Consider other tests
    • ENT evaluation if “beard area”
    • Hearing tests (sensory-neural hearing loss independent of ear canal occlusion from a hemangioma)
    • Thyroid functions (occasionally central hypothyroidism is an issue)

The MRI and the MRA need to be individualized by patients due to the need to perform general anesthesia to due these procedures.

 Beard Area Segmental IH

Dermatologists should realize that hemangiomas distributed in the so-called “beard-area  pose a high risk of both airway disease and of PHACE.

Multifocal Hemangiomas

A prospective study by Horii et al, published in 2011, looked at the risk of liver hemangiomas in patients with multiple infantile skin hemangiomas. Abdominal ultrasound was performed on infants 6 months of age or less with 5 or more skin IH. They were compared with 50 infants who had 1-4 IH (control group). 24 (16%) of the 151 infants with 5 or more skin hemangiomas had hepatic hemangiomas (HH) versus 0/50 with less than 5 cutaneous (p = 0.003).

HH are similar to skin IH, in that, not all HH need treatment. More cutaneous IH are associated with a greater overall risk of HH but they are not necessarily more severe. In the prospective study mentioned above, only two of the 24 patients who had HH needed treatment specifically for the HH because they caused symptoms.

Risk of Life-Threatening “Diffuse” Disease

This is the feared complication of liver hemangiomas; whereby the liver is replaced by hemangiomas. In a recent study, the researchers found that the time to presentation for these patients is between a few weeks and 4 months. Symptoms include abdominal distention and poor feeding. If children have this, it is imperative to consider severe hypothyroidism, as it is commonly associated. The hemangioma itself causes a consumptive hypothyroidism by de-iodinating T3.

Do I need to worry about GI bleeding?

Dr Frieden states that most of us were taught that we needed to worry about GI bleeding when we saw patients with multiple hemangiomas. That actually turned out to be false. Large facial such as those seen in PHACE Syndrome, not multifocal IH, is a major risk factor for GI hemangiomas; usually in the small intestine.  In contrast, when you see multiple vascular lesions together with visceral involvement in sites such as the  brain, gastrointestinal tract, kidney, spleen, or adrenal glands this is more likely to be due to other multifocal vascular tumors such as multifocal lymphangioendotheliomatosis, rather than infantile hemangiomas.

Lumbosacral Hemangiomas

Regarding lumbosacral hemangiomas, dermatologists should worry about tethered cord and other anomalies.  In a 2010 prospective study by Drolet et al, the researchers studied 41 infants with IH greater than 2.5 cm midline overlying lumbar or sacral spine. The patients were imaged with ultrasound, MRI or both. The spinal abnormalities that were noted included lipoma or hemangioma and structural malformations of cord/tethered cord. Nearly 50% (21/41) had tethered cord, intraspinal hemangiomas, or both. High-resolution ultrasound was not optimal for evaluation (sensitivity 50%; specificity 78%).

Nevus Simplex (Salmon Patch)

The incidence of the nevus simplex also known as the salmon patch, is quite high (greater than 15%; range 19-82%). How do we know that this isn’t a Port Wine Stain? Clues to this diagnosis include its medial location and very blotchy, less well-demarcated borders.   We know that the classic locations include the glabella, the eyelids as well as the nape. Dr Frieden and colleagues have reported on some cases of extensive nevus simplex that included additional sites such as the scalp (67%), the nose (67%), the lip (60%), lumbosacral skin (56%) and the upper and mid back (15%). In this case series, most of the children were referred to Dr Frieden’s group because of the vascular anomalies. There were no associated abnormalities and imaging was not needed.

“Nevus Simplex Complex”

Infants with widespread nevus simplex were termed “Nevus simplex complex”. The patients had no other conditions. In a literature search, however, prominent NS was found to be associated with some rare syndromes such as:

  • Beckwith-Wiedemann
  • Macrocephaly-Capillary Malformation
  • Ondotodysplasia
  • Roberts-SC phocomelia
  • Nova syndrome

We also know that there is also an increased incidence of NS in infants with IH. Of note, patients with NS respond very well to pulsed dye laser treatment.

In 2011, Sillard et al published on a condition they termed  “Medial Fronto-Facial Capillary Malformation.” This was a retrospective study of 84 children. The distribution was the same as that of nevus simplex complex with “extended forms” in 26%. Neurologic anomalies were found in 9.5% of the patients. The researchers argue that this “looks like salmon patch” but it is not the same; it is darker, wider, slower, and there is less complete resolution.




Pediatric Pearls Perfectly Repolished: Part 2 Rapamycin Sheila Fallon Friedlander, MD

In this presentation, Dr Friedlander  discusses the many clinical applications of rapamycin, a target of the P13K pathway which was previously discussed by Dr Frieden.

Is Rapamycin the new wonder drug for kids?

Rapamycin (sirolimus) is an immunosuppressant used to prevent rejection. It is a macrolide and derives from a  Streptomyces species. Rapamycin was first discovered on Easter Island (Rapa Nui) and was originally used an antifungal.. It  blocks the mammalian target of rapamycin (mTOR) pathway by affecting  cyclin-dependent pathways .  These pathways are essentially messengers which can mediate cell  proliferation, metabolism and angiogenesis.

If you think of mTOR as a conductor that is mediating the effect of various growth factors, then  if we have a substance  which can inhibit mTOR, we can impair cell proliferation, cell metabolism and angiogenesis.

Why do dermatologists care about Rapamycin?

There are several diseases with cutaneous manifestions in which  proliferation is a major component of the pathology, for which we have no safe effective treatment. There is evidence that Rapamycin may be effective in treating at least a few of these disorders; in particular  tuberous sclerosis, port wine stains have been investigated,  Rapamycin has also been utilized in an animal model of infantile hemangiomas.

It has been  established that Rapamycin significantly improves facial angiofibroma lesions in patients with TS.  What about port wine stains (PWS)? We know that PWS can recur after PDL treatment. It is hypothesized that the cell trauma of treatment stimulates new blood vessel growth.  Dr Stuart Nelson and others have conducted studies in animal models which show that rapamycin can inhibit regrowth of vessels following laser therapy.


Rapamycin is currently under investigation by Nelson and his colleagues to determine if PWS treatment outcomes can be improved with the use of rapamycin in addition to pulsed dye laser.

One of the challenges with Rapamycin, as found by De Klotz et al, is that of compounding the agent into the right formulation. Scientists are working on optimizing the formulation. Rapamycin is also rather expensive.

Side Effects

Because Rapamycin is an immunosuppressant we have to worry about oral ulcers, diarrhea, and infections, to name just a few concerns. Topical Rapamycin appears to have less side effects.

Rapamycin and Infantile Hemangiomas

In an animal infantile hemangioma model, rapamycin was able to suppress the growth of the tumor via the inhibition of stem cell renewal capability, vasculogenesis, and differentiation.  What’s the difference between angiogenesis and vasculogenesis?  Many healthcare providers are confused regarding angiogenesis and vasculogenesis.  Angiogenesis occurs when new  vessels sprout  and develop  from an existing vessel. Vasculogenesis is de novo new formation of a  vessel presumably from stem cells. The effect of Rapamycin is distinct from that of corticosteroids, i.e., the pathways are  very different.

The Promise of Rapamycin

Rapamycin is a topical  as well as systemic formulation that can inhibit angiogenesis, proliferation and perhaps vasculogenesis. Rapamycin also inhibits stem cell renewal. Given these characteristics, , it could well be an excellent therapy in topical formulation for both angiofibromas and PWS., and perhaps infantile hemangiomas.  However, we  do need to better investigate its possible  side effects before  utilizing on a wide scale basis.



Pediatric Pearls Perfectly Repolished: Part 1 Molecular Pathways: Towards a Better Understanding of Genetic Disorders Ilona J. Frieden, MD

In this presentation, Dr Frieden discusses molecular pathways and how the science can be applied into clinical practice in order to optimize the outcomes for patients with dermatologic diseases.

 The concept of Molecular Pathways

Dr Frieden’s concept of molecular pathways is described here. Signaling pathways are essential in regulation and growth development. These pathways are the key to understanding of the phenotypic overlap of many genetic disorders because even diseases with distinct genetic causes can show overlap if they involve a molecular pathway because the defect can be present either upstream or downstream of another condition and thus show similar features.  Understanding these pathways can  also help to bring us closer to more rational therapies because if we find things that inhibit overactivity of an element of a pathway, it may work not just for one disease but for several.

 RAS/MAP Kinase Pathway

The RAS/MAP kinase pathway is essential to our central understanding of melanoma genetics, for example melanomas with mutations in NRAS and BRAF. This pathway also plays a major role in NF1 and other genetic syndromes.


Collectively germ-line genetic diseases in this pathway can be referred to as “Rasopathies”.  They include Noonan syndrome, cardiofaciocutaneous syndrome, NF1, and Legius syndrome.  All share in common features of developmental delay and most also have café-au-lait macules as a common feature.


Geneticists call this group (CFC, Noonan, NF-1, and Costello) of overlapping disorders RASopathies.

Another Important Pathway: PI3K

PI3K stands for phophatidylinositol-3-kinase, and the pathway in which PI3K is involved  is sometimes called the PI3K/AKT/mTOR pathway. This pathway is critical to cell growth and survival. It is intimately involved in normal vascular development and angiogenesis. The mammalian target of Rapamycin (mTOR) integrates signals from the pathway to coordinate cell growth and proliferation both in the fetus and continues to work later in post-natal life as well.


PTEN is the most important negative regulator of the cell-survival signaling pathway initiated by P13K. There is also crosstalk between P13K pathways and other tumorigenic signaling pathways, such as those that involve Ras, p53, TOR (target of rapamycin) or DJ1, can contribute to this deregulation.

Genetics of Proteus Syndrome

Based on a paper published by Lindhurst et al in 2011, we now know that the cause of Proteus Syndrome is due to mutations in the oncogene AKT1 that is found right in the center of the P13K pathway. The researchers in this study conducted exome sequencing of DNA from biopsy samples obtained from patients with the Proteus syndrome—158 samples from 29 patients. 26 out of the 29 had a somatic activating mutation in the oncogene AKT1. Tissues and cell lines harbored admixtures of mutant alleles that ranged from 1% to approximately 50%. Two of the 38 peripheral-blood DNA samples were positive for the mutation compared with affected tissue (75 of 97, P<0.001) and unaffected samples that were positive (13 of 41, P = 0.004). This was a very important breakthrough as it determined that AKT1 was the cause of Proteus syndrome.

PI3K Syndromes: Overgrowth is a Common Motif

  • Cowden and Bannayan syndrome (PTEN)
  • Proteus (ALK)
  • Tuberous Sclerosis
  • Capillary Malformation-AVM and Parkes Weber
  • Familial venous malformations

Diseases Probably in the Pathway (but not proven)

  • Macrocephaly-Capillary Malformation
  • CLOVE syndrome
  • Diffuse capillary malformation with overgrowth
  • Probably others…

Clinical Pearls– Pathways help to explain the overlapping phenotypes of distinct genetic diseases. They help us to think about candidate genes for unknown disorders because they can lead us to look at certain candidate genes to see if they may be the cause of other phenotypically similar conditions. Pathways may also provide important molecular targets for treating previously untreatable diseases.