Eric Simpson discussed atopic dermatitis (AD):11% of children in the U.S. have AD, up to 12% in 2007. There is an increased severity in the U.S. in inner city children.
There is a strong association between atopic dermatitis and ADHD, also an association with autism. There is an increased frequency of diagnosis of ADHD in children with atopic dermatitis, with "dose response" for AD severity. The theory is that ADHD is a non-specific comorbidity of chronic disease in kids. A similar relationship was also seen with autism and AD. Does early life inflammation affect neurodevelopment?
An epidermal barrier dysfunction and immune dysfunction (under genetic influences) interact to manifest as AD.
Recent meta analysis of AD prevention/allergen avoidance: HDM avoidance not recommended, limit maternal/infant diet not recommended.
Dietary restriction is of limited benefit in AD in good studies. A RCT of omalizumab was unsuccessful.
Etiology
A defective barrier function (e.g. filaggrin mutations) is extremely strong predictor of AD. Filaggrin (FLG) mutations are associated with AD, asthma, AR, IgE sensitization (Rosanne 2009). FLG deficiency may also be acquired, under cytokine influence.
Fillagrin mutations are also associated with keratosis pilaris and hyper-linear palms.
Epicutaneous sensitization is thought to be an important route of food allergy developemnt, it could explain the strong association between food allergy and AD. Environmental exposure to peanut (PN) protein in home is a strong predictor of PN allergy, possibly due to defective skin barrier (Lack 2011).
Treatment
There are 3 key education points at the first patient visit for atopic dermatitis: address steroid phobia; causation; and food allergy. The initial visit for AD must focus on education: steroid phobia, causation (not food usually!), and skin care. The use of topical treatments decreases within days, so rapid follow up is important for AD clearance.
The risks of undertreatment of AD outweigh risk of steroids; food allergy is associated but not causative, the lecturer doesn't recommend food SPTs.
Dr. Simpson spends a full 30 minute period on education, and gives a clearance protocol, then follows up in 1 week.
The initial therapy consists of: baths b.i.d, mid-potency topical steroid within 3 minutes of the bath. Follow up rapidly in the clinic in 1 week to ensure response. Clearance protocol: bath twice a day, immediately apply triamcinolone 0.1% ointment afterwards, also twice a day, add antibiotic if infected.
The consistent maintenance therapy decreases relapse/flare time significantly. The maintenance therapy consists of: frequent baths and moisturizers, and anti-inflammatory treatment 2-3 times per week (even to normal skin areas if prone to flares). Off-label use of anti-inflammatory cream (steroid) twice weekly on NORMAL-appearing skin may prevent flares. Normal appearing skin in patients with AD still show multiple abnormalities when biopsied. Abnormalities include: change in pH, xerotic appearance of stratum coreum and decreased anti-microbial peptides.
Electronic monitoring of patients where detection of opening of cap of steroid cream were done, and showed only 30% usage after 1 week.
Flare prevention: bathe as often as you want; moisturize - moisturize - moisturize!, twice weekly topical steroid to active areas.
Consider pimecrolimus ointment or tacrolimus ointment three times per week for those who fail twice weekly corticosteroids.
Systemic therapy
Rebound AD flares are common with PO steroids, avoid them whenever possible. Dr. Simpson never uses PO corticosteroids in atopic dermatitis due to severe rebound flares with discontinuation.
Consider cyclosporin 5 mg/kg (better than 2-3 mg/kg) in refractory AD for rapid improvement, limit to 12 months of therapy. Cyclosporine 5 mg/kg works in 2 weeks but can only be on for 1 year in total. Watch for renal function impairment and HTN as complications. Next, the lecturer uses phototherapy, followed by methotrexate, azathioprine and mycophenolate, possibly interferon gamma but it is expensive.
Consider methotrexate, azathioprine, mycophenolate, interferon-gamma, and phototherapy, if refractory AD.
Other areas of AD research
Eczema prevention strategies: altering maternal or infant diet and HDM avoidance are not recommended
Regular application of emollient creams in 1st 6 mos of life was protective against development of AD in a pilot study. In this pilot study, emolient therapy from birth suggested benefit towards preventing AD development - 43.4% developed eczema in the control group compared to 21% in the emolient group.
Antihistamines are of minimal benefit for itch and inflammation, some physicians use only sedating antihistamines to help sleep. Q from audience: Ever use antihistamines? A: Only at night if sleep disturbance is an issue.
Ceramides are not tremendously effective compared to less costly emollients and topical steroids.
Twitter summary made possible by @allergydoc4kidz @DrAnneEllis @IgECPD4
Three allergists did a great job posting updates from the 2012 meeting of the Canadian Society of Allergy and Clinical Immunology (#CSACI): @allergydoc4kidz @DrAnneEllis @IgECPD4. Compared to year 2011, this represents 300% growth in Twitter use by the Canadian allergists. The AAAAI has a larger audience and not surprisingly 30 allergists posted Twitter updates from the 2012 #AAAAI meeting. I used the website “All My Tweets” to review the updated from each allergist, for example: http://www.allmytweets.net/#@IgECPD4
For comparison, here are the tweets from the 2011 #CSACI meeting: http://allergynotes.blogspot.com/search/label/CSACI
Figures:
Comments from Twitter, LinkedIn and Facebook:
David Fischer, MD @IgECPD4: Ves, thanks for collating our tweets. Are you doing other topics we tweeted about as well?
Ves Dimov, M.D. @Allergy: Yes, I plan to post 4-5 summaries: asthma, IT, FA, SLIT - just like with any other tweeted meeting - #AAAAI #ACAAI #CSACI 2011
David Fischer, MD @IgECPD4: If you want to read all the #CSACI tweets I did (& more), here's a link bit.ly/T0jM7j Thanks @Allergy for pointing this out. Want all your tweets on 1 page? Try allmytweets.net via @Allergy Here's my link: allmytweets.net/#@IgECPD4
Thanks for doing this. It's very rewarding to see them all together & interesting to note the power of the combined messages.
For summaries of topics tweeted by me @DrAnneEllis & @allergydoc4kidz re: #CSACI check out @Allergy He'll be posting them in the next while.
Yesim Y Demirdag @DrYesimDem: Awesome! Thank you Ves for putting all messages together, and many thanks to friends who contributed.
Tanya Pilcz: Great info, thanks for posting!! I have an honest curiosity question I've always wondered about. If the docs think that food sensitization can occur through an impared skin barrier, wouldn't it follow that skin prick testing could cause allergy? I've always wondered about that, especially since they SPT peanuts prior to any symptoms of peanut allergy. http://on.fb.me/OJXWsu
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