title: Epidemiology and Co-Reactivity of Novel Surfactant Allergens: A Double-Blind Randomized Controlled Study.
abstract: BACKGROUND
  Surfactants are cleansing agents used in products such as shampoos and soaps.
  
  
  OBJECTIVE
  The aims of this study were to identify positivity rates to 3 novel amide-containing surfactants (sodium lauroyl sarcosinate, isostearamidopropyl morpholine lactate, and disodium lauroamphodiacetate) and evaluate co-reactivity with other surfactants in patients with known surfactant sensitivity.
  
  
  METHODS
  Previously patch-tested, surfactant-positive patients were identified via chart review and invited to participate. Participants were patch tested to screening surfactants (cocamidopropyl betaine, amidoamine, dimethylaminopropylamine, cocamide diethanolamine [DEA], oleamidopropyl dimethylamine, and decyl glucoside), as well as 3 novel surfactants: sodium lauroyl sarcosinate 0.5% and 1.0% aq, isostearamidopropyl morpholine lactate 0.5% and 1.0% aq, disodium lauroamphodiacetate 1.0 and 2.0% aq, and a hypoallergenic liquid cleanser (tested semiopen). Participants and clinicians were blinded. The order of tested allergens was randomized.
  
  
  RESULTS
  Forty-seven participants completed the study. Excluding doubtful reactions, positive reactions were most common to oleamidopropyl dimethylamine (34%) and dimethylaminopropylamine (34%), followed by isostearamidopropyl morpholine lactate (23%). Reactivity was not associated with history of childhood eczema. Co-reactivity was high among oleamidopropyl dimethylamine, dimethylaminopropylamine, cocamidopropyl betaine, amidoamine, and isostearamidopropyl morpholine lactate. None of the participants who reacted to cocamide DEA reacted to an additional surfactant.
  
  
  CONCLUSIONS
  Isostearamidopropyl morpholine lactate may be an important emerging allergen with sensitivity rates comparable with those of oleamidopropyl dimethylamine and dimethylaminopropylamine. Co-reactivity among surfactants was frequent except for cocamide DEA.
authors: From the *University of Minnesota Medical School; †Parkside Occupational and Contact Dermatitis Clinic, Hennepin County Medical Center; ‡Department of Dermatology, Minneapolis Veterans Affairs Medical Center; and §Department of Dermatology, University of Minnesota Medical School, Minneapolis, MN.
authors: Katherine R
authors: KR
authors: Grey
authors: Jamie L
authors: JL
authors: Hanson
authors: Solveig L
authors: SL
authors: Hagen
authors: Sara A
authors: SA
authors: Hylwa
authors: Erin M
authors: EM
authors: Warshaw
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000485:Allergens / Q000009:adverse effects*; D017449:Dermatitis, Allergic Contact / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010328:Patch Tests; D012521:Sarcosine / Q000009:adverse effects / Q000031:analogs & derivatives; D013501:Surface-Active Agents / Q000009:adverse effects*; D055815:Young Adult
chemical_list: D000485:Allergens; D013501:Surface-Active Agents; C025231:sarkosyl; D012521:Sarcosine