title: Relevance of patch testing in patients with nummular dermatitis.
abstract: BACKGROUND
  A chronic dermatosis like nummular dermatitis may be complicated by contact dermatitis due to an impaired cutaneous barrier. This study is aimed at evaluating secondary contact dermatitis in patients with nummular dermatitis.
  
  
  METHODS
  Patch testing with the Indian Standard Series was performed in 50 of 78 patients with a clinical diagnosis of nummular eczema. Significant reactions were graded as per ICDRG criteria.
  
  
  RESULTS
  Significant reactions were noted in 23 of 50 tested patients. The most frequent sensitizers were colophony, nitrofurazone, neomycin sulfate and nickel sulfate (7.14% each). Reactions to antigens in topical medications, cosmetics and toiletries constituted 64.28% of all the reactions.
  
  
  CONCLUSIONS
  Patients with nummular dermatitis are at significant risk of developing secondary allergic contact dermatitis, which contributes to the severity and chronicity of their dermatitis. Patch testing has the potential to improve the quality of life in these patients. Hence, patients with chronic recalcitrant nummular dermatitis must be patch tested.
authors.affiliation: Department of Dermatology, Manipal Hospital, Bangalore, Karnataka, India. dermakrupa@yahoo.com
authors.forename: D S
authors.initials: DS
authors.lastname: Krupa Shankar
authors.forename: Shristi
authors.initials: S
authors.lastname: Shrestha
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D015897:Comorbidity; D017449:Dermatitis, Allergic Contact / Q000453:epidemiology*; D004485:Eczema / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010328:Patch Tests