title: Pemphigus vegetans associated with intranasal cocaine abuse.
abstract: BACKGROUND
  Pemphigus vegetans is a rare variant of pemphigus vulgaris, comprising 1 to 2% of all pemphigus cases. Exposures to oral agents such as captopril and penicillamine and, less commonly, physical or chemical factors have been implicated in the development of pemphigus.
  
  
  METHODS
  We report a 42-year-old white male with a 12-month history of hypertrophic, vegetative plaques affecting primarily his external nares and upper lips. The patient had a history of alcoholism and intermittent drug abuse, primarily intranasal cocaine, since his youth. He had been using cocaine heavily three to four times/week for 1 month prior to and 1 month following the onset of the eruption but has since ceased use. His clinical features and histopathologic findings were consistent with a diagnosis of pemphigus vegetans. Treatment with high-dose prednisone (80 mg/d) and mycophenolate mofetil (1.5 g/d) resulted in resolution of the lesions after 18 months.
  
  
  CONCLUSIONS
  To our knowledge, this is the second report proposing an association between intranasal cocaine use and the pemphigus family of disorders. Although the relationship between illicit drug use and the development of pemphigus is unclear, we postulate that intranasal cocaine abuse is operative in our patient's disease. Herein we discuss drug and other external precipitants of pemphigus and review previous case reports of pemphigus associated with illicit drugs.
authors.affiliation: Department of Medicine, University of Calgary, Calgary, AB, Canada. jtvngo@ucalgary.ca
authors.forename: Jennifer T
authors.initials: JT
authors.lastname: Ngo
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Trotter
authors.forename: Lynne H
authors.initials: LH
authors.lastname: Robertson
mesh_terms: D000281:Administration, Intranasal; D000328:Adult; D001706:Biopsy; D003042:Cocaine / Q000008:administration & dosage / Q000009:adverse effects*; D019970:Cocaine-Related Disorders / Q000150:complications*; D003937:Diagnosis, Differential; D018765:Dopamine Uptake Inhibitors / Q000008:administration & dosage / Q000009:adverse effects; D005500:Follow-Up Studies; D006801:Humans; D008046:Lip; D008297:Male; D010392:Pemphigus / Q000139:chemically induced* / Q000175:diagnosis; D012867:Skin / Q000473:pathology
chemical_list: D018765:Dopamine Uptake Inhibitors; D003042:Cocaine