Pearls from ACP July 2019
Psoriasis may be exacerbated by streptococcal infection, skin injury (sunburn or drug reaction) or HIV disease. Think of the 5 P’s for the diagnosis of lichen planus - pruritic, purple, polygonal, planar, papules. Porphyria cutanea tarda is associated with heavy alcohol consumption, hepatitis C, and iron overload (especially hepatitis C- 70% of PCT patients have hep C) Clinical features include facial hirsutism, milia, erosions, scars and tense bullae (frequently on hands). Pemphigus vulgaris often involves the mouth (50%). Diagnosed by immunofluorescent studies of perilesional skin. High fatality rate if not treated. Erythema nodosum: Think Inflammatory bowel disease, sarcoid, strep infection , or drugs (OCP most common) Erythema Multiforme: “Target lesions” : Think HSV, drugs (PCN, Sulfa and Phenytoin most common), or Mycoplasma. For patients with recurrent erythema multiforme, a trial of acyclovir therapy is appropriate Acanthosis nigricans is most often seen in association with obe...