title: Necrotic facial papules in an adolescent: C2 deficiency with eventual development of lupus erythematosus.
abstract: A 14-year-old girl was admitted to the hospital because of persistent throat pain, fever, fatigue, 25 pound weight loss, and leukopenia. On physical examination she was thin, ill-appearing, and had necrotic papules on the face and palpable cervical lymph nodes. Presumptive differential diagnosis included occult malignancy and infection. Numerous investigative procedures failed to elucidate a source. Vasculitis was eventually appreciated after repeat skin biopsy. Numerous serologic studies were performed and were notable for a very low level of the second component of complement without direct evidence of lupus erythematosus (LE) or other autoimmune conditions. A diagnosis of C2 deficiency-associated vasculitis was made. She was treated with high-dose prednisone and cyclophosphamide with resolution of her symptoms. Two years later she returned with marked malar erythema. Antinuclear and Smith antibodies were then detected and a diagnosis of LE was made. She was treated with hydroxychloroquine and sun-avoidance measures with clearance of the malar rash.
authors.affiliation: Department of Dermatology, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Valerie B
authors.initials: VB
authors.lastname: Lyon
authors.forename: James J
authors.initials: JJ
authors.lastname: Nocton
authors.forename: Beth Ann
authors.initials: BA
authors.lastname: Drolet
authors.forename: Nancy B
authors.initials: NB
authors.lastname: Esterly
mesh_terms: D000293:Adolescent; D003175:Complement C2 / Q000172:deficiency*; D005148:Facial Dermatoses / Q000209:etiology* / Q000473:pathology* / Q000628:therapy; D005260:Female; D006801:Humans; D008178:Lupus Erythematosus, Cutaneous / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D009336:Necrosis; D014657:Vasculitis / Q000209:etiology* / Q000473:pathology / Q000628:therapy
chemical_list: D003175:Complement C2