Mycobacterium avium-intracellulare pulmonary infection complicated by cutaneous leukocytoclastic vasculitis in a woman with anorexia nervosa.

A 53-year-old Caucasian woman with a history of anorexia nervosa developed a bilateral lower extremity rash comprised of palpable red to violaceous, sub-centimeter papular lesions that increased in quantity rapidly. She also noted a 2-month history of non-productive cough. Imaging modalities revealed a thin-walled cavitary lesion in the right lung apex and scattered nodular opacities. Acid fast bacilli (AFB) were found in sputum and subsequently identified by culture as Mycobacterium avium-intracellulare (MAI). Punch biopsies of her skin lesions yielded a histological diagnosis of small-to-medium vessel vasculitis. Stains and cultures for organisms were negative. Her skin lesions resolved quickly after the initiation of antimicrobial therapy for MAI. Hypersensitivity vasculitis associated with an atypical mycobacterial infection is unusual. The postulated underlying mechanism is the deposit of immune complexes and not the bacillus itself. While cutaneous leukocytoclastic vasculitis (CLV) due to MAI is certainly a rare entity, it should be entertained in patients with vasculitic skin lesions and a concomitant pulmonary disease.