Cocaine-induced midline destruction lesions with positive ANCA test mimicking Wegener's granulomatosis.

Chronic use of cocaine by inhalation may induce midline destructive lesions (CIMDL), which can sometimes be difficult to distinguish from the ear, nose and throat lesions of Wegener's Granulomatosis (WG). We describe the case of a 43-year-old female patient admitted with a two-year history of nasal obstruction and rhinorrhea. She had been diagnosed with WG for five months, being on prednisone and cyclophosphamide. On her physical examination, perforation of her nasal septum and palate was observed. Laboratory tests showed elevated acute phase proteins and a positive p-ANCA test. ELISA assays anti-proteinase 3 and myeloperoxidase were negative. The paranasal sinus computed tomography (CT) showed destruction of the nasal septum and palate, in addition to bilateral maxillary sinusitis. Chest CT was normal. Nasal mucosal biopsy revealed an inflammatory infiltrate, with neither granuloma nor vasculitis. When questioned, she admitted being a cocaine user for five years. Medical therapy and cocaine use were withdrawn. She has been followed up for six months and no other lesion or other organ symptoms occurred. Differential diagnosis in patients with midline destructive lesions can be very challenging. Evaluation should include enquiry about intranasal use of cocaine. Although ANCA testing does not clearly differentiate the ANCA found in some patients with CIMDL from those found in WG patients, the localized involvement and the biopsy findings non-characteristic of small vessel granulomatous vasculitis should be recognized as features for cocaine-induced lesions.