The role of ANCA in the management of cocaine‐induced midline destructive lesions or ENT pseudo‐granulomatosis with polyangiitis: a London multicentre case series

Objective In this multicentric study involving three London hospitals, we compared ANCA‐positive and ANCA‐negative cocaine‐induced midline destructive lesions (CIMDL) patients to assess how presence of antineutrophil cytoplasmic antibodies (ANCA) may correlate with disease severity. Our secondary aims are to better classify etiology centered around ANCA positivity and, consequently, better disease management. Methods A retrospective review was performed to identify patients with CIMDL seen between January 2019 and December 2022. Population data including age, sex, presentation, endoscopic findings, duration of cocaine use and active use of cocaine, type of treatment, laboratory (including ANCA serology), radiological, and histological findings were collected. Results Forty CIMDL patients (25 male, median age of 42 years) were identified. The majority of them (72.5%) presented with either a septal perforation, a saddle nose deformity (22.5%), and/or a palatal fistula (20.0%). ANCA was positive in 71.1% of cases (66.7% p‐ANCA). No statistically significant differences in the general characteristics, type of treatment, laboratory results, radiological or histological findings were observed when comparing ANCA‐positive and ANCA‐negative CIMDL patients or when comparing p‐ANCA and c‐ANCA patients. Similarly, no statistically significant difference was obtained when comparing the pattern of distribution of lesions between the two groups. Conclusions A large percentage of CIMDL patients showed positive ANCA test (71.1%) and in the majority of the cases a p‐ANCA pattern specifically targeting PR3 (p‐ANCA, PR3 + MPO‐). However, ANCA positivity or presence of a specific ANCA pattern was not associated with more severe presentation or more aggressive disease. Given its similarities to granulomatosis with polyangiitis (GPA), we recommend the use of the term “cocaine‐induced ENT pseudo‐GPA” instead of CIMDL. Level of Evidence IV Laryngoscope, 134:2609–2616, 2024 Repeated cocaine use can lead to damage to the nose and contiguous structures. Nasal lesions can appear similar to those in other autoimmune diseases (i.e., some vasculitis) and patients can show a positive antineutrophil cytoplasmic antibodies (ANCA) test. Our multicentric study shows that p‐ANCA pattern is the commonest pattern among patients with cocaine‐induced midline destructive lesions (specifically p‐ANCA PR3 + MPO‐) although ANCA positivity or presence of a specific ANCA pattern is not associated with