Post-trauma Mycobacterium avium chronic Rhinosinusitis Mimicking a Neoplasm.

An 83-year-old Japanese man visited our hospital complaining of pain on the left side of his nose that had persisted for one month. Head computed tomography (CT) showed mucosal thickening and bone erosion in his left maxilla (yellow arrow), with a medial wall defect (blue arrow) and an old nasal bone fracture (Picture 1). One-year clarithromycin treatment (200 mg/day) for chronic rhinosinusitis (CRS) was ineffective. Based on the suspicion of a neoplasm, open reduction surgery of the nasal bone with curettage of the maxilla was performed, revealing an epithelioid (E) and necrotizing (N) granulomatous lesion that was acid-fast stain-positive (Picture 2). Mycobacterium avium was recovered from the tissue; the minimum inhibitory clarithromycin concentration was 1.0 μg/mL. Chest CT and sputum culturing showed no evidence of pulmonary Mycobacterium infection. Anti-glycopeptidolipid IgA was detected (1.7 U/mL). The final diagnosis was Mycobacterium avium-associated CRS. Unlike similar patients (1,2), ours patient had never undergone endoscopic sinus surgery. We hypothesize that the etiology of Mycobacterium infection was facial trauma, which he had experienced 30 years previously. It is noteworthy that Mycobacterium avium-associated CRS mimicked a sinus tumor.

Picture 1.

Picture 2.

The authors state that they have no Conflict of Interest (COI).