CASE PRESENTATION: A 52 year old man presented to the emergency department with 2 months history of fatigue, anorexia, low grade fever, and nonproductive cough. He was diagnosed with B-cell lymphoblastic leukemia and was started on cytoreductive chemotherapy. The patient continued to have low grade fever and green sputum production despite being on cefepime and fluconazole for 15 days. CT of the chest showed stable bibasilar tree-in-bud opacities. Bronchoalveolar lavage (BAL) of the right lower lobe was then obtained, but no organisms were identified on bacterial and fungal stains and cultures. Galactomannan in BAL and serum were negative. However, bronchoscopy also revealed a large nonbleeding ulcer in the bronchus intermedius; endobronchial biopsies were obtained and histopathology revealed narrow 45 degrees branching hyphae. This was suggestive of aspergillus ulcerative tracheobronchitis. He was started on voriconazole and 2 days later he defervesced. 1 week later surveillance bronchoscopy was repeated and showed that the ulcer was stable in size with no necrosis or bleeding.