A69-13 Invasive Pulmonary Aspergillosis Secondary to Aspergillus Niger

Abstract Introduction Invasive pulmonary aspergillosis (IPA) is a fungal infection most commonly affecting immunocompromised patients. Aspergillus fumigatus, Aspergillus flavus, and Aspergillus terreus are the most common culprits. Less commonly, IPA can be caused by Aspergillus niger. While a definitive diagnosis requires lung biopsy, we present a case of Aspergillus niger IPA based on clinical and radiographic features. Case Report A 48-year-old male with alcohol use disorder and diabetes presented with diarrhea and a 5-month history of unintentional weight loss of approximately 30 pounds. He also reported subjective chills and fever. He was found to be in diabetic ketoacidosis with a hemoglobin A1c of 19.3%. Initial chest radiograph revealed right middle lobe collapse and ill-defined opacities in the right middle lung base. CT chest showed scattered nodules, a right cavitary lesion, areas of ground glass opacification with peripheral consolidation consistent with atoll sign, and a filling defect within an ill-defined pulmonary opacity of the left upper lobe. Bronchoscopy with bronchoalveolar lavage (BAL) of the bilateral upper lobes and endobronchial biopsies were performed. On inspection, the anterior segment of the right upper lobe was covered with thick mucopurulent material. After debridement, black, necrotic-appearing mucosa was visualized. BAL and tissue cultures grew Aspergillus niger, Candida albicans, Candida krusei, and Klebsiella pneumoniae. He was treated with a course of voriconazole and amoxicillin-clavulanate. Discussion Atoll sign, also known as reverse halo sign, describes a focal area of ground-glass opacification surrounded by a denser rim. It indicates an inflammatory response where necrotic cellular debris are surrounded by reactive consolidation. Differentials include organizing pneumonia, fungal pneumonia, pulmonary infarct, granulomatosis with polyangiitis, and malignancy. In this patient, fungal infection (ie. mucormycosis, aspergillosis) was most likely given his immunocompromised state in the setting of poorly controlled diabetes. The presence of atoll sign and a perfusion defect with surrounding consolidation clues us into angioinvasive fungal disease: distal to the angioinvasion, decreased perfusion leads to tissue necrosis and inflammatory changes. Scattered nodules with surrounding halo sign further supported a diagnosis of fungal infection. A definitive diagnosis of IPA requires lung biopsy with vascular invasion on histopathologic exam. However, this is often not feasible given the risk of bleeding with lung biopsy. Often, a clinical diagnosis of IPA is made through positive cultures, risk factors, and radiographic findings. Given the concern for invasive fungal infection visualized on bronchoscopy and imaging findings consistent with infarct, the patient was diagnosed with angioinvasive Aspergillus niger. This abstract is funded by: None