Chronic necrotizing aspergillosis
Gentile J, and Chen A. Chronic necrotizing aspergillosis. Chest 2016; 150(4 Suppl):167A.
INTRODUCTION: Chronic Necrotizing Aspergillosis (CNA) is a term used to define an indolent, locally invasive form of pulmonary aspergillosis that often presents in the upper lobes among patients with either preexisting lung disease or immune suppression. It is usually characterized by chest pain, cough, sputum production, hemoptysis, and fatigue. Slow progression of disease is best characterized on CT scan. CASE PRESENTATION: A 58-year-old woman with ulcerative colitis (UC) on infliximab, initiated five months previous, and no history of lung disease presented with diarrhea, fatigue, and weight loss of a few weeks duration. Though she denied pulmonary complaints, save a chronic dry cough, CT of the abdomen revealed new cavitary lesions of the right lower lobe that were not present on previous CT. Her serum beta-d-glucan was >500 pg/mL. A bronchoaveolar lavage (BAL) galactomannan returned at 10.65 ng/mL. Serum antineutrophil cytoplasmic antibody titers, as well as histoplasma antigen, cultures for acid fast bacilli, viruses, and Legionella from her BAL returned negative. Fungal cultures grew Aspergillus niger. She was treated with voriconazole. CT at her three month follow up showed near-complete resolution of her cavitary lesions. DISCUSSION: Due to the nebulous nature of the disease, the diagnosis of CNA is often difficult. BAL, transbronchial, and percutaneous aspirates often fail to grow fungi. A diagnosis generally requires a combination of Aspergillus serology, radiographic evidence, and constitutional symptoms with exclusion of other common causes of cavitary lung lesions. BAL galactomannan is more specific for the diagnosis of pulmonary aspergillosis than a serum sample, especially if used at a higher cut off than the FDA standard. In a meta-analysis, a 1 ng/mL cutoff of galactomannan in fluid from a BAL yielded a sensitivity and specificity of 85% and 94% respectively, with a positive likelihood ratio of 14.29. CONCLUSIONS: Given the slowly progressive nature of CNA, diagnosis at an early stage can be difficult without a high degree of clinical suspicion. The initial nonspecific symptoms of weight loss and fatigue were initially thought secondary to her UC. It is fortunate that the CT abdomen detected the atypical presentation of lower lobe pulmonary cavities preventing treatment with high-dose steroids combined with continuing cycles of infliximab, which would have lead to disseminated aspergillosis and significant morbidity or death. It is essential to have a high clinical suspicion for opportunistic infections, such as CNA, in immunosuppressed patients as they are both at increased risk and more likely to manifest with an atypical presentation.