A Case of Miliary Pulmonary Cryptococcosis Showing Different Changes in Computed Tomography Images of the Left and Right Lungs

Abstract

Pulmonary cryptococcosis is a fungal infection with diverse images, particularly in immunocompromised individuals. We herein report a rare case of miliary pulmonary cryptococcosis exhibiting different changes in computed tomography (CT) images of the left and right lungs. The case was a 70-year-old patient with chronic lymphocytic leukemia (CLL) treated with ibrutinib, a Bruton tyrosine kinase inhibitor that suppresses humoral immunity. She was diagnosed with CLL in March 2019, and ibrutinib administration was initiated. After 4 months, she visited our hospital due to high fever and dry cough for the previous 2 weeks. Initial CT revealed bilateral miliary nodules surrounded by ground-glass opacity (GGO) and interlobular septal thickening, mainly distributed in the left lung. Bacterial pneumonia was suspected; thus, garenoxacin was prescribed. However, CT scan after treatment with garenoxacin revealed new consolidation superimposed on miliary nodules in the right lung. Contrarily, the GGO and interlobular septal thickening in the left lung were improved, but miliary nodules remained. Finally, cryptococci were detected in the lung specimen via bronchoscopy and those were also detected in cerebrospinal fluid, leading to the diagnosis of disseminated cryptococcosis. When performing bronchoscopy in patients treated with ibrutinib, cryptococcosis needs to be considered despite atypical chest CT findings.