Presentation
History of previous renal transplant. Now septic.
Patient Data

Multiple nodules (some cavitating) in the left lower lobe

Multiple nodules (some cavitating) in the left lower lobe, with PET uptake. Previous CT 2 weeks ago (not shown) was unremarkable. Given the short interval, appearances likely secondary due to infection.

CT guided biopsy of left lower lobe nodule.
HISTOLOGY
MACROSCOPIC DESCRIPTION: A core of pale tan tissue measuring 8mm in length and 1mm in diameter and multiple fragments less than 1mm each measuring in aggregate 3 x 2 x 1mm.
MICROSCOPIC DESCRIPTION: Sections of lung biopsy shows alveolar spaces containing multiple rounded/ovoid to slightly irregular shaped yeast-like forms. They are of variable size and there appears to be a capsule. No obvious inflammatory reaction is noted. No granulomas and no acid fast bacilli are noted. No evidence of malignancy is identified.
DIAGNOSIS: Lung biopsy : Fungal elements seen. Appearance raises suggestion of Cryptoccoccus. Please correlate with microbiology.
Microbiology
Specimen site Left lung biopsy
Microscopy Fungal elements seen
Gram Stain ++ Polymorphs, No organisms seen
Culture + Cryptococcus neoformans
Case Discussion
Cryptococcosis has variable manifestations in the lung. This case demonstrates the scattered nodular pattern.
In a patient with previous transplant, the differential for multiple pulmonary nodules includes infection, metastases and post-transplant lymphoproliferative disorder.