18F-FDG PET as a monitoring tool to assess treatment response in bilateral adrenal histoplasmosis.

A 60-year-old woman with clinical and biochemical features suggestive of adrenal insufficiency was found to have bilateral adrenal masses on CT scan and was subjected to F-FDG PET scan. The scan showed hypermetabolic mediastinal nodes in addition to intense tracer uptake in bilateral adrenal masses. CT-guided adrenal biopsy grew Histoplasma capsulatum on Sabouraud dextrose agar culture. A second F-FDG PET scan after 6 months of appropriate antifungal therapy showed a significant decrease in intensity of uptake consistent with the clinical outcome.