Differential Diagnosis, Investigations, and Treatment
Given these findings, empiric antibiotic treatment was started for
suspected brain abscess, but as metastatic disease could not be ruled
out, brain and transbronchial biopsies were performed. Histopathologic
examination revealed a brain abscess with both budding yeast and
filamentous bacilli (Figure 1), and cultures of the brain biopsy grewR. mucilaginosa and N. abscessus . Lung biopsy was
unremarkable. Due to the rare, invasive fungal infection in the absence
of known risk factors such as CVC, work-up for immunocompromising
conditions was undertaken, eventually revealing a diagnosis of CVID.
Empiric antibiotic therapy was thus replaced with meropenem,
trimethoprim-sulfamethoxazole, and liposomal amphotericin B.
Amphotericin B associated electrolyte abnormalities prompted a switch to
voriconazole, but unfortunately, despite several weeks of intensive
medical therapy, the patient’s respiratory status continued to decline
and she was transferred to the ICU for mechanical ventilation.