Blastomycosis, a fungal infection caused by inhalation of aerosolized Blastomyces dermatitidis and Blastomyces gilcristi conidia, has had an increased incidence in the United States. Though blastomycosis typically presents with respiratory symptoms, up to ten percent of cases of disseminated blastomycosis have Central Nervous System involvement. We present a case of hydrocephalus secondary to disseminated blastomycosis meningitis.

A 38-year-old male presented with a three-month history of headaches, dizziness, and left sided weakness. Patient was started on empiric coverage for bacterial meningitis, however this was discontinued following unrevealing initial gram stain of cerebrospinal fluid (CSF). Brain imaging revealed communicating hydrocephalus with diffuse leptomeningeal enhancement. CT Abdomen and Pelvis revealed left lower lobe mass. The pulmonary biopsy culture, fungal PCR, and Mycobacterium tuberculosis PCR were negative. CSF studies revealed negative Blastomycosis antibody. Patient was discharged on 4-drug therapy for tuberculosis and steroid taper outpatient. Ventriculoperitoneal Shunt (VPS) placed for management of symptomatic hydrocephalus.

Six months following initial presentation, patient was admitted for recurrent gait instability and dizziness and new abdominal pain. VPS series confirmed intact tubing.  CT Abdomen-Pelvis ordered for patient’s complaints of abdominal pain, which revealed mesenteric and peritoneal nodularity. Omental biopsy was consistent with blastomycosis. Subsequent dural biopsy showed no fungal organisms on AFB or GMS staining. Patient’s symptoms improved following initiation of amphotericin-B therapy and patient was discharged to inpatient rehabilitation.

A high index of suspicion should be maintained for blastomycosis in cases of meningitis in endemic areas. CSF and tissue cultures often have low sensitivity for blastomycosis. Practitioners in endemic regions must maintain a high index of suspicion in cases of meningitis of unclear etiology and search for alternative sites of disseminated disease for histopathological sampling to support diagnosis.