Nonoperative management for disseminated spinal blastomycosis with extensive lytic destruction in a 35-year-old male: illustrative case.

backgroundThe authors describe the case of a 35-year-old male who presented with back pain and painful masses on his upper extremities. He had a known sacral lesion identified 1 year prior at an outside facility, suspected to be coccidioidomycosis on biopsy, but the workup was not completed because the patient left against medical advice and was lost to follow-up. Computed tomography (CT) and magnetic resonance imaging revealed lytic destructive lesions involving the calvaria, thoracolumbar spine, and sacrum, concerning for an active and disseminated infection. Sacrum and right-hand biopsies and culture results from both revealed the growth of Blastomyces dermatitidis. With the exception of limitations due to pain, the patient was neurologically afocal and ambulatory. His pain descriptions were biological in nature rather than mechanical. He was not placed on spinal precautions, and surgery was deferred; he was treated medically with inpatient intravenous antifungals and long-term oral therapy after discharge. OBSERVATIONS: The patient's back pain was resolved at follow-up, and despite extensive lytic destruction demonstrated on CT imaging at initial assessment, he was found to have good bony remodeling at his affected levels, with no neurological deficits. LESSONS: This case illustrates the value of physical examination and symptomatology in surgical decision-making for disseminated fungal infections of the spine, even when imaging studies compellingly suggest instability. https://thejns.org/doi/10.3171/CASE24204.