Thoracic cryptococcal osteomyelitis mimicking tuberculosis: A case report

BACKGROUND: Isolated cryptococcal osteomyelitis of the spine is extremely uncommon; there have been only seven cases identified in literature. The majority were originally misdiagnosed as tuberculosis. Here, we present a patient with cryptococcal osteomyelitis of the thoracic spine with associated fungal retinal deposits. CASE DESCRIPTION: A 45-year-old, type II diabetic female presented with a 5-month history of severe back pain. Her magnetic resonance imaging (MRI) revealed osteomyelitis involving the T4 vertebral body with epidural and prevertebral extension; notably, the intervertebral disc spaces were not involved. Although the fine-needle aspiration cytologic examination was inconclusive, the patient was empirically placed on antitubercular drug therapy. One month later, she became fully paraplegic. The MRI now demonstrated osteolytic lesions involving the T4 vertebral body with cord compression. She underwent biopsy of the T4 vertebral body and a transfacet T4 decompression with T2-T6 pedicle screw fixation. Culture and histopathological examinations both documented a cryptococcal infection, and she was placed on appropriate antifungal therapy. Notably, 3 weeks after surgery, she developed a sudden loss of vision loss due to retinal fungal endophthalmitis. She recovered vision in one eye after the administration of intravitreal voriconazole but lost vision in the other eye despite a vitrectomy. Over the next 8 months, she gradually recovered with motor function of 4/5 in both lower extremities without evidence of recurrent disease. CONCLUSION: Cryptococcal infection should be among the differential diagnostic considerations for patients with vertebral osteomyelitis. Notably, diagnostic delay can lead to devastating neurological deficits and involvement of other organ systems.