LAUSR

Background Disseminated cryptococcosis is a well-characterized complication in immunocompromised patients with cryptococcal pneumonia or meningitis; however, isolated cryptococcal osteomyelitis is a rare entity that occurs in approximately 5% of patients with cryptococcosis. Cryptococcal osteomyelitis in the head and neck region is extremely rare. To the best of our knowledge, no cases of cryptococcal osteomyelitis affecting only the zygomatic bone have been reported to date. Case presentation A 78-year-old man without other comorbidities presented with progressive swelling of the right cheek along with pain and trismus. Clinical examination revealed a tender swelling in the right zygomatic region; the maximal mandibular opening was about 2 cm. Laboratory data showed mildly elevated inflammatory indices (C-reactive protein: 0.45 mg/dL; erythrocyte sedimentation rate: 35 mm/h). Computed tomography showed a 30-mm-diameter lesion at the right zygomatic arch. A part of the lesion has extended to the subcutaneous area of the cheeks with signs of bone destruction and surrounding contrast effects. Histopathological examination of fine-needle aspirate and needle biopsy showed cryptococcus. Furthermore, culture of the aspirate showed growth of Cryptococcus neoformans . No evidence of any other site involvement was observed. Therefore, the patient was diagnosed with isolated cryptococcal osteomyelitis and was initiated on fluconazole therapy. The treatment was effective, and all symptoms were resolved in 4 weeks. Fluconazole therapy was stopped after 6 months. There are no signs of recurrence as of 15-month follow-up. The patient has no cosmetic abnormalities or sequelae. Conclusions Fine-needle aspiration cytology, needle biopsy, and fungal culture were useful for definitive diagnosis. Immunocompetent patients with isolated osteomyelitis may be cured with oral fluconazole alone.