Cryptococcus neoformans osteomyelitis of the tibia: a case report and review of the literature

Abstract

Introduction: Osteomyelitis is a bone inflammation that can be related to various infectious agents. As with any other type of inflammation, the prevailing symptoms and signs may include redness, swelling, pain, and heat. Fungal osteomyelitis is rare and usually found in immune-compromised patients.

Case presentation: A non-human immunodeficiency virus immunocompromised Greek female patient, 82 years old, visited the emergency department due to a 3 day pain located mainly over the left tibia's anterior surface, accompanied by swelling and redness. There was also a subcutaneous lesion of her left breast. Medical history revealed that the patient had an unmasked close contact with pigeons, a main host of the disease. Initial x-ray imaging showed an osteolytic area in the upper third of the tibial diaphysis. The patient was admitted and underwent a computed tomography-guided biopsy. The specimen revealed a Cryptococcus neoformans infection of the bone and the breast. She was treated with 400 mg fluconazole twice a day for 3 weeks while in hospital and 200 mg twice a day upon discharge for 9 months. After that, she underwent surgical debridement because of lasting local irritation. She was closely monitored in our outpatient office, and in her last visit, 1 year after the initial admission, inflammatory signs had regressed vastly.

Conclusions: To our knowledge, this is the ninth cryptococcal osteomyelitis of the tibia to be recorded since 1974, and the most unusual finding was the bifocal nature of the infection, affecting both the tibia and the breast.

Keywords: Breast; Case report; Cryptococcus; Osteomyelitis; Tibia.

Fig. 1

Anteroposterior x-ray of the patient’s left tibia and the fibula. Initial x-rays upon arrival, indicating an osteolytic lesion of the diaphysis

Fig. 2

MRI axial view of the affected tibia, STIR sequence showing a high-signal, osteolytic-like lesion of the diaphysis

Fig. 3

CT-guided biopsy of the left tibia

Fig. 4

a–c Microscopic images of the bone and marrow specimen depicting the fungi in arrows

Fig. 5

Intraoperative images. a Debridement of the lesion. b Filling with bony allograft and 50 mg of amphotericin B powder

Fig. 6

a, b Images depicting the bone scintigraphy of both patient’s tibiae with the same perfusion and signal