A 41-year-old man underwent skeletal scintigraphy due to chronic pain in the left foot and polyarthralgia. He was taking medication for gout and had previously had sarcoidosis, for which he had received corticosteroids and other therapy that was discontinued 4 years ago. Scintigraphy revealed a mass in the shaft of the left humerus that, according to biopsy, was an asymptomatic osteomyelitis caused by Mycobacterium avium. The shaft of the left humerus is an uncommon site for tuberculous osteomyelitis. A viable fistula remained after the biopsy that persisted despite pharmacologic treatment with ethambutol, rifabutin and clarithromycin. Four months later, sequestrectomy was performed with insertion ofgentamicin-impregnated beads, which resulted in rapid resolution. The foot pain resolved spontaneously. The incidence of bone tuberculosis has increased over the last 2 decades. The most commonly affected sites are the spine and large joints. Infection with M. avium is sometimes involved. Because of the increasing incidence it is important to include mycobacterial infections in the differential diagnosis of focal bone lesions, especially when standard cultures are initially negative.

A 41-year-old man underwent skeletal scintigraphy due to chronic pain in the left foot and polyarthralgia. He was taking medication for gout and had previously had sarcoidosis, for which he had received corticosteroids and other therapy that was discontinued 4 years ago. Scintigraphy revealed a mass in the shaft of the left humerus that, according to biopsy, was an asymptomatic osteomyelitis caused by Mycobacterium avium. The shaft of the left humerus is an uncommon site for tuberculous osteomyelitis. A viable fistula remained after the biopsy that persisted despite pharmacologic treatment with ethambutol, rifabutin and clarithromycin. Four months later, sequestrectomy was performed with insertion of gentamicin-impregnated beads, which resulted in rapid resolution. The foot pain resolved spontaneously. The incidence of bone tuberculosis has increased over the last 2 decades. The most commonly affected sites are the spine and large joints. Infection with M. avium is sometimes involved. Because of the increasing incidence it is important to include mycobacterial infections in the differential diagnosis of focal bone lesions, especially when standard cultures are initially negative.

A 75-year-old man and a 53-year-old woman had longstanding joint pain, for which they had been treated with NSAIDs. When the symptoms worsened, a thorough diagnostic investigation was conducted that revealed myeloproliferative bone-marrow disorders in both patients. The man, who had polyarticular gout secondary to chronic myelomonocytic leukaemia, was able to maintain control of his joint pain with medical treatment. In the woman, with a history of stable joint pain due to polyarthritis, deterioration of the symptoms and the development of pancytopaenia led to a diagnosis of acute lymphocytic leukaemia; she died after receiving multiple courses of chemotherapy. The possibility of an underlying malignancy should be considered in patients with atypical symptoms in the locomotor system, an unexpected course or anomalous secondary symptoms.