Multifocal skeletal tuberculosis: bone scan appearances.

Bone scans are not generally required in the investigation of tuberculosis. The most common reason for the request is bone pain, which may precede the diagnosis of tuberculosis. The finding of multifocal areas of increased uptake on a bone scan may be due to a number of causes, the most common of which is metastatic bone disease. Therefore, there is a risk that those caused by tuberculosis may be misdiagnosed. We report six such bone scans occurring over 5 years which were found to be due to skeletal tuberculosis. Five patients were of Asian descent, four of whom had had bone biopsies confirming the presence of mycobacterium tuberculosis. The sixth patient, a Caucasian, had a bone biopsy which isolated mycobacterium bovis. Although skeletal tuberculosis is generally secondary to a primary pulmonary focus, all six patients had a normal chest X-ray.