BCG osteomyelitis as a rare cause of mediastinal tumor in a one-year-old child.

A one-year-old child with BCG osteomyelitis of the upper spine is reported. The child was admitted because of viral infections of the upper respiratory tract. A lateral x-ray examination of the lung showed what was thought to be a mediastinal tumor. The preoperative diagnostic problems are discussed, because the etiology in our case was unknown until the histological report arrived. The knowledge of the complication, of osteomyelitis after vaccination, is small although the first case was published more than 40 years ago. Since then about 300 cases have been reported in the literature. The disease is seen in the first five years of life in otherwise healthy children. Most cases are localized near the epiphysis of the long bones. A localization in the spine, as described in our case, has been published only three times before. The highest frequency of BCG osteomyelitis is reported in Finland and Sweden with about 40 cases per 1 million vaccinations.