Extrapulmonary tuberculosis is tuberculosis within a location in the body other than the lungs. This occurs in 15–20% of active cases causing other kinds of TB. These are collectively denoted as "extrapulmonary tuberculosis". Extrapulmonary TB occurs more commonly in immunosuppressed persons and young children. In those with HIV, this occurs in more than 50% of cases. Notable extrapulmonary infection sites include the pleura, the central nervous system, the lymphatic system, the genitourinary system and the bones and joints among others.