The resurgence of tuberculosis in children is greatest in countries with high rates of HIV infection. The diagnosis of tuberculosis is often difficult and resources may be wasted in treating suspected cases who do not have the disease. Now researchers in South Africa (

) have assessed a rapid blood test. The ELISPOT test is an enzyme linked immunospot assay that detects T cells specific for Mycobacterium tuberculosis antigens not present in BCG or most environmental mycobacteria. Among 262 children with suspected tuberculosis 133 were categorised as having confirmed or highly probable tuberculosis. Of these 133, 110 had a positive ELISPOT test (test sensitivity 83%) and 73 (of 116 tested) had a positive Mantoux test (test sensitivity 63%). Among young children (<3 years old), children also infected with HIV, and children with malnutrition the sensitivity of the ELISPOT test was 85%, 73%, and 78% respectively whereas the Mantoux test was only 51%, 36%, and 44% sensitive. Among all children with tuberculosis combined ELISPOT and Mantoux testing was 91% sensitive. Among 13 children categorised as “not tuberculous” four had a positive ELISPOT test. The ELISPOT test is more sensitive than the Mantoux test for the diagnosis of tuberculosis in children. Using both tests gives a sensitivity of over …