Usefulness of skin testing with mycobacterial antigens in children with cervical lymphadenopathy

One hundred twenty-three children with chronic cervical lymphadenopathy were skin-tested with purified protein derivative (PPD)-B (Mycobacterium intracellulare), PPD-Y (Mycobacterium kansasii), PPD-G (Mycobacterium scrofulaceum) (nontuberculous mycobacterial antigens (NTMags)) and PPD-T (Mycobacterium tuberculosis). Children with culture-confirmed mycobacterial disease had significantly larger reactions to NTMags and were 6 times more likely to have PPD-B responses of greater than or equal to 10 mm than those with negative microscopy/culture results. Children with acid-fast bacilli present in clinical specimens but with negative culture results were 3 times more likely to have greater than or equal to 10 mm induration to PPD-B than those with negative microscopy/culture results. In all groups except those with culture-confirmed M. tuberculosis, responses to PPD-T were significantly smaller than those to the NTMags. We conclude that NTMags, particularly PPD-B, may be useful in diagnosing childhood mycobacterial cervical adenopathy; however, their usefulness in distinguishing disease caused by M. tuberculosis from that resulting from other mycobacteria is unknown.