Tuberculin reactivity and the effect of serum antibodies to PPd in tuberculosis

ABSTRACT

This study included 150 patients complaining of active pulmonary T.B/ and 16 healthy controls. They were subjected to history taking and clinical examination radiological examination and classification according to the national tuberculosis association USA [1961]; sputa were examined for acid fast bacilli; test and haemagglutination technique to detect the circulating anti PPD antibodies. There was a reverse correlation between the level of dermal reactivity to PPD and serum level of anti- PPD antibodies in the patients of the study. Titre of anti PPD- antibodies could differentiate tuberculin negative patients with active disease [high anti PPD antibodies level] from Tuberculin negative healthy controls [absent anti- PPD antibodies]. Thus detection of anti- PPD antibodies may be of diagnostic value in suspected tuberculosis disease with energy or hyporeactivity to PPD. After 2 months of antituberculus therapy, there was a significant increase of the diameter of their tuberculin skin, and concomitant drop in their serum level of anti PPD antibodies of patients especially for those with initial tuberculin negative reactions