Delayed hypersensitivity to specific antigen and hetrologous PPD antigen in patients infected with Schistosoma mansoni and/or Schistosoma haematobium.

181 cases with schistosomiasis were skin tested with S. mansoni antigen and tuberculin (PPD) after complete clinical and parasitological examination. Their results were compared to a control group of 89 non bilharzial cases. The positivity of tuberculin reaction was found to be less frequent in schistosomiasis (37.5%) when compared to non schisto. controls (55.0%). This low reactivity was more manifest in the advanced stages of the disease. The delayed skin reaction with S. mansoni antigen was seen in 52.4% of schisto. cases while non of the control showed any positivity. There are more delayed skin test positives with the advance of the disease.