A study of parents of 50 allergic children has been presented. A history of personal or family allergy was elicited in 20 mothers and 23 fathers, but bilateral histories were found in only 11. Scratch tests were performed on these parents and on a group of 44 adults free of allergy.
The children themselves were scratch-positive in 46 (92%) of the cases. The parents were scratch-positive in 70% (mothers) and 72% (fathers) of the cases. The presumably nonallergic comparison group of adults was positive in one (2.2%) case.
Of the parents as individuals, both history and scratch test indicated allergy in 56 (56%) of the cases (36 allergic subjects were positive and 20 "nonallergic" subjects were negative). Disagreement occurred in 44 cases, of which 37 were scratch-positive although clinically "nonallergic." In the remaining seven, verification of clinical allergy was lacking. This 7% compares favorably with the 8% of children known to be allergic in whom verification by scratch test was not demonstrated.
Using history and scratch tests as criteria for the presence of allergy, the results indicate that in 50 allergic children, 66% possessed evidence for familial allergy in both parents, 28% in one parent, and 6% in neither parent.