[Widal reaction and phenotypes in children with typhoid fever (preliminary study)]

Recognition of genetic heterogeneity in typhoid fever patients might allow studies on the behaviour of definite cohorts regarding this infection, which would be important for clinical and epidemiological purposes. Under the hypothesis that agglutinins response (Widal test) is a suitable phenotype for this objective, associations between results of this response at admission (positive and negative) and clinical and hematological variables were explored in 91 children with bacteriologically confirmed typhoid fever, admitted to a metropolitan hospital at Santiago, Chile, during 1981-82 period. Association between gender and negative Widal test was found in males when this test was performed during the third week of disease (OR = 10, p = 0.52) as well as a tendency of females to express figures below the mean for total WBC count in patients older than 10 years (OR = 2.43, p = 0.019) and for neutrophils (%) in younger than this age when the Widal test was negative in the latter (OR = 10, p = 0.016). These preliminary findings suggest that Widal test and gender might interact for determining the presumptive heterogeneity in this children group.