Identification of typhoid fever and paratyphoid fever cases at presentation in outpatient clinics in Jakarta, Indonesia.

In Jakarta, Indonesia, over 80% of patients with typhoid fever or paratyphoid fever are treated in outpatient settings. In a community-based prospective passive surveillance study, we identified 59 typhoid, 23 paratyphoid fever and 259 non-enteric fever outpatients, all blood culture-confirmed. We compared their symptoms with the aim of developing a clinical prediction rule that may help direct empirical antibiotic treatment to cases with suspected (para)typhoid fever, rather than all febrile patients, or refer patients for additional diagnostic tests. Paratyphoid fever (Salmonella paratyphi A) could not be distinguished clinically from typhoid fever. Decisions on empirical antibiotic treatment and advice on hygiene measures in patients with suspected (para)typhoid fever should take into account chills and absence of cough in the first week of fever and delirium in the second week of illness. This prediction rule increases the likelihood of (para)typhoid fever from 1:10 in the first week to, at most, 2:3 in the second week of a febrile illness. However, we were not able to propose a robust clinical prediction rule that could be used as absolute screening method for decisions on additional diagnostic tests, because of the low sensitivity of presenting symptoms in (para)typhoid fever.