A simple validated prediction rule to diagnose typhoid fever in Turkey.

The goal of this study was to develop a simple prediction rule for the diagnosis of typhoid fever. A model for the prediction of patients with typhoid fever at hospital admission was derived and validated by assigning weighted point values to independent predictive factors associated with a diagnosis of typhoid fever at hospital admission. Patient demographic, clinical and laboratory variables were used to compare patients with blood culture-confirmed typhoid fever with patients with fever of unknown origin. The model was derived and validated in two separate cohorts of patients from Dicle University Hospital in Diyarbakir, Turkey. A total of 371 patients were enrolled. A diagnostic index score was created using seven independent predictive factors associated with typhoid fever at hospital admission: age <30 years, abdominal distention, confusion, leukopenia, relative bradycardia, positive Widal test and a typhoid tongue. A clinical prediction rule helped to differentiate patients with typhoid fever.