Factors Associated with Encephalopathy in Patients with Salmonella enterica Serotype Typhi Bacteremia Presenting to a Diarrheal Hospital in Dhaka, Bangladesh

To characterize clinical correlates of typhoid fever-associated encephalopathy, we performed a retrospective chart review of patients with Salmonella enterica serotype Typhi bacteremia who were hospitalized at the International Centre for Diarrhoeal Disease Research, Bangladesh, from February of 2009 to June of 2011. Of 207 patients bacteremic with Salmonella Typhi who were >= 5 years of age, we identified 43 (21%) patients with encephalopathy. Univariate analysis revealed that patients with encephalopathy more often presented at ages of 10-24 years and had severe dehydration, low oxygen saturation, high respiratory rate, low leukocyte count, low platelet count, and Widal flagellar H agglutinin (TH) titer >= 1:640 compared with typhoid patients without encephalopathy. Multivariate analysis using logistic regression showed that age, dehydration, leukocyte count, and Widal TH titer were independently associated with encephalopathy. Our findings suggest that age, severity of disease, and immune responses are associated with encephalopathy during Salmonella Typhi bacteremia, perhaps reflecting the impact of prominent inflammatory responses.