Clinical outcome and predictors of severity in scrub typhus patients at a tertiary care hospital in Chandigarh, India.

BACKGROUND & OBJECTIVES: Scrub typhus is an under-reported rickettsial illness caused by Orientia tsutsugamushi which is transmitted by trombiculid mites. Serious complications are not uncommon and multiorgan dysfunction may develop leading to death. Paucity of data on the clinical spectrum and determinants of aftermath may be contributing to higher mortality in the region. A prospective study was done to describe the spectrum of organ dysfunction in serologically confirmed cases of scrub typhus and document predictors of adverse outcomes. METHODS: This prospective study was carried out in patients diagnosed to have scrub typhus by IgM ELISA. The clinical features, investigations and complications among survivors were statistically compared to those in the deceased. Fisher's exact test, t-test and logistic regression have been applied where appropriate. RESULTS: The study population comprised of 123 patients. Majority of patients (62%) had one or more organ dysfunction. Ten patients (8.1%) did not survive. Complications documented were acute kidney injury (AKI) in 35%, hepatitis in 29.2%, acute respiratory distress syndrome (ARDS) in 26%, shock in 13%, meningitis in 5.7%, disseminated intravascular coagulation (DIC) in 2.6%, pancreatitis in 2.6% and myocarditis in 1.6%. Certain clinical features, biochemical parameters and complications had statistically significant correlation with the outcome. The mean SOFA score was considerably higher in those who did not survive. Interpretation &conclusion: Patients developing hepatic dysfunction, acute kidney injury and respiratory distress should be identified early and intensively monitored. The SOFA score can be utilized to assess the severity at admission and rapidly triage the sicker patients.