Pattern of Clinical Presentation, Laboratory Findings and Mortality Risk Among Patients of Scrub Typhus in Western Himalayas.

OBJECTIVE To study the pattern of the clinical presentation, laboratory findings and mortality risk among patients infected by scrub typhus in Western Himalayan region of India. METHODS We studied all serologically confirmed cases of scrub typhus admitted to our hospital from July 2010 through December 2011. Presence of IgM antibodies to scrub typhus antigens by ELISA was considered as serological confirmation of the diagnosis. We observed the symptoms, signs, laboratory findings, risk factors for death from the time of admission till discharge/death. We performed bivariate and logistic regression analysis to look for independent risk factors for death. RESULTS Total 253 patients were studied. All patients came from rural areas. More than 2/3rd were women and below 50 years of age each. High grade fever (90%), chills and rigors (68%), conjunctival suffusion (50%), body aches (43%), headache (41%), myalgias (37%), abdominal pain (21%), lymphadenopathy (17%), splenomegaly (17%), cough (16%), altered sensorium (16%), vomiting (15%), hepatomegaly (13%) were main presenting features. Eschar was present in 112 (44%) patients. Transaminitis (49%); and abnormal renal functions (31%) were predominant biochemical abnormalities. All patients were empirically treated with doxycycline/azithromycin. Thirteen (5%) patients died. CONCLUSIONS In our region, rural women below 50 years of age presenting with high grade fever with or without eschar should be strongly suspected to be having scrub typhus. Renal dysfunction and altered sensorium are significant mortality risk factors (p < 0.05) and need to be identified at early stage to improve the treatment outcomes.