Scrub typhus: A prospective, observational study during an outbreak in Rajasthan, India.

Background: Scrub typhus, a potentially fatal rickettsial infection, is common in India. It usually presents with acute febrile illness along with multi-organ involvement caused by Orientia tsutsugamushi. As there was an outbreak of scrub typhus in the Hadoti region of Rajasthan and there is a paucity of data from this region, we studied this entity to describe the diverse epidemiological, clinico-radiological, laboratory parameters and outcome profile of patients with scrub typhus in a tertiary care hospital.

Methods: In this descriptive study, we included all patients with an acute febrile illness diagnosed as scrub typhus by positive IgM antibodies against O. tsutsugamushi, over a period of 4 months (July to October 2014). All relevant data were recorded and analysed.

Results: A total of 66 (24 males/42 females) patients were enrolled. Fever was the most common presenting symptom (100%), and in 67% its duration was for 7-14 days. Other symptoms were breathlessness (66.7%), haemoptysis (63.6%), oliguria (51.5%) and altered mental status (39.4%). The pathognomonic features such as eschar (12%) and lymphadenopathy (18%) were not so common. The commonest radiological observation was consistent with acute respiratory distress syndrome. Complications noted were respiratory (69.7%), renal (51.5%) and hepatic dysfunction (48.5%). The overall mortality rate was 21.2%.

Conclusions: Scrub typhus has emerged as an important cause of febrile illness in the Hadoti region and can present with varying clinical manifestations with or without eschar. A high index of suspicion, early diagnosis and prompt intervention may help in reducing the mortality.