In Search of Scrub Typhus: A Prospective Analysis of Clinical and Epidemiological Profile of Patients from a Tertiary Care Hospital in New Delhi

Introduction: Scrub typhus is a febrile illness caused by Orientia tsutsugamushi which is transmitted by the larval stage of trombiculid mites. It has varied manifestations ranging from mild disease to fatal illness. The classical manifestations include fever, rash, lymphadenopathy and eschar. Serology is the preferred diagnostic tool with indirect immunofluorescence assay (IFA) as the current gold standard. Material & Methods: A total of 229 clinically suspected cases of Scrub typhus from 15th of October 2013 to 15th of October 2015 were enrolled in the study. Clinical, epidemiological and laboratory data of the patients were collected and analysed. The method for diagnosis was IgM immunofluorescence assay. Results: A total of 33 cases (14.4%) of scrub typhus were detected. Most of the cases (87%) presented in the months of September to November. Fever of >39 ̊C was seen in all 33 cases. Rash and eschar were seen in 24.2% and 18.2% cases, respectively. Lymphadenopathy (18.2%), hepatomegaly (48.5%), splenomegaly (21.2%) and icterus (15.2%) were seen in some cases. Pulmonary manifestations were noted in 69.7% of cases. Acute kidney injury (18.2%), encephalitis (21.2%), and myocarditis (15.15%) were the other complications observed. Common haematological abnormalities noted in patients of scrub typhus were anaemia (45.6%), leucocytosis (45.6%), thrombocytopenia (48.5%) and transaminitis (54.5%). 10 cases were treated by azithromycin while doxycycline was used for treatment in 28 cases. Conclusion: The nonspecific symptoms and lack of classical manifestations make the diagnosis of scrub typhus difficult. There is a definite need to increase awareness and heighten the suspicion, especially in the light of increasing number of patients presenting with atypical manifestations.