Scrub typhus: an important differential diagnosis of acute and subacute febrile illness

Abstract

Background: Scrub typhus is an acute febrile illness caused by an obligate intracellular organism Orientia tsutsugamushi. The name is derived from the vegetation type that usually harbors the vectors. Scrub typhus is endemic to a distinct region, the tsutsugumashi triangle, which include Japan, Taiwan, China and South Korea.Scrub typhus is known to occur all over India including the north hilly areas. Cases of scrub typhus from State of Bihar are few and that too reported from hospitals of other states. Objectives: This study was undertaken to determine the prevalence of scrub typhus in patients presenting with acute and subacute febrile illness, to study the clinical profile and to assess the utility of Enzyme-Linked Immunosorbent Assay for sero diagnosis of scrub typhus.Methods: We undertook a retrospective , cross sectional study at a tertiary care super speciality teaching hospital in over a period of 18 months from January 2016 to July 2017. Patients presenting with acute and sub-acute undifferentiated febrile illness, admitted in department of general medicine were included in the study Results: Out of total 144 admitted patients of acute and sub-acute undifferentiated febrile illness, 18 were found to be suffering from scrub typhus. It was 12.5% of total cases of undifferentiated febrile illness. The disease was prevalent in all age group including old age. 61% of patients with scrub typhus were female and 39% were male. All 18 patients had fever as chief complaint. Other common complaints were chills, myalgia, abdominal pain and yellow discoloration of urine. Eschar were found in five patients.Conclusions Early diagnosis is essential to reduce the morbidity and mortality in scrub typhus. Laboratory diagnosis is based mainly on serological tests.