Scrub typhus with longitudinally extensive transverse myelitis

Abstract

Scrub typhus is a febrile illness caused by Orientia tsutsugamushi bacteria. It is endemic to a part of world known as the “tsutsugamushi triangle” extending from northern Japan and far-eastern Russia in the north, to northern Australia in the south, and to Pakistan and Afghanistan in the west 1–2 . Scrub typhus has been reported from many parts of India including Himachal Pradesh 3 . The disease is characterized by fever, headache, myalgia, cough, suffused conjunctiva and gastrointestinal symptoms. It is transmitted to humans through the bite of the larval trombiculid mites (commonly called chiggers). An eschar at the site of chigger bite pathognomonic and is seen in 40% patients of scrub typhus 4 . There can be presence of regional lymphadenopathy/generalized lymphadenopathy, maculopapular rash and splenomegaly. The severity of the symptoms varies widely in this disease. The disease is characterized by focal or disseminated vasculitis and perivasculitis which may involve the lungs, heart, liver, spleen and central nervous system 1–2 . The overall histological picture of scrub typhus in the central nervous system is best described as a meningoencephalitis. Dissemination of bacteria from the periphery to the central nervous system is hematogenous. Orientia tsutsugamushi is frequently found in circulating mononuclear cells during naturally acquired infection. There is prolonged microbial survival in leukocytes, and phagocyte-facilitated infection could play a role in invasion of central nervous system 5 . Detection of O. tsutsugamushi by pooled antigen ELISA has shown very good sensitivity (94%) and specificity (91%) 6 . The occurrence of various neurological manifestations in scrub typhus has been well documented in literature but its association with longitudinally extensive transverse myelitis (LETM) has not been reported. We present a case of scrub typhus with LETM that improved after treatment.