Eschar: a diagnostic beacon in acute undifferentiated febrile illness

A 35-year-old previously healthy man from rural eastern India presented with a five-day history of high-grade intermittent fever accompanied by severe myalgia, headache, nausea and recurrent vomiting. He denied respiratory, urinary or gastrointestinal symptoms. Initial examination revealed no rash, lymphadenopathy or organomegaly. Laboratory findings showed normocytic anaemia, neutrophilic leukocytosis and elevated transaminases. Rapid tests for malaria and dengue were negative; abdominal ultrasonography and chest radiography were normal. Given the persistent fever and epidemiological background, our team explained the hallmark appearance of an eschar to the patient and his relatives using a clinical image from our previous publication in the QJM, requesting them to report if a similar lesion was noticed.1 During reassessment the following morning, the patient’s elder brother pointed out a small, painless lesion on the left lower abdomen. Examination confirmed a well-defined ulcer with a central black crust consistent with an eschar (Figure 1). Oral doxycycline (100 mg twice daily) was initiated without delay. Orientia tsutsugamushi IgM returned strongly positive, and PCR of an eschar specimen targeting the groEL gene confirmed the diagnosis of Scrub Typhus. The patient demonstrated rapid clinical improvement with complete defervescence within 48 h of doxycycline therapy.