A case of typical eschar and severe thrombocytopenia in a child with Tsutsugamushi Disease

<title>Abstract</title> <p>We report a case of a 5-year-old boy who presented with high fever, generalized petechiae, and severe thrombocytopenia. He was initially misdiagnosed with immune thrombocytopenic purpura. A careful physical examination revealed a characteristic eschar on the left forearm. Combined with a history of outdoor activity, a diagnosis of tsutsugamushi disease (scrub typhus) was suspected and later confirmed by positive Orientia tsutsugamushi IgM and metagenomic next-generation sequencing (mNGS) of the blood. Antibiotic therapy was switched to azithromycin, resulting in rapid defervescence and normalization of platelet count. This case highlights the importance of considering tsutsugamushi disease in the differential diagnosis of fever with thrombocytopenia, the critical role of meticulous skin examination in identifying the pathognomonic eschar, and the utility of mNGS in rapid etiological diagnosis, especially in atypical presentations.</p>