This case highlights the importance of considering murine typhus in patients presenting with respiratory symptoms, thrombocytopenia, and systemic signs of infection. Risk for typhus is especially high among patients with recent exposures to mice or fleas, or travel to endemic areas like Southeast Texas; however, most cases cannot identify discrete exposures.⁵ The clinical presentation of murine typhus can overlap with that of common bacterial and viral pneumonias, as well as with conditions like sepsis and DIC, potentially leading to misdiagnosis if it is not part of the differential.⁴ In cases where standard treatments for respiratory infections fail, reevaluation of the diagnosis and consideration of regional epidemiologic factors are essential.⁶

In conclusion, this case underscores the need for heightened awareness of zoonotic infections such as murine typhus, particularly in emergency and critical care settings where delayed recognition can adversely affect outcomes.

Dr. Johnson is PGY-2 in emergency medicine at University of Texas at Houston Medical Center.

Dr. Dyal is an assistant professor of emergency medicine at the Johns Hopkins University School of Medicine.

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