C69-01 Rickettsia Typhi - A Severe Case of Pneumonia With Sepsis in a Non-Endemic Region of the US

Abstract Introduction Typhus is an uncommon infection caused by the gram-negative bacteria Rickettsia Typhi. Transmission results from contact with vectors such as fleas, ticks, and mites. The disease survives via household pets and rodent reservoirs, and is endemic to warmer climates like the southwestern US, Mexico, and Latin America. Today, human cases are uncommon due to diminished contact with rodent species, making it difficult to diagnose outside of endemic areas. We highlight a case of a patient’s presenting to an intensive care unit in Detroit, Michigan with severe pneumonia secondary to typhus. Case Presentation A previously healthy 57-year-old male visiting from California presented to a Detroit emergency department with headache, fever, dyspnea, and chills. The patient was tachycardic and hypotensive, with tachypnea but no initial oxygen requirement. Chest x-ray demonstrated diffuse bilateral interstitial and airspace opacities. Sepsis treatment was initiated with antibiotics for community acquired pneumonia (ceftriaxone and azithromycin). His oxygen requirements rapidly escalated over 24 hours, ultimately requiring near-maximal heated high flow nasal cannula. During admission, multi-system organ damage was evidenced by AKI, transaminitis, mildly elevated troponins and BNP, and thrombocytopenia. The patient underwent a broad workup of infectious and non-infectious etiologies of respiratory failure without significant positive findings. It was subsequently discovered that the patient’s neighbor had recently been treated for murine typhus. The patient reported owning one dog and one indoor/outdoor cat as potential reservoir exposures. Rickettsial serologies were obtained, and doxycycline was started. The patient markedly improved and was ultimately weaned from supplemental oxygen. Rickettsial serologies returned positive after discharge (anti-rickettsial typhi IgG titer 1:64, IgM titer 1:256). Discussion Typhus classically manifests with headache, fever, chills, and a maculopapular rash. Rarely, untreated typhus can lead to sepsis and end-organ damage such as fulminant hepatitis, myocarditis, renal failure, pneumonia, and seizures. Mortality rates of murine typhus remain low, likely in part due to the rarity of severe cases, and its timely recognition in endemic regions. This case represents a rare instance of typhus manifesting as sepsis with pneumonia as the predominant clinical syndrome resulting in critical illness. Adding to the novelty, this patient demonstrated no rash at any point in his disease course. Ultimately, suspicion for typhus changed this patient's clinical course significantly. Given the variability of clinical presentation and possible mimicry of many other disease processes, a thorough travel and exposure history is paramount to making the diagnosis of murine typhus. This abstract is funded by: None