Case Presentation: This case report outlines the clinical course of a previously healthy 25 year old female who presented to the emergency department with a 2 week history of myalgia, high grade fever, and pain in palms and soles of her feet. Upon presentation to the patient’s local ER, her clinical condition rapidly deteriorated, and she was transferred to Trinity Regional Medical Center. There, Cardiac computed tomography angiography was negative for pulmonary embolism but did reveal severe pulmonary edema. She exhibited cardiomyopathy with cardiomegaly, acute hypertension, and a BNP of 6880. She was empirically started on vancomycin, ceftriaxone, intubated, and emergently airlifted to Mercy Medical Center Des Moines. Upon arrival, labs were pertinent for leukocytosis, elevated CRP, anemia, metabolic acidosis, transaminitis and thrombocytopenia with platelet count of 44. 1 unit of platelets was transfused, and peripheral blood smear ruled out Thrombotic Thrombocytopenia Purpura. A lumbar puncture was ordered and acyclovir added prophylactically. Screening antinuclear antibodies were negative. Patient self extubated and continued to exhibit high fevers up to 104 with worsening shock and severe headache. Despite broad-spectrum antibiotic therapy, antivirals, and supportive care, her symptoms persisted. Serological tests for common infectious agents, including viral, bacterial, and parasitic pathogens were negative. An expanded infectious disease workup was negative for over 25 other infectious etiologies. A gene analysis and blood sample for Karius microbial DNA Sequencing PCR were sent for analysis. At this time, she was still requiring 2 vasopressors and supplementary oxygen in the ICU. Initial CSF biofire and blood cultures were negative for bacterial or viral etiologies. The Karius blood PCR revealed Rickettsia typhi, Bacteroides vulgarus, and B. fragilis.
Discussion: This case emphasizes the importance of maintaining a high index of suspicion for less common pathogens. This patient was diagnosed with Rickettsia typhi and exhibited severe presentation including neurologic dysfunction, cardiomyopathy, pulmonary edema, hepatic dysfunction, and thrombocytopenia. Timely diagnosis and appropriate treatment with doxycycline and metronidazole resulted in a successful outcome for this patient.
Conclusions: Rickettsia typhi is transmitted primarily through fleas and is the causative agent of murine typhus. The patient was exposed while living in a home in rural Iowa with unvaccinated pets that go outside. Bacteroides species are anaerobic gram-negative bacteria commonly found in the human gastrointestinal tract and is likely an incidental translocation identified in a highly sensitive PCR test. Treatment with doxycycline was initiated for Rickettsia typhi, and metronidazole to target the Bacteroides infection. The patient responded favorably to this combination therapy, with a rapid resolution of her symptoms and fever.
