Large-Vessel Pseudoaneurysms as a Vascular Complication of Scrub Typhus in an Immunosuppressed Patient

Scrub typhus is a mite-borne rickettsial infection endemic in many parts of India and typically causes small-vessel vasculitis; large-vessel involvement is rare. We report a 52-year-old immunosuppressed man on long-term tofacitinib who presented with prolonged fever, weight loss, and systemic inflammation, and was found to have multiple pseudoaneurysms involving the abdominal aorta, carotid, and popliteal arteries, along with pulmonary nodules and necrotic lymphadenopathy. Extensive evaluation for tuberculosis, fungal infections, and bacterial endocarditis was negative, with no response to broad-spectrum antimicrobials or antitubercular therapy. Serology for scrub typhus was positive following identification of travel to an endemic area, and doxycycline led to rapid clinical and biochemical improvement. Selected pseudoaneurysms were managed surgically and endovascularly with good outcomes. This case highlights scrub typhus as a rare cause of large-vessel pseudoaneurysms in immunosuppressed patients in endemic regions.