Objective:

NA

Background:

Bartonella quintana is a fastidious gram-negative bacillus historically associated with trench fever and transmitted by body lice or animals. It is a rare but significant cause of culture-negative infective endocarditis, often presenting with nonspecific symptoms and delayed diagnosis due to slow growth in standard cultures. Neurological complications like acute ischemic stroke are uncommon but clinically relevant. This case highlights the diagnostic challenges and neurological impact of B. quintana endocarditis in an immunocompetent patient.

Design/Methods:

A 70-year-old male with a history of right craniotomy and hypertension presented with sudden right-sided weakness and dysarthria. He was outside the window for thrombolysis, and thrombectomy was not indicated. MRI revealed an acute infarct in the left parietal lobe, suggestive of a cardioembolic event. Transthoracic echocardiogram showed anterior mitral valve echodensities with mild regurgitation. Transesophageal echocardiography confirmed a 1.0 x 0.8 cm vegetation with severe mitral regurgitation.

CT angiography incidentally detected a 1 cm hypoattenuating lesion in the right palatine tonsil; biopsy showed benign cysts. Blood cultures initially grew gram-positive coryneform rods, but further cultures remained negative. Given suspicion for culture-negative endocarditis, plasma next-generation sequencing (Karius test) identified Bartonella quintana. The patient’s pet cat was considered a possible zoonotic source.

Treatment included doxycycline and rifampin for three months. A complete heart catheterization was performed in preparation for potential mitral valve surgery. He was discharged to inpatient rehabilitation on aspirin and statins for stroke prevention, with infectious disease follow-up for serological confirmation.

Results:

NA

Conclusions:

Bartonella quintana should be included in the differential for culture-negative endocarditis, especially in patients with embolic strokes. Next-generation sequencing is a valuable diagnostic tool that enables early detection and targeted therapy, potentially improving outcomes.