Abstract: FR-PO0451
A Paws-itive Result: Rare Case of Bartonella Endocarditis with Associated Glomerulonephritis in an Adolescent with a Bioprosthetic Valve
Session Information
- AKI: Case Reports - TMA, Vasculitis, Immune-Mediated Injury, and Systemic Disease
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 102 AKI: Clinical, Outcomes, and Trials
Authors
- Mishra, Aparajita, West Chester Hospital, Westchester, New York, United States
- Mazo, Alexandra, Westchester Medical Center Health Network, Valhalla, New York, United States
- Sheth, Avni, Westchester Medical Center Health Network, Valhalla, New York, United States
Introduction
Infective endocarditis due to fastidious microorganisms should be considered in patients with renal manifestations. We present a rare pediatric case of Bartonella henselae subacute endocarditis associated with glomerulonephritis.
Case Description
A 14-year-old male with congenital heart disease and a bioprosthetic pulmonary valve presented with pleuritic chest pain and anuria after a year of progressive fatigue and weight loss. On admission he was febrile and fatigued with splenomegaly. Cardiac exam revealed a fixed split S2 and stable 2/6 systolic ejection murmur. Labs demonstrated microcytic anemia, thrombocytopenia, acute kidney injury, elevated inflammatory markers, microscopic hematuria, and proteinuria. Autoimmune evaluation showed positive ANA and hypocomplementemia. Echocardiogram demonstrated thickening of the pulmonary valve concerning for subacute infective endocarditis.
Despite negative blood cultures, blood genomic sequencing identified Bartonella henselae infection. Further history revealed recent kitten exposure. Antibiotics were transitioned from ceftriaxone/daptomycin to doxycycline and gentamicin for Bartonella subacute bacterial endocarditis.
Due to worsening non-oliguric AKI (peak Cr 3.7 mg/dL) with sub-nephrotic proteinuria, renal biopsy was performed and showed sclerosing glomerulonephritis with focal necrosis, severe interstitial fibrosis, and tubular atrophy, consistent with infective endocarditis–associated glomerulonephritis (IEAGN). Corticosteroids were initiated with improvement in renal function. He was discharged on a 12-week doxycycline course and steroid taper. Follow-up echocardiogram 2 months later showed improved pulmonary valve flow. His outpatient course was complicated by vasculitic rash and polyarthritis requiring steroid re-initiation. At 6 months, renal function improved though creatinine remained elevated at 1.35 mg/dL.
Discussion
IEAGN can mimic lupus and delay SBE diagnosis. Molecular testing identified Bartonella henselae infection after missed kitten exposure history. Despite targeted therapy, persistent AKI and new autoimmune symptoms developed, a rarely reported phenomenon.
Culture-negative endocarditis can delay diagnosis and targeted therapy. Molecular diagnostics enabled pathogen identification, while persistent IEAGN and autoimmune manifestations underscore the need for improved treatment strategies.