Abstract: SA-PO253
Bartonella Endocarditis Causing Immune Complex Mediated Glomerulonephritis
Session Information
- Trainee Case Reports - V
October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Reports
- 1202 Glomerular Diseases: Immunology and Inflammation
Authors
- Mukhtar, Hamid, Iowa Methodist Medical Center, Des Moines, Iowa, United States
- Mutneja, Anubha, Iowa Kidney Physicians, PC, Des Moines, Iowa, United States
Introduction
Bartonella is associated with subacute bacterial endocarditis. While vegetations are commonly seen, rarely there are cases of subacute endocarditis showing only valvular thickening. We describe one such case of bartonella endocarditis with immune complex mediated glomerulonephritis.
Case Description
A 63-year-old male with history of aortic bioprosthetic valve presented with fevers, chills and myalgias. On presentation, labs showed pancyctopenia- Hb 6.6 g/dL, ANC 1500 per mm3 and platelet 39 k/mm3. Creatinine was 3.8 mg/dL , urinalysis showed proteinuria 2+ along with hematuria. LDH was 293 U/L, haptoglobin 25 mg/dL, peripheral smear did not show any schistocytes. Serological work-up showed low C3 at 71 mg/dL, normal C4, negative ANA, positive c-ANCA (1:256) and positive PR-3 Ab. Bone marrow biopsy showed myeloid hyperplasia, reactive-appearing along with polyclonal expansion of plasma cells 10-20%. Renal biopsy showed endocapillary proliferation with no fibrinoid necrosis or cellular crescents. IF showed near full house immune complex deposition with granular, mesangial staining for IgG (2+), IgM (1+), C3 (2+), C1q (trace), kappa (2-3+) and lambda (1+). Infectious work-up showed positive titers for Bartonella Henselae, both IgG (>1:1024) and IgM (1:512), serum PCR was negative. TEE showed severe stenosis of the prosthetic aortic valve and patient was started on doxycycline for Bartonella endocarditis. Four weeks later, he was noted to have partial recovery in renal function but continued to be dialysis dependent given high fluid gains.
Discussion
Bartonella endocarditis can lead to immune complex mediated glomerulonephritis. Even with absence of characteristic vegetations, presence of positive antibody titers along with hypocomplementemia and immune -complex mediated GN, support the diagnosis of endocarditis. Bartonella PCR even though has high specificity, its sensitivity is only about 40-70%. Timely initiation of appropriate antibiotic therapy may improve renal outcome.