title: Necrotizing glomerulonephritis caused by Bartonella henselae endocarditis.
abstract: Glomerulonephritis secondary to endocarditis is uncommon and usually associated with valvular infection by blood culture-positive bacteria. We report 3 cases of necrotizing glomerulonephritis associated with culture-negative endocarditis caused by Bartonella henselae. Two of the patients presented with renal abnormalities and were investigated for endocarditis after results of renal biopsy. All 3 patients had an immune complex-mediated necrotizing and crescentic glomerulonephritis with mesangial and capillary wall deposition of immunoglobulin M (IgM), IgG, and C3. Electron microscopy showed immune-type electron-dense deposits in the mesangium and segmental subendothelial (2 cases) or subepithelial (1 case) deposits. Patients were treated with antibiotics, including azithromycin or doxycycline and ceftriaxone or tobramycin. In addition, 2 patients were administered steroids and 2 patients underwent valve replacement surgery. The 2 patients who underwent cardiac surgery were discharged from the hospital with stable renal function. The third patient died 4 months after hospital admission of renal failure. In conclusion, glomerulonephritis caused by B henselae endocarditis is an immune complex-mediated disease characterized by segmental necrotizing and crescentic glomerular lesions that can respond to aggressive medical and surgical therapy.
authors.affiliation: Department of Medicine, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Ian
authors.initials: I
authors.lastname: Bookman
authors.forename: James W
authors.initials: JW
authors.lastname: Scholey
authors.forename: Sarbjit V
authors.initials: SV
authors.lastname: Jassal
authors.forename: Ginette
authors.initials: G
authors.lastname: Lajoie
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Herzenberg
mesh_terms: D000328:Adult; D001474:Bartonella Infections / Q000150:complications* / Q000175:diagnosis; D018416:Bartonella henselae / Q000276:immunology; D001706:Biopsy; D004697:Endocarditis, Bacterial / Q000150:complications*; D005260:Female; D005921:Glomerulonephritis / Q000209:etiology* / Q000276:immunology / Q000473:pathology; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D008875:Middle Aged; D009336:Necrosis