Endocarditis-associated rapidly progressive glomerulonephritis mimicking vasculitis: a diagnostic and treatment challenge

Abstract

Background Infective endocarditis (IE)-associated rapidly progressive glomerulonephritis (RPGN) is rarely reported. Sporadic case reports have noted the diagnostic and therapeutic challenge in IE-associated glomerulonephritis because it may masquerade as idiopathic vasculitis. Methods Patients with clinical diagnosis of IE-related RPGN in a tertiary hospital in China between January 2004 and May 2021 were identified and retrospectively reviewed. Results Twenty-four patients with IE-associated RPGN were identified. All patients presented with fever and multiorgan system involvement on top of heart and kidneys, spleen (79%, 19/24), skin (63%, 15/24), lung (33%, 8/24) and nervous system (17%, 4/24). Six of the 24 patients (25%) were initially suspected to have ANCA-associated or IgA vasculitis. Forty-five percent of patients are seropositive for ANCA. Renal histology showed mesangial and/or endocapillary hypercellularity with extensive crescents in most patients. C3-dominant deposition was the predominant pattern on immunofluorescence and pauci-immune necrotising crescentic glomerulonephritis was observed in one case. All patients received antibiotics with or without surgery. Six patients received immunosuppressive therapy before antibiotics due to misdiagnosis and seven patients received immunosuppressive therapy after antibiotics due to persistence of renal failure. Three of the 24 patients died due to severe infection. All the surviving patients had partial or complete recovery of renal function. Conclusion IE-associated RPGN is rare and the differential diagnosis from idiopathic vasculitis can be challenging due to overlaps in clinical manifestations, ANCA positivity and absence of typical presentations of IE. The prognosis is generally good if antibiotics and surgery are not delayed. The decision on introducing immunoruppressive treatment should be made carefully on a case by case basis when kidney function does not improve appropriately after proper anti-infective therapy. Key messages Infective endocarditis associated RPGN is rare and differentiating it from idiopathic vasculitis can be challenging due to overlap in clinical manifestations, ANCA positivity and occasional absence of typical manifestations of infective endocarditis. Kidney function usually responds to antibiotic therapy alone. Immunosuppressive therapy may be beneficial in carefully selected patients whose kidney function does not improve with antibiotics alone.

Proteinase‑3‑antineutrophil cytoplasmic antibody‑associated vasculitis secondary to subacute infective endocarditis: A case report

“…The differential diagnosis of secondary AAV from primary AAV can be challenging, especially for subacute infective endocarditis in which ~25% of the patients with RPGN are initially considered to have primary vasculitis (12). However, distinguishing AAV secondary to infection is highly valuable because of the entirely different therapies and outcomes used (12)(13)(14).…”

“…The differential diagnosis of secondary AAV from primary AAV can be challenging, especially for subacute infective endocarditis in which ~25% of the patients with RPGN are initially considered to have primary vasculitis (12). However, distinguishing AAV secondary to infection is highly valuable because of the entirely different therapies and outcomes used (12)(13)(14). In the present study, the patient was first diagnosed with primary PR3-AAV according to the 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides (1), based on crescent formation in the glomeruli, PR3-ANCA in the circulation and negative results from echocardiography and other screenings for malignancies or drugs.…”

Vaskulitis mimics

“…Sie sind einer der wichtigsten Auslöser der im Abschnitt Großgefäßvaskulitiden diskutierten infektiösen Aortitis. Neben der initial oft unspezifischen Manifestation als entzündliche Erkrankung mit Fieber, kommt es in zahlreichen Fällen zu immunologischen Begleitphänomenen, die leicht mit einer Vaskulitis verwechselt werden können [61,62]. Einerseits bestehen bei Endokarditiden häufig positive ANCA (ca.…”

“…16 %), Antiphospholipid-Antikörper (ca. 23 %) und eine Erniedrigung der Komplementfaktoren, andererseits kommt es zu (leukozytoklastischer) Vaskulitis der Haut, (Immunkomplex-)Nephritiden (teils mit Halbmondbildung und raschem Nierenversagen) oder Imitation entzündlicher Rundherde oder dem Bild intraparenchymaler Vaskulitismanifestationen durch septische Embolien oder intraparenchymale Blutungen [60,61,63]. Es besteht damit eine das Potenzial für die Verwechslung mit zahlreichen Vaskulitiden, darunter Großgefäßvaskulitiden, ANCA-assoziierten Vaskulitiden und Immunkomplexvaskulitiden.…”

Native and prosthetic valve infective endocarditis complicated by rapidly progressive glomerulonephritis and its diagnostic challenges and therapeutic implications

“…In a study of 595 IE‐related RPGN, the prevalence of IE‐related RPGN was found to be 3.4%. 2 These studies have also found that it was difficult to differentiate these cases from other differentials, like vasculitis. In a retrospective review of 24 cases of IE associated with RPGN, all patients presented with fever and multisystem organ involvement.…”