Renal involvement in eosinophilic granulomatosis with polyangiitis (EGPA): a multicentric retrospective study of 63 biopsy-proven cases

Abstract

Objective Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic small-vessel vasculitis characterized by asthma, hypereosinophilia and ANCA positivity in 40% of patients. Renal involvement is rare and poorly described, leading to this renal biopsy-proven based study in a large EGPA cohort. Methods We conducted a retrospective multicentre study including patients fulfilling the 1990 ACR criteria and/or the 2012 revised Chapel Hill Consensus Conference criteria for EGPA and/or the modified criteria of the MIRRA trial, with biopsy-proven nephropathy. Results Sixty-three patients [27 women, median age 60 years (18–83)] were included. Renal disease was present at vasculitis diagnosis in 54 patients (86%). ANCA were positive in 53 cases (84%) with anti-MPO specificity in 44 (83%). All patients had late-onset asthma. Peripheral neuropathy was present in 29 cases (46%), alveolar haemorrhage in 10 (16%). The most common renal presentation was acute renal failure (75%). Renal biopsy revealed pauci-immune necrotizing GN in 49 cases (78%). Membranous nephropathy (10%) and membranoproliferative GN (3%) were mostly observed in ANCA-negative patients. Pure acute interstitial nephritis was found in six cases (10%); important interstitial inflammation was observed in 28 (44%). All patients received steroids with adjunctive immunosuppression in 54 cases (86%). After a median follow-up of 51 months (1–296), 58 patients (92%) were alive, nine (14%) were on chronic dialysis and two (3%) had undergone kidney transplantation. Conclusion Necrotizing pauci-immune GN is the most common renal presentation in ANCA-positive EGPA. ANCA-negative patients had frequent atypical renal presentation with other glomerulopathies such as membranous nephropathy. An important eosinophilic interstitial infiltration was observed in almost 50% of cases.

Renal Involvement in Eosinophilic Granulomatosis With Polyangiitis

“…However, intrinsic renal injury is in fact not uncommon, and has been recorded in up to 25% of patients affected by EGPA. 1,4 As epitomized by the patient's history, EGPA typically follows three sequential stages. First, a prodromal phase characterized by atopic disease, allergic rhinitis and asthma, followed by a second eosinophilic phase defined by peripheral blood eosinophilia and eosinophilic infiltration of multiple organs and, lastly, a vasculitic stage marked by life-threatening systemic vasculitis affecting medium and small vessels.…”

“…2 Renal disease in EGPA is closely associated with ANCA positivity. 1,2,4 Indeed, patients with positive ANCA account for 80% of EGPA patients with renal involvement, although they represent less than 40% of all patients in most EGPA series. 1,4 Necrotizing pauci-immune glomerulonephritis is the most common renal presentation, found in 88% of ANCA-positive EGPA cases with renal involvement.…”

“…1,2,4 Indeed, patients with positive ANCA account for 80% of EGPA patients with renal involvement, although they represent less than 40% of all patients in most EGPA series. 1,4 Necrotizing pauci-immune glomerulonephritis is the most common renal presentation, found in 88% of ANCA-positive EGPA cases with renal involvement. 4 Compared to MPA and GPA vasculitis, where kidney disease is frequently diagnosed at advanced stages, most EGPA patients with rapidly J o u r n a l P r e -p r o o f progressive glomerulonephritis exhibit crescentic lesions, reflecting recent and acute insult.…”

“…1,4 Necrotizing pauci-immune glomerulonephritis is the most common renal presentation, found in 88% of ANCA-positive EGPA cases with renal involvement. 4 Compared to MPA and GPA vasculitis, where kidney disease is frequently diagnosed at advanced stages, most EGPA patients with rapidly J o u r n a l P r e -p r o o f progressive glomerulonephritis exhibit crescentic lesions, reflecting recent and acute insult. This pattern of renal injury may translate to an early recognition of renal disease heralded by demonstrative EGPA-associated extra-renal symptoms.…”

Renal Involvement as Rare Acute Tubulointerstitial Nephritis in a Patient with Eosinophilic Disorder Treated with Early Add-on Administration of Mepolizumab

“…Recently, a multicentric retrospective study by the GERM"O"P and the European Respiratory Society Taskforce on EGPA reported no TIN in 157 EGPA patients based on the presence or absence of definitive vasculitis features and/or ANCA status (13). A more recent multicentric retrospective study of 63 biopsy-proven cases with EGPA (53 ANCA-positive cases and 10 ANCA-negative cases) revealed that isolated TIN was found in 5 (9%) ANCA-positive cases and 1 (10%) ANCA-negative case, suggesting that isolated TIN can occur in both ANCA-positive and ANCA-negative EGPA patients (14).…”