Kidney Week

Abstract: SA-PO647

ANCA-Associated Glomerulonephritis Without Crescent Formation Has Atypical Clinicopathological Features: A Multicenter Retrospective Study

Session Information

• Glomerular Diseases: ANCA, Anti-GBM, Kidney Biopsy
  November 09, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1203 Glomerular Diseases: Clinical, Outcomes, and Trials

Authors

• Suzuki, Kazuyuki, Kanazawa University, Kanazawa, Japan

Kazuyuki Suzuki,

• Zoshima, Takeshi, Kanazawa University Hospital, Kanazawa, Japan

Takeshi Zoshima,

• Suzuki, Fae, Kanazawa University Graduate School of Medicine, Kanazawa, Japan

Fae Suzuki,

• Hara, Satoshi, Kanazawa University Graduate School of Medicine, Kanazawa, Japan

Satoshi Hara,

• Kawano, Mitsuhiro, Kanazawa University Hospital, Kanazawa, Japan

Mitsuhiro Kawano,

Background

The most typical histopathological feature of ANCA-associated glomerulonephritis (ANCA-GN) is crescentic GN. However, ANCA-GN sometimes includes tubulointerstitial or vascular-dominant inflammation without crescent (C) formation. Few reports have focused on ANCA-GN without C in a large multicenter study. We aimed to identify the clinicopathological features of ANCA-GN without C.

Methods

We enrolled 147 Japanese ANCA-GN patients who were subjected to renal biopsy in 17 hospitals from 2001 to 2018. We measured various clinical parameters at the time of renal biopsy, and determined the presence of comorbidities. We also measured serum Cr and eGFR at the last patient visit, and recorded medications prescribed for ANCA-GN. We retrospectively compared these clinical and histological findings between those with C (C+ group) and without C (C- group). The endpoint was the cumulative percentage of patients who died from any cause.

Results

Of 147 patients (76 females; mean age 69.2 years; observational period 39.5 months), 25 (17.1%) were in C- group. Although C- group had less proteinuria (0.7±0.8 vs 1.7±1.6 g/gCr, p<0.01) and hematuria (75.0% vs 99.1%, p<0.01) with better renal function (eGFR; 53.9±28.7 vs 32.2±24.6 ml/min/1.73m², p<0.01), they had higher CRP levels (10.9±7.9 vs 6.6±6.1 mg/dl, p<0.01) than C+ group. There were no significant differences in any other clinical findings including ANCA serology. In histological findings, C- group had a higher frequency of arteritis (41.7% vs 17.5%, p=0.01), while other histological findings such as arteriolitis and tubulointerstitial lesions did not differ. Corticosteroid was less often prescribed in C- group (84.0% vs 100%, p<0.01). There was no significant difference in observational period, and C- group had better latest renal function (eGFR; 53.9±32.1 vs 40.6±29.4 ml/min/1.73m², p=0.05) than C+ group. However, overall survival rate did not differ (76.0% vs 79.6%, p=0.78).

Conclusion

ANCA-GN without C had specific clinicopathological features including higher systemic inflammation and frequency of renal arteritis than ANCA-GN with C. Though renal function throughout the clinical course was better in ANCA-GN without C, overall survival rate was similar with ANCA-GN with C.