Abstract: FR-PO915
Long-Term Risk of ESKD in Postinfectious Glomerulonephritis
Session Information
- Glomerular Diseases: Potpourri
October 25, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Bjoerneklett, Rune, Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Bostad, Lars Sigurd, Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Knoop, Thomas, Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Bostad, Leif Henry, Department of Clinical Medicine, University of Bergen, Bergen, Norway
Background
Kidney biopsy is usually not required for the diagnosis of post-infectious
glomerulonephritis (PIN). When kidney biopsies are nevertheless performed for
example in patients with PIN and severe or atypical clinical presentations, the light
microscopic picture is characteristic in the form of endocapillary glomerulonephritis.
The immunological picture is however less specific for PIN as in many cases this is
dominated by complement factor C3 deposits. In such cases, PIN can theoretically be
confused with complement 3 nephropathy (C3N) based on the immunological findings.
While PIN is considered a self-limiting condition with a good prognosis, C3N, often has
a progressive course leading to end-stage kidney disease (ESKD) in a significant
proportion of patients. To what extent confusion of PIN versus C3N has occurred in
clinical practice in Norway is unknown. As such prognostic data is limited we have
analyzed the very long-term risk of ESKD in patients with biopsy-verified PIN registered
in the Norwegian Kidney Biopsy Registry (NKBR) in the period 1991-2012.
Methods
Cases of biopsy-verified PIN 1991-2012 including demographic, clinical, laboratory,
and histological variables at the time of diagnosis were retrieved from the NNBR. The
cohort was linked with the Norwegian Kidney Registry for identification of patients with
ESKD by May 1, 2024.
Results
We identified 82 patients with PIN. Men; 45 (55%), age; 35 years (SD 22), systolic BP;
140 mmHg (SD 24), diastolic BP; 80 (SD 14), hypertension 42 (51%), eGFR 58
ml/min/1.73m2 (SD 37), eGFR<15; 12 (15%), eGFR 15-29; 8 (10%) and eGFR 30-59; 26
(32%), serum albumin; 31 gram/liter (SD 6), proteinuria; 3.8 gram/24 hours (SD 4.2),
nephrotic syndrome; 20 (24%), crescents; 26 (32%), >50% tubulointerstitial fibrosis; 17
(21%) and isolated C3 positivity 29 (35%).
During an average observation time of 21 years, there were no patients who progressed
to ESKD.
Conclusion
Despite many cases with severe kidney affection at the time of diagnosis, no patients
with PIN progressed to ESKD during a very long follow-up time. A C3N resembling
immunological image is not associated with the risk of ESKD in patients with PIN.
Funding
- Commercial Support – Novartis