Abstract: TH-PO661
Role of Repeat Kidney Biopsy in Lupus Nephritis in a Uruguayan Cohort
Session Information
- Lupus Nephritis: Clinical, Outcomes, and Therapeutics
October 24, 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
- Parnizari, Paula, Hospital de Clinicas Doctor Manuel Quintela, Montevideo, Montevideo, Uruguay
- Boggia, Jose, Hospital de Clinicas Doctor Manuel Quintela, Montevideo, Montevideo, Uruguay
- Luzardo, Leonella, Hospital de Clinicas Doctor Manuel Quintela, Montevideo, Montevideo, Uruguay
- Ottati, Gabriela, Hospital de Clinicas Doctor Manuel Quintela, Montevideo, Montevideo, Uruguay
- Noboa, Oscar A., Hospital de Clinicas Doctor Manuel Quintela, Montevideo, Montevideo, Uruguay
Background
There is no biomarker that substitutes renal biopsy in assessment of histopathological class, activity, or chronicity in lupus nephritis (LN). We aim to characterize clinical and histological features of repeat biopsies by clinical indication in LN.
Methods
We reviewed the clinical charts and pathology reports of patients with LN and two renal biopsies from a University Hospital in Uruguay.
Results
A total of 20 patients, 18 women were analyzed. Clinical characteristics are shown in Table 1. In 5/9 patients biopsied because of mild clinical changes (hematuria and/or sub-nephrotic proteinuria), pathology revealed severe proliferative forms. Repeat biopsy showed a change in LN class in 80% of the sample, 18.2% to a lower class, 35% to a higher class and 30% had an additional membranous pattern (Class IV+V). There was also an increase in interstitial fibrosis and tubular atrophy (IFTA), 5 vs 20% (p 0.019) and the presence of moderate-severe IFTA was associated with lower eGFR after initial treatment (p 0.009). After repeat biopsy immunosuppression was intensified in 17 patients (85%).
Conclusion
Change in LN class was frequent in this cohort and there was a significant increase in chronic changes in repeat biopsies with a negative impact in renal function. Repeat biopsy by clinical indication is a valuable tool in LN management.
Baseline characteristics according to first and second biopsy
| First biopsy | Second biopsy | p value | |
| Age at time of the biopsy (y), mean (SD) | 26.2±11.5 | 33.1±11.7 | <0.0001 |
| Microscopic hematuria and/or proteinuria, n(%) | 5 (25) | 4 (20) | 0.705 |
| Nephrotic syndrome, n (%) | 10 (50) | 12 (60) | 0.525 |
| Nephritic syndrome, n (%) | 1 (5) | 0 | --- |
| RPGN, n (%) | 3 (15) | 3 (15) | --- |
| LN Class I/II, n (%) | 3 (15) | 3 (15) | --- |
| LN Class III, n (%) | 4 (20) | 1 (5) | --- |
| LN Class IV, n (%) | 11 (55) | 8 (40) | --- |
| LN Class V, n (%) | 2 (10) | 2 (10) | --- |
| LN Class III/IV+V, n (%) | 0 | 6 (30) | --- |
| Creatinine (mg/dl), median (IQR) | 1.08 (0.70-1.45) | 1.00 (0.70-1.40) | 0.730 |
| eGFR (ml/min/1.73m2), median (IQR) | 72.7 (51.7-111.8) | 73.7 (46.6-118.5) | 0.988 |
| Proteinuria (g/24hs), median (IQR) | 3.94 (2.35-6.40) | 4.29 (2.56-6.25) | 0.883 |
| Initial treatment | |||
| Corticosteroids | 20 (100) | 19 (100) | --- |
| Cyclophosphamide | 11 (55) | 10 (52.6) | --- |
| Mycophenolate | 2 (10.1) | 10 (52.6) | 0.001 |
| Azathioprine | 6 (30) | 1 (5) | 0.001 |