Abstract: FR-PO1085
Comparison of Two Renal Staging Systems and Response Criteria of AL Amyloidosis
Session Information
- Glomerular Diseases: Clinical, Outcomes, Trials - II
October 26, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1203 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Drosou, Maria Eleni, Mayo Clinic , Rochester, Minnesota, United States
- Muchtar, Eli, Mayo Clinic , Rochester, Minnesota, United States
- Leung, Nelson, Mayo Clinic , Rochester, Minnesota, United States
Background
Light chain (AL) amyloidosis affects the kidney in 70% of the patients. Renal survival and response are critical for the treatment decision. We carried out this study to evaluate the two sets of baseline staging system and renal response and progression criteria (Palladini et al. and Kastritis et al.) recently proposed in our own population.
Methods
AL cases with renal involvement at Mayo Clinic between 01/2003 and 01/2015 were screened. Patients were excluded if: dialysis dependence at the time of diagnosis or <3 months of treatment initiation, incomplete data set and treatment initiation more than 1 month before AL diagnosis. Our cohort was evaluated at baseline and at 3, 6 and 12 months. The study’s endpoint was renal survival, defined as the time from treatment initiation to dialysis initiation or of last follow up. We used competing risks statistical analysis and the C (Concordance) index to compare the two models.
Results
Out of 836 patients with AL and renal involvement, 495 were selected. The median age was 61(54-68) years and 62% were male. Median serum creatinine was 1.1(0.9-1.4) mg/dl, median eGFR was 66(47-82) ml/min/1.73 m2 and median proteinuria was 5.1(2.5-8.2) g/d. Table 1 shows the distribution of our cohort in stages. For ESRD onset, hazard ratio (HR) for stage II vs I was 21[NL1] (p= 0.003) and for stage III vs II was 3.02(p<0.001) for the Palladini staging system (C= 0.74). HR for stage II vs I was 4.3 (p=0.161) and for stage III vs II was 4.76 (p< 0.001) for the Kastritis staging (C =0.73). At 3 months, neither criteria met statistically significant predictive value. The Palladini progression criteria were superior both at 6 months [HR: 9.68 (p<0.001, C =0.79) vs HR: 3.03 (p=0.002, C= 0.65)] and at 12months [HR: 7.24 (p<0.001, C =0.75) vs HR: 5.47(p<0.001, C=0.72)]. Both response criteria showed comparable results at 6 and 12 months after treatment initiation.
Conclusion
Both Palladini and Kastritis renal staging systems predict renal survival well. Renal progression and response assessed using serum creatinine and 24 hour urine protein appear to have little prognostic value earlier than 6 months.
Distribution of Patients by Different Staging Systems
| Palladini Stage System | Kastritis Staging System | |
| Stage I | 171 (34.5%) | 89 (18%) |
| Stage II | 257 (52%) | 221 (45%) |
| Stage III | 67 (13.5%) | 185 (37%) |