Clinical Characteristics and Prognostic Factors in Systemic Amyloidosis: A Single-Center Experience

Abstract

Background: Systemic amyloidosis encompasses a spectrum of protein misfolding disorders that result in amyloid deposition and organ dysfunction. Amyloid A (AA) amyloidosis, typically secondary to chronic inflammatory diseases, remains an important cause of renal morbidity. Methods: This retrospective single-center cohort study included 79 patients with biopsy-proven systemic amyloidosis diagnosed between 2010 and 2016. Demographic, clinical, and laboratory data were analyzed to identify factors associated with renal replacement therapy (RRT) and overall survival. Amyloid subtypes were determined by histopathology and immunohistochemistry. Results: Of the 79 patients, 62 (78.5%) had AA amyloidosis and 17 (21.5%) other types. The mean age was 55.8 ± 15.8 years, and 53.2% were female. The kidneys were the most frequently involved organ (75.6%), and nephrotic syndrome was present in 50%. RRT was required in 33.8%, and overall mortality was 43%. Patients with AA amyloidosis were younger (p=0.047) and had higher creatinine and inflammatory markers (p<0.05). In multivariate Cox analysis, baseline serum creatinine (HR=1.20, 95% CI 1.11–1.30, p<0.001) and proteinuria (HR=1.10, 95% CI 1.01–1.20, p=0.031) were independently associated with RRT requirement. Older age was associated with mortality (HR=1.05, 95% CI 1.01–1.09, p=0.006). Conclusion: In systemic amyloidosis, renal involvement is common and strongly influences outcomes. Baseline renal function and proteinuria are key predictors of progression to RRT, while age remains the main determinant of overall survival.

Keywords

• amyloidosis
• mortality
• prognosis
• kidney disease

Clinical Characteristics and Prognostic Factors in Systemic Amyloidosis: A Single-Center Experience

Abstract

References

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