Differences in new-onset IgA nephropathy between young adults and the elderly.

BACKGROUND

The goal of this study was to define the clinical and histological differences in new-onset IgA nephropathy between young adults and the elderly.

METHODS

We retrospectively examined renal biopsy findings, clinical features at presentation and outcomes in 82 young adults (mean age 30.3+/-10.2 years) and 17 elderly patients (mean age 71.9+/-4.5 years) with IgA nephropathy whose renal biopsies were taken within 1 year from the onset of renal manifestations.

RESULTS

The elderly group more frequently had hypertension (p<0.001), acute renal failure (p<0.001), and nephrotic range proteinuria (p=0.001) at presentation than the young adults group. On histology, a higher percentage of globally sclerotic glomeruli (p<0.001) was present in the elderly group. In patients presenting with acute renal failure, the elderly group more frequently had an intercurrent disease (p=0.02), mostly infection, and a higher mortality rate (p=0.033). On histology, the young adults group had a higher percentage of glomeruli affected by crescents (p=0.027); in contrast, the elderly group more commonly had acute tubular injury (p=0.02).

CONCLUSIONS

The elderly patients affected by IgA nephropathy had more severe renal manifestations at presentation (acute renal failure in 52.9% and nephrotic syndrome in 41.2% of patients). In cases of acute renal failure, the elderly patients had more predominant tubular rather than glomerular injury. Moreover, the considerable mortality rate (44.4%) might be associated with the intercurrent disease, mostly infection, which was more commonly present in the elderly patients.