Clinical Analysis Of Iga Nephropathy In Patients Over 50 Years Of Age / 대한내과학회지

ABSTRACT

BACKGROUND: IgA nephropathy is recognized as a disease affecting primarily young men under 30 years of age but it is relatively uncommon over 50 years of age. Findings on clinical and histological presentation and outcome of over 50 years of age have rarely published in Korea. METHODS: Between Febrary 1994 and July 2003, one hundred and thirty nine IgAN patients were recruited over 8 years. Nineteen patients over age 50 were compared to one hundred and twenty patients under age 50 clinical, histological findings, 5-Yr renal survival rate. Mean post-biopsy follow-up month was 23.8 +/- 23.5 months. RESULTS: Both group of patients were similar to baseline for gross hematuria, Male and female ratio. But older patients had a higher incidence of daily for 24 hour urine protein (p=0.010), systolic and diastolic blood pressure (p=0.010, p<0.01), serum C3 (p=0.001) and serum C4 (p=0.003). Albumin (p=0.011), creatinine clearance (p<0.01) were significantly lower in the older patients at the time of renal biopsy. Histologic grade IV was more common in the older patients (p=0.001). Moderate to severe mesangial proliferation (p=0.001) and crescent formation (p=0.043), arteriolosclerosis (p=0.006) were more common in older patients. Mesangial small deposition of IgA (p=0.007) and glomerular peripheral deposition of IgG, IgA, C1q (p=0.024, p=0.014, p=0.009) were more common in older patients than in under 50 years of age. Mesangial small electron dense deposits were more common in older patients than in younger patients (p=0.031). CRF (Ccr < 60 mL/min) was confirmed 55.6% over age 50 and 27.4% under age 50 (p=0.017). Renal replacement therapy was done 15.8% over age 50 and 4.3% under age 50 (p=0.048). 5-Year renal survival curves showed that kidney survival rate was 44.4% over age 50 and 72.6% under age 50 (p=0.0248). CONCLUSION: Poor prognostic factors were more common over age 50 than under age 50. CRF and renal replacement therapy were more common over age 50. Analysis of renal survival curves shows that the probability of developing ESRF increase after age 50. But, prolonged prospective follow-up is necessary to confirm this trend.