Prevalence of renal involvement in Indian patients with systemic sclerosis

Background: Renal involvement in systemic sclerosis (SSc) either in the form of scleroderma renal crisis (SRC) or nonrenal crisis abnormalities has been reported to be in the range of 60-80%. Renal involvement is thought to be rare in Indian patients with SSc. However, there is paucity of data.
Aims: To study the frequency and pattern of renal involvement in Indian patients with SSc.
Settings and Design: A single center prospective, cross sectional study.
Materials and Methods: We prospectively evaluated the patients with SSc attending the Rheumatology Clinic. All patients were evaluated for renal involvement. All patients underwent measurement of blood pressure, urine examination, glomerular filtration rate (GFR) estimation using Cockcroft-Gault formula and kidney biopsy when indicated.
Statistical Analysis: Statistical analysis was performed using SAS 8.0 statistical package.
Results: Eighty-seven patients were included in the study from July 2001 to December 2004. Mean age of patients was 36.88 ± 12.51 years. About 30% of patients had diffuse cutaneous SSc. None of these patients had SRC either at enrollment in the study or during follow-up. Eleven (12.6%) patients had hypertension. Six (6.9%) patients had abnormal urinary findings in the form of either active urinary sediment or significant proteinuria. Only one patient had azotemia (plasma creatinine > 1.8 mg/dl). Calculated GFR < 90 ml/min was seen in about 75% patients, out of these about 30% patients had chronic kidney disease.
Conclusion: SRC is very rare in Indian patients with SSc. However, non-renal crisis abnormalities appear to be as common in Indian patients as compared to the western literature.