Efficacy of losartan in patients with primary focal segmental glomerulosclerosis resistant to immunosuppressive treatment

Abstract

Objectives. Angiotensin II may play an important role in the progression of renal disease. Currently, angiotensin converting enzyme (ACE) inhibitors and angiotensin II receptor antagonists are commonly used for renoprotection. To our knowledge, there is no study investigating this effect of angiotensin II receptor antagonists in patients with primary focal segmental glomerulosclerosis (FSGS) in the literature. The aim of this study was to evaluate the effects of losartan on proteinuria and renal function in patients with FSGS refractory to immunosuppressive treatment. Design. Twenty-three normotensive patients with FSGS proven through renal biopsy were included in the study. Thirteen of them, five men and eight women, were given losartan in a dose of 50 mg day(-1) during 12 months, and 10, four men and six women, were in the control group. Mean arterial blood pressure (MAP), 24-h urine protein excretion, serum total protein and albumin levels were determined just before the start of treatment as well as after 1, 6 and 12 months of the study. In addition, serum creatinine, creatinine clearence (CrCl), cholesterol and triglyceride levels were determined at the beginning and end of the study. Results. Age, gender and baseline levels of proteinuria, serum albumin, total protein, creatinine, CrCl and MAPs were similar in the two groups. Nephrotic range of proteinuria was present in five of 13 patients (38.4%) in the losartan group and in four of 10 patients (40%) in the control group. In the losartan group, 24-h proteinuria had decreased from 3.6 +/- 0.5 g to 2.3 +/- 0.5 g after 1 month, to 2.4 +/- 0.7 g after 6 months and to 1.9 +/- 0.7 g after 12 months. In the control group, a significant increase in proteinuria compared with the baseline value was noticed after 12 months. Proteinuria levels were significantly higher in the control group than in the losartan group after 6 and 12 months. Whilst total protein and albumin levels increased in the losartan group, they did not change significantly in the control group. The total protein levels after 6 and 12 months, and albumin levels after 6 months were significantly higher in the losartan group than in the control group. No significant change was observed between the baseline and the 12-month creatinine and CrCl levels of the groups when intra- and inter-group comparisons were made. Furthermore, serum cholesterol levels of the losartan group were reduced significantly. The changes in MAP values did not reach significant levels in either of the groups. There was no correlation between the percentage changes in MAP and in proteinuria of the losartan group after 12 months. Conclusions. Angiotensin II receptor antagonists may be an alternative therapy in FSGS patients who are resistant to immunosuppressive therapy.