Treatment of IgA nephropathy with renal insufficiency

Abstract

IgA Nephropathy leads young people to dialysis more often than other glomerular diseases, because often diagnosis and therapy are made late. Nephrologists waive to treat IgAN pts with chronic renal insufficiency, believing that treatment may not be effective and safe. Moreover, studies in IgAN pts with reduced renal function are lacking. Small studies seem to indicate a possible utility of RAS blockers and corticosteroids in these patients. Recently, VALIGA study showed that corticosteroids and immunosuppressants were more frequently used in pts with eGFR <30 ml/min than in those with eGFR >30 ml/min (60 vs. 44 %, respectively; p = 0.004). The goal of treating IgAN pts is to obtain a time-average proteinuria <1 g/day, regardless of the degree of renal function and histological damage. RASB and corticosteroids seem to be able to obtain this result. However, it's important to pay attention to the appearance of adverse events of CS. In the literature, major side effects occurred in 29 of 463 (6.2 %) patients enrolled in RCTs. However, scarce informations are obtained about the safety of CS in patients with reduced renal function. To better evaluate this aspect, we considered three studies, that used similar schemes of therapy and included patients with different degrees of renal function (1: GFR 90 ml/min/1.73 m(2), 2: 81 ml/min/1.73 m(2), 3: 34 ml/min/1.73 m(2)). The occurrence of adverse events increased with the worsening of renal function (2.3, 5.7 and 15.4 % in studies 1, 2 and 3 respectively). The aim of the treatment for a patient with an eGFR <30 is to slow the progression and to delay the need for dialysis. Therefore, in stage CKD 2, 3 and 4 with a proteinuria >1 g/day a 6-month course of corticosteroids could be useful and safe.

Keywords: Chronic kidney disease; Corticosteroids; IgA nephropathy; Immunosuppressants; RAS blockers; Time-average proteinuria.