Membranoproliferative glomerulonephritis in childhood: factors affecting prognosis

Prognostic factors in children with membranoproliferative glomerulonephritis type I

The clinical outcome of patients with membranoproliferative glomerulonephritis (MPGN) varies, with some patients progressing to end-stage renal disease. The aim of this retrospective study was to analyze the initial clinical signs and laboratory test results associated with an MPGN prognosis. The study cohort consisted of 47 patients with idiopathic MPGN Type I treated at the National Institute of Pediatrics, Mexico City, between 1971 and 2001. The median follow-up was 3 years. The three different outcomes of interest were death, renal failure, and nephrotic syndrome. The patients' ages ranged between 4 and 16 years. All patients had different degrees of proteinuria, hyperlipidemia, and microscopic/macroscopic hematuria, and 85.1% of them showed hypocomplementemia. Clinical outcomes varied, however, the most common was nephrotic syndrome, either alone or combined with other syndromes, which accounted for 74.5% of all cases. Fifteen patients died. Treatment with methylprednisolone improved the patient's condition, while the use of chloroquine or cyclophosphamide worsened it. Twenty-two patients had some degree of renal failure; glomerular filtration rate (GFR) levels and albumin values were negatively associated to renal failure, while treatment with methylprednisolone decreased the probability of renal failure. Nephrotic syndrome persisted in 18 patients; hemolytic complement and hemoglobin values were negatively associated with nephrotic syndrome, while macroscopic hematuria was positively associated with it. Signs that suggested a poor prognosis during diagnosis were low GFR, low albumin, low hemolytic complement, and macroscopic hematuria. Treatment with methylprednisolone seemed to improve prognosis, however, this needs to be confirmed with randomized studies.

Remission of membranoproliferative glomerulonephritis type I with the use of tacrolimus

Membranoproliferative glomerulonephritis, albeit uncommon, is associated with considerable morbidity and mortality in children. Corticosteroids are the mainstay of therapy for severe disease, although data supporting their use are limited. We report our experience in treating two children with nephrotic-nephritic syndrome from idiopathic membranoproliferative glomerulonephritis. Both children experienced a suboptimal response to prolonged courses of steroids and were started on tacrolimus as a steroid-sparing agent. Rapid and complete remission was achieved in both children after initiation of tacrolimus. The purpose of our report is to increase awareness of health care professionals to the potential benefits of this agent in inducing remission in children with severe membranoproliferative glomerulonephritis.

Management of membranoproliferative glomerulonephritis: evidence-based recommendations

Idiopathic membranoproliferative glomerulonephritis (MPGN) is one of the least common types of GN. This article critically evaluates the literature and generates evidence-based recommendations for the management of idiopathic MPGN. For all age groups, for idiopathic MPGN with normal renal function and asymptomatic nonnephrotic range proteinuria, no specific therapy is necessary (grades B and C). Close follow-up every three to four months, with specific attention to renal function, proteinuria, and blood pressure control, is recommended. In children with MPGN and nephrotic syndrome and/or impaired renal function, a trial of steroids is warranted (grade A). The best data suggest high-dose, alternate-day steroids for a period of 6 to 12 months (40 mg/m2 on alternate days). If no benefit is seen, discontinuation with close follow-up and attention to conservative treatment (that is, blood pressure control, use of agents to reduce proteinuria, and correction of metabolic abnormalities) is recommended. In adults with MPGN, impaired renal function, and/or nephrotic-range proteinuria, a trial of aspirin (325 mg daily), dipyridamole (75 to 100 mg tid), or a combination of the two for 12 months is reasonable (grade B). Again, if no benefits are seen, the treatment should be stopped. Attention to factors known to delay the progression of renal decline and close follow-up should be part of the treatment plan (grades B and C).

Glomerulonephritis

The differential diagnosis of glomerulonephritis without systemic disease includes poststreptococcal glomerulonephritis, IgA nephropathy, rapidly progressive glomerulonephritis (RPGN), and membranoproliferative glomerulonephritis (MPGN). Glomerular inflammation is probably induced directly by a nephritogenic streptococcal protein in poststreptococcal glomerulonephritis, and by mesangial deposition of abnormally glycosylated IgA1-containing immune aggregates in IgA nephropathy. In crescentic RPGN the role of cellular rather than humoral immune mechanisms is now becoming clear. Many patients with MPGN have chronic hepatitis C infection. There is no effective disease-specific therapy for poststreptococcal glomerulonephritis or IgA nephropathy. RPGN benefits from high-dose steroids and cytotoxic drug therapy with the addition of plasma exchange in disease induced by antibody to glomerular basement membrane. Antiviral therapies reduce the severity of MPGN due to hepatitis C virus. However, various new therapies directed at specific cytokines, growth factors, fibrin deposition, and other mediators of injury are being developed, as well as more specific and less toxic forms of immunotherapy.