Pankaj Hari

Clinical Features of Anti-Factor H Autoantibody–Associated Hemolytic Uremic Syndrome

Atypical hemolytic uremic syndrome (aHUS) is a rare form of thrombotic microangiopathy that associates, in 70% of cases, with genetic or acquired disorders leading to dysregulation of the alternative pathway of complement. Autoantibody directed against Factor H causes at least 6% to 10% of aHUS cases, but only a few clinical reports are available. Here, we describe the clinical, biologic, genetic features, treatment, and outcome of 45 patients who presented with aHUS associated with anti-FH autoantibody. We found that this form of aHUS primarily affects children between 9 and 13 years old but it also affects adults. It presents with a high frequency of gastrointestinal symptoms and with extrarenal complications and has a relapsing course. Activation of the alternative pathway of complement at the onset of disease portends a poor prognosis. Early specific treatment may lead to favorable outcomes. These data should improve the recognition and diagnosis of this form of aHUS and help identify patients at high risk of a poor outcome.

Efficacy and Safety of Treatment with Rituximab for Difficult Steroid-Resistant and -Dependent Nephrotic Syndrome: Multicentric Report

BACKGROUND AND OBJECTIVES The treatment of idiopathic nephrotic syndrome is often complicated by a refractory and relapsing course, with risk of drug toxicity and progressive renal failure. We report the efficacy and safety of rituximab in patients with steroid-resistant (SRNS) and steroid-dependent nephrotic syndrome (SDNS) refractory to standard therapy. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS This was a cohort study in academic, tertiary care centers in India and the United States. Patients with SRNS or SDNS, not responding to medications or showing calcineurin inhibitor toxicity, treated with two to four doses of intravenous rituximab, and followed ≥12 months were included. Remission was termed as complete, partial, or no response. RESULTS Thirty-three patients with SRNS (24 initial, 9 late resistance) and 24 with SDNS, with mean ages of 12.7 ± 9.1 and 11.7 ± 2.9 years, respectively, were included. Six months after rituximab therapy, 9 (27.2%) patients with SRNS showed complete remission, 7 (21.2%) had partial remission, and 17 (51.5%) had no response. At 21.5 ± 11.5 months, remission was sustained in 15 (complete: 7, partial: 8) patients. Of 24 patients with SDNS, remission was sustained in 20 (83.3%) at 12 months and in 17 (71%) at follow-up of 16.8 ± 5.9 months. The mean difference in relapses before and 12 months after treatment with rituximab was 3.9 episodes/patient per year. CONCLUSIONS Therapy with rituximab was safe and effective in inducing and maintaining remission in a significant proportion of patients with difficult SRNS and SDNS.

Prompt plasma exchanges and immunosuppressive treatment improves the outcomes of anti-factor H autoantibody-associated hemolytic uremic syndrome in children

Antibodies to complement factor H are an uncommon cause of hemolytic uremic syndrome (HUS). Information on clinical features and outcomes in children is limited. In order to explore this we studied a multicenter cohort of 138 Indian children with anti-complement factor H antibody associated HUS, constituting 56% of patients with HUS. Antibody titers were high (mean 7054 AU/ml) and correlated inversely with levels of complement C3, but not complement factor H. Homozygous deletion of the CFHR1 gene was found in 60 of 68 patients. Therapies included dialysis in 119 children, 105 receiving plasma exchanges and 26 intravenous immunoglobulin. Induction immunosuppression consisted of 87 children receiving prednisolone with or without intravenous cyclophosphamide or rituximab. Antibody titers fell significantly following plasma exchanges and increased during relapses. Adverse outcome (stage 4-5 CKD or death) was seen in 36 at 3 months and 41 by last follow up, with relapse in 14 of 122 available children. Significant independent risk factors for adverse outcome were an antibody titer over 8000 AU/ml, low C3 and delay in plasma exchange. Combined plasma exchanges and induction immunosuppression resulted in significantly improved renal survival: one adverse outcome prevented for every 2.6 patients treated. Maintenance immunosuppressive therapy, of prednisolone with either mycophenolate mofetil or azathioprine, significantly reduced the risk of relapses. Thus, prompt use of immunosuppressive agents and plasma exchanges are useful for improving outcomes in pediatric patients with anti-complement factor H-associated HUS.

Efficacy and Safety of Tacrolimus Versus Cyclosporine in Children With Steroid-Resistant Nephrotic Syndrome: A Randomized Controlled Trial

BACKGROUND To examine whether tacrolimus is more effective and safe than cyclosporine (CsA) in inducing remission in patients with steroid-resistant nephrotic syndrome (SRNS). STUDY DESIGN Randomized controlled trial, nonblind, parallel group. SETTINGS & PARTICIPANTS Tertiary-care hospital; 41 consecutive patients with idiopathic SRNS, estimated glomerular filtration rate greater than 60 mL/min/1.73 m(2), and histological characteristics showing minimal change disease, focal segmental glomerulosclerosis, or mesangioproliferative glomerulonephritis were randomly assigned to treatment with tacrolimus (n = 21) or CsA (n = 20). INTERVENTION Tacrolimus (0.1 to 0.2 mg/kg/d) or CsA (5 to 6 mg/kg/d) for 1 year; cotreatment with alternate-day prednisolone and enalapril. OUTCOMES Patients achieving complete remission (urinary protein-creatinine ratio < 0.2 g/g and serum albumin > or = 2.5 g/dL) or partial remission (urinary protein-creatinine ratio, 0.2 to 2 g/g, and serum albumin > or =2.5 g/dL) at 6 and 12 months; time to remission; proportion with relapses; side effects. RESULTS No patient was lost to follow-up. After 6 months of therapy, remission occurred in 18 (85.7%) and 16 patients (80%) treated with tacrolimus and CsA, respectively (relative risk [RR], 1.07; 95% confidence interval [CI], 0.81 to 1.41). Rates of remission at 12 months were also similar (RR, 1.14; 95% CI, 0.84 to 1.55). The proportion of patients who experienced relapse was significantly greater in those receiving CsA compared with tacrolimus (RR, 4.5; 95% CI, 1.1 to 18.2; P = 0.01). The decrease in blood cholesterol levels was greater with tacrolimus compared with CsA (difference in mean values, 45.1 mg/dL; 95% CI, 19.1 to 71.2). Persistent nephrotoxicity necessitating stoppage of medicine was seen in 4.7% and 10% patients, respectively. Cosmetic side effects (hypertrichosis and gum hypertrophy) were significantly more frequent in CsA-treated patients (P < 0.001). LIMITATIONS Single-center study, small sample size, and short duration of follow-up. CONCLUSIONS Tacrolimus or CsA in combination with low-dose steroids show similar efficacy in inducing remission in patients with SRNS. Therapy with tacrolimus is a promising alternative to CsA in view of the lower risk of relapses and lack of cosmetic side effects.

Serum-soluble urokinase receptor levels do not distinguish focal segmental glomerulosclerosis from other causes of nephrotic syndrome in children.

In this prospective study, we measured serum levels of the soluble urokinase receptor (suPAR) in pediatric patients with nephrotic syndrome of various etiologies. Mean levels of suPAR were 3316 pg/ml in 99 patients with steroid-resistant focal segmental glomerulosclerosis and 3253 pg/ml in 117 patients with biopsy-proven minimal change disease, which were similar to that of 138 patients with steroid-sensitive nephrotic syndrome (3150 pg/ml) and 83 healthy controls (3021 pg/ml). Similar proportions of patients in each group had suPAR over 3000 pg/ml. Compared with controls, suPAR levels were significantly higher in patients with focal segmental glomerulosclerosis (FSGS) and estimated glomerular filtration rate (eGFR) under 30 ml/min per 1.73 m(2) (6365 pg/ml), congenital nephrotic syndrome (4398 pg/ml), and other proteinuric diseases with or without eGFR under 30 ml/min per 1.73 m(2) (5052 and 3875 pg/ml, respectively; both significant). There were no changes following therapy and during remission. Levels of suPAR significantly correlated in an inverse manner with eGFR (r=-0.36) and directly with C-reactive protein (r=0.20). The urinary suPAR-to-creatinine ratio significantly correlated with proteinuria (r=0.25) in 151 patients and controls. Using generalized estimating equations approach, serum suPAR significantly correlated with eGFR (coefficient=-13.75), age at sampling (2.72), and C-reactive protein (39.85). Thus, serum suPAR levels in nephrotic syndrome are similar to controls, and do not discriminate between FSGS, minimal change disease, or steroid-responsive illness.

The bone and mineral disorder of children undergoing chronic peritoneal dialysis

The mineral and bone disorder of chronic kidney disease remains a challenging complication in pediatric end-stage renal disease. Here, we assessed symptoms, risk factors and management of this disorder in 890 children and adolescents from 24 countries reported to the International Pediatric Peritoneal Dialysis Network Registry. Signs of this disease were most common in North American patients. The prevalence of hyperphosphatemia increased with age from 6% in young infants to 81% in adolescents. Serum parathyroid hormone (PTH) was outside the guideline targets in the majority of patients and associated with low calcium, high phosphorus, acidosis, dialysis vintage and female gender. Serum calcium was associated with dialytic calcium exposure, serum phosphorus with low residual renal function and pubertal status. PTH levels were highest in Latin America and lowest in Europe. Vitamin D and its active analogs were most frequently administered in Europe; calcium-free phosphate binders and cinacalcet in North America. Clinical and radiological symptoms markedly increased when PTH exceeded 300 pg/ml, the risk of hypercalcemia increased with levels below 100 pg/ml, and time-averaged PTH concentrations above 500 pg/ml were associated with impaired longitudinal growth. Hence, the symptoms and management of the mineral and bone disorder of chronic kidney disease in children on peritoneal dialysis showed substantial regional variation. Our findings support a PTH target range of 100-300 pg/ml in the pediatric age group.

Treatment of focal glomerulosclerosis with pulse steroids and oral cyclophosphamide

Abstract. Patients with steroid-resistant nephrotic syndrome often have an unsatisfactory long-term outcome and are at risk of developing chronic renal failure. We prospectively treated 65 children with idiopathic steroid-resistant nephrotic syndrome and focal segmental glomerulosclerosis (FSGS) with intravenous pulses of corticosteroids and oral cyclophosphamide. Dexamethasone (5 mg/kg) or methylprednisolone (30 mg/kg) was administered intravenously, initially 6 pulses on alternate days, followed by 4 fortnightly and 8 monthly pulses. Oral cyclophosphamide therapy was given for 12 weeks and tapering doses of prednisolone were administered for 52 weeks. The mean age at treatment was 85.7± 44.9 months. Five patients developed serious infections during administration of initial alternate-day pulses and were excluded. Of 59 patients who completed initial alternate-day therapy, 17 had complete and 8 partial remission; 34 (57.6%) patients did not respond to treatment. The median urine protein to creatinine ratio decreased from 10.0 to 0.75 (P<0.005) and serum albumin increased from 1.9 g/dl to 2.4 g/dl (P<0.01). The median duration of follow-up after stopping pulse therapy was 25.6 months. Thirty-four patients were followed for more than 3 years (median 4.5 years). Of these, 22 (64.7%) patients had a favorable outcome; persistent complete remission was seen in 15 patients and steroid-responsive relapses in 7. Seven patients had non- nephrotic-range proteinuria, 2 had nephrotic-range proteinuria, and 3 (8.8%) were in chronic renal failure. There was no significant difference in the short- and long-term outcome of patients with initial (n=28) and late resistance (n=31). The outcome in patients receiving intravenous dexamethasone (n=48) or methylprednisolone (n=11) was also similar. The chief side effects included worsening of height standard deviation score (47.4%), transient hypertension (42.5%), and serious infections (18.5%). We conclude that prolonged treatment with intravenous corticosteroids and oral cyclophosphamide is beneficial in patients with steroid-resistant FSGS. Expensive protocols can be successfully modified and used, depending upon the availability of health resources.

Extending initial prednisolone treatment in a randomized control trial from 3 to 6 months did not significantly influence the course of illness in children with steroid-sensitive nephrotic syndrome

While studies show that prolonged initial prednisone therapy reduces the frequency of relapses in nephrotic syndrome, they lack power and have risk of bias. In order to examine the effect of prolonged therapy on frequency of relapses, we conducted a blinded, 1:1 randomized, placebo-controlled trial in 5 academic hospitals in India on 181 patients, 1-12 years old, with a first episode of steroid-sensitive nephrotic syndrome. Following 12 weeks of standard therapy, in random order, 92 patients received tapering prednisolone while 89 received matching-placebo on alternate days for the next 12 weeks. On intention-to-treat analyses, primary outcome of number of relapses at 1 year was 1.26 in the 6-month group and 1.54 in the 3-month group (difference -0.28; 95% confidence interval (CI) -0.75, 0.19). Relative relapse rate for 6- vs. 3-month therapy, adjusted for gender, age, and time to initial remission, was 0.70 (95% CI 0.47-1.10). Similar proportions of patients had sustained remission, frequent relapses, and adverse effects due to steroids. Adjusted hazard ratios for first relapse and frequent relapses with prolonged therapy were 0.57 (95% CI, 0.36-1.07) and 1.01 (95% CI, 0.61-1.67), respectively. Thus, extending initial prednisolone treatment from 3 to 6 months does not influence the course of illness in children with nephrotic syndrome. These findings have implications for guiding the duration of therapy of nephrotic syndrome.

Daily Corticosteroids Reduce Infection-associated Relapses in Frequently Relapsing Nephrotic Syndrome: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES Relapses of nephrotic syndrome often follow minor infections, commonly of the upper respiratory tract. Daily administration of maintenance prednisolone during intercurrent infections was examined to determine whether the treatment reduces relapse rates in children with frequently relapsing nephrotic syndrome. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS In a randomized controlled trial (nonblind, parallel group, tertiary-care hospital), 100 patients with idiopathic, frequently relapsing nephrotic syndrome eligible for therapy with prolonged low-dose, alternate-day prednisolone with or without levamisole were randomized to either receive their usual dose of alternate-day prednisolone daily for 7 days during intercurrent infections (intervention group) or continue alternate-day prednisolone (controls). Primary outcome was assessed by comparing the rates of infection-associated relapses at 12-month follow-up. Secondary outcomes were the frequency of infections and the cumulative amount of prednisolone received in both groups. RESULTS Patients in the intervention group showed significantly lower infection-associated (rate difference, 0.7 episodes/patient per year; 95% confidence intervals [CI] 0.3, 1.1) and lower total relapse rates (0.9 episodes/patient per year, 95% CI 0.4, 1.4) without increase in steroid toxicity. Poisson regression, adjusted for occurrence of infections, showed that daily administration of prednisolone during infections independently resulted in 59% reduction in frequency of relapses (rate ratio, 0.41; 95% CI 0.3, 0.6). For every six patients receiving this intervention, one showed a reduction of relapse frequency to less than three per year. CONCLUSIONS Daily administration of maintenance doses of prednisolone, during intercurrent infections, significantly reduces relapse rates and the proportion of children with frequently relapsing nephrotic syndrome.

Treatment with tacrolimus and prednisolone is preferable to intravenous cyclophosphamide as the initial therapy for children with steroid-resistant nephrotic syndrome

There are limited data on the relative efficacy and safety of calcineurin inhibitors and alkylating agents for idiopathic steroid-resistant nephrotic syndrome in children. To clarify this, we compared tacrolimus and intravenous cyclophosphamide therapy in a multicenter, randomized, controlled trial of 131 consecutive pediatric patients with minimal change disease, focal segmental glomerulosclerosis, or mesangioproliferative glomerulonephritis, stratified for initial or late steroid resistance. Patients were randomized to receive tacrolimus for 12 months or 6-monthly infusions of intravenous cyclophosphamide with both arms receiving equal amounts of alternate-day prednisolone. The primary outcome of complete or partial remission at 6 months, based on spot urine protein to creatinine ratios, was significantly higher in children receiving tacrolimus compared to cyclophosphamide (hazard ratio 2.64). Complete remission was significantly higher with tacrolimus (52.4%) than with cyclophosphamide (14.8%). The secondary outcome of sustained remission or steroid-sensitive relapse of nephrotic syndrome at 12 months was significantly higher with tacrolimus than cyclophosphamide. Treatment withdrawal was higher with cyclophosphamide, chiefly due to systemic infections. Compared to cyclophosphamide, 3 patients required treatment with tacrolimus to achieve 1 additional remission. Thus, tacrolimus and prednisolone are effective, safe, and preferable to cyclophosphamide as the initial therapy for patients with steroid-resistant nephrotic syndrome.