Israel Medical Association Journal

Background: Several studies link the pathogenesis of nephrotic syndrome to tumor necrosis factor-alpha (TNFα). However, data on the serum TNFα level in children with nephrotic syndrome are sparse. 

Objective: To investigate serum TNFα levels and the effect of steroid therapy in children with nephrotic syndrome. 

Methods: A prospective cohort pilot study of children with nephrotic syndrome and controls was conducted during a 1 year period. Serum TNFα levels were measured at presentation and at remission, or after a minimum of 80 days if remission was not achieved.

Results: Thirteen patients aged 2–16 years with nephrotic syndrome were compared with 12 control subjects. Seven patients had steroid-sensitive and six had steroid-resistant nephrotic syndrome. Mean baseline serum TNFα level was significantly higher in the steroid-resistant nephrotic syndrome patients than the controls (6.13 pg/ml vs. 4.36 pg/ml, P = 0.0483). Mean post-treatment TNFα level was significantly higher in the steroid-resistant than in the steroid-sensitive nephrotic syndrome patients (5.67 pg/ml vs. 2.14 pg/ml, P = 0.001). In the steroid-resistant nephrotic syndrome patients, mean serum TNFα levels were similar before and after treatment.

Conclusions: Elevated serum TNFα levels are associated with a lack of response to corticosteroids. Further studies are needed to investigate the role of TNFα in the pathogenesis of nephrotic syndrome.

 

Background: The incidence of post-infectious glomerulonephritis (PIGN) has decreased over the last decades. As a result, recent epidemiological data from industrialized countries are scarce. 

Objectives: To evaluate patterns of PIGN in children and detect possible predictors of disease severity.

Methods: We collected clinical and laboratory data of patients with PIGN admitted to Schneider Children's Medical Center during 1994–2011. Diagnostic criteria included presence of hematuria with/without other features of nephritic syndrome along with hypocomplementemia and/or microbiological/serological evidence of streptococcal infection. Patients with other diseases (systemic lupus erythematosus, vasculitis, etc.) were excluded from the study. 

Results: A total of 125 patients with a mean age of 5.8 ± 3.3 years (range 1.5–17.6), of whom 16% were < 3 years, matched the study criteria. Presenting features included hypertension in 103 (82.4%) patients, azotemia in 87 (70.2%), fever in 49 (40%), and elevated C-reactive protein in 75 (81.5%). Isolated macrohematuria was found in 21 (16%). Full-blown nephritic syndrome was diagnosed in 51 patients (41.1%) and 28 (22.9%) had nephritic syndrome with nephrotic-range proteinuria. Depressed C3 complement levels were associated with the presence of nephritic syndrome (OR 0.73, 95%CI 0.60–0.88, P = 0.001) as well as older age (OR1.24, CI 1.08–1.43, P = 0.001). At last follow-up (mean 42 months) all examined patients (100 of 125) had normal renal function, 6 had hypertension, and 1 had proteinuria.

Conclusions: PIGN remains an important cause of glomerular disease in children and may affect very young patients. Nephrotic-range proteinuria with hypoalbuminemia seems to be more frequent than previously reported. Hypocomplementemia is associated with a more severe disease course, namely, azotemia and nephritic syndrome. 

 

Background: Acute renal failure (ARF) is a common complication in critically ill children. It is known as an important predictor of morbidity and mortality in this population. Data on the factors affecting the choice of renal replacement therapy (RRT) modality and its impact on mortality of children with ARF[1] are limited.

Objectives: We retrospectively studied 115 children with ARF necessitating RRT[2] during the period 1995–2005 to evaluate the effect of several prognostic factors as well as RRT type on their immediate outcome.

Methods: The data collected from charts included demographics, primary disease, accompanying medical conditions, use of vasopressor support, indications for dialysis, RRT modality, and complications of dialysis. Categorical variables were analyzed using chi-square or Fisher’s exact tests. Variables associated with mortality (P < 0.1) at the univariable level were studied by a multivariable logistic regression model.

Results: The most common cause of ARF was congenital heart disease (n=75). RRT modalities included peritoneal dialysis (PD) (n=81), hemodialfiltration (HDF) (n=31) and intermittent hemodialysis (IHD) (n=18). Median RRT duration was 4 days (range 1–63 days). Overall mortality was 52.2%. IHD[3] was associated with the best survival rate (P < 0.01 vs. PD[4] and HDF[5]), while children treated with HDF had the worse outcome. Hemodynamic instability and systemic infections were associated with greater mortality, but the rate of these complications did not differ between the study groups.

Conclusions: Our results suggest that IHD[6] when applied to the right patient in an appropriate setting may be a safe and efficient RRT modality in children with ARF. Randomized prospective trials are needed to further evaluate the impact of different RRT modalities on outcome in children with ARF.

Background: Peritonitis is a major complication of chronic peritoneal dialysis therapy. It is recommended that each center monitor infection rates in order to define the local microbiological profile and implement an appropriate empiric antibiotic regimen.

Objectives: To analyze the microbiological profile of peritonitis in our pediatric dialysis unit and identify local predisposing factors.

Methods: In this retrospective study we reviewed the files of children treated with chronic PD[1] during the 10 year period 1997–2007.

Results: Eighty peritonitis episodes were recorded in 29 children (20 male, 9 female) aged 0.1–18.5 years (median 11.75) treated with peritoneal dialysis for 6–69 months (median 19) for a total of 578 patient-months. The annual peritonitis rate was 1.66/patient. The main pathogens were coagulase-negative Staphyloccocus (32.5%) and Pseudomonas spp. (16%), which were also cultured in most cases (64–69%) from the exit site during the 3 months preceding peritonitis. No peritonitis occurred in 31% of the patients (median age 12.5 years). All patients less than 5 years old had at least one peritonitis episode. Contaminating conditions (gastrostomy, enuresis, diaper use), found in 44% of the study group, and first infection within 6 months from starting PD were significantly associated with an increased peritonitis rate (P = 0.01, P = 0.009, respectively). Recurrent peritonitis led to a switch to hemodialysis in 18% of patients. There were no deaths.

Conclusions: The risk factors for peritonitis in our study were: first infection within less than 6 months from starting treatment, Pseudomonas exit-site colonization, and contaminating conditions (gastrostomies, diaper use, enuresis). These susceptible subgroups as well as very young age (< 5 years) at starting PD should be especially targeted during training of caregivers and follow-up to prevent later complications.  

[1] PD = peritoneal dialysis

Background: Although febrile urinary tract infections are very common in young children, the need for antimicrobial prophylaxis and evaluation following a first event is controversial.

Objectives: To assess the approach of leading pediatric specialists throughout Israel.

Methods: A questionnaire regarding the approach to antibiotic prophylaxis and diagnostic evaluation following a first event of febrile UTI[1], according to age and underlying renal abnormality, was sent to all 58 directors of departments of pediatrics, units of pediatric infectious diseases and pediatric nephrology in Israel.

Results: Fifty-six directors (96%) responded. Most prescribed prophylactic antibiotics after UTI. Heads of infectious disease departments prescribed less prophylaxis following UTI at the age of 18 months than heads of pediatrics or heads of pediatric nephrology units (34% vs. 72–75%, P = 0.018), but more often in cases of severe vesico-ureteral reflux without UTI. Cephalosporins were used prophylactically more often by directors of pediatrics compared to heads of pediatric nephrology units (71% vs. 38%, P = 0.048); the latter used non-beta-lactam prophylaxis (61% vs. 23%, P = 0.013) more often. Most pediatricians used renal sonography for evaluation; renal scan was used more commonly by pediatric nephrologists.

Conclusions: The administration of prophylactic antibiotics after UTI is still common practice among pediatric opinion leaders, although the specific approach differs by subspecialty. According to up-to-date evidence-based data, educational efforts are needed to formulate and implement judicious guidelines.