Haemolytic uremic syndrome surveillance in children less than 15 years in Belgium, 2009-2015.

BACKGROUND: The Haemolytic Uremic Syndrome (HUS) is the most severe manifestation of infection with Shiga toxin-producing Escherichia coli (STEC). In Belgium, the surveillance of paediatric HUS cases is conducted by a sentinel surveillance network of paediatricians called Pedisurv. In this article, we present the main findings of this surveillance from 2009 to 2015 and we describe an annual incidence of HUS. METHODS: For each case of HUS <  15 years notified by the paediatricians, clinical, microbiological and epidemiological data were collected by a questionnaire. National hospital discharge data with ICD-9 code 283.11 were used to calculate the incidence of HUS in children < 15 years. RESULTS: From 2009 to 2015, 110 cases were notified to the Pedisurv network with a mean annual notification rate of 0.8/100,000 in children < 15 years. Death occurred in 2.5% of all patients and the median number of days of hospitalization was 10 days. One third (35.4%) of the HUS cases were confirmed positive STEC, with a majority of STEC O157. The mean annual incidence based on the hospital discharge data was 3.2/100,000 in children < 15 years and 4.5/100,000 in children < 5 years. CONCLUSION: The incidence of paediatric HUS in Belgium is high compared to other European countries. Its surveillance in Belgium is quite comprehensive and, although less effective than monitoring all STEC infections to detect the emergence of outbreaks, is important to better monitor circulation of the most pathogenic STEC strains. In this context, efforts are still needed to send samples and STEC strains from HUS cases to the National Reference Centre.

Sleep-disordered breathing and proteinuria in overweight and obese children and adolescents.

OBJECTIVES: To assess whether sleep-disordered breathing (SDB) in overweight children and adolescents has an additional effect on the spectrum of urinary albumin to protein loss, as markers of early kidney dysfunction. METHODS: Prospective study in a clinical sample of overweight children and adolescents. Each subject underwent anthropometry, blood sampling, oral glucose tolerance test and polysomnography. From a 24-hour urine collection, albumin excretion rate and total urinary protein to creatinine ratio (UPCR) were calculated. RESULTS: 94 nondiabetic subjects were included (mean age = 11.0 +/- 2.5, 42 boys). Average BMI z-score was 2.25 +/- 0.47 (26 overweight subjects and 68 obese subjects). There was no difference in albumin excretion rate or UPCR between subjects with and without SDB. None of the SDB parameters correlated with the transformed albumin excretion rate or UPCR. Albumin excretion rate significantly correlated with fasting insulin and C-peptide and with post-challenge glucose, insulin and C-peptide levels, while UPCR correlated with fasting and post-challenge C-peptide levels. Multiple regression indicated that post-challenge glucose levels were the most important predictors of albumin excretion rate. CONCLUSION: Insulin resistance, and not SDB, was associated with increased levels of albuminuria, indicating early renal dysfunction, in this clinical sample of overweight children and adolescents.

Comparing a urea kinetic monitor with Daugirdas formula and dietary records in children.

The use of the online urea monitor has not been validated in children on hemodialysis. We compared online measured Kt/V(urea) and protein catabolic rate (PCR) with single- and double-pool Daugirdas formula (DF and eDF) based Kt/V(urea) and with protein intake derived from dietary records (DPI). In 8 children aged 8-18 years, 26 measurements were performed with the online urea monitor (UM 1000) with double-needle access. In 7 children, aged 4-14 years, 12 additional measurements were performed using single-needle dialysis. Pre-dialysis serum urea was determined by the monitor in equilibrated ultrafiltrate, obtained with ultrafiltration rates (UF) of 0.5 or 1.0 l/h, in 10 and 23 experiments respectively, and compared with the laboratory results. Urea determination in ultrafiltrate correlated well with blood sample urea: r=0.945 and 0.88 for UF rates of 0.5 l/h and 1.0 l/h, respectively. The correlation of online Kt/V with DF and eDF was 0.79 for double-needle and 0.21 for single-needle access. Bland-Altmann analysis showed a mean bias of 0.02 and 0.001, but levels of agreement of +0.3 and -0.3 for double-needle and +0.77 and -0.77 for single-needle dialysis respectively with DF. Maximum percentage error for double-needle access was 18% and 59% for single-needle access. The correlation of DPI with PCR was 0.5. A Bland-Altmann plot showed a mean bias of =0.22 with upper and lower limits of agreement of +0.55 and -0.1, respectively. Online urea kinetic modelling is feasible in children with double-needle hemodialysis only. Even with small dialyzers, an accurate serum urea measurement is obtained. PCR underestimates dietary protein intake.

Hyperhomocyst(e)inaemia in children with chronic renal failure.

BACKGROUND: Hyperhomocyst(e)inaemia has been identified as a significant risk factor for the occurrence of atherosclerosis in adults with chronic renal failure. Because of its presumed direct toxic effect on the vascular wall, long-standing hyperhomocyst(e)inaemia in children with chronic renal failure might have an important influence on their risk of future development of atherosclerosis. Hitherto no data on hyperhomocyst(e)inaemia in children with renal failure have been published. METHODS: We investigated 16 children with chronic renal failure on conservative management, 12 children on haemodialysis and 17 children with a renal transplant. Age-matched controls were used for comparison. Plasma homocyst(e)ine levels after an overnight fast were determined by HPLC. Glomerular filtration rate was estimated by the Schwartz formula. RESULTS: Mean plasma homocyst(e)ine levels were 12.6 +/- 5.2 micromol/l in the conservatively managed group, 22.2 +/- 13.5 micromol/l in the haemodialysed group, 14.2 +/- 2.1 micromol/l in transplanted children with an estimated GFR > 60 ml/min/1.73 m2 and 17.5 +/- 5.1 micromol/l in transplanted children with a lower estimated GFR. In all groups homocyst(e)ine levels were significantly elevated as compared to controls. Homocyst(e)ine levels were significantly correlated with age and negatively correlated with estimated GFR and serum folate levels. CONCLUSIONS: Hyperhomocyst(e)inaemia is a feature of chronic renal failure in children as well as in adults. Elevated homocyst(e)ine levels can already be demonstrated in children with renal failure before end-stage renal disease has developed and persist after renal transplantation. Whether treatment of hyperhomocyst(e)inaemia in children with renal failure decreases the risk for future atherosclerosis remains to be proven.

A retrospective epidemiological study of bacterial meningitis in an urban area in Belgium.

UNLABELLED: In order to obtain epidemiological data on the incidence of bacterial meningitis (BM) before the systematic introduction of vaccination against Haemophilus influenzae type b, a retrospective study of 124 children with proven BM was performed in an urban area in Belgium. N. meningitidis was the most prevalent cause, followed by H. influenzae and S. pneumoniae. Over a period of 6 years the incidence of BM increased ten fold, mainly due to an increase in N. meningitidis. The median age of the children with BM was 17 months and 35% of those with H. influenzae were younger than 1 year. Significant risk factors for BM as a whole were: age under 1 year, male gender, non-Caucasian descent and winter time. These findings may have implications for future vaccination policy in Belgium. CONCLUSION: Future vaccination schemes in Belgium should take into account than N. meningitis was the prevalent cause of bacterial meningitis and that certain factors increase the risk for developing bacterial meningitis.

Anti-glomerular basement membrane glomerulopathy in a young child.

We report the youngest patient with anti-glomerular basement membrane disease described in the literature to date. Age-dependent expression of the target antigen in this auto-immune disease explains the low incidence in young children. Despite adequate immunosuppression, renal function did not recover in our patient.

Hypophosphatemia in infants on continuous ambulatory peritoneal dialysis.

Three infants with irreversible renal failure and treated with continuous ambulatory peritoneal dialysis (CAPD) developed hypophosphatemia. In one of them rachitic lesions were observed on X-ray and bone biopsy showed osteomalacic osteodystrophy. Different mechanisms may have been at the origin of the hypophosphatemia: high doses of phosphate binders, low phosphorus intake, phosphate loss with the dialysate and possibly nutritional repletion. Dietary phosphorus restriction and use of phosphate binders should be applied with caution and serum phosphate should be monitored regularly in infants treated with CAPD.