Journal of pediatric nephrology
Volume:2 Issue: 4, Autumn 2014

In children with chronic kidney disease (CKD), growth retardation is not a rare problem. Factors such as malnutrition, anemia, metabolic acidosis, inadequate dialysis and growth hormone resistance may cause growth failure in these children. Growth stimulation in these children can be done by supraphysiologic doses of recombinant human GH (rhGH). It stimulates growth in prepubertal CKD children, in end-stage renal disease, and after kidney transplantation. Its underlying mechanism may be the reversal of hypercatabolic state of uremia or increases in the circulating level of insulin-like growth factor (IGF). We recommend starting the treatment when the patient height falls below the third percentile and spontaneous catch-up growth does not happen despite stabilization of other contributing factors. It is better to start rhGH therapy at a young age because there is a better response in preterminal CKD than those on dialysis. We use rhGH in CKD children at a dose of 0.045 to 0.05 mg/kg/day subcutaneously every evening and a height taller than the third percentile of the general population is our minimal goal.

The inflammatory reaction caused by a pyelonephritis infection can result in renal injury or scarring, which is also termed reflux-related renal injury or reflux nephropathy. The importance of platelet changes is emphasized in some chronic diseases. In this study, the changes of mean platelet volume (MPV) and mean platelet count (MPC) were investigated in children with reflux nephropathy. In this case-control study, 107 females with vesicoureteral reflux (VUR) (grade 1 to 3) and reflux nephropathy and 107 females with VUR (grade 1 to 3) without reflux nephropathy were included. Demographics characteristics of the patients were recorded and laboratory parameters in the active phases of first pyelonephritis were evaluated. MPC was higher in patients with reflux nephropathy than non-reflux nephropathy patients and MPV was lower in the patients with reflux nephropathy than patients without reflux nephropathy. MPV can be used as an indicator in diagnosis of reflux nephropathy in patients with VUR.

Deficiencies of water soluble vitamins such as folate and vitamin B12 has been reported as etiologic factors of hyperhomocysteinemia. This study was conducted to find whether there is a correlation between serum levels of these vitamins and plasma total homocysteine (tHcy) levels. 19 hemodialysis subjects were enrolled. The study group comprised 52.6% girls and 47.4% boys aged 80-324 (204.7±78.4) months who were on dialysis from 1.5-153 (42.1±43.3) months ago. All patients were supplemented by folate and 15 cases were received oral vitamin B12.Folate serum levels <1.5 ng/ml were defined as low (deficiency).As for vitamin B12, levels < 120 pg/ml, 120-160 pg/ml were defined as deficient and borderline, respectively. Plasma Hcy levels of 5-15 µmol/L and > 15 µmol/L were defined as normal and hyperhomocysteinemia, respectively. The correlation between the serum levels of vitamins and plasma Hcy levels was checked by the Pearson correlation test and P-values <0.05 and r>0.7 indicated a good (significant) correlation. 13 patients (68.4%) had hyperhomocysteinemia whereas plasma tHcy levels were normal in 6 (31.6%). No patient had folate or vitamin B12 deficiency.There was no correlation between tHcy levels and serum vitamin B12 (P=0.621, r=1) and serum folate levels (P=0.571, r=1). Normal and even high serum levels of folate and vitamin B12 cannot prevent the occurrence of hyperhomocysteinemia in hemodialysis patients.

Hypercalciuria has been considered a predisposing factor for recurrent urinary tract infection (UTI) in recent studies. The mechanism may be related to uroepithelial injury by calcium microcrystals. The aim of this study was to evaluate the association of idiopathic hypercalciuria with recurrent UTI in children. In this cross-sectional study, the urine calcium/creatinine ratio of 40 children aged 2-16 years with recurrent urinary tract infection (without urinary tract anomalies and voiding dysfunction) was compared with 40 age- and sex-matched healthy children. Hypercalciuria was defined as a calcium/creatinine ratio more than 0.21 in a spot urine test. Recurrent UTI was defined as at least 3 episodes of UTI during 1 year or 2 episodes in 6 months. The mean age of the patients was 5±2.22 years and mean age of the control group was 5.13±1.98 years. The mean calcium/creatinine ratio in the case group (0.21±0.17) was significantly higher than the control group (0.08±0.08) (p<0.05). Hypercalciuria was detected in 47.5% of the patients in the case group and in 7.5% of the participants in the control group (P<0.001). The history of familial urolithiasis was positive in 21% of the hypercalciuric patients. There was no significant difference in the frequency of urinary symptoms between hypercalciuric and normocalciuric patients with recurrent UTI. The episodes of UTI reduced in 12/19 (63.2%) of the patients after the treatment of hypercalciuria. Children who suffer from recurrent UTI in the absence of urinary tract anomalies should be checked for hypercalciuria. Control of hypercalciuria may decrease UTI episodes.

Magnetic Resonance Urography (MRU) is a popular method for identifying uropathies in children. Some children are not cooperative for such examinations and are sedated. We decided to evaluate the effects of midazolam as a sedative drug on ureter visualization in patients undergoing MRU. The study was conducted in Paytkaht Medical Imaging Center, Tehran, Iran. Two hundred and three children with urologic diseases were divided into 2 groups. Patients in the non-cooperative group received midazolam prior to MRU. Our findings showed that non-cooperative children had a better ureter visualization on MRU (P<0.01). Midazolam increased ureter visualization possibly by reduction in the ureter peristaltic motility. Therefore, its use could shorten the duration of MRU. It is beneficial to use midazolam in all children who undergo MRU.

Atypical hemolytic uremic syndrome (aHUS) is a rare and life-threatening disease that may lead to end-stage renal failure (ESRF) or death, and may be accompanied by a variety of extrarenal manifestations. We presented a child with aHUS accompanied by severe extrarenal manifestations. A 12-year-old girl was visited in the emergency departments with acute renal failure, symptoms of fluid overload, vomiting, and somnolence. Laboratory tests revealed microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure with severe electrolyte imbalance. Diagnosis of HUS was made and emergency hemodialysis was performed to decrease the circulating volume, restore the electrolyte disturbance, and support the treatment of HUS, but conventional medical therapies were ineffective. The patient experienced frequent seizures and multiple cardiac arrests and became comatose. Thereafter, although she was diagnosed with aHUS, plasma infusions and plasmapheresis were performed. Upper gastrointestinal endoscopy and colonoscopy revealed erosive pangastritis, widespread gastric hemorrhagic ulcers, bulbitis, and hemorrhagic colitis. Since there was no improvement, the patient was transferred to a central university hospital where eculizumab was started. She responded to eculizumab. In conclusion, as aHUS can progress rapidly and is frequently fatal if untreated, it is important to be aware of unusual presentations and diagnose the condition promptly, particularly if supportive treatment is of little or no help.

Solitary crossed renal ectopia is a rare anomaly of the urinary tract. This anomaly is often diagnosed incidentally when patients are being evaluated for other associated findings including genitourinary, cardiovascular, hematological or vertebral abnormalities. We report a boy with solitary crossed renal ectopia that was considered a solitary normal positioning kidney by ultrasonography and dimercaptosuccinic acid scan. However, voiding cystourethrogram revealed vesicoureteral reflux and crossed ectopia. Therefore, in any normal appearing solitary kidney, crossed ectopia may be a possible finding.