Angiotensin II type 2 receptor gene polymorphism in Caucasian children with a wide spectrum of congenital anomalies of the kidney and urinary tract.

The A-1332G transition of the angiotensin II type 2 receptor (AT2R) gene was found to occur more often in males with ureteropelvic (UPJO) or ureterovesical junction obstruction (UVJO). However, other studies have shown controversial results. Tauhe frequency of this polymorphism was investigated in 275 Caucasian children (153 boys, 122 girls) with a wide spectrum of congenital anomalies both of upper (165) and lower (110) urinary tract system and in 200 controls (100 boys, 100 girls). Among the included malformations, renal agenesis and duplex collecting system (DCS) were studied for the first time. The frequency of the G allele did not differ among patients (193 of 397 total alleles, 48.6%) and controls (146 of 300, 48.7%). No significant difference was also found in the frequency of the G allele in subgroups of congenital uropathies compared with controls. When analysis was performed in males and females separately, no significant difference was found in the frequency of the G allele in male (45.1%) or female (50.8%) patients compared with male (57.0%) or female (44.5%) controls. Our data indicate that the AT2R gene A-1332G transition is not associated with the development of human congenital uropathies and further investigations should be carried out to unravel their etiology.

Duplex collecting system diagnosed during the first 6 years of life after a first urinary tract infection: a study of 63 children.

PURPOSE: We determined the prevalence, anatomical variants and coexisting complications of duplex collecting systems in children with a history of UTI. Additionally, we compared the prevalence and severity of the coexisting anomalies with those found in single systems. MATERIALS AND METHODS: We reviewed the records of children younger than 6 years who were evaluated following a first UTI during a 9-year period to identify those with duplex systems. Children without duplication anomalies comprised the control group. RESULTS: Of 774 evaluated children 63 (8%), more commonly females than males, had duplex systems. CDS were as common as IDS. VUR was the most commonly associated anomaly, with a higher prevalence in CDS (66%) and IDS (47%) compared to single systems (26%, p <0.0001 and p = 0.007, respectively). Ectopic ureterocele, which was the second most common associated anomaly, was found in 20% of the CDS but in none of the IDS or single systems. The occurrence of renal scarring was similar among CDS, IDS (13%) and single systems (10%). Poorly functioning pole moieties occurred more often in CDS (40%) compared to IDS (4%, p = 0.003), and were observed in none of the single systems. The resolution rate of reflux tended to be higher in IDS compared to CDS. CONCLUSIONS: CDS were a common finding among children with UTI who had duplication anomalies. Although CDS and IDS were accompanied by VUR more often than were single systems, CDS were associated more often with severe VUR, other serious complications and poor renal function.

Rare causes of acute hyperkalemia in the 1st week of life. Three case reports.

We describe three neonates with hyperkalemia and renal salt wasting during the 1st week of life. Endocrinological evaluation led to the diagnosis of selective hypoaldosteronism (HA) in two neonates and secondary pseudohypoaldosteronism (PHA) in one. The infant with PHA developed a urinary tract infection, and radiological investigation demonstrated a small dysplastic left kidney with vesicoureteral reflux. The electrolyte and hormonal disturbances in this infant persisted throughout the first months of life. The two infants with selective HA improved rapidly after administration of fludrocortisone orally and the electrolytes and renin values returned to normal. Secondary PHA and selective HA should be considered in the differential diagnosis in salt-losing neonates during the first days of life. Renal ultrasonography, urine culture, and assays of aldosterone and plasma renin activity should be performed in any infant presenting with hyperkalemia and salt wasting after the exclusion of congenital adrenal hyperplasia.

Acute nephritis and respiratory tract infection caused by Mycoplasma pneumoniae: case report and review of the literature.

A 6-year-old boy presented with an acute infection caused by Mycoplasma pneumoniae associated with respiratory tract and kidney involvement. Renal manifestations included acute nephritis with decreased C3 fraction of serum complement, occurring concomitantly with the respiratory symptoms. The child had an excellent outcome, with rapid normalization of C3 and complete resolution of the acute nephritis.