Genetic variations of interleukin-8, CXCR1 and CXCR2 genes and risk of acute pyelonephritis in children.

Acute pyelonephritis (APN) is the most severe form of urinary tract infection, the etiopathogenesis of which is still not well understood. Previous studies demonstrated that chemotaxis of neutrophils into the tissue and across the infected epithelial layer is a key step in rapid bacterial clearance. Variations within genes encoding the major chemokine interleukin-8 and its receptors CXCR1 and CXCR2 are therefore attractive candidates for participation in genetic predisposition to APN. The aim of our study was to evaluate the association of single nucleotide polymorphisms (SNPs) -251 T/A, +781 C/T, +1633 C/T and +2767 A/T in the IL-8 gene, +2608 G/C in the CXCR1 gene and +1208 C/T in the CXCR2 gene with susceptibility to APN in the Slovak population. PCR-SSP and PCR-RFLP were used to genotype SNPs in 147 children with APN (62 with recurrent and 85 with episodic form) and 215 healthy individuals. Statistical analysis revealed significantly increased frequency of CXCR1 +2608 C allele (P = 0.0238, OR = 2.452, 95% CI = 1.147-5.243) and GC genotype (P = 0.0201, OR = 2.627, 95% CI = 1.188-5.810) and lower frequency of CXCR2 +1208 T allele (P = 0.0408, OR = 0.645, 95% CI = 0.429-0.972) and TT+TC genotypes (P = 0.0497, OR = 0.5273, 95% CI = 0.288-0.964) in patients with recurrent APN compared with healthy controls. Furthermore, the A allele of IL-8 -251 T/A SNP was also significantly overrepresented in patients with recurrent APN when compared with those with only single episode of APN (P = 0.0439, OR = 1.627, 95% CI = 1.019-2.599). Our results indicate that the minor CXCR1 +2608 C allele is associated with significantly increased susceptibility to APN in childhood, while the CXCR2 +1208 T allele confers protection from recurrent APN. Moreover, allele A of the IL-8 -251 T/A may also increase the risk of developing recurrent attacks after the first-time APN.

A successful therapy of renovascular hypertension.

Authors describe a rare cause, diagnostic difficulties and successful therapy of renovascular hypertension in a 12 year-old girl caused by anular stenosis of the intrarenal arterial branch. Activation of the system renin-angiotensin (RAS) is found in all forms of renovascular hypertension at the beginning. Etiologically, stenosis in childhood is caused mostly by renal artery dysplasia, affecting mostly media, and fibromuscular dysplasia. Fibromuscular dysplasia affects middle and distal third of renal artery in 60%, more frequently on right, only in 10% of cases affects segmental branches; one quarter of patients are affected bilaterally. This disease is found predominantly in young women. During clinical course, typical signs include sudden onset of severe and poorly controlled hypertension, renal insufficiency, proteinuria and hypertensive retinopathy. From non-invasive diagnostic approaches, color duplex ultrasound, NMR and CT angiography are important, from invasive ones, digital subtractive angiography and the measurement of plasma rennin activity in renal veins. In therapy, it is percutaneous transluminal renal angioplasty, associated with low mortality and morbidity. The net result of angioplasty is dilation of stenosis, complete restoration of artery lumen and flow and decrease of blood pressure. The best results can be achieved in young patients with fibromuscular dysplasia, more then half can recover completely. Using this method, also our patient has recovered (Tab. 2, Fig. 2, Ref. 7).

[Peritoneal dialysis in children after cardiac surgery]. / Peritoneálna dialýza u detí po kardiochirurgických operáciách.

The authors analyse their experience with the use of peritoneal dialysis (PD) in children with acute renal failure after cardiac surgery. From 1995 through 1998, 1246 children were operated in Pediatric Cardiocenter 38 of them developed acute renal failure and required peritoneal dialysis. Indications for PD were oliguria, anuria, hyperkalemia and fluid overload with generalized tissue oedema. PD was instituted at mean 33.9 (3-132) hours after surgery and lasted mean 53.7 (6-264) hours. None of the patients developed peritoneal infection. Hyperglycaemia developed in 8 patients and was treated with continuous insulin infusion. 5 patients required catheter reposition or reinsertion due to inadequate fluid removal and 1 patient required another renal replacement therapy. 22 (57.9%) patients died due to intractable low cardiac output. 16 survivors recovered their renal functions. In a long-term follow-up, 7 patients had no signs of significant renal dysfunction. In 4 patients, mild elevation of N-acetyl-beta-D-glukozaminidase indicates mild proximal tubular dysfunction. These findings together with aminoaciduria in 5 patients will require a further follow-up. (Tab. 2, Fig. 1, Ref. 16.)

[Abdominal pain in childhood caused by stenosis of the pyelo-ureteral junction]. / Bolesti brucha v detskom veku spôsobené stenózou pyeloureterálnej junkcie.

The authors describe three patients with episodes of abdominal pain where despite a negative finding in the urine sonography revealed dilatation of the hollow system. Urography proved stenosis of the pyeloureteral junction. The authors discuss the cause of abdominal pain. Consistent with data in the literature, the authors draw attention to pitfalls in the diagnosis of hydronephrosis. They recommend sonographic examination of children with abdominal pain, as a negative urinary finding does not rule out hydronephrosis. In this respect screening of hydronephrosis and other obstructive anomalies during the neonatal period is an advantage.

[Hyperechogenic renal pyramids in children]. / Hyperechogénne renálne pyramídy u detí.

The authors describe the case-histories of four children with hyperechogenic renal pyramids. These children are followed up at the First Paediatric Clinic in Bratislava.