The value of direct radionuclide cystography in the detection of vesicoureteral reflux in children with normal voiding cystourethrography.

BACKGROUND: Vesicoureteral reflux (VUR) is one of the most important risk factors for urinary tract infection (UTI). Diagnosis and treatment of VUR is important to prevent irreversible complications, such as renal scarring and chronic renal failure. This study was conducted to assess the value of direct radionuclide cystography (DRNC) in the detection of VUR in children with UTI and a normal voiding cystourethrography (VCUG). METHODS: DRNC was performed in 35 children with a normal VCUG after an episode of febrile UTI who had hydronephrosis or hydroureter, abnormal acute dimercaptosuccinic acid (DMSA) scan results and/or febrile UTI recurrence. This study was conducted in the nephrology department of Mofid Children's Hospital, Tehran (Iran). RESULTS: The results were statistically analyzed. Among the 70 ureters studied, 33 (49.1 %) were observed to have VUR. Of these, 17 (51.5 %) had mild, 14 (42.4 %) moderate, and 2 (6.1 %) severe reflux. A significant relationship was observed between DRNC results and DMSA renal scan findings (P < 0.05). CONCLUSIONS: Based on our results, we suggest that DRNC may reveal VUR despite a normal VCUG in children with hydronephrosis, abnormal acute DMSA, and/or recurrent febrile UTI.

Urinary adrenomedullin level in children with acute pyelonephritis before and after treatment.

INTRODUCTION: Adrenomedullin (AM) is a 52-amino acid peptide that causes vasodilatation by increased synthesis of nitric oxide. Its production by different cells such as cardiac myocytes, smooth muscle, endothelial, and oncogenic cells is stimulated by inflammatory processes. It has been shown that in the presence of inflammation in the urinary system, concentration of AM increases. In this study, we measured urinary AM in children with acute pyelonephritis before and after treatment and compared its level with that in healthy children. MATERIALS AND METHODS: In a case-control study, 31 children with clinical and paraclinical documentation of pyelonephritis (case group) and 30 healthy children without pyelonephritis or other infections (control group) were studied. Urinary AM were measured on spot urine samples by high-performance liquid chromatography, and creatinine was measured by spectrophotometry to report the AM-creatinine ratio. RESULTS: Urinary AM-creatinine ratios were 61.3 +/- 119.4 pg/mg and 4.26 +/- 11.4 pg/mg, respectively, in the case and control groups (P = .01). After treatment of pyelonephritis in the patients of the case group, this ratio decreased to 13.1 +/- 21.9 (P = .048). The coefficient correlation between urinary AM and leukocytes count was 0.252 (P = .17). Urinary AM levels were 1896 +/- 1748 pg/dL and 391 +/- 477 pg/dL in the patients with 4+ versus negative C-reactive protein levels, respectively (P = .008). CONCLUSIONS: Urinary AM increases in the course of pyelonephritis and decreases significantly after treatment.

The role of dexamethasone on decreasing urinary cytokines in children with acute pyelonephritis.

Cytokines play a major role in renal scar formation following febrile urinary tract infection (UTI). We investigated the role of dexamethasone combined with antibiotics in diminishing urinary interleukin-6 (UIL-6) and UIL-8 concentrations during the acute phase of pyelonephritis compared with standard antibiotic therapy. UIL-6 and UIL-8 concentrations were determined by enzyme immunoassay in 34 children with pyelonephritis who were treated with ceftriaxone plus dexamethasone (case group) and in 20 patients with the same diagnosis treated with ceftriaxone alone (control group). Urine samples were obtained at the time of presentation prior to drug administration and at follow-up 72 h after initiation of medication. Creatinine concentrations were also determined, and cytokine/creatinine ratios were calculated to standardize samples. Differences between cytokine/creatinine ratios in initial and follow-up urine samples were significant in the case group (P < 0.001) but not for controls. In addition, combined antibiotic and dexamethasone significantly decreased UIL-6 and UIL-8 concentrations compared with antibiotic alone (P < 0.05). We conclude that dexamethasone combined with antibiotics significantly decreases UIL-6 and UIL-8 levels in patients with acute pyelonephritis. This suggests that the clinical use of corticosteroids may prevent scar formation following febrile UTI.