Predictors of becoming overweight among pediatric patients at risk for urinary tract infections.

BACKGROUND: The association between obesity and urinary dysfunction in childhood has been described, albeit through retrospective analysis, making temporal relationships difficult to establish. OBJECTIVE: The objective of this study was to determine risk factors for significant weight gain in children at risk for recurrent urinary tract infections. STUDY DESIGN: A secondary analysis of the Randomized Intervention for Children with Vesicoureteral Reflux and Careful Urinary Tract Infection Evaluation trials was conducted. The outcome of interest in these children was significant increase in body mass index (BMI) percentile (>85th BMI percentile for sex and age) in previously normal-weight children. Multivariable logistic regression was used to determine the independent effects of predetermined risk factors. RESULTS: In total, 446 patients were included in the study. Most patients aged less than 1 year at study entry (229, 51%), and 399 (89%) of patients were female. Eighty-four patients (17%) became clinically overweight. Patients assigned to prophylactic antibiotics were not more likely to gain significant BMI percentiles (adjusted odds ratio [aOR] = 1.1, 95% confidence interval [CI]=0.6-1.8). Significant BMI percentiles were gained in Hispanic/Latino patients compared with whites (aOR = 3.3, 95% CI=1.7-6.4), in children who were infants at study enrollment compared with non-infants (aOR = 2.1, 95% CI=1.2-3.8), and in those with persistent reflux during the study period (aOR = 2.1, 95% CI=1.0-4.3). Neither patients assigned to prophylactic antibiotics (aOR = 1.1, 95% CI=0.6-1.8) nor patients with bladder and bowel dysfunction (BBD) (aOR = 1.2, 95% CI=0.6-2.3) were more likely to gain significant BMI percentiles. DISCUSSION: Significant BMI percentile gain is common in patients at risk for UTIs. Hispanic/Latino ethnicity, persistent reflux, and younger age, specifically infants than non-infants, were identified as independent risk factors for becoming overweight in this population. Exposure to prophylactic antibiotics and BBD were not associated with becoming overweight. CONCLUSION: Risk for becoming overweight should be discussed when managing patients at risk for UTIs, especially in the subpopulations identified.

Renal effect of vitamin D metabolites: evidence for the essential role of the 25(OH) group.

The effects of 1 alpha (OH)vitamin D3 [1 alpha (OH)D3] and 24,25(OH)2vitamin D3 [24,25(OH)2D3] on the phosphaturic action of parathyroid hormone (PTH) were studied in two groups of parathyroidectomized (PTX) rats. In group 1, PTX PTH-infused rats received intravenous 1 alpha (OH)D3, and in group 2, PTX PTH-infused rats received intravenous 24,25(OH)2D3. PTX PTH-infused rats served as controls. The effects of both vitamin D metabolites on renal PTH-activated adenylate cyclase (AC) were studied in vitro. In group 1, PTH increased fractional excretion of phosphate (CP/CIn) from 0.045 +/- 0.012 (+/- SE) to 0.263 +/- 0.011 (P less than 0.005). 1 alpha (OH)D3 failed to influence this response. In group 2, PTH increased CP/CIn from 0.055 +/- 0.008 to 0.289 +/- 0.027 (P less than 0.005). 24,25(OH)2D3 reduced the PTH-induced rise in CP/CIn from 0.289 +/- 0.027 to 0.192 +/- 0.021 (P less than 0.01) and decreased the urinary excretion of adenosine 3',5'-cyclic monophosphate. In vitro, 24,25(OH)2D3 blunted the PTH-activated AC, whereas 1 alpha (OH)D3 had no effect. These results show that 24,25(OH)D3, similar to two other 25(OH) metabolites of vitamin D-25(OH)vitamin D3 and 1,25(OH)2vitamin D3-suppresses the phosphaturic action of PTH, whereas 1 alpha(OH)D3, which is devoid of a 25(OH) group, lacks this effect. This suggests that a 25(OH) group is a prerequisite for the antiphosphaturic effect of vitamin D, whereas the 1 alpha (OH) group is not essential for this action.

Effects of subminimal inhibitory concentrations of chloramphenicol, erythromycin and penicillin on group A streptococci.

Group A streptococci strains were grown in broth containing subminimal inhibitory concentrations of chloramphenicol, erythromycin and penicillin, and tested for possible changes in colonial morphology, activity and amount of cellular and extracellular components. The following components were tested: T protein, M protein, opacity factor, lipoteichoic acid, hyaluronic acid, streptolysin S, streptolysin O, DNase, hyaluronidase and NADase. Sub-MICs of these drugs produced variable changes in the bacteria. They increased the amount of hyaluronic acid and hyaluronidase, decreased the amount of M protein, and enhanced phagocytosis and the release of lipoteichoic acid. The results indicate that sub-MICs of chloramphenicol, erythromycin and penicillin may affect the pathogenicity and toxinogenicity of group A streptococci.