Changes in Bacterial Resistance Patterns of Pediatric Urinary Tract Infections and Rationale for Empirical Antibiotic Therapy.

BACKGROUND: The causative agent spectrum and resistance patterns of urinary tract infections in children are affected by many factors. AIMS: To demonstrate antibiotic resistance in urinary tract infections and changing ratio in antibiotic resistance by years. STUDY DESIGN: Retrospective cross-sectional study. METHODS: We analysed antibiotic resistance patterns of isolated Gram (-) bacteria during the years 2011-2014 (study period 2) in children with urinary tract infections. We compared these findings with data collected in the same centre in 2001-2003 (study period 1). RESULTS: Four hundred and sixty-five uncomplicated community-acquired Gram (-) urinary tract infections were analysed from 2001-2003 and 400 from 2011-2014. Sixty-one percent of patients were female (1.5 girls : 1 boy). The mean age of children included in the study was 3 years and 9 months. Escherichia coli was the predominant bacteria isolated during both periods of the study (60% in study period 1 and 73% in study period 2). Bacteria other than E. coli demonstrated a higher level of resistance to all of the antimicrobials except trimethoprim-sulfamethoxazole than E. coli bacteria during the years 2011-2014. In our study, we found increasing resistance trends of urinary pathogens for cefixime (from 1% to 15%, p<0.05), amikacin (from 0% to 4%, p<0.05) and ciprofloxacin (from 0% to 3%, p<0.05) between the two periods. Urinary pathogens showed a decreasing trend for nitrofurantoin (from 17% to 7%, p=0.0001). No significant trends were detected for ampicillin (from 69% to 71%), amoxicillin-clavulanate (from 44% to 43%), cefazolin (from 39% to 32%), trimethoprim-sulfamethoxazole (from 32% to 31%), cefuroxime (from 21% to 18%) and ceftriaxone (from 10% to 14%) between the two periods (p>0.05). CONCLUSION: In childhood urinary tract infections, antibiotic resistance should be evaluated periodically and empiric antimicrobial therapy should be decided according to antibiotic sensitivity results.

Biochemical bone markers in nephrotic children.

In this study we evaluated the effects of high-dose corticosteroid (CS) therapy and the character of the nephrotic syndrome (NS) itself on bones in patients with normal glomerular filtration rate. We measured serum osteocalcin (OC), alkaline phosphatase (ALP), intact parathyroid hormone (iPTH), 25-hydroxyvitamin D, calcium (Ca), phosphorus (P), and magnesium (Mg) levels, and urinary Ca and protein excretion in nephrotic children during the active phase before (group Ia) and after CS treatment (group Ib). The results were compared with age-matched control subjects. A significant increase in urinary Ca excretion was observed after CS treatment. Serum ALP, OC, and iPTH levels were within normal limits at the time of study entry. However, both serum OC and ALP levels showed a significant decrease after the completion of CS treatment (OC from 13.6+/-9.2 ng/ml to 6.7+/-5.2 ng/ml and ALP from 151.8+/-60.2 U/l to 116+/-43.8 U/l). 25-Hydroxyvitamin D levels increased to 17.2+/-8.9 microg/l from 9.9+/-6.9 microg/l after CS treatment. The effects of recurrent use of CSs were assessed by dividing nephrotic patients into two subgroups: infrequent relapsers (IFR) and frequent relapsers (FR). The cumulative dose of CS was 28,125 mg/m(2) for IFR and 105,000 mg/m(2) for FR. The changes in OC, ALP, and 25-hydroxyvitamin D levels after CS treatment were significantly different between IFR and FR. We conclude that high-dose CS treatment causes a decrease in bone formation, as shown by the changes in OC and ALP levels. 25-Hydroxyvitamin D levels remained lower than control subjects after CS therapy. The higher the cumulative dose of CS used the more marked the changes in biochemical bone markers. The contribution of FR to baseline 25-hydroxyvitamin D levels needs further study.