Theresa A. Schlager

Effect of cranberry juice on bacteriuria in children with neurogenic bladder receiving intermittent catheterization

OBJECTIVE To determine the effect of cranberry prophylaxis on rates of bacteriuria and symptomatic urinary tract infection in children with neurogenic bladder receiving clean intermittent catheterization. DESIGN Double-blind, placebo-controlled, crossover study of 15 children receiving cranberry concentrate or placebo concentrate for 6 months (3 months receiving one concentrate, followed by 3 months of the other). Weekly home visits were made. During each visit, a sample of bladder urine was obtained by intermittent catheterization. Signs and symptoms of urinary tract infection and all medications were recorded, and juice containers were counted. RESULTS During consumption of cranberry concentrate, the frequency of bacteriuria remained high. Cultures of 75% (114 of 151) of the 151 samples obtained during consumption of placebo were positive for a pathogen (>/=10(4) colony-forming units/mL) compared with 75% (120 of 160) of the 160 samples obtained during consumption of cranberry concentrate. Escherichia coli remained the most common pathogen during placebo and cranberry periods. Three symptomatic infections each occurred during the placebo and cranberry periods. No significant difference was observed in the acidification of urine in the placebo group versus the cranberry group (median, 5.5 and 6.0, respectively). CONCLUSION The frequency of bacteriuria in patients with neurogenic bladder receiving intermittent catheterization is 70%; cranberry concentrate had no effect on bacteriuria in this population.

Bacteriuria in children with neurogenic bladder treated with intermittent catheterization: Natural history

OBJECTIVE To determine whether bacteriuria unassociated with symptoms in patients with neurogenic bladder will lead to symptomatic infection and/or deterioration of the upper urinary tract if left untreated, we examined whether bacteriuria persisted in bladder urine of children with neurogenic bladder treated with clean intermittent catheterization (CIC) and whether persistence of bacteria led to symptomatic infection or deterioration of the upper urinary tract. DESIGN Weekly home visits were made during 6 months of surveillance of 14 children on the CIC regimen with a normal upper urinary tract and no reflux (as determined by renal ultrasonography, voiding cystourethrography, and serum creatinine measurement). During visits a sample of bladder urine was obtained by CIC, and signs and symptoms of urinary tract infection and all medications were recorded. RESULTS Fourteen children were observed for 323 weeks. Cultures of 70% (172/244) of the urine samples collected were positive for organisms (> or = 10(4) colony-forming units per milliliter), 152 (88%) for the usual pathogens and 20 (12%) for commensal organisms. Bacteriuria was associated with pyuria two thirds of the time, regardless of bacterial species. Carriage of the same pathogen for 4 weeks or longer, with associated pyuria, was common during surveillance. Despite frequent episodes of bacteriuria with associated pyuria, there were only five symptomatic infections during the 323 patient-weeks. Children remained clinically well during the study period, and their upper urinary tract did not deteriorate. CONCLUSION Bacteriuria persists for weeks in symptom-free children being treated with CIC for neurogenic bladder associated with a normal upper urinary tract. Before attempts are made to eradicate bacteriuria, treatment should be proved to be beneficial to this population.

Clonal Diversity of Escherichia coli Colonizing Stools and Urinary Tracts of Young Girls

ABSTRACT Intestinal carriage of Escherichia coli in prepubertal girls without a history of urinary tract infection was examined by collecting weekly stools and periurethral and urine samples over 3 to 4 weeks of study. Dominant and minor clones were defined by grouping 28 E. coli isolates into clonal types. Multiple enteric clones of E. coli, which changed week to week, were found in the 13 girls during the study (median, 3 clones/girl; range, 1 to 16 clones/girl). Dominance of an enteric clone did not predict persistence in the stool. In only 10 (34%) of the 29 episodes in which a dominant clone present in one weekly sample could have been detected the following week did it persist as the dominant clone in the next weekly sample. In 5 (17%) of the 29 episodes, a dominant clone found in one weekly sample was classified as a minor clone the next week. Both dominant and minor clones were observed to colonize the urinary tract. However, when colonization of the periurethra or bladder urine occurred, it was brief and often did not reflect the dominant stool flora from the same week. In fact, in only 40% of episodes was a clone that was detected either on the periurethra or in the urine also recovered from the stool the same week. Our findings suggest that the intestinal flora of healthy girls is multiclonal with frequent fluctuations in composition.

Nitrofurantoin prophylaxis for bacteriuria and urinary tract infection in children with neurogenic bladder on intermittent catheterization

OBJECTIVE To determine the effect of nitrofurantoin prophylaxis on rates of bacteriuria and symptomatic urinary tract infection in children with chronic neurogenic bladder receiving clean intermittent catheterization. DESIGN Double-blind, placebo-controlled, crossover trial of 15 children receiving nitrofurantoin or placebo for 11 months (5 months receiving one drug, then 1 month of washout followed by 5 months of the alternate drug). Weekly home visits were made. During each visit a sample of bladder urine was obtained by intermittent catheterization, signs and symptoms of urinary tract infection were recorded, and all medications were recorded as well as a capsule count of the study drug. RESULTS During nitrofurantoin the frequency of bacteriuria remained high. Cultures of 74% (203 of 274) of the 274 samples on placebo were positive for a pathogen (> or = 10(4) colony-forming units per milliliter) compared with 65% (165 of 252) of the 252 samples on nitrofurantoin. The bacterial species responsible for bacteriuria, however, were altered; Escherichia coli, the most common pathogen isolated during placebo, was replaced by resistant Klebsiella spp. and Pseudomonas spp. during nitrofurantoin. The carriage of these resistant organisms tripled during nitrofurantoin. Symptomatic infection dropped in half on nitrofurantoin, but this decline was due solely to infections caused by E. coli. Despite an increased frequency of resistant organisms on nitrofurantoin prophylaxis, an increase in urinary tract infections caused by these resistant organisms did not occur. CONCLUSION Routine use of nitrofurantoin prophylaxis in an attempt to eradicate bacteriuria in patients with chronic neurogenic bladder is not effective.

Explanation for false-positive urine cultures obtained by bag technique.

OBJECTIVE To test whether a urine bag technique, previously shown in circumcised male infants 1 month to 1 year of age to yield no false-positive cultures, would give similar results in newborns (females and circumcised and uncircumcised males). DESIGN Prospective study in which periurethral and urine specimens were obtained from healthy newborns. After the periurethral specimen was obtained, the perineum was washed and a urine bag applied. The urine bag was removed immediately after voiding and the urine was cultured. SETTING Normal newborn nursery and pediatric hospital. SUBJECTS Ninety-eight healthy full-term newborns (49 female and 49 male) admitted to the normal nursery during a 4-month period. MAIN RESULTS Isolation of a pathogen from the bag urine reflected periurethral flora. In 20 (95%) of the 21 urine specimens from which a pathogen was isolated, the same pathogen was detected on the periurethra. Sixteen of the 21 urine cultures were falsely positive (> 10(4) colony-forming units of pathogen per milliliter). In 50 (98%) of the 52 urine samples that yielded no growth, the periurethral culture was also negative. In the remaining 25 urine samples in which nonpathogens were detected, the periurethra yielded nonpathogens or no growth. Thus, if a pathogen was isolated from a bag urine sample, the same pathogen was detected on the periurethra 95% of the time. Conversely, if the bag urine sample was negative for a pathogen, the periurethral culture was negative 100% of the time. The presence of a pathogen on the periurethra was more common in female than male neonates (16 of 49 vs four of 49; P = .004), and none of the 14 circumcised male neonates had a pathogen detected on their periurethra or in their urine. CONCLUSION This study explains the finding of false-positive cultures with the bag technique. Pathogens detected in bag urine samples reflected pathogens on the periurethra. Until a bag collection technique that avoids contamination by periurethral flora can be developed, urethral catheterization and suprapubic aspiration remain the methods of choice for obtaining a urine specimen in female and uncircumcised male neonates.

Should we abandon standard microscopy when screening for urinary tract infections in young children

Dipstick analysis is a screening test for urinary tract infection (UTI) in office practice. Standard urine microscopy is available offsite. We evaluated the usefulness of these tests on consecutive urine samples obtained by bladder catheterization in young children with a possible UTI. Thirty of 230 children had positive cultures. Dipstick analysis was specific (98%) but not sensitive (70%). Standard microscopy was not specific. Dipstick analysis and urine culture are useful tests for the diagnosis of UTI.

Hospital-acquired infections in pediatric burn patients.

To determine the epidemiologic characteristics of hospital-acquired infections (HAI) in pediatric burn patients, we retrospectively reviewed hospital charts of pediatric burn patients from two similar burn units. All patients less than 18 years of age admitted to the burn unit from January 1, 1980 to July 10, 1988, were enrolled. Charts were analyzed for age, sex, burn injury (type, depth, burn surface area), and hospital course (burn wound therapy, use of indwelling catheters or tubes, infectious complications, antibiotic use, cause of death if patient died). Statistical analysis was done using a logistic regression model. Of the 224 children admitted, 32 (14%) had 58 infections during their stay in the burn unit. There was no significant difference in age, sex, race, burn type or use of wound excision between patients with or without infection. Patients who acquired an infection were more likely to have sustained a ≥20% full-thickness burn (14/32 vs 3/192 without infection), a smoke inhalation injury (10/32 vs 8/192), or have an indwelling device (29/32 vs 77/192). Thirteen (22%) of the 58 infections were burn wound infections due to Staphylococcus aureus or Pseudomonas aeruginosa, 12 (21%) were urinary tract infections due to Enterobacteriaceae, 11 (19%) were pneumonias caused by S aureus, Streptococcus pneumoniae or Pseudomonas sp, and 10 (17%) were bacteremias caused by S aureus or coagulase-negative staphylococci. The infection rate in pediatric patients hospitalized for burn injury in our study was significantly lower than the infection rate described for adult burn patients. As in adult patients, burn wound infections, pulmonary infections, and catheter-associated bacteremias are the most common infections in burned children. However, urinary tract infections are more frequent in the pediatric population. Risk factors (≥20% full-thickness burns, indwelling devices) and causative organisms are similar in both age groups.

Effect of periurethral colonization on the risk of urinary tract infection in healthy girls after their first urinary tract infection.

We examined whether periurethral colonization with bacterial pathogens predicts recurrent urimary tract infection (UTI) in girls at risk for infection. Periurethral and urine cultures were obtained weekly from each of seven healthy toilet-trained girls (3 to 6 years of age, normal urimary tract) during the 6 months after their first UTI, when the risk of UTI is 35%. Periurethral and urine isolates of Escherichia coli were grouped into electrophoretic types (ETs) by multilocus enzyme electrophoresis. Fifty-three (43%) of the 122 periurethral cultures were positive for a pathogen (median, 6 positive cultures/patient). Two patients each experienced 2 UTI. Positive periurethral cultures were as common in the five uninfected patients as in the two infected patients (9 of 32 vs. 44 of 90, P = 0.06). In only 1 of the 4 UTI was the infecting organism detected on the periurethra in the 2 weeks prior. Mutilocus enzyme electrophoresis of the 104 periurethral and urine E. coli isolates from the 7 patients revealed 22 ETs. Such a diversity of ETs suggests that the flora of the periurethral region is colonized by mul-

Expression of virulence factors among Escherichia coli isolated from the periurethra and urine of children with neurogenic bladder on intermittent catheterization.

BACKGROUND Patients with neurogenic bladder caused by spinal cord injury or myelomeningocele empty their bladder several times a day by intermittent catheterization. Bacteriuria without symptoms of infection is frequently present in these patients. Occasionally a clone of Escherichia coli that has been carried for weeks without symptoms causes a symptomatic urinary tract infection. Virulence factors are commonly expressed among E. coli causing infection in patients with normal urinary tracts. However, it is unknown whether expression of virulence factors by an E. coli clone colonizing the neurogenic bladder increases the risk of subsequent infection. In this study we examined the prevalence of virulence factor expression among E. coli isolated from the periurethra and urine of patients with neurogenic bladder. METHODS The prevalence of virulence factors was examined among E. coli isolated from the periurethra and urine in patients with neurogenic bladder who received intermittent catheterization and were followed for 6 months. Representative isolates from the 37 clonal types of E. coli detected in the periurethra and urine of children with neurogenic bladder were assessed for O antigen, hemolysin, aerobactin, serum resistance and type I and P-adhesin. RESULTS All clones were serum-resistant and expressed type I adhesin, none expressed aerobactin and two expressed hemolysin. The presence of P-adhesin was not unique to clones associated with symptomatic infection. The presence of P-adhesin carried for weeks in a clone did not predict subsequent infection in the neurogenic bladder. CONCLUSION Bacterial virulence factors did not predict infection of the neurogenic bladder.

Group A streptococcal pharyngitis in adults 30 to 65 years of age

BACKGROUND Although the frequency of group A streptococcal pharyngitis in adults is assumed to be low, there is little information on frequency other than in military populations. METHODS A prospective, observational study was done to determine the frequency of group A streptococcal pharyngitis in adults seen in the emergency department. Throat swabs were obtained on adults (30 to 65 years of age) with sore throat and pharyngitis on examination. Swabs were also obtained in a group of control subjects. RESULTS Of the 148 adults with pharyngitis, 65 (44%) had throat specimens positive for group A streptococci. In the 50 control subjects, all throat cultures were negative for group A streptococci. A significant number of patients with group A streptococcal pharyngitis had school-aged children at home. CONCLUSION The high rate of detection of group A streptococci in adults outside the military has not been previously reported.