Pediatric urinary tract infections

Urinary tract infections in children and adolescents with acute psychosis

OBJECTIVE

Schizophrenia is associated with increased infections. We previously found an association between urinary tract infection (UTI) and acute psychosis in adults. The aims of this study were to 1) evaluate the prevalence of UTI at the time of admission in children and adolescents with non-affective psychosis and psychotic depression versus those with non-psychotic major depressive disorder, and 2) compare demographic and clinical features between children and adolescents with acute psychosis with and without comorbid UTI.

METHOD

We performed a retrospective chart review of 227 subjects ages 10-18 who were hospitalized between 2005 and 2014 for an acute episode of DSM-IV non-affective psychosis (schizophrenia, schizoaffective disorder, psychosis NOS, or delusional disorder; n=80), major depressive disorder (MDD) with psychotic features (n=47); or MDD without psychotic features (n=100).

RESULTS

The prevalence of UTI was 20% in non-affective psychosis, 9% in MDD with psychotic features, and 13% in non-psychotic MDD. After controlling for potential confounders, UTI was 3.5 times more likely in subjects with non-affective psychosis than non-psychotic MDD (OR=3.5, 95% CI 1.3-9.2, p=0.01). Subjects with UTI had a higher prevalence of manic symptoms, but otherwise there were no associations between clinical characteristics and UTI in acute psychosis.

CONCLUSIONS

We found an association between UTIs and children and adolescents with acute non-affective psychosis. The results highlight the potential importance of screening for comorbid UTI in patients with acute psychosis.

Association Between Early Idiopathic Neonatal Jaundice and Urinary Tract Infections

Background and purpose:

Etiologic role, incidence, demographic, and response-to-treatment characteristics of urinary tract infection (UTI) among neonates, its relationship with significant neonatal hyperbilirubinemia, and abnormalities of the urinary system were studied in a prospective investigation in early (≤10 days) idiopathic neonatal jaundice in which all other etiologic factors of neonatal hyperbilirubinemia were ruled out.

Patients and methods:

Urine samples for microscopic and bacteriologic examination were obtained with bladder catheterization from 155 newborns with early neonatal jaundice. Newborns with a negative urine culture and with a positive urine culture were defined as group I and group II, respectively, and the 2 groups were compared with each other.

Results:

The incidence of UTI in whole of the study group was 16.7%. Serum total and direct bilirubin levels were statistically significantly higher in group II when compared with group I (P = .005 and P = .001, respectively). Decrease in serum total bilirubin level at the 24th hour of phototherapy was statistically significantly higher in group I compared with group II (P = .022).

Conclusions:

Urinary tract infection should be investigated in the etiologic evaluation of newborns with significant hyperbilirubinemia. The possibility of UTI should be considered in jaundiced newborns who do not respond to phototherapy well or have a prolonged duration of phototherapy treatment.

[Urinary tract infections in children]

Urinary tract infections (UTI) are the most common bacterial infections in children. The symptoms are not very specific and range from abdominal pain, poor feeding to nocturnal urinary incontinence. The technique of collecting urine plays an important role for securing the diagnosis. The best way to obtain urine in non-toilet-trained children is catheterization or suprapubic bladder aspiration. In toilet-trained children midstream urine is an acceptable alternative after cleaning the foreskin or labia. In the case of an infection a prompt empirical antibiotic therapy is necessary to reduce the risk of parenchymal scarring of the kidneys. There are different approaches to diagnose vesicoureteral reflux in different countries. The commonly used standard approach in Germany is voiding cystourethrography. In the case of reflux dimercaptosuccinic acid (DMSA) scintigraphy should be performed additionally to exclude renal scarring (bottom-up approach).

Sex differences in child and adolescent physical morbidity: cohort study

BACKGROUND

Evidence on sex differences in physical morbidity in childhood and adolescence is based largely on studies employing single/few physical morbidity measures and different informants. We describe sex differences in a wide range of parent/carer-reported physical morbidity measures between ages 4 and 13 years to determine evidence for a generalised pattern of an emerging/increasing female 'excess'.

METHODS

Parents/carers (approximately 90% mothers) of the population-based UK ALSPAC cohort provided data on general health, physical conditions/symptoms and infections in their child approximately annually between ages 4 and 13. Logistic regression analyses determined the odds of each morbidity measure being reported in respect of females (vs males) at each age and the sex-by-age interaction, to investigate any changing sex difference with age.

RESULTS

Six measures (general health past year/month, high temperature, rash, eye and ear infections) demonstrated an emerging female 'excess', and six (earache, stomach-ache, headache, lice/scabies, cold sores, urinary infections) an increasing female 'excess'; one (breathlessness) showed a disappearing male 'excess'. Just two showed either an emerging or increasing male 'excess'. Most changes were evident during childhood (prepuberty). Six measures showed consistent female 'excesses' and four consistent male 'excesses'. Few measures showed no sex differences throughout this period of childhood/early adolescence.

CONCLUSION

Sex differences are evident for a wide range of parent-reported physical morbidity measures in childhood and early adolescence. Far more measures showed an emerging/increasing female 'excess' than an emerging/increasing male 'excess'. Further studies are required to examine whether patterns differ across sociodemographic/cultural groups, and to explain this generalised pattern.

Paediatric Urinary Tract Infection: A Hospital Based Experience

INTRODUCTION

Paediatric Urinary Tract Infection (UTI) is one of the commonly encountered entities by paediatricians. Studies have shown easy vulnerability of paediatric urinary tract in any acute febrile illness and a miss in diagnosis could have long term consequences like renal scaring with its adverse effects. Bearing these evidence based preludes in view we designed our study to know the prevalence of UTI in Kashmir province.

AIM

Aim of the present study was to know the prevalence of UTI in febrile children and to know the sensitivity of different imaging modalities like Renal and Urinary Bladder Ultrasonography (RUS), Voiding Cystourethrography (VCUG) and Dimercaptosuccinic Acid (DMSA) scan in diagnosing UTI.

MATERIALS AND METHODS

A total of 304 patients, between 2 months to 10 years, with axillary temperature of ≥ 100.4^oF (38^oC), who did not have a definite source for their fever and who were not on antibiotics were included in the study. Detailed history and through clinical examination was done to rule out any potential or definite focus of infection as per the predesigned proforma. Routine urine examination with culture and sensitivity, followed by RUS and VCUG was done in all patients where routine urine examination was suggestive of UTI. DMSA was done in only culture proven cases after 6 months to document the renal scarring.

RESULTS

Out of 304 children, 140 were males and 164 were females, UTI was present in 40 patients who had fever without any apparent cause giving a prevalence of 13.2%. Escherichia coli (E. coli) were the commonest isolated organism, followed by Klebsiella and Citrobacter species. Renal and Urinary Bladder Ultrasonography (RUS) detected Vesicoureteral Reflux (VUR) in 25% (10/40) while VCUG showed VUR in 55% (22/40) giving a RUS sensitivity of 45% for detecting VUR. DMSA done only after 6 months in UTI diagnosed patients showed a renal scarring in 25% (10/40) patients.

CONCLUSION

Missing a febrile paediatric UTI, can prove a future catastrophe if not timely diagnosed and treated.

The prevalence of urinary tract infection in children with severe acute malnutrition: a narrative review

This article aims to review the current evidence which shows that the prevalence of urinary tract infection (UTI) has been increasing in children with severe acute malnutrition (SAM). UTI remains one of the most common causes of febrile illness in pediatric practice. Most studies conducted among hospitalized children with complicated SAM have reported high prevalence rates of UTI. Clearly, the knowledge of baseline risk of UTI can help clinicians to make informed diagnostic and therapeutic decisions in these children. From the global reports reviewed in this article, UTI prevalence rates range from as low as 6% to as high as 37% in developing countries, while the most common bacterial isolates from urine cultures are Gram-negative coliform organisms such as Escherichia coli and Klebsiella species. These findings form the basis for the current diagnostic and therapeutic guidelines for clinicians managing children with complicated SAM. With the reported high prevalence of UTI among these children and concerns over antibiotic resistance, more extensive data are required using standardized microbiological methods. Thus, the assessment of the performance of urine dipsticks and microscopy against the gold standard urine culture is an important step toward strengthening the evidence for the therapeutic guidelines for UTI in children with SAM.

Assessment of the effectiveness of three different cephalosporin/clavulanate combinations for the phenotypic confirmation of extended-spectrum beta-lactamase producing bacteria isolated from urine samples at National Public Health Laboratory, Kathmandu, Nepal

Background

The extended-spectrum β-lactamase (ESBL) producing bacteria are present as the serious public health problems due to their resistance to large number of antibiotics. The main aims of this study were to determine the prevalence and antibiotic resistance patterns of bacteria producing extended-spectrum β-lactamases (ESBLs) and to find the suitable cephalosporin/clavulanate combination for phenotypic confirmation of ESBL production.

Methods

During the study period from April 2013 to November 2013, a total of 1003 urine samples from the patients visiting National Public Health Laboratory, Kathmandu, Nepal were collected and processed. The isolates were identified with the help of colony characteristics, gram stain and conventional biochemical tests. Antimicrobial susceptibility testing was performed by Kirby Bauer disc diffusion method. ESBL production screening was done by using ceftriaxone, while ESBL production confirmation was done by using three different 3rd generation cephalosporin/clavulanate combinations.

Results

Of the 138 isolates, Escherichia coli was the most predominant with 88 (63.8 %) isolates. Among the antibiotics tested for gram negative bacteria, highest susceptibility was seen toward imipenem followed by amikacin. Of the total isolates, 68 (49.3 %) were suspected as ESBL producers. Of these, 44 (64.7 %) were phenotypically confirmed to be ESBL producers. The majority of ESBL producers were E. coli with 34 (72.3 %) isolates. Of the three different 3rd generation cephalosporin/clavulanate combinations used, ceftazidime/clavulanate combination was found to be most effective for phenotypic confirmation of ESBL producers and was statistically highly significant (P < 0.01).

Conclusion

Based on the findings of our study, we recommend to use ceftazidime/clavulanate combination for phenotypic confirmation of ESBL producers. Routine ESBL testing for uropathogens along with conventional antibiogram would be useful for proper early management of all the cases of urinary tract infections.

Bacterial Uropathogens Causing Urinary Tract Infection and Their Resistance Patterns Among Children in Turkey

Background

Urinary tract infection (UTI) is a common problem in infants and children, as well as adults.

Objectives

The aim of this study was to assess the most common bacterial uropathogens, their susceptibility, and resistance to antibiotics in children with UTI.

Materials and Methods

This study included 7,365 urine samples sent from various departments to the Kars state hospital microbiology laboratory between January 2012 and May 2014. Bacterial isolation from clinical samples was made using standard microbiological methods. Antibiotic susceptibilities were determined by disk diffusion, according to CLSI recommendations.

Results

Bacterial growth was obtained in 1,373 samples (18.5%). The percentage distributions of the isolates were as follows: Escherichia coli, 940 (68.5%); Proteus spp, 183 (13.3%); Staphylococcus spp, 85 (6.2%); Enterococcus spp, 65 (4.7%); Klebsiella, 62 (4.5%); Pseudomonas aeruginosa, 21 (1.5%); and other Gram-negative bacteria and Gram-positive bacteria, 17 (1.2%). UTIs were more prevalent, after two years of age, among females than males (P < 0.001).

Conclusions

The identification of the most common microorganisms causing infectious diseases and regional resistance patterns is important in order to determine the antimicrobial policies and infection control guidelines of hospitals.

Evaluation of the Bladder Stimulation Technique to Collect Midstream Urine in Infants in a Pediatric Emergency Department

OBJECTIVE

Midstream clean-catch urine is an accepted method to diagnose urinary tract infection but is impracticable in infants before potty training. We tested the bladder stimulation technique to obtain a clean-catch urine sample in infants.

MATERIALS AND METHODS

We included 142 infants under walking age who required a urine sample in a cross-sectional study carried out during a 3-months period, from September to November 2014, in the emergency department of the University Children's Hospital of Nice (France). A technique based on bladder stimulation and lumbar stimulation maneuvers, with at least two attempts, was tested by four trained physicians. The success rate and time to obtain urine sample within 3 minutes were evaluated. Discomfort (EVENDOL score ≥4/15) was measured. We estimated the risk factors in the failure of the technique. Chi-square test or Fisher's exact test were used to compare frequencies. T-test and Wilcoxon test were used to compare quantitative data according to the normality of the distribution. Risk factors for failure of the technique were evaluated using a multivariate logistic regression model.

RESULTS

We obtained midstream clean-catch urine in 55.6% of infants with a median time of 52.0 s (10.0; 110.0). The success rate decreased with age from 88.9% (newborn) to 28.6% (>1 y) (p = 0.0001) and with weight, from 85.7% (<4 kg) to 28.6% (>10 kg) (p = 0.0004). The success rate was 60.8% for infants without discomfort (p<0.0001). Heavy weight and discomfort were associated with failure, with adjusted ORs of 1.47 [1.04-2.31] and 6.65 [2.85-15.54], respectively.

CONCLUSION

Bladder stimulation seems to be efficient in obtaining midstream urine with a moderate success rate in our study sample. This could be an alternative technique for infants before potty training but further randomized multicenter studies are needed to validate this procedure.

Serotyping and Antimicrobial Susceptibility Pattern of Escherichia coli Isolates from Urinary Tract Infections in Pediatric Population in a Tertiary Care Hospital

Urinary tract infections (UTIs) in pediatric population are associated with high morbidity and long term complications. In recent years, there is increased prevalence of Escherichia coli (E. coli) strains producing extended spectrum β-lactamase, Amp C, and Metallo β-lactamase, making the clinical management even more difficult. This study was aimed to detect the serotypes and to determine antimicrobial susceptibility profile of E. coli isolates from urine samples of children <10 yrs old. A total of 75 pure E. coli strains isolated from patients with symptoms of UTI and colony count ≥10⁵ organisms/mL were included in the study. Antibiotic sensitivity pattern showed maximum resistance to nalidixic acid (98.7%), followed by ampicillin (97.3%), amoxi-clavulanate (96%), and fluoroquinolones (92%) while most of the isolates were found sensitive to piperacillin-tazobactam (13.3%), nitrofurantoin (5.3%), and meropenem (1.3%). 48% of the strains were ESBL producer (extended spectrum beta lactamase). 44% strains were typable withantisera used in our study and the most common serogroup was O6 (33.3%) followed by O1 (15.1%) and O15 (15.1%). To conclude, judicious use of antibiotics according to hospital antibiotic policy and infection control measures should be implemented to prevent spread of multidrug resistant organisms.

Deep Venous Thrombosis in Teen With Crouzon Syndrome Post-Le Fort III Osteotomy With Rigid External Distraction

Venous thromboembolic events are rare in pediatric patients. Risk factors associated with the development of venous thromboembolic events in pediatric patients include the use of central venous catheters, hospitalization, cancer, sepsis, trauma, surgery, and congenital prothrombotic disorders.The authors present the case of a 14-year-old man with Crouzon syndrome who required Le Fort III osteotomy with rigid external distraction for significant midface hypoplasia who presented postoperatively with an extensive deep venous thrombosis. This is the first reported case of symptomatic venous thrombosis post-Le Fort III osteotomy and rigid external distraction. Although rare, surgeons should be aware of this potential complication.

Study on Bacterial Strains Causing Blood and Urinary Tract Infections in the Neonatal Intensive Care Unit and Determination of Their Antibiotic Resistance Pattern

BACKGROUND

Infections are considered as one of the main factors of neonatal mortality, especially in developing countries. Blood and urine infections are one of the most prevalent infectious factors among the infants. On the other hand, resistance against antimicrobial factors is one of the major problems in the world, and it is important to be informed about antibiotic resistance pattern of microorganisms for treatment of infections.

OBJECTIVES

The aim of this study was to examine the bacterial strains causing blood and urinary tract infections in Neonatal Intensive Care Unit (NICU) and determine their antibiotic resistance pattern.

MATERIALS AND METHODS

In this study, the microorganisms of 150 blood and urine samples of infants hospitalized in NICUs of Imam Hussein Hospital, Children Hospital Center and Bahrami Hospital in Tehran, Iran, were collected during seven months, and the antimicrobial resistance patterns of the isolates were studied by the Kirby-Bauer test.

RESULTS

During the seven-month study on 105 samples, including 85 (81%) urine samples and 20 (19%) blood samples, 81 samples (77.1%) were Gram-negative and 24 (22.9%) were Gram-positive organisms. Klebsiella pneumoniae (30.5%) was the most common Gram-negative microorganisms and Staphylococcus epidermidis (11.4%) was the most prevalent Gram-positive microorganisms. The most antimicrobial susceptibility in Gram-negative microorganisms was shown to ciprofloxacin (84.2%) and in Gram- positive ones was shown to vancomycin (83.3%).

CONCLUSIONS

This results of the study show that the most contamination in NICUs is from Gram-negative bacteria and ciprofloxacin is the most effective antibiotic for treatment. Thus, the control of infections in NICUs in hospitals is very important.

Midstream clean-catch urine collection in newborns: a randomized controlled study

We aimed to evaluate a recently defined technique based on bladder stimulation and paravertebral lumbar massage maneuvers in collecting a midstream clean-catch urine sample in newborns. A total of 127 term newborns were randomly assigned either to the experimental group or the control group. Twenty-five minutes after feeding, the genital and perineal areas of the babies were cleaned. The babies were held under the armpits with legs dangling. Bladder stimulation and lumbar paravertebral massage maneuvers were only applied to the babies in the experimental group. Success was defined as collection of a urine sample within 5 min of starting the stimulation maneuvers in the experimental group and of holding under the armpits in the control group. The success rate of urine collection was significantly higher in the experimental group (78%) than in the control group (33%; p < 0.001). The median time (interquartile range) for sample collection was 60 s (64.5 s) in the experimental group and 300 s (95 s) in the control group (p < 0.0001). Contamination rates were similar in both groups (p = 0.770).

CONCLUSION

We suggest that bladder stimulation and lumbar paravertebral massage is a safe, quick, and effective way of collecting midstream clean-catch urine in newborns.

Community-acquired urinary tract infection in hospitalized children: etiology and antimicrobial resistance. A comparison between first episode and recurrent infection

Urinary tract infection (UTI) is common in infants and children, and Escherichia coli is the leading pathogen. The aims of this study were to compare first episode of UTI with recurrent infection, reveal organisms that cause UTI, uropathogen resistance, and presence of bacteria producing extended-spectrum β-lactamase (ESBL). The first-UTI group included 456 children. E coli was the leading pathogen (80.5%), and Pseudomonas aeruginosa was found in 1.5%. The uropathogens were resistant to gentamicin (3.41%) and cefuroxime (5.71%), and highly resistant to cefamezin (37.39%). The recurrent-infection group included 106 children. E coli was also the leading pathogen, but 7.5% of the isolates were P aeruginosa (P = .002 compared with first-episode group); 6.6% were ESBL-producing bacteria compared with 1.1% in the first-episode group (P = .002). E coli is the leading pathogen in both groups. P aeruginosa and ESBL-producing bacteria were more common in the recurrent infection group.

Evaluation and management of recurrent urinary tract infections in children: state of the art

Urinary tract infections (UTIs) represent an important cause of febrile illness in young children and can lead to renal scarring and kidney failure. However, diagnosis and treatment of recurrent UTI in children is an area of some controversy. Guidelines from the American Academy of Pediatrics, National Institute for Health and Clinical Excellence and European Society of Paediatric Radiology differ from each other in terms of the diagnostic algorithm to be followed. Treatment of vesicoureteral reflux and antibiotic prophylaxis for prevention of recurrent UTI are also areas of considerable debate. In this review, we collate and appraise recently published literature in order to formulate evidence-based guidance for the diagnosis and treatment of recurrent UTI in children.

The diagnosis, evaluation and treatment of acute and recurrent pediatric urinary tract infections

Urinary tract infection (UTI) is one of the most common bacterial infections encountered by pediatricians. Currently, the diagnosis and management of acute UTI and recurrent UTI in children remain controversial. Recently published guidelines and large clinical trials have attempted to clarify UTI diagnostic and management strategies. In this manuscript, we review the diagnosis and management of acute and recurrent UTI in the pediatric population.

Synthesis of the pentasaccharide repeating unit of the O-antigen of E. coli O117:K98:H4

The pentasaccharide repeating unit of the O-antigen of E. coli O117:K98:H4 strain has been synthesized using a combination of sequential glycosylations and [3 + 2] block synthetic strategy from the suitably protected monosaccharide intermediates. Thioglycosides and glycosyl trichloroacetimidate derivatives have been used as glycosyl donors in the glycosylations.

[Antimicrobial susceptibility of uropathogens from uncomplicated urinary tract infection in a pediatric hospital]

BACKGROUND

Urinary tract infection in children is well recognized as a cause of acute morbidity and chronic medical conditions. As a result, appropriate use of antimicrobial agents, however, increases antibiotic resistance and complicates its treatment due to increased patient morbidity, costs, rates of hospitalization, and use of broader-spectrum antibiotics. The goal of this study was to determine antibiotic susceptibility to commonly used agents for urinary tract infection against recent urinary isolates.

METHODS

A total of 457 consecutive children attending the emergency room at the Hospital Infantil de México Federico Gómez with symptoms of uncomplicated lower urinary tract infection were eligible for inclusion. Patients who had had symptoms for≥7 days and those who had had previous episodes of urinary tract infection, received antibiotics or other complicated factors were excluded. Midstream and catheter urine specimens were collected. All isolates were identified and the in vitro activities of antimicrobials were determined.

RESULTS

The most frequently isolated urinary pathogens were as follows: Escherichia coli (E. coli) (312, 68.3%), Enterococcus spp. (42, 11%), Klebsiella pneumoniae (K. pneumoniae) (40, 8.7%), Pseudomonas aeruginosa (P. aeruginosa) (34, 7.5%), Proteus mirabilis (P. mirabilis) (21, 4.5%), Enterobacter cloacae (8, 1.7%). The resistance to trimetoprim/sulfametoxazol (%) was 73.7, 62.2, 100, 52, and 50, respectively, for E. coli, K. pneumoniae, P. aeruginosa, P. mirabilis and Enterobacter spp., 92.5 for Enterococcus faecalis (E. faecalis) and 49.9 for Enterococcus faecium (E. faecium). Ampicillin was 86.3, 45, 100, 47.9, and 66.6% for the same strains, ciprofloxacin 33.8, 9, 18.8, 0, 0%, nitrofurantoin 4.4, 13, 97.7, 70, 0%; to E. faecalis 0% and 16.7% to E. faecium.

CONCLUSIONS

Frequently prescribed empirical agents for uncomplicated urinary tract infection demonstrate lowered in vitro susceptibilities when tested against recent clinical isolates.

Effect of ceftriaxone on the outcome of murine pyelonephritis caused by extended-spectrum-β-lactamase-producing Escherichia coli

Urinary tract infections (UTIs) due to extended-spectrum-β-lactamase (ESBL)-producing Enterobacteriaceae in children are becoming more frequent, and they are commonly treated initially with a second- or third-generation cephalosporin. We developed a murine model of ascending UTI caused by ESBL-producing Escherichia coli. Using this model, we investigated the renal bacterial burden, interleukin-6 (IL-6) expression, and histopathological alterations caused by ESBL- and non-ESBL-producing bacteria after 1, 2, or 6 days with or without ceftriaxone therapy. The renal bacterial burden, IL-6 concentration, and histological inflammatory lesions were not significantly different between mice infected with ESBL- and non-ESBL-producing bacteria without treatment at any of the time points examined. Following ceftriaxone administration, the bacterial burden was eliminated in the kidneys of mice infected with ESBL- and non-ESBL-producing bacteria on the 6th postinfection day. The histological analysis demonstrated that among mice treated with ceftriaxone, those infected with ESBL-producing bacteria had more profound renal alterations than those infected with non-ESBL-producing bacteria on the 6th day (P < 0.001). In comparison, microbiological outcomes did not differ significantly between mice infected with ESBL- and non-ESBL-producing bacteria at any of the time points examined. The effectiveness of ceftriaxone in mice with UTIs due to ESBL-producing E. coli may have therapeutic implications; it is, however, hampered by limited activity on the histopathological lesions, a finding that needs further investigation.

Clinical options for the treatment of urinary tract infections in children

Urinary Tract Infections (UTI) are a common cause of childhood febrile illness with 7% of girls and 2% of boys having a symptomatic culture positive UTI by the age of six years. Although there are conflicting views on the long term sequelae of UTI, as well as the place of prophylaxis, the universal aims of treatment of childhood UTI remain those of symptom alleviation, prevention of systemic infection and short and longer term complications. There is good evidence of historical and emerging resistance patterns, therefore rationalisation of prescription patterns by knowledge of sensitivities coupled with re-examination of empirical antibiotic choices is clearly important. Local formularies should reflect geographical resistance patterns along with best evidence on the duration and choice of antibiotic in order to maximize therapeutic effect, while minimizing the development of resistant strains.

Robustness and plasticity of metabolic pathway flux among uropathogenic isolates of Pseudomonas aeruginosa

Pseudomonas aeruginosa is a human pathogen that frequently causes urinary tract and catheter-associated urinary tract infections. Here, using ¹³C-metabolic flux analysis, we conducted quantitative analysis of metabolic fluxes in the model strain P. aeruginosa PAO1 and 17 clinical isolates. All P. aeruginosa strains catabolized glucose through the Entner-Doudoroff pathway with fully respiratory metabolism and no overflow. Together with other NADPH supplying reactions, this high-flux pathway provided by far more NADPH than needed for anabolism: a benefit for the pathogen to counteract oxidative stress imposed by the host. P. aeruginosa recruited the pentose phosphate pathway exclusively for biosynthesis. In contrast to glycolytic metabolism, which was conserved among all isolates, the flux through pyruvate metabolism, the tricarboxylic acid cycle, and the glyoxylate shunt was highly variable, likely caused by adaptive processes in individual strains during infection. This aspect of metabolism was niche-specific with respect to the corresponding flux because strains isolated from the urinary tract clustered separately from those originating from catheter-associated infections. Interestingly, most glucose-grown strains exhibited significant flux through the glyoxylate shunt. Projection into the theoretical flux space, which was computed using elementary flux-mode analysis, indicated that P. aeruginosa metabolism is optimized for efficient growth and exhibits significant potential for increasing NADPH supply to drive oxidative stress response.

Variation in antibiotic susceptibility of uropathogens by age among ambulatory pediatric patients

We compared uropathogen antibiotic susceptibility across age groups of ambulatory pediatric patients. For Escherichia coli (n=5,099) and other Gram-negative rods (n=626), significant differences (p<0.05) existed across age groups for ampicillin, cefazolin, and trimethoprim/sulfamethoxazole susceptibility. In E. coli, differences in trimethoprim/sulfamethoxazole susceptibility varied from 79% in children under 2 to 88% in ages 16-18 (p<0.001), while ampicillin susceptibility varied from 30% in children under 2 to 53% in ages 2-5 (p=0.015). Uropathogen susceptibility to common urinary anti-infectives may be lower in the youngest children. Further investigation into these differences is needed to facilitate appropriate and prudent treatment of urinary tract infections.

In Vitro Antibiofilm Efficacies of Different Antibiotic Combinations with Zinc Sulfate against Pseudomonas aeruginosa Recovered from Hospitalized Patients with Urinary Tract Infection

Urinary tract infections (UTIs) are a serious healthcare dilemma influencing millions of patients every year and represent the second most frequent type of body infection. Pseudomonas aeruginosa is a multidrug-resistant pathogen causing numerous chronic biofilm-associated infections including urinary tract, nosocomial, and medical devices-related infections. In the present study, the biofilm of P. aeruginosa CCIN34519, recovered from inpatients with UTIs, was established on polystyrene substratum and scanning electron microscopy (SEM) and was utilized for visualization of the biofilm. A previously described in vitro system for real-time monitoring of biofilm growth/inhibition was utilized to assess the antimicrobial effects of ciprofloxacin, levofloxacin, moxifloxacin, norfloxacin, ertapenem, ceftriaxone, gentamicin, and tobramycin as single antibiotics as well as in combinations with zinc sulfate (2.5 mM) against P.aeruginosa CCIN34519 biofilm. Meanwhile, minimum inhibitory concentrations (MICs) at 24 h and mutant prevention concentrations (MPCs) at 96 h were determined for the aforementioned antibiotics. The real-time monitoring data revealed diverse responses of P.aeruginosa CCIN34519 biofilm to the tested antibiotic-zinc sulfate combinations with potential synergisms in cases of fluoroquinolones (ciprofloxacin, levofloxacin, moxifloxacin, and norfloxacin) and carbapenem (ertapenem) as demonstrated by reduced MIC and MPC values. Conversely, considerable antagonisms were observed with cephalosporin (ceftriaxone) and aminoglycosides (gentamicin, and tobramycin) as shown by substantially increased MICs and MPCs values. Further deliberate in vivo investigations for the promising synergisms are required to evaluate their therapeutic potentials for treatment of UTIs caused by P. aeruginosa biofilms as well as for developing preventive strategies.

Nonionizing photoacoustic cystography with near-infrared absorbing gold nanostructures as optical-opaque tracers

AIM

The objectives of this study were to demonstrate nonionizing photoacoustic tomography (PAT) of bladders with near-infrared absorbing gold nanocages (GNCs) as an optical-turbid tracer and to investigate the fate of GNCs after photoacoustic imaging.

MATERIALS & METHODS

The rats' bladders were visualized using PAT after transurethral injection of 2-nM GNCs. The fate of GNCs in the bladders was investigated. Spectroscopic PAT was applied to identify GNC-filled bladders in vivo and study biodistribution ex vivo.

RESULTS

Rats' bladders filled with GNCs were successfully imaged using a PAT system. The photoacoustic amplitude was enhanced by approximately 2240%. Both in vivo and ex vivo PAT results reveal that no accumulation of GNCs in the bladder and kidney was observed, and were validated with inductively coupled plasma mass spectrometry.

CONCLUSION

The PAT with transurethral injection of GNCs provides two crucial safety features for clinical translation: no radiation exposure and no long-term heavy metal accumulation.

Urinary infections in children

Urinary tract infection (UTI) is a common infection in infants and children. During infancy, boys are more commonly affected than girls and thereafter, female preponderance is found. Presentation varies among different age groups. Clinical features in neonates and young infants are non-specific, manifest as septicemia where a high index of suspicion is needed. Older children typically present as simple or complicated UTI. Rapid diagnosis, institution of early treatment and further evaluation by imaging modalities are of utmost importance. The prevention of recurrent UTI and detection of congenital anomalies of kidney and urinary tract are major objectives in the management. Use of ultrasound is required to detect underlying congenital abnormalities, whereas voiding cystourethrogram and dimercaptosuccinic acid (DMSA) scan are useful in the diagnosis of obstructive uropathy and vesicoureteric reflux and renal scar, respectively. The children requiring surgical interventions are to be recognised early to prevent recurrent UTI. The treatment of vesicoureteric reflux by chemoprophylaxis in lower grades and surgical treatment in higher grades are important consideration in prevention of recurrent UTI. This is required to prevent renal parenchymal damage and scarring that can cause hypertension and progressive renal insufficiency in later life.

Photoacoustic cystography

Conventional pediatric cystography, which is based on diagnostic X-ray using a radio-opaque dye, suffers from the use of harmful ionizing radiation. The risk of bladder cancers in children due to radiation exposure is more significant than many other cancers. Here we demonstrate the feasibility of nonionizing and noninvasive photoacoustic (PA) imaging of urinary bladders, referred to as photoacoustic cystography (PAC), using near-infrared (NIR) optical absorbents (i.e. methylene blue, plasmonic gold nanostructures, or single walled carbon nanotubes) as an optical-turbid tracer. We have successfully imaged a rat bladder filled with the optical absorbing agents using a dark-field confocal PAC system. After transurethral injection of the contrast agents, the rat's bladders were photoacoustically visualized by achieving significant PA signal enhancement. The accumulation was validated by spectroscopic PA imaging. Further, by using only a laser pulse energy of less than 1 mJ/cm(2) (1/20 of the safety limit), our current imaging system could map the methylene-blue-filled-rat-bladder at the depth of beyond 1 cm in biological tissues in vivo. Both in vivo and ex vivo PA imaging results validate that the contrast agents were naturally excreted via urination. Thus, there is no concern regarding long-term toxic agent accumulation, which will facilitate clinical translation.

Highlights for management of a child with a urinary tract infection

Urinary tract infections remain the most common bacterial infection in childhood. Escherichia coli is responsible for over 80% of Pediatric UTIs. Other common gram negative organisms include Kleibsiella, Proteus, Enterobacter and occasionally Pseudomonas. Signs and symptoms vary greatly by age of the patient becoming more specific as the child grows older. Even in the absence of specific signs a UTI should be included in the differential diagnosis of high grade fever. In younger children, presence of upper respiratory infections, otitis media or gastroenteritis does not eliminate the possibility of a UTI. Culture of the urine remains the gold standard for diagnosing UTIs. All males and females with well documented UTIs should be imaged for the presence of urological anomalies associated with UTI. Depending on patient's clinical symptoms and tolerance, therapy can be oral or parenteral as they have both been found equally efficacious. Healthcare professionals should ensure that when a child or young person has been identified as having a suspected UTI, they and their parents are given information about the need for treatment, the importance of completing any course of treatment and advice about prevention and possible long-term management.

Synthesis of the tetrasaccharide motif and its structural analog corresponding to the lipopolysaccharide of Escherichia coli O75

Background

Extraintestinal pathogenic E. coli are mostly responsible for a diverse spectrum of invasive human and animal infections leading to the urinary tract infections. Bacterial lipopolysaccharides are responsible for their pathogenicity and their interactions with host immune responses. In spite of several breakthroughs in the development of therapeutics to combat urinary tract infections and related diseases, the emergence of multidrug-resistant bacterial strains is a serious concern. Lipopolysaccharides are attractive targets for the development of long-term therapeutic agents to eradicate the infections. Since the natural sources cannot provide the required amount of oligosaccharides, development of chemical synthetic strategies for their synthesis is relevant to gain access to a reservoir of oligosaccharides and their close analogs.

Methodology

Two tetrasaccharide derivatives were synthesized from a single disaccharide intermediate. β-d-mannoside moiety was prepared from β-d-glucoside moiety following oxidation–reduction methodology. A [2+2] stereoselective block glycosylation strategy has been adopted for the preparation of tetrasaccharide derivative. α-d-Glucosamine moiety was prepared from α-d-mannosidic moiety following triflate formation at C-2 and S_N² substitution. A one-pot iterative glycosylation exploiting the orthogonal property of thioglycoside was carried out during the synthesis of tetrasaccharide analog.

Results

Synthesis of the tetrasaccharide motif (1) and its structural analog (2) corresponding to the lipopolysaccharide of Escherichia coli O75 was successfully achieved in excellent yield. Most of the reactions are clean and high yielding. Both compounds 1 and 2 were synthesized as their 4-methoxyphenyl glycoside, which can act as a temporary anomeric protecting group for further use of these tetrasaccharides in the preparation of glycoconjugates.

Association of malodorous urine with urinary tract infection in children aged 1 to 36 months

OBJECTIVE

To determine whether parental reporting of malodorous urine is associated with urinary tract infection (UTI) in children.

METHODS

We conducted a prospective consecutive cohort study in the emergency department of a pediatric hospital from July 31, 2009 to April 30, 2011. All children aged between 1 and 36 months for whom a urine culture was prescribed for suspected UTI (ie, unexplained fever, irritability, or vomiting) were assessed for eligibility. A standardized questionnaire was administered to the parents by a research assistant. The primary outcome measure was a UTI.

RESULTS

Three hundred ninety-six children were initially enrolled, but 65 were excluded a posteriori either because a urine culture, although prescribed, was not done (11), was collected by bag (39), and/or showed gross contamination (25). Therefore, 331 children were included in the final analysis. Their median age was 12 months (range, 1-36). Criteria for UTI were fulfilled in 51 (15%). A malodorous urine was reported by parents in 57% of children with UTI and in 32% of children without UTI. On logistic regression, malodorous urine was associated with UTI (odds ratio 2.83, 95% confidence interval: 1.54-5.20). This association remained statistically significant when adjusted for gender and the presence of vesicoureteral reflux (odds ratio 2.73, 95% confidence interval: 1.46-5.08).

CONCLUSIONS

Parental reporting of malodorous urine increases the probability of UTI among young children being evaluated for suspected UTI. However, this association is not strong enough to definitely rule in or out a diagnosis of UTI.

Use of urine dipstick evaluating young infants with fever without a source and positive urine culture

We analyzed 239 febrile infants <3 months of age with a positive urine culture to examine their characteristics. Patients with altered urine dipstick showed more commonly alterations of the biologic markers for bacterial infection, and Escherichia coli was more commonly isolated. Febrile young infants with positive urine culture and negative urine dipstick may not have a urinary tract infection and less aggressive management can be considered.

Pediatric urinary tract infections

Urinary tract infections (UTIs) in children are commonly seen in the emergency department and pose several challenges to establishing the proper diagnosis and determining management. This article reviews pediatric UTI and addresses epidemiology, diagnosis, treatment, and imaging, and their importance to the practicing emergency medicine provider. Accurate and timely diagnosis of pediatric UTI can prevent short-term complications, such as severe pyelonephritis or sepsis, and long-term sequelae including scarring of the kidneys, hypertension, and ultimately chronic renal insufficiency and need for transplant.

Streptococcus pneumoniae in urinary tracts of children with chronic kidney disease

Streptococcus pneumoniae is not commonly considered an agent of urinary tract infections. We report 3 children with urinary tract abnormalities who had high numbers of S. pneumoniae in their urine (>10⁴ CFU/mL) and varying clinical symptoms.

Antimicrobial resistance among Escherichia coli that cause childhood community-acquired urinary tract infections in Northern Italy

BACKGROUND

Resistance rate of Escherichia coli against antimicrobials that are commonly prescribed in pediatric urinary tract infections is currently a matter of concern.

METHODS

The antimicrobial susceptibility patterns of uropathogenic Escherichia coli strains to the common antibimcrobials ampicillin, cotrimoxazole, coamoxyclav, ceftazidime, ceftriaxone, nitrofurantoin, and gentamycin were determined in 177 children aged from 2 to 36 months. They presented with their first symptomatic community acquired urinary tract infection at the Department of Pediatrics, San Leopoldo Mandic Hospital, Merate-Lecco.

RESULTS

High rates of ampicillin (inpatients: 50%; outpatients: 52%) resistance were identified. The resistance for cotrimoxazole (inpatients: 22%; outpatients: 15%) and especially coamoxyclav (inpatients: 6%; outpatients: 10%) was less pronounced than that to ampicillin. No resistance or less than 1% of resistance was identified for ceftazidime, ceftriaxone, nitrofurantoin, and gentamycin both in inpatients and in outpatients.

CONCLUSIONS

Italian children affected with a community acquired urinary tract infection are initially managed orally with coamoxyclav or parenterally with ceftriaxone. The results of the present retrospective analysis support this attitude. Parenteral ceftriaxone or an aminoglycoside should be considered for patients on antimicrobial prophylaxis or recently prescribed antimicrobials.

Infecção urinária em menores de 15 anos: etiologia e perfil de sensibilidade antimicrobiana em hospital geral de pediatria

OBJETIVO: Descrever a prevalência dos principais agentes etiológicos de infecção urinária comunitária em crianças menores de 15 anos e analisar o perfil de sensibilidade antimicrobiana do principal agente, Escherichia coli. MÉTODOS: Estudo retrospectivo conduzido a partir de uroculturas com crescimento de agente único, com unidades formadoras de colônia maior ou igual a 10(5)/mL. A população selecionada foi atendida no Pronto Atendimento de Pediatria do Hospital Universitário da Universidade de São Paulo entre janeiro de 2006 e dezembro de 2007. Para analisar o perfil de sensibilidade de E. coli, foram excluídos casos com infecção urinária de repetição e/ou portadores de uropatias. RESULTADOS: Dos 176 casos de infecção urinária, 133 (76%) ocorreram no sexo feminino e 43 (24%) no masculino. A faixa etária de maior prevalência das infecções urinárias foi a de menores de dois anos, com 84 casos (48%). Escherichia coli foi o principal agente isolado (122 culturas - 69% do total). Foram encontrados altos índices de sensibilidade antimicrobiana de E. coli às cefalosporinas de segunda e terceira geração (cefuroxima e ceftriaxona, 100%), aos aminoglicosídeos (amicacina, 100%; gentamicina, 96,4%), ao ácido nalidíxico (97,3%), à nitrofurantoina (98,2%) e às quinolonas (ciprofloxacina e norfloxacina, 98,2%); sensibilidade moderada à cefalosporina de primeira geração (cefalotina, 78,4%); baixa sensibilidade à ampicilina (38,7%) e ao sufametoxazol-trimetoprim (55%). CONCLUSÕES: E. coli continua sendo a bactéria mais prevalente das infecções urinárias comunitárias. Conhecendo a baixa sensibilidade in vitro dessa bactéria à sulfametoxazol-trimetoprim e à ampicilina, recomenda-se que tais drogas não sejam eleitas para a terapêutica inicial.

A guideline for the inpatient care of children with pyelonephritis

BACKGROUND AND OBJECTIVES

Febrile urinary tract infections and pyelonephritis are common in children and frequently lead to hospitalization for management, especially in the child who appears toxic. The American Academy of Pediatrics (AAP) practice parameter on the diagnosis, treatment and evaluation of the initial urinary tract infection in febrile infants and young children provides experience and evidence-based guidelines for the practitioner caring for children between the ages of 2 months to 2 years. No established guideline exists for older children and the AAP guideline does not specifically focus on inpatient care.

METHODS

We conducted a comprehensive review of recently published literature and practice guidelines to develop a consensus on the inpatient diagnosis and management of children with pyelonephritis.

RESULTS

Eight recommendations are proposed for the diagnosis and management, including revised guidelines for the imaging studies postpyelonephritis on the basis of current best evidence.

CONCLUSION

Proper diagnosis of pyelonephritis, timely initiation of appropriate therapy and identification of children at risk for renal injury will help to reduce immediate as well as long-term complications due to chronic kidney disease.

Risk factors for recurrent urinary tract infections in a cohort of patients with primary vesicoureteral reflux

BACKGROUND

Knowledge of risk of urinary tract infection (UTI) recurrence in vesicoureteral reflux (VUR) can help clinicians make therapeutic decisions. The aim of this retrospective cohort study was to identify risk factors associated with recurrent urinary tract infection in children with VUR. In addition, a risk score that might predict the chance of UTI recurrence was also proposed.

METHODS

Between 1970 and 2007, 740 patients were diagnosed with VUR and were systematically followed up at a single tertiary Renal Unit. Recurrent UTI was defined as more than 1 episode during follow-up. A binary logistic regression model was applied to identify variables independently associated with recurrent UTIs.

RESULTS

During follow-up, information was obtained on 58,856 person-months. Recurrent UTIs occurred in 120 (16.2%) patients. The overall incidence rate of UTI was 8.4 episodes per 1000 person-months (95% CI, 7.7, 9.2). After adjustment by multivariable analysis, 5 variables were independent predictors of recurrent UTI: UTI as clinical presentation, age < 6 months, female gender, dysfunctional elimination syndrome, and severe grade of reflux. The risk for recurrent UTI was classified as low in 24% of children, medium in 42%, and high in 34%. UTI incidence rates per 1000 person-months were 4.3 (95% CI, 3.2, 5.6), 7.9 (95% CI, 6.7, 9.1), and 11.3 (95% CI, 9.9, 12.8) for low-, medium-, and high-risk groups, respectively.

CONCLUSION

The prediction model of recurrent UTI allows an early recognition of patients at risk for long-term morbidity and might contribute to the formulation of therapeutic strategies.

Clinical aspects of invasive candidiasis in paediatric patients

Candida infections in paediatric patients are an important issue. They are associated with significant mortality, particularly in newborns and those with congenital immunodeficiencies. At present, there is limited knowledge regarding factors associated with an increased risk of developing invasive candidiasis in newborns and those with congenital immunodeficiencies, although there have been a number of studies conducted to characterize these risk factors. These studies have suggested that, in neonates, the most important of these factors is colonization, whereas in paediatric patients with congenital immunodeficiencies, risk factors may differ according to the specific deficiency present. Regarding treatment of invasive candidiasis in paediatric patients, fluconazole is considered an appropriate choice, although the method for determining treatment strategies for each patient should be the same as that used for such decisions in adult patients.

Urinalysis is not reliable to detect a urinary tract infection in febrile infants presenting to the ED

OBJECTIVE

Urinary tract infections are a common source of serious bacterial infections in febrile infants younger than 2 years. Our objective was to compare urinalysis with urine culture in the emergency department evaluation of febrile infants.

METHODS

A febrile infant registry was instituted at a tertiary care hospital treating an average of 55000 patients annually (27% children), from December 2002 to December 2003. Patients were eligible if they were younger than 3 months and had a temperature of at least 38 degrees C or if they were between 3 and 24 months of age and had a temperature of at least 39 degrees C. Data abstracted included age, sex, and temperature. Urinalysis (UA) and urine culture (UCx) results were obtained from electronic hospital archives.

RESULTS

Nine hundred eighty-five patients were entered into the febrile infant registry. Male patients comprised 55%. The mean age of patients was 12.6 months; median was 12 months. Four hundred thirty-five (78% of eligible patients) had both a UA and UCx from the same specimen, and there were 45 (10.3%) positive UCx result. Females accounted for 33 (73%) of 45 positive results. The sensitivity of UA for predicting a positive UCx result was 64% (95% confidence interval [CI], 49%-78%), whereas the specificity was 91% (95% CI, 88%-94%). The positive predictive value was 46% (95% CI, 31%-53%), with a negative predictive value of 96% (95% CI, 93%-97%).

CONCLUSION

Urinalysis is not reliable for the detection of urinary tract infections in febrile infants when compared with urine cultures.

Urinary tract infections caused by Pseudomonas aeruginosa: a minireview

Urinary tract infections (UTIs) are a serious health problem affecting millions of people each year. Infections of the urinary tract are the second most common type of infection in the body. Catheterization of the urinary tract is the most common factor, which predisposes the host to these infections. Catheter-associated UTI (CAUTI) is responsible for 40% of nosocomial infections, making it the most common cause of nosocomial infection. CAUTI accounts for more than 1 million cases in hospitals and nursing homes annually and often involve uropathogens other than Escherichia coli. While the epidemiology and pathogenic mechanisms of uropathogenic Escherichia coli have been extensively studied, little is known about the pathogenesis of UTIs caused by other organisms like Pseudomonas aeruginosa. Scanty available information regarding pathogenesis of UTIs caused by P. aeruginosa is an important bottleneck in developing effective preventive approaches. The aim of this review is to summarize some of the advances made in the field of P. aeruginosa induced UTIs and draws attention of the workers that more basic research at the level of pathogenesis is needed so that novel strategies can be designed.

Urinary tract infections in 1- to 3-month-old infants: ambulatory treatment with intravenous antibiotics

OBJECTIVE

The goal was to examine the feasibility of outpatient management for 1- to 3-month-old infants with febrile urinary tract infections.

METHODS

A cohort study was performed with all children 30 to 90 days of age who were evaluated for presumed febrile urinary tract infections in the emergency department of a tertiary-care pediatric hospital between January 1, 2005, and September 30, 2007. Patients were treated with intravenously administered antibiotics as outpatients in a day treatment center unless they met exclusion criteria, in which case they were hospitalized.

RESULTS

Of 118 infants included in the study, 67 (56.8%) were admitted to the day treatment center and 51 (43.2%) were hospitalized. The median age of day treatment center patients was 66 days (range: 33-85 days). The diagnosis of urinary tract infection was confirmed for 86.6% of patients treated in the day treatment center. Escherichia coli was identified in 84.5% of urine cultures; 98.3% of isolates were sensitive to gentamicin. Six blood cultures (10.3%) yielded positive results, 5 of them for E coli. Treatment with intravenously administered antibiotics in the day treatment center lasted a mean of 2.7 days. The mean number of visits, including appointments for voiding cystourethrography, was 2.9 visits. The rate of parental compliance with day treatment center visits was 98.3%. Intravenous access problems were seen in 8.6% of cases. Successful treatment in the day treatment center (defined as attendance at all visits, normalization of temperature within 48 hours, negative control urine and blood culture results, if cultures were performed, and absence of hospitalization from the day treatment center) was obtained for 86.2% of patients with confirmed urinary tract infections.

CONCLUSIONS

Ambulatory treatment of infants 30 to 90 days of age with febrile urinary tract infections by using short-term, intravenous antibiotic therapy at a day treatment center is feasible.

Diagnosis of urinary tract infections in children

PURPOSE OF REVIEW

Urinary tract infections remain a significant cause of serious bacterial infections in children and can result in chronic kidney disease. Thus, prompt diagnosis and initiation of treatment of urinary tract infections are paramount objectives.

RECENT FINDINGS

A number of advances in technology have allowed expeditious examination of the urine. Recent meta-analyses evaluated the ability of these tests to determine the presence or absence of urinary tract infection in children. In addition, understanding the prevalence of urinary tract infection in various populations will help guide the clinician to the appropriate level of suspicion and the appropriate work-up for urinary tract infection.

SUMMARY

Although culture of the urine remains the gold standard for diagnosing and treating urinary tract infections, technical considerations including method of collection of the urine as well as the time necessary for culture results remain problematic. More rapid techniques include dipstick analyses for the presence of leukocyte esterase or nitrites, microscopic analysis for white blood cells or bacteria, and automated urine cell analyzer to determine bacterial and white blood cell counts in the urine. Recent results indicate it is possible to limit the number of urine cultures performed by eliminating those that have a low probability of being positive. In addition, recent studies reexamining the prevalence of urinary tract infections in various populations indicate that diagnostic testing can be aimed at those patients who are in the higher-risk groups.

Infectious disease hospitalizations among infants in the United States

OBJECTIVE

This study describes the burden and epidemiologic features of infectious disease hospitalizations among infants in the United States.

METHODS

Hospitalizations with an infectious disease listed as a primary diagnosis for infants (<1 year of age) in the United States during 2003 were examined by using the Kids' Inpatient Database. National estimates of infectious disease hospitalizations, hospitalization rates, and various hospital parameters were examined.

RESULTS

During 2003, an estimated 286,739 infectious disease hospitalizations occurred among infants in the United States and accounted for 42.8% of all infant hospitalizations. The national infectious disease hospitalization rate was 7010.8 hospitalizations per 100,000 live births, or approximately 1 infectious disease hospitalization for every 14 infants. The median length of stay was 3 days, and stays totaled >1 million hospital days for infants. Infectious disease hospitalization rates were highest among boys and nonwhite infants. The most commonly listed diagnoses among the infant infectious disease hospitalizations included lower respiratory tract infections (59.0%), kidney, urinary tract, and bladder infections (7.6%), upper respiratory tract infections (6.5%), and septicemia (6.5%). The median cost of an infectious disease hospitalization was $2235, with total annual hospital costs of approximately $690 million, among infants in the United States.

CONCLUSIONS

Infectious disease hospitalizations among infants account for substantial health care expenditures and hospital time in the United States, with respiratory disease hospitalizations constituting more than one half of all hospitalizations. Younger infants, boys, and nonwhite infants were at increased risk for infectious disease hospitalization. Measures to reduce racial disparities and the occurrence of respiratory tract infections should substantially decrease the infectious disease burden among infants.