Nasopharyngeal metatranscriptomics reveals host-pathogen signatures of pediatric sinusitis.

Acute sinusitis (AS) is the fifth leading cause of antibiotic prescriptions in children. Distinguishing bacterial AS from common viral upper respiratory infections in children is crucial to prevent unnecessary antibiotic use but is challenging with current diagnostic methods. Despite its speed and cost, untargeted RNA sequencing of clinical samples from children with suspected AS has the potential to overcome several limitations of other methods. However, the utility of sequencing-based approaches in analysis of AS has not been fully explored. Here, we performed RNA-seq of nasopharyngeal samples from 221 children with clinically diagnosed AS to characterize their pathogen and host-response profiles. Results from RNA-seq were compared with those obtained using culture for three common bacterial pathogens and qRT-PCR for 12 respiratory viruses. Metatranscriptomic pathogen detection showed high concordance with culture or qRT-PCR, showing 87%/81% sensitivity (sens) / specificity (spec) for detecting bacteria, and 86%/92% (sens/spec) for viruses, respectively. We also detected an additional 22 pathogens not tested for in the clinical panel, and identified plausible pathogens in 11/19 (58%) of cases where no organism was detected by culture or qRT-PCR. We assembled genomes of 205 viruses across the samples including novel strains of coronaviruses, respiratory syncytial virus (RSV), and enterovirus D68. By analyzing host gene expression, we identified host-response signatures that distinguished bacterial and viral infections and correlated with pathogen abundance. Ultimately, our study demonstrates the potential of untargeted metatranscriptomics for in depth analysis of the etiology of AS, comprehensive host-response profiling, and using these together to work towards optimized patient care.

Support for the Use of a New Cutoff to Define a Positive Urine Culture in Young Children.

BACKGROUND: Conventional urine culture selects for a narrow range of organisms that grow well in aerobic conditions. In contrast, examination of bacterial gene sequences in the urine provides a relatively unbiased evaluation of the organisms present. Thus, by using 16S ribosomal ribonucleic acid (rRNA) gene amplicon sequencing as the reference standard, we now have the ability to assess the accuracy of urine culture in diagnosing urinary tract infection (UTI). METHODS: We enrolled febrile children 1 month to 3 years of age that underwent bladder catheterization for suspected UTI. Using 16S rRNA gene amplicon sequencing as the reference standard, we calculated the accuracy of urine culture at various cutoffs (10 000, 50 000, and 100 000 colony forming units per milliliter). Children with ≥80% relative abundance of any organism on 16S rRNA gene amplicon sequencing with elevated urinary markers of inflammation were defined as having a UTI. RESULTS: When using a cutoff of 10 000 CFU/mL, the sensitivity and specificity of urine culture were 98% (95% confidence interval [CI]: 93%-100%) and 99% (95% CI: 97%-100%), respectively. Using a cutoff of 50 000 colony forming units per mL decreased sensitivity to 80% (95% CI: 68%-93%) without changing the specificity. Using a cutoff of 100 000 further decreased sensitivity to 70% (95% CI: 55%-84%). CONCLUSIONS: Conventional culture remains an accurate method of diagnosing UTIs in young children; however, these data suggest that a cutoff of 10 000 colony forming units per mL provides the optimal balance between sensitivity and specificity for children undergoing bladder catheterization.

External Validation of the UTICalc with and Without Race for Pediatric Urinary Tract Infection.

OBJECTIVE: To validate externally the UTICalc, a popular clinical decision support tool used to determine the risk of urinary tract infections (UTIs) in febrile children, and compare its performance with and without the inclusion of race and at differing risk thresholds. METHODS: We performed a retrospective, singlecenter case-control study of febrile children (2-24 months) in an emergency department. Cases with culture-confirmed UTI were matched 1:1 to controls. We compared the performance of the original model which included race (version 1.0) to a revised model which did not consider race (version 3.0). We evaluated model performance at risk thresholds between 2% and 5%. RESULTS: We included 185 cases and 197 controls (median age 8.4 months; IQR, 4.4-13.0 months; 60.5% girls). When using UTICalc version 1.0, the model area under the receiver operator characteristic curve (AUROC) was 73.4% (95% CI 68.4%-78.5%), which was similar to the version 3.0 model (73.8%; 95% CI 68.7%-78.8%). When using a 2% risk threshold, the version 3.0 model demonstrated a sensitivity of 96.7% and a specificity of 25.0%, with declines in sensitivity and gains in specificity at higher risk thresholds. Version 1.0 of the UTICalc had 12 false negatives, of whom 10 were Black (83%); whereas version 3.0 had 6 false negatives, of whom 2 were Black (33%). CONCLUSIONS: Versions of the UTICalc with and without race had similar performance to each other with a slight decline from the original derivation sample. The removal of race did not adversely affect the accuracy of the UTICalc.

Moraxella Catarrhalis Infrequently Cultured from Middle Ear Fluid of Children with Acute Otitis Media.

We compared the distribution of organisms in the nasopharynx and the middle ear fluid in 164 episodes of acute otitis media in children 6-35 months of age. In contrast to Streptococcus pneumoniae and Haemophilus influenzae , Moraxella catarrhalis is isolated from the middle ear in only 11% of episodes with nasopharyngeal colonization with this organism.

Identifying Children Likely to Benefit From Antibiotics for Acute Sinusitis: A Randomized Clinical Trial.

Importance: The large overlap between symptoms of acute sinusitis and viral upper respiratory tract infection suggests that certain subgroups of children being diagnosed with acute sinusitis, and subsequently treated with antibiotics, derive little benefit from antibiotic use. Objective: To assess if antibiotic therapy could be appropriately withheld in prespecified subgroups. Design, Setting, and Participants: Randomized clinical trial including 515 children aged 2 to 11 years diagnosed with acute sinusitis based on clinical criteria. The trial was conducted between February 2016 and April 2022 at primary care offices affiliated with 6 US institutions and was designed to evaluate whether symptom burden differed in subgroups defined by nasopharyngeal Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis on bacterial culture and by the presence of colored nasal discharge. Interventions: Oral amoxicillin (90 mg/kg/d) and clavulanate (6.4 mg/kg/d) (n = 254) or placebo (n = 256) for 10 days. Main Outcomes and Measures: The primary outcome was symptom burden based on daily symptom scores on a validated scale (range, 0-40) during the 10 days after diagnosis. Secondary outcomes included treatment failure, adverse events including clinically significant diarrhea, and resource use by families. Results: Most of the 510 included children were aged 2 to 5 years (64%), male (54%), White (52%), and not Hispanic (89%). The mean symptom scores were significantly lower in children in the amoxicillin and clavulanate group (9.04 [95% CI, 8.71 to 9.37]) compared with those in the placebo group (10.60 [95% CI, 10.27 to 10.93]) (between-group difference, -1.69 [95% CI, -2.07 to -1.31]). The length of time to symptom resolution was significantly lower for children in the antibiotic group (7.0 days) than in the placebo group (9.0 days) (P = .003). Children without nasopharyngeal pathogens detected did not benefit from antibiotic treatment as much as those with pathogens detected; the between-group difference in mean symptom scores was -0.88 (95% CI, -1.63 to -0.12) in those without pathogens detected compared with -1.95 (95% CI, -2.40 to -1.51) in those with pathogens detected. Efficacy did not differ significantly according to whether colored nasal discharge was present (the between-group difference was -1.62 [95% CI, -2.09 to -1.16] for colored nasal discharge vs -1.70 [95% CI, -2.38 to -1.03] for clear nasal discharge; P = .52 for the interaction between treatment group and the presence of colored nasal discharge). Conclusions: In children with acute sinusitis, antibiotic treatment had minimal benefit for those without nasopharyngeal bacterial pathogens on presentation, and its effects did not depend on the color of nasal discharge. Testing for specific bacteria on presentation may represent a strategy to reduce antibiotic use in this condition. Trial Registration: ClinicalTrials.gov Identifier: NCT02554383.

Association Between Nasopharyngeal Colonization and Clinical Outcome in Children With Acute Otitis Media.

BACKGROUND: Young children with acute otitis media (AOM) frequently exhibit nasopharyngeal colonization with either Streptococcus pneumoniae, Haemophilus influenzae or both pathogens. We aimed to determine if antibiotics could be spared or shortened in those without nasopharyngeal colonization with either pathogen. METHODS: In 2 separate randomized clinical trials in children aged 6-23 months with stringently-diagnosed AOM, we performed bacterial cultures on nasopharyngeal specimens collected at the time of diagnosis. In the first trial, we compared the efficacy of amoxicillin/clavulanate (amox/clav) administered for 10 days vs. that of placebo, and in the second trial, we compared the efficacy of amox/clav administered for 10 days vs. 5 days. In each trial, we classified children as being colonized with both S. pneumoniae and H. influenzae, S. pneumoniae alone, H. influenzae alone, or neither pathogen, and as experiencing either clinical success or clinical failure at the end-of-therapy visit, based on previously reported a priori criteria. RESULTS: We evaluated 796 children. Among children randomized to amox/clav, those colonized with either S. pneumoniae or H. influenzae or both were approximately twice as likely to experience clinical failure as children not colonized with either pathogen (odds ratio: 1.8; confidence intervals: 1.2-2.9). In contrast, among children randomized to placebo, clinical failure at the end-of-therapy visit was not associated with nasopharyngeal culture results at the time of diagnosis. CONCLUSIONS: Children colonized with either S. pneumoniae or H. influenzae or both have a greater chance of treatment failure than children colonized with neither pathogen.

Biomarkers for febrile urinary tract infection in children.

Background: The current reference standard for pediatric urinary tract infection (UTI) screening, the leukocyte esterase (LE) dipstick test, has suboptimal accuracy. The objective of this study was to compare the accuracy of novel urinary biomarkers to that of the LE test. Methods: We prospectively enrolled febrile children who were evaluated for UTI based on their presenting symptoms. We compared the accuracy of urinary biomarkers to that of the test. Results: We included 374 children (50 with UTI, 324 without UTI, ages 1-35 months) and examined 35 urinary biomarkers. The urinary biomarkers that best discriminated between febrile children with and without UTI were urinary neutrophil gelatinase-associated lipocalin (NGAL), IL-1ß, CXCL1, and IL-8. Of all examined urinary biomarkers, the urinary NGAL had the highest accuracy with a sensitivity of 90% (CI: 82-98) and a specificity of 96% (CI: 93-98). Conclusion: Because the sensitivity of the urinary NGAL test is slightly higher than that of the LE test, it can potentially reduce missed UTI cases. Limitations of using urinary NGAL over LE include increased cost and complexity. Further investigation is warranted to determine the cost-effectiveness of urinary NGAL as a screening test for UTI.

Uromycobiome in infants and toddlers with and without urinary tract infections.

BACKGROUND: The bacterial components of the urobiome have been described in children, both with and without urinary tract infections (UTI). However, less is known about the pediatric uromycobiome: the community of fungi in the urine. The objectives of this study were to describe the uromycobiome in children and determine whether the uromycobiome differs between children with and without UTI. METHODS: This was a cross-sectional study of febrile children less than 3 years of age who presented to the Emergency Department and had a catheterized urine sample sent as part of clinical care. We obtained residual urine for use in this study and identified components of the uromyobiome through amplification and sequencing of the fungal ITS2 region. We then compared the uromycobiome between those with and without UTI. RESULTS: We included 374 children in this study (UTI = 50, no UTI = 324). Fungi were isolated from urine samples of 310 (83%) children. Fungi were identified in a higher proportion of children with UTI, compared to those without UTI (96% vs. 81%, p = 0.01). Shannon diversity index was higher in children with UTI, compared to those without (p = 0.04). Although there were differences in the most abundant taxa between children with and without UTI, there was no significant difference in beta diversity between groups. CONCLUSIONS: Fungi were detected in the majority of catheterized urine samples from children. While a higher proportion of children with UTI had fungi in their urine, compared to children without UTI, there was no difference in the composition of these groups. A higher resolution version of the Graphical abstract is available as Supplementary information.

Cost-Effectiveness of Management Strategies in Recurrent Acute Otitis Media.

OBJECTIVE: To evaluate the cost-effectiveness of tympanostomy tube placementvs nonsurgical medical management, with the option of tympanostomy tube placement in the event of treatment failure, in children with recurrent acute otitis media (AOM). STUDY DESIGN: A Markov decision model compared management strategies in children ages 6-35 months, using patient-level data from a recently completed, multicenter, randomized clinical trial of tympanostomy tube placement vs medical management. The model ran over a 2-year time horizon using a societal perspective. Probabilities, including risk of AOM symptoms, were derived from prospectively collected patient diaries. Costs and quality-of-life measures were derived from the literature. We performed one-way and probabilistic sensitivity analyses, and secondary analyses in predetermined low- and high-risk subgroups. The primary outcome was incremental cost per quality-adjusted life-year gained. RESULTS: Tympanostomy tubes cost $989 more per child than medical management. Children managed with tympanostomy tubes gained 0.69 more quality-adjusted life-days than children managed medically, corresponding to $520 855 per quality-adjusted life-year gained. Results were sensitive to the costs of oral antibiotics, missed work, special childcare, the societal cost of antibiotic resistance, and the quality of life associated with AOM. In probabilistic sensitivity analyses, medical management was favored in 66% of model iterations at a willingness-to-pay threshold of $100 000/quality-adjusted life-year. Medical management was preferred in secondary analyses of low- and high-risk subgroups. CONCLUSIONS: For young children with recurrent AOM, the additional cost associated with tympanostomy tube placement outweighs the small improvement in quality of life. Medical management for these children is an economically reasonable strategy. TRIAL REGISTRATION: ClinicalTrials.gov number, NCT02567825.

Reassessment of the Role of Race in Calculating the Risk for Urinary Tract Infection: A Systematic Review and Meta-analysis.

Importance: A previously reported prediction model included a child's race to estimate risk of urinary tract infection (UTI), but race-conscious medicine encourages investigating how race is likely to be a proxy for other factors that should instead be used for risk prediction. Objectives: To systematically review the available literature to evaluate the robustness of the association between race and UTI and to assess whether other variables could replace race as a variable in a previously developed prediction tool without adversely affecting its accuracy. Data Source: MEDLINE was searched through May 28, 2021. Study Selection: English-language studies that reported data on the prevalence of UTI according to race for children younger than 18 years were included. Data Extraction and Synthesis: Two independent reviewers assessed studies for risk of bias and abstracted data. Random-effects models were used to pool odds ratios, and meta-regression was used to explore heterogeneity. Main Outcomes and Measures: Odds of UTI among non-Black children vs Black children. Results: Sixteen studies (17 845 children) were included. In the primary analysis, which included 11 studies, the pooled odds ratio of UTI among non-Black children was 2.44-fold higher (95% CI, 1.87-3.20) than among Black children. The corresponding odds ratio in studies with low or very low risk of bias was 4.84-fold higher (95% CI, 3.16-7.41; I2 = 0%) among non-Black children than among Black children. Replacing race with history of UTI and duration of fever resulted in a model with similar accuracy (training cohort: overall sensitivity, 96% [95% CI, 94%-98%]; overall specificity, 35% [95%, 32%-38%]; overall area under the receiver operating characteristic curve, 0.80 [95% CI, 0.77-0.82]; validation cohort: overall sensitivity, 97% [95% CI, 90%-100%]; overall specificity, 32% [95% CI, 26%-37%]; overall area under the receiver operating characteristic curve, 0.84 [95% CI, 0.77-0.92]). Conclusions and Relevance: Although previous studies suggested that an association between race and UTI exists, because of the issues associated with the inclusion of race in decision models, we replaced the variable of race with history of UTI and duration of fever in a previously developed risk prediction model and found similar accuracy.

Biomarkers for febrile urinary tract infection in children.

BACKGROUND: The sensitivity and specificity of the leukocyte esterase test for the diagnosis of urinary tract infection (UTI) are suboptimal. Recent studies have identified markers that appear to more accurately differentiate children with and without UTI. The objective of this study was to determine the accuracy of these markers, which included CCL3, IL-8, CXCL1, TNF-alpha, IL-6, IFN-gamma, IL-17, IL-9, IL-2, and NGAL, in the diagnosis of UTI. METHODS: This was a prospective cross-sectional study to compare inflammatory proteins between urine samples from febrile children with a UTI, matched febrile controls without a UTI, and asymptomatic healthy controls. RESULTS: We included 192 children (75 with febrile UTI, 69 febrile controls, and 48 asymptomatic healthy controls). Urinary proteins that best discriminated between febrile children with and without UTI were NGAL, a protein that exerts a local bacteriostatic role in the urinary tract through iron chelation; CCL3, a chemokine involved in leukocyte recruitment; and IL-8, a cytokine involved in neutrophil recruitment. Levels of these proteins were generally undetectable in asymptomatic healthy children. CONCLUSIONS: NGAL, CCL3, and IL-8 may be useful in the early diagnosis of UTI. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01391793) A higher resolution version of the Graphical abstract is available as Supplementary information.

Performance of Conventional Urine Culture Compared to 16S rRNA Gene Amplicon Sequencing in Children with Suspected Urinary Tract Infection.

Because some organisms causing urinary tract infection (UTI) may be difficult to culture, examination of bacterial gene sequences in the urine may provide a more accurate view of bacteria present during a UTI. Our objective was to estimate how often access to 16S rRNA gene amplicon sequencing alters diagnosis and/or clinical management. The study was designed as a cross-sectional study of a convenience sample of children with suspected UTI. The setting was the emergency department or outpatient clinic at six pediatric centers. Participants included children 2 months to 10 years of age suspected of UTI. We categorized the results of urine culture as follows: "likely UTI" (≥100,000 CFU/ml of a single uropathogen), "possible UTI" (10,000 to 99,000 CFU/ml of a uropathogen or ≥100,000 CFU/ml of a single uropathogen plus other growth), and "unlikely UTI" (no growth or growth of nonuropathogens). Similarly, we categorized the results of 16S rRNA gene sequencing into the same three categories using the following criteria: likely UTI (≥90% relative abundance of a uropathogen), possible UTI (50 to 89% relative abundance of a uropathogen), and unlikely UTI (remainder of samples). The main study outcome was concordance between conventional culture results and 16S rRNA gene sequencing. Concordance between the two methods was high in children with likely and unlikely UTI by conventional culture (95% and 87%, respectively). In children with possible UTI according to conventional culture, 71% had a single uropathogen at a relative abundance of ≥90% according to 16S rRNA gene sequencing data. Concordance between conventional culture and 16S rRNA gene amplicon sequencing appears to be high. In children with equivocal culture results, 16S rRNA gene results may provide information that may help clarify the diagnosis. IMPORTANCE Concordance between conventional culture and 16S rRNA gene amplicon sequencing appears to be high. In children with equivocal culture results, 16S rRNA gene results may provide information that may help clarify the diagnosis.

Tympanostomy Tubes or Medical Management for Recurrent Acute Otitis Media.

BACKGROUND: Official recommendations differ regarding tympanostomy-tube placement for children with recurrent acute otitis media. METHODS: We randomly assigned children 6 to 35 months of age who had had at least three episodes of acute otitis media within 6 months, or at least four episodes within 12 months with at least one episode within the preceding 6 months, to either undergo tympanostomy-tube placement or receive medical management involving episodic antimicrobial treatment. The primary outcome was the mean number of episodes of acute otitis media per child-year (rate) during a 2-year period. RESULTS: In our main, intention-to-treat analysis, the rate (±SE) of episodes of acute otitis media per child-year during a 2-year period was 1.48±0.08 in the tympanostomy-tube group and 1.56±0.08 in the medical-management group (P = 0.66). Because 10% of the children in the tympanostomy-tube group did not undergo tympanostomy-tube placement and 16% of the children in the medical-management group underwent tympanostomy-tube placement at parental request, we conducted a per-protocol analysis, which gave corresponding episode rates of 1.47±0.08 and 1.72±0.11, respectively. Among secondary outcomes in the main analysis, results were mixed. Favoring tympanostomy-tube placement were the time to a first episode of acute otitis media, various episode-related clinical findings, and the percentage of children meeting specified criteria for treatment failure. Favoring medical management was children's cumulative number of days with otorrhea. Outcomes that did not show substantial differences included the frequency distribution of episodes of acute otitis media, the percentage of episodes considered to be severe, and antimicrobial resistance among respiratory isolates. Trial-related adverse events were limited to those included among the secondary outcomes of the trial. CONCLUSIONS: Among children 6 to 35 months of age with recurrent acute otitis media, the rate of episodes of acute otitis media during a 2-year period was not significantly lower with tympanostomy-tube placement than with medical management. (Funded by the National Institute on Deafness and Other Communication Disorders and others; ClinicalTrials.gov number, NCT02567825.).

Corticosteroids to prevent kidney scarring in children with a febrile urinary tract infection: a randomized trial.

BACKGROUND: To evaluate the efficacy of adjuvant systemic corticosteroids in reducing kidney scarring. A previous study suggested that use of adjuvant systemic corticosteroids reduces kidney scarring in children radiologically confirmed to have extensive pyelonephritis. Efficacy of corticosteroids for children with febrile urinary tract infection (UTI) has not been studied. METHODS: Children aged 2 months to 6 years with their first febrile UTI were randomized to corticosteroids or placebo for 3 days (both arms received antimicrobial therapy); kidney scarring was assessed using 99mTc-dimercaptosuccinic acid kidney scan 5-24 months after the initial UTI. RESULTS: We randomized 546 children of which 385 had a UTI and 254 had outcome kidney scans (instead of the 320 planned). Rates of kidney scarring were 9.8% (12/123) and 16.8% (22/131) in the corticosteroid and placebo groups, respectively (p = 0.16), corresponding to an absolute risk reduction of 5.9% (95% confidence interval: - 2.2, 14.1). CONCLUSION: While children randomized to adjuvant corticosteroids tended to develop fewer kidney scars than children who were randomized to receive placebo, a statistically significant difference was not achieved. However, the study was limited by not reaching its intended sample size. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov , NCT01391793, Registered 7/12/2011 Graphical abstract.

Urine Specific Gravity and the Accuracy of Urinalysis.

BACKGROUND: A recent study in young infants found that different cutoffs maximized the accuracy of the urine white blood cell count in dilute versus concentrated urine samples. We aimed to confirm this finding and to determine its impact on clinical care. METHODS: We conducted a retrospective analysis of data gathered on consecutive children <24 months of age with visits to the emergency department during a 5-year period. We evaluated the accuracy of screening tests for urinary tract infection (UTI) in dilute and concentrated urine samples. We also calculated the number of children who would have been treated differently in a hypothetical cohort of 1000 children presenting with fever had urine specific gravity (SG) been taken into consideration. RESULTS: We included 10 078 children. The ability to rule in UTI (as measured by the positive likelihood ratio [LR]) was similar in dilute and concentrated urine for the leukocyte esterase test (11.76 vs 10.71, respectively). The positive LR for urine white blood cell count per high-powered field was higher in dilute urine (9.83 vs 6.12). In contrast, the positive LR for the nitrite test was lower in dilute urine (20.54 vs 47.44). Despite these differences, we found little change in the number of children treated with antibiotics in predictive models that took urine SG into consideration. CONCLUSIONS: Although we found that urine SG influences the accuracy of some components of the urinalysis, its inclusion in the decision-making process had negligible effect on the clinical care of children with UTI.

Association of Renal Scarring With Number of Febrile Urinary Tract Infections in Children.

IMPORTANCE: Although prior studies have suggested that the risk of renal scarring gradually increases with each febrile urinary tract infection (UTI), recent and detailed data are lacking. OBJECTIVE: To evaluate how the risk of renal scarring is associated with the number of febrile UTIs. DESIGN, SETTING, AND PARTICIPANTS: A post hoc analysis was performed from June 2018 to April 2019 of data collected in the context of 2 multicenter prospective studies (RIVUR [Randomized Intervention for Children With Vesicoureteral Reflux], conducted from June 2007 to June 2013, and CUTIE [Careful Urinary Tract Infection Evaluation], conducted from May 2008 to October 2013), of children with a first UTI without baseline renal abnormalities who were followed up for 2 years for febrile recurrences. EXPOSURE: Number of known febrile UTIs. MAIN OUTCOMES AND MEASURES: Renal scarring was defined as decreased uptake of tracer associated with the loss of contours or cortical thinning on a technetium 99m dimercaptosuccinic acid renal scan obtained at study exit or approximately 4 months after the last febrile UTI. RESULTS: A total of 345 children were included (307 girls and 38 boys; mean [SD] age, 19.4 [18.2] months; 221 with vesicoureteral reflux and 124 without vesicoureteral reflux). The incidence of renal scarring was 2.8% (95% CI, 1.2%-5.8%) after 1 febrile UTI, 25.7% (95% CI, 12.5%-43.3%) after 2 febrile UTIs, and 28.6% (95% CI, 8.4%-58.1%) after 3 or more febrile UTIs. The odds of renal scarring after a second febrile infection were 11.8 (95% CI, 4.1-34.4) times greater than after a single febrile infection, and the odds of renal scarring after 3 or more febrile infections were 13.7 (95% CI, 3.4-54.4) times greater than after a single febrile infection. CONCLUSIONS AND RELEVANCE: Although relatively few children have 2 febrile UTIs, those who do have a substantially higher risk of renal scarring compared with children with a single febrile UTI. This finding suggests that research should focus on the identification of biomarkers that could noninvasively identify children at risk for subsequent febrile infections. More research is also needed to understand the molecular basis of the increased risk of renal scarring among children with recurrent febrile UTIs.

A method of processing nasopharyngeal swabs to enable multiple testing.

OBJECTIVE: To develop a method to perform multiple tests on a single nasopharyngeal (NP) swab. METHODS: We collected a NP swab on children aged 2-12 years with acute sinusitis and processed it for bacterial culture, viruses, cytokine expression, and 16S ribosomal RNA gene sequencing analysis. During the course of the study, we expand the scope of evaluation to include RNA-sequencing, which we accomplished by cutting the tip of the swab. RESULTS: Of the 174 children enrolled, 126 (72.4%) had a positive bacterial culture and 121 (69.5%) tested positive for a virus. Cytokine measurement, as judged by adequate levels of a housekeeping enzyme (glyceraldehyde 3-phosphate dehydrogenase), appeared successful. From the samples used for 16S ribosomal sequencing we recovered, on average, 16,000 sequences per sample, accounting for a total of 2646 operational taxonomic units across all samples sequenced. Samples used for RNA-sequencing had a mean RNA integrity number of 6.0. Cutting the tip of the swab did not affect the recovery yield for viruses or bacteria, nor did it affect species richness in microbiome analysis. CONCLUSION: We describe a minimally invasive sample collection protocol that allows for multiple diagnostic and research investigations in young children.

Modification of the acute otitis media symptom severity scale.

OBJECTIVE: To modify a parent-reported scale we developed to follow symptoms of young children with acute otitis media (AOM-SOS) with the aim of improving its psychometric properties. STUDY DESIGN: We modified version 4.0 of the scale by increasing the number of response options from 3 to 6. We compared the distribution of scores, internal reliability, construct validity, and responsiveness of versions 4.0 and 5.0 in children diagnosed with acute otitis media (AOM) in 2 studies. For Version 5.0, we also estimated the minimal important difference (MID) and assessed its construct validity. RESULTS: 291 and 70 children were enrolled in the studies evaluating version 4.0 and 5.0, respectively. Version 5.0 had fewer items at the ceiling and better psychometric properties (responsiveness, internal reliability, and test-retest reliability). Changes in the score for Version 5.0 corresponded to changes in clinical status. Factor analysis supported a one-factor solution. Children whose parents reported only a small degree of improvement on the diary (compared to the day before) had a mean decrease in AOM-SOS score of approximately 20%. This value can be used as the MID for this version of the scale. CONCLUSIONS: Modification of the AOM-SOS improved its psychometric properties. Data presented here support the use of Version 5.0 of the AOM-SOS as a measure of change in symptom burden in clinical trials of children with acute otitis media.

Host and Bacterial Markers that Differ in Children with Cystitis and Pyelonephritis.

OBJECTIVE: To determine whether treatment for urinary tract infections in children could be individualized using biomarkers for acute pyelonephritis. STUDY DESIGN: We enrolled 61 children with febrile urinary tract infections, collected blood and urine samples, and performed a renal scan within 2 weeks of diagnosis to identify those with pyelonephritis. Renal scans were interpreted centrally by 2 experts. We measured inflammatory proteins in blood and urine using LUMINEX or an enzyme-linked immunosorbent assay. We evaluated serum RNA expression using RNA sequencing in a subset of children. Finally, for children with Escherichia coli isolated from urine cultures, we performed a polymerase chain reaction for 4 previously identified virulence genes. RESULTS: Urinary markers that best differentiated pyelonephritis from cystitis included chemokine (C-X-C motif) ligand (CXCL)1, CXCL9, CXCL12, C-C motif chemokine ligand 2, INF γ, and IL-15. Serum procalcitonin was the best serum marker for pyelonephritis. Genes in the interferon-γ pathway were upregulated in serum of children with pyelonephritis. The presence of E coli virulence genes did not correlate with pyelonephritis. CONCLUSIONS: Immune response to pyelonephritis and cystitis differs quantitatively and qualitatively; this may be useful in differentiating these 2 conditions.