Urine collection methods in precontinent children treated at the paediatric emergency department.

AIM: To describe the urine collection methods used in precontinent children presenting at the Paediatric Emergency Department (PED) and compare results and contamination rates. METHODS: Retrospective observational cohort study that included 1678 urine cultures collected in infants <24 months of age between January 2016 and December 2019. Urine cultures were compared based on collection technique, sex and patient age. RESULTS: In total, 60.4% of samples were collected by clean-catch urine collection (CCUC), 26.4% by urethral catheterisation (UC) and 13.2% by urine bag (UB). Contamination rates were 2.9% (95% CI 1.3, 4.4) for UC, 11.3% (95% CI 9.3, 13.2) for CCUC and 23.4% (95% CI 17.8, 29.0) for UB. Significant differences in contamination rates were found between UC and CCUC in the 6-12-month age group (1.9% [95% CI 0.0-4.0] versus 12.0% [95% CI 7.2-16.8] [p < 0.0009]), and between UC and UB for all ages. CONCLUSIONS: CCUC is the most common method for urine culture collection in infants <24 months of age at the PED in our centre. UC has the lowest contamination rates, but significant differences were only observed between CCUC and UC in the 6-12-month age group. CCUC is a non-invasive alternative for urine collection in infants.

Dynamics of Reverse Transcription-Polymerase Chain Reaction and Serologic Test Results in Children with SARS-CoV-2 Infection.

OBJECTIVES: To determine the time to reverse transcription-polymerase chain reaction (RT-PCR) negativity after the first positive RT-PCR test, factors associated with longer time to RT-PCR negativity, proportion of children seroconverting after proven severe acute respiratory syndrome coronavirus 2 infection, and factors associated with the lack of seroconversion. STUDY DESIGN: The Epidemiological Study of Coronavirus in Children of the Spanish Society of Pediatrics is a multicenter study conducted in Spanish children to assess the characteristics of coronavirus disease 2019. In a subset of patients, 3 serial RT-PCR tests on nasopharyngeal swab specimens were performed after the first RT-PCR test, and immunoglobulin G serology for severe acute respiratory syndrome coronavirus 2 antibodies was performed in the acute and follow-up (<14 and ≥14 days after diagnosis) phase. RESULTS: In total, 324 patients were included in the study. The median time to RT-PCR negativity was 17 days (IQR, 8-29 days), and 35% of patients remained positive more than 4 weeks after the first RT-PCR test. The probability of RT-PCR negativity did not differ across groups defined by sex, disease severity, immunosuppressive drugs, or clinical phenotype. Globally, 24% of children failed to seroconvert after infection. Seroconversion was associated with hospitalization, persistence of RT-PCR positivity, and days of fever. CONCLUSIONS: Time to RT-PCR negativity was long, regardless of the severity of symptoms or other patient features. This finding should be considered when interpreting RT-PCR results in a child with symptoms, especially those with mild symptoms. Seroprevalence and postimmunization studies should consider that 11 in 4 infected children fail to seroconvert.

A Tool to Distinguish Viral From Bacterial Pneumonia.

BACKGROUND: Establishing the etiology of community-acquired pneumonia (CAP) in children at admission is challenging. Most of the admitted children with CAP receive antibiotics. We aimed to build and validate a diagnostic tool combining clinical, analytical and radiographic features to differentiate viral from bacterial CAP, and among bacterial CAP, typical from atypical bacteria. METHODS: Design-observational, multi-center, prospective cohort study was conducted in 2 phases. Settings: 24 secondary and tertiary hospitals in Spain. Patients-A total of 495 consecutive hospitalized children between 1 month and 16 years of age with CAP were enrolled. Interventions-A score with 2 sequential steps was built (training set, 70% patients, and validation set 30%). Step 1 differentiates between viral and bacterial CAP and step 2 between typical and atypical bacterial CAP. Optimal cutoff points were selected to maximize specificity setting a high sensitivity (80%). Weights of each variable were calculated with a multivariable logistic regression. Main outcome measures-Viral or bacterial etiology. RESULTS: In total, 262 (53%) children (median age: 2 years, 52.3% male) had an etiologic diagnosis. In step 1, bacterial CAPs were classified with a sensitivity = 97%, a specificity = 48%, and a ROC's area under the curve = 0.81. If a patient with CAP was classified as bacterial, he/she was assessed with step 2. Typical bacteria were classified with a sensitivity = 100%, a specificity = 64% and area under the curve = 0.90. We implemented the score into a mobile app named Pneumonia Etiology Predictor, freely available at usual app stores, that provides the probability of each etiology. CONCLUSIONS: This 2-steps tool can facilitate the physician's decision to prescribe antibiotics without compromising patient safety.

Urine collection methods for infants under 3 months of age in clinical practice.

BACKGROUND: Methods of urine collection used in precontinent children are a controversial issue. Definitive diagnosis of urinary tract infection (UTI) requires an uncontaminated urine culture. We aimed to describe methods used to collect urine for culture in infants under 3 months of age and compare results and contamination rates. METHODS: This retrospective observational cohort study included 721 urine cultures collected from infants <3 months of age at the Hospital Universitario Infanta Sofía, Madrid, between January 2016 and December 2019. Urine cultures were compared based on collection technique, sex, and patient age. RESULTS: Median patient age was 36 days and 54.6% were male. In total, 592 (82.1%) samples were collected using clean-catch urine stimulation technique (CCUST), 77 (10.7%) by urethral catheterization (UC) and 52 (7.2%) by urine bag (UB). Positive cultures were obtained in 11.7% (95% confidence interval [CI] 9.1, 14.3) of CCUST samples and in 28.6% (95% CI 18.5, 38.7) of UC samples (p<0.001). The contamination rate was 13.7% (95% CI 10.9, 16.4] for CCUST, 23.1% (95% CI 11.6, 34.6) for UB and 5.2% (95% CI 0.2, 10.2) for UC, with statistically significant differences (p=0.007) between UB and UC collection. CONCLUSIONS: CCUST is the most commonly used method in our hospital for collecting urine in infants younger than 3 months. The contamination rate of UC is lower but not significantly different to that of CCUST. Urine collection by CCUST serves as a non-invasive alternative to UC for diagnosis of UTI in infants under 3 months of age in routine clinical practice. Graphical abstract.

Performing a urine dipstick test with a clean-catch urine sample is an accurate screening method for urinary tract infections in young infants.

AIM: This study evaluated using urine dipstick tests with the clean-catch method to screen for urinary tract infection (UTI) in febrile infants under 90 days of age. METHODS: We carried out a comparative diagnostic accuracy study of infants under 90 days old, who were studied for unexplained fever without any source, in the emergency room of a hospital in Madrid from January 2011 to January 2013. We obtained matched samples of urine using two different methods: a clean-catch, standardised stimulation technique and catheterisation collection. The results of the leucocyte esterase test and nitrite test were compared with their urine cultures. RESULTS: We obtained 60 pairs of matched samples. A combined analysis of leukocyte esterase and, or, nitrites yielded a sensitivity of 86% and a specificity of 80% for the diagnosis of UTIs in clean-catch samples. The sensitivity of leukocyte esterase and, or, nitrites in samples obtained by catheterisation were not statistically different to the clean-catch samples (p = 0.592). CONCLUSION: Performing urine dipstick tests using urine samples obtained by the clean-catch method was an accurate screening test for diagnosing UTIs in febrile infants of less than 90 days old. This provided a good alternative to bladder catheterisation when screening for UTIs.

Accuracy of a new clean-catch technique for diagnosis of urinary tract infection in infants younger than 90 days of age.

OBJECTIVE: To evaluate the accuracy of diagnosing urinary tract infections using a new, recently described, standardized clean-catch collection technique. METHODS: Cross-sectional study of infants <90 days old admitted due to fever without a source, with two matched samples of urine obtained using two different methods: clean-catch standardized stimulation technique and bladder catheterization. RESULTS: Sixty paired urine cultures were obtained. The median age was 44-days-old. Seventeen percent were male infants. Clean-catch technique sensitivity was 97% (95% CI 82% to 100%) and specificity was 89% (95% CI 65% to 98%). The contamination rate of clean-catch samples was lower (5%) than the contamination rate of catheter specimens (8%). CONCLUSIONS: The sensitivity and specificity of urine cultures obtained using the clean-catch method through the new technique were accurate and the contamination rate was low. These results suggest that this technique is a valuable, alternative method for urinary tract infection diagnosis.

OBJECTIF: Évaluer l'exactitude des diagnostics d'infection urinaire au moyen d'une technique de prélèvement d'urine propre standardisée décrite récemment. MÉTHODOLOGIE: Étude transversale de nourrissons de moins de 90 jours hospitalisés à cause d'une fièvre sans source connue disposant de deux prélèvements d'urine appariés obtenus par deux méthodes différentes : la technique de prélèvement d'urine propre par stimulation standardisée et le cathétérisme vésical. RÉSULTATS: Les chercheurs ont obtenu 60 prélèvements d'urine appariés. Les nourrissons avaient un âge médian de 44 jours, et 17 % étaient de sexe masculin. La sensibilité de la technique par prélèvement d'urine propre s'élevait à 97 % (95 % IC 82 % à 100 %) et sa spécificité, à 89 % (95 % IC 65 % à 98 %). Le taux de contamination des prélèvements d'urine propre était plus faible (5 %) que celui des prélèvements par cathétérisme (8 %). CONCLUSIONS: La sensibilité et la spécificité des cultures d'urine prélevées au moyen de la nouvelle technique de prélèvement d'urine propre étaient précises, et le taux de contamination, faible. Selon ces résultats, cette technique est une solution précieuse pour diagnostiquer les infections urinaires.