Harnessing the Power of Generative AI for Clinical Summaries: Perspectives From Emergency Physicians.

STUDY OBJECTIVE: The workload of clinical documentation contributes to health care costs and professional burnout. The advent of generative artificial intelligence language models presents a promising solution. The perspective of clinicians may contribute to effective and responsible implementation of such tools. This study sought to evaluate 3 uses for generative artificial intelligence for clinical documentation in pediatric emergency medicine, measuring time savings, effort reduction, and physician attitudes and identifying potential risks and barriers. METHODS: This mixed-methods study was performed with 10 pediatric emergency medicine attending physicians from a single pediatric emergency department. Participants were asked to write a supervisory note for 4 clinical scenarios, with varying levels of complexity, twice without any assistance and twice with the assistance of ChatGPT Version 4.0. Participants evaluated 2 additional ChatGPT-generated clinical summaries: a structured handoff and a visit summary for a family written at an 8th grade reading level. Finally, a semistructured interview was performed to assess physicians' perspective on the use of ChatGPT in pediatric emergency medicine. Main outcomes and measures included between subjects' comparisons of the effort and time taken to complete the supervisory note with and without ChatGPT assistance. Effort was measured using a self-reported Likert scale of 0 to 10. Physicians' scoring of and attitude toward the ChatGPT-generated summaries were measured using a 0 to 10 Likert scale and open-ended questions. Summaries were scored for completeness, accuracy, efficiency, readability, and overall satisfaction. A thematic analysis was performed to analyze the content of the open-ended questions and to identify key themes. RESULTS: ChatGPT yielded a 40% reduction in time and a 33% decrease in effort for supervisory notes in intricate cases, with no discernible effect on simpler notes. ChatGPT-generated summaries for structured handoffs and family letters were highly rated, ranging from 7.0 to 9.0 out of 10, and most participants favored their inclusion in clinical practice. However, there were several critical reservations, out of which a set of general recommendations for applying ChatGPT to clinical summaries was formulated. CONCLUSION: Pediatric emergency medicine attendings in our study perceived that ChatGPT can deliver high-quality summaries while saving time and effort in many scenarios, but not all.

Preferences for Management of Pediatric Pneumonia: A Clinician Survey of Artificially Generated Patient Cases.

BACKGROUND: It is unknown which factors are associated with chest radiograph (CXR) and antibiotic use for suspected community-acquired pneumonia (CAP) in children. We evaluated factors associated with CXR and antibiotic preferences among clinicians for children with suspected CAP using case scenarios generated through artificial intelligence (AI). METHODS: We performed a survey of general pediatric, pediatric emergency medicine, and emergency medicine attending physicians employed by a private physician contractor. Respondents were given 5 unique, AI-generated case scenarios. We used generalized estimating equations to identify factors associated with CXR and antibiotic use. We evaluated the cluster-weighted correlation between clinician suspicion and clinical prediction model risk estimates for CAP using 2 predictive models. RESULTS: A total of 172 respondents provided responses to 839 scenarios. Factors associated with CXR acquisition (OR, [95% CI]) included presence of crackles (4.17 [2.19, 7.95]), prior pneumonia (2.38 [1.32, 4.20]), chest pain (1.90 [1.18, 3.05]) and fever (1.82 [1.32, 2.52]). The decision to use antibiotics before knowledge of CXR results included past hospitalization for pneumonia (4.24 [1.88, 9.57]), focal decreased breath sounds (3.86 [1.98, 7.52]), and crackles (3.45 [2.15, 5.53]). After revealing CXR results to clinicians, these results were the sole predictor associated with antibiotic decision-making. Suspicion for CAP correlated with one of 2 prediction models for CAP (Spearman's rho = 0.25). Factors associated with a greater suspicion of pneumonia included prior pneumonia, duration of illness, worsening course of illness, shortness of breath, vomiting, decreased oral intake or urinary output, respiratory distress, head nodding, focal decreased breath sounds, focal rhonchi, fever, and crackles, and lower pulse oximetry. CONCLUSIONS: Ordering preferences for CXRs demonstrated similarities and differences with evidence-based risk models for CAP. Clinicians relied heavily on CXR findings to guide antibiotic ordering. These findings can be used within decision support systems to promote evidence-based management practices for pediatric CAP.

Management of Pediatric Pneumonia: A Decade After the Pediatric Infectious Diseases Society and Infectious Diseases Society of America Guideline.

BACKGROUND: Incomplete uptake of guidelines can lead to nonstandardized care, increased expenditures, and adverse clinical outcomes. The objective of this study was to evaluate the impact of the 2011 Pediatric Infectious Diseases Society and Infectious Diseases Society of America (PIDS/IDSA) pediatric community-acquired pneumonia (CAP) guideline that emphasized aminopenicillin use and de-emphasized the use of chest radiographs (CXRs) in certain populations. METHODS: This quasi-experimental study queried a national administrative database of children's hospitals to identify children aged 3 months-18 years with CAP who visited 1 of 28 participating hospitals from 2009 to 2021. PIDS/IDSA pediatric CAP guideline recommendations regarding antibiotic therapy, diagnostic testing, and imaging were evaluated. Segmented regression interrupted time series was used to measure guideline-concordant practices with interruptions for guideline publication and the Coronavirus Disease 2019 (COVID-19) pandemic. RESULTS: Of 315 384 children with CAP, 71 804 (22.8%) were hospitalized. Among hospitalized children, there was a decrease in blood culture performance (0.5% per quarter) and increase in aminopenicillin prescribing (1.1% per quarter). Among children discharged from the emergency department (ED), there was an increase in aminopenicillin prescription (0.45% per quarter), whereas the rate of obtaining CXRs declined (0.12% per quarter). However, use of CXRs rebounded during the COVID-19 pandemic (increase of 1.56% per quarter). Hospital length of stay, ED revisit rates, and hospital readmission rates remained stable. CONCLUSIONS: Guideline publication was associated with an increase of aminopenicillin prescribing. However, rates of diagnostic testing did not materially change, suggesting the need to consider implementation strategies to meaningfully change clinical practice for children with CAP.

Variation in Oophorectomy Rates for Children with Ovarian Torsion across US Children's Hospitals.

In this multicenter study of 1783 children diagnosed with ovarian torsion from 2012 to 2017, 402 children (22.5%) underwent oophorectomy. The odds of oophorectomy were higher in children under 11 years of age, children with public insurance, and children with complex chronic conditions. Future efforts should target a preservation-first approach.

Antibiotic Choice and Clinical Outcomes in Ambulatory Children with Community-Acquired Pneumonia.

OBJECTIVES: To describe antibiotic prescribing patterns in ambulatory children with community-acquired pneumonia and to assess the relationship between antibiotic selection and clinical outcomes. STUDY DESIGN: This was a retrospective cohort study of ambulatory Medicaid-enrolled children 0-18 years of age diagnosed with community-acquired pneumonia from 2010 to 2016. The exposure was antibiotic class: narrow-spectrum (aminopenicillins), broad-spectrum (amoxicillin/clavulanate and cephalosporins), macrolide monotherapy, macrolides with narrow-spectrum antibiotics, or macrolides with broad-spectrum antibiotics. The associations between antibiotic selection and the outcomes of subsequent hospitalization and development of severe pneumonia (chest drainage procedure, intensive care admission, mechanical ventilation) were assessed, controlling for measures of illness severity. RESULTS: Among 252 177 outpatient pneumonia visits, macrolide monotherapy was used in 43.2%, narrow-spectrum antibiotics in 26.1%, and broad-spectrum antibiotics in 24.7%. A total of 1488 children (0.59%) were subsequently hospitalized and 117 (0.05%) developed severe pneumonia. Compared with children receiving narrow-spectrum antibiotics, the odds of subsequent hospitalization were higher in children receiving broad-spectrum antibiotics (aOR, 1.34; 95% CI, 1.17-1.52) and lower in children receiving macrolide monotherapy (aOR, 0.64; 95% CI, 0.55-0.73) and macrolides with narrow-spectrum antibiotics (aOR, 0.62; 95% CI, 0.39-0.97). Children receiving macrolide monotherapy had lower odds of developing severe pneumonia than children receiving narrow-spectrum antibiotics (aOR, 0.56; 95% CI, 0.33-0.93). However, the absolute risk difference was <0.5% for all analyses. CONCLUSIONS: Macrolides are the most commonly prescribed antibiotic for ambulatory children with community-acquired pneumonia. Subsequent hospitalization and severe pneumonia are rare. Future efforts should focus on reducing broad-spectrum and macrolide antibiotic prescribing.

Short- Versus Prolonged-Duration Antibiotics for Outpatient Pneumonia in Children.

OBJECTIVE: To identify practice patterns in the duration of prescribed antibiotics for the treatment of ambulatory children with community-acquired pneumonia (CAP) and to compare the frequency of adverse clinical outcomes between children prescribed short-vs prolonged-duration antibiotics. STUDY DESIGN: We performed a retrospective cohort study from 2010-2016 using the IBM Watson MarketScan Medicaid Database, a claims database of publicly insured patients from 11 states. We included children 1-18 years old with outpatient CAP who filled a prescription for oral antibiotics (n = 121 846 encounters). We used multivariable logistic regression to determine associations between the duration of prescribed antibiotics (5-9 days vs 10-14 days) and subsequent hospitalizations, new antibiotic prescriptions, and acute care visits. Outcomes were measured during the 14 days following the end of the dispensed antibiotic course. RESULTS: The most commonly prescribed duration of antibiotics was 10 days (82.8% of prescriptions), and 10.5% of patients received short-duration therapy. During the follow-up period, 0.2% of patients were hospitalized, 6.2% filled a new antibiotic prescription, and 5.1% had an acute care visit. Compared with the prolonged-duration group, the aORs for hospitalization, new antibiotic prescriptions, and acute care visits in the short-duration group were 1.16 (95% CI 0.80-1.66), 0.93 (95% CI 0.85-1.01), and 1.06 (95% CI 0.98-1.15), respectively. CONCLUSIONS: Most children treated for CAP as outpatients are prescribed at least 10 days of antibiotic therapy. Among pediatric outpatients with CAP, no significant differences were found in rates of adverse clinical outcomes between patients prescribed short-vs prolonged-duration antibiotics.

Management and Outcomes of Children With Nursemaid's Elbow.

STUDY OBJECTIVE: We identify the incidence and predictors of missed fracture and characterize patterns of radiography performance in children with a diagnosis of radial head subluxation in the emergency department (ED) setting. METHODS: We queried the Pediatric Health Information System database for visits by children younger than 10 years and with a diagnosis of radial head subluxation at 1 of 45 pediatric EDs from 2010 to 2018. The frequency of radiography use was assessed overall and between hospitals. Multivariable logistic regression was used to evaluate associations between patient-level characteristics and the outcome of missed fracture (return visit for upper extremity fracture within 7 days of the index visit). RESULTS: We identified 88,466 eligible visits; the median patient age was 2.1 years, 59% of visits were by female patients, and in visits in which laterality was noted, 60% of cases occurred in the left arm. Radiography was performed at 28.5% of visits; hospital rates of radiography performance ranged from 19.8% to 41.7%. Missed upper extremity fractures were observed in 247 cases (0.3% of the cohort). The odds of missed fracture were higher in children older than 6 years (adjusted odds ratio 2.32; 95% confidence interval 1.12 to 4.81), children who underwent radiography at the index visit (adjusted odds ratio 2.52; 95% confidence interval 1.84 to 3.43), and children receiving acetaminophen or ibuprofen (adjusted odds ratio 1.54; 95% confidence interval 1.15 to 2.06). CONCLUSION: Radiographs were obtained for greater than one quarter of children presenting to a pediatric ED with radial head subluxation, with wide variation between hospitals. Missed fractures were rare. Future efforts should aim to reduce unnecessary radiography in this population.

Seasonality of Common Pediatric Infectious Diseases.

BACKGROUND/OBJECTIVE: Traditional sources cite seasonal patterns for common infectious diseases, often based on microbiologic data, but little is known about cyclical trends in clinically diagnosed infectious conditions in the emergency department (ED). We leveraged the publicly available Nationwide Emergency Department Sample database to measure the seasonality of the most common pediatric infectious diseases diagnosed in US EDs. METHODS: We searched the Nationwide Emergency Department Sample database to identify infectious diagnoses comprising at least 1% of all diagnosis codes ascribed to patients 21 years and younger in US EDs from 2009 to 2013. We used Fourier regression to examine seasonal trends in disease and calculated the peak-to-nadir ratio for each infectious condition. RESULTS: Over 20% of pediatric visits during the study period were for infectious conditions. Upper respiratory infection, otitis media, gastroenteritis, urinary tract infection/pyelonephritis, cellulitis/abscess, and pneumonia showed a seasonal pattern that matched trends found in prior regional or microbiologic-based studies. The strongest seasonal trend as measured by goodness of model fit was found in pneumonia (peak-to-nadir incidence ratio of 2.7), followed by otitis media (2.0), cellulitis/abscess (2.0), gastroenteritis (1.6), upper respiratory infection (3.2), and urinary tract infection/pyelonephritis (1.4). Pharyngitis did not show a strong seasonal trend. CONCLUSIONS: Many of the most common pediatric infectious diseases diagnosed in US EDs exhibited seasonal patterns. Large administrative databases can be used to track seasonal disease patterns, with the advantage that they reflect clinician diagnosis beyond microbiologic confirmation. This methodology could aid in resource planning, infection control, and public health educational initiatives.

Evaluation of the Modified Two-Tiered Testing Method for Diagnosis of Lyme Disease in Children.

Conventional two-tiered testing (CTTT) for Lyme disease includes a first-tier enzyme immunoassay (EIA) followed by a supplemental immunoblot, and modified two-tiered testing (MTTT) relies on two different sequential EIAs without the inclusion of an immunoblot. MTTT has shown promising results as an alternative strategy for the diagnosis of Lyme disease in adults but has not yet been evaluated in children. We performed a cross-sectional study of children and adolescents ≤21 years of age undergoing clinical investigation for suspected Lyme disease. Serum specimens were analyzed with both a whole-cell sonicate (WCS) and a C6 EIA, with a supplemental immunoblot if either EIA was positive or equivocal. We compared CTTT (WCS EIA followed by supplemental immunoblot) to MTTT (WCS EIA followed by C6 EIA) using McNemar's test to evaluate for agreement beyond chance alone. We then used a kappa statistic to measure level of the agreement between testing strategies. We included 1,066 serum specimens, of which 156 (14.6%) had a positive CTTT and 165 (15.5%) had a positive MTTT. There were no significant differences between MTTT and CTTT (P = 0.16). Although the overall agreement between MTTT and CTTT was high (kappa, 0.88; 95% confidence interval, 0.84 to 0.92), 33 children had discordant test results. In a cohort of children and adolescents undergoing investigation for suspected Lyme disease, CTTT and MTTT results agreed in most cases. Since immunoblots are time-consuming, laborious, and challenging to interpret, MTTT provides a promising alternate Lyme disease testing strategy for children.

Variation in the evaluation of testicular conditions across United States pediatric emergency departments.

OBJECTIVES: To explore the variation in diagnostic testing and management for males diagnosed with three testicular conditions (testicular torsion, appendix testis torsion, epididymitis/orchitis) using a large pediatric health care database. Diagnostic testing is frequently used in evaluation of the acute scrotum; however, there is likely variability in the use of these tests in the emergency department setting. METHODS: We conducted a cross-sectional study of males with the diagnoses of testicular torsion, appendix testis torsion, and epididymitis/orchitis. We identified emergency department patients in the Pediatric Health Information Systems (PHIS) database from 2010 to 2015 using diagnostic and procedure codes from the International Classification of Diseases Codes 9 and 10. Frequencies of diagnoses by demographic characteristics and of procedures and diagnostic testing (ultrasound, urinalysis, urine culture and sexually transmitted infection testing) by age group were calculated. We analyzed testing trends over time. RESULTS: We identified 17,000 males with the diagnoses of testicular torsion (21.7%), appendix testis torsion (17.9%), and epididymitis/orchitis (60.3%) from 2010 to 2015. There was substantial variation among hospitals in all categories of testing for each of the diagnoses. Overall, ultrasound utilization ranged from 33.1-100% and urinalysis testing ranged from 17.0-84.9% for all conditions. Only urine culture testing decreased over time for all three diagnoses (40.6% in 2010 to 31.5 in 2015). CONCLUSIONS: There was wide variation in the use of diagnostic testing across pediatric hospitals for males with common testicular conditions. Development of evaluation guidelines for the acute scrotum could decrease variation in testing.

Complexity and Severity of Pediatric Patients Treated at United States Emergency Departments.

OBJECTIVE: To compare the complexity and severity of presentation of children in general vs pediatric emergency departments (EDs). STUDY DESIGN: We performed a cross-sectional study of pediatric ED visits using the National Emergency Department Sample from 2008 to 2012. We classified EDs as "pediatric" if >75% of patients were <18 years old; all other EDs were classified as "general." The presence of an International Classification of Diseases, Ninth Revision code for a complex chronic condition was used as an indicator of patient complexity. Patient severity was evaluated with the severity classification system. In addition, rates of critical procedures and hospitalization were assessed. RESULTS: We identified 9.6 million encounters to pediatric EDs and 169 million to general EDs. Younger children account for a greater proportion of visits at pediatric EDs than general EDs; children <1 year of age account for 18% of visits to a pediatric ED compared with 9% of visits to a general ED (P < .01). Encounters at pediatric EDs had greater complexity (5% vs 2%; P < .01). Although severity classification system scores did not significantly differ by ED type, pediatric EDs had greater rates of hospitalization (10% vs 4%). CONCLUSIONS: Pediatric EDs provided care to a greater proportion of medically complex children than general EDs and had greater rates of hospitalization. This information may inform educational efforts in residency or postgraduate training to ensure high-quality care for children with complex health care needs.

Current Approach to the Diagnosis and Emergency Department Management of Appendicitis in Children.

Concerns about radiation exposure have led to a decrease in the use of computed tomography in suspected appendicitis, with increased reliance on ultrasound. Children with suspected appendicitis should be risk stratified using a combination of clinical signs and symptoms, white blood cell count, and ultrasound in order to guide further evaluation and management. Magnetic resonance imaging is a promising imaging modality but remains costly. Ongoing research is evaluating the role of nonoperative management in children with confirmed appendicitis.

Evaluation of the C6 Lyme Enzyme Immunoassay for the Diagnosis of Lyme Disease in Children and Adolescents.

BACKGROUND: The commercially-available C6 Lyme enzyme immunoassay (EIA) has been approved to replace the standard whole-cell sonicate EIA as a first-tier test for the diagnosis of Lyme disease and has been suggested as a stand-alone diagnostic. However, the C6 EIA has not been extensively studied in pediatric patients undergoing evaluation for Lyme disease. METHODS: We collected discarded serum samples from children and adolescents (aged ≤21 years) undergoing conventional 2-tiered testing for Lyme disease at a single hospital-based clinical laboratory located in an area endemic for Lyme disease. We performed a C6 EIA on all collected specimens, followed by a supplemental immunoblot if the C6 EIA result was positive but the whole-cell sonicate EIA result was negative. We defined a case of Lyme disease as either a clinician-diagnosed erythema migrans lesion or a positive standard 2-tiered serologic result in a patient with symptoms compatible with Lyme disease. We then compared the performance of the C6 EIA alone and as a first-tier test followed by immunoblot, with that of standard 2-tiered serology for the diagnosis of Lyme disease. RESULTS: Of the 944 specimens collected, 114 (12%) were from patients with Lyme disease. The C6 EIA alone had sensitivity similar to that of standard 2-tiered testing (79.8% vs 81.6% for standard 2-tiered testing; P = .71) with slightly lower specificity (94.2% vs 98.8% 2; P < .002). Addition of a supplemental immunoblot improved the specificity of the C6 EIA to 98.6%. CONCLUSIONS: For children and adolescents undergoing evaluation for Lyme disease, the C6 EIA could guide initial clinical decision making, although a supplemental immunoblot should still be performed.

False Positive Lyme Disease IgM Immunoblots in Children.

In our cross-sectional sample of 7289 serologic tests for Lyme disease, we identified 167 instances of a positive IgM immunoblot but a negative IgG immunoblot test result. Considering that only 71% (95% CI 64%-78%) of patients had Lyme disease, a positive IgM immunoblot alone should be interpreted with caution to avoid over-diagnosis of Lyme disease.

Diagnosis of Lyme disease in the pediatric acute care setting.

PURPOSE OF REVIEW: We review the current evidence concerning the diagnosis of Lyme disease in children for application in the acute care setting. RECENT FINDINGS: Recent studies suggest that Lyme disease incidence is substantially higher than previously described. Although efforts are ongoing to identify alternative testing strategies, two-tiered serologic testing remains the diagnostic standard in children with compatible clinical syndromes. Published clinical prediction rules can assist clinicians caring for children with potential Lyme disease. SUMMARY: Two-tiered serologic testing remains the mainstay of the diagnosis of Lyme disease. To minimize the risk of a false positive test, serologic testing should be limited to those children with symptoms compatible with Lyme disease with potential exposure to ticks from endemic regions.

Community-Acquired Pneumonia Diagnosis Following Emergency Department Visits for Respiratory Illness.

Community-acquired pneumonia (CAP) is often considered for children presenting to the emergency department (ED) with respiratory symptoms. It is unclear how often children are diagnosed with CAP following an ED visit for respiratory illness. We performed a retrospective case-control study to evaluate 7-day CAP diagnosis among children 3 months to 18 years discharged from the ED with respiratory illness from 2011 to 2021 and who receive care at 4 hospital-affiliated primary care clinics. Logistic regression was performed to assess for predictors of 7-day CAP diagnosis. Seventy-four (0.7%, 95% confidence interval [CI] = 0.6%, 0.9%) of 10 329 children were diagnosed with CAP within 7 days, and fever at the index visit was associated with increased odds of diagnosis (odds ratio [OR] = 3.32, 95% CI = 1.75-6.28). Community-acquired pneumonia diagnosis after discharge from the ED with respiratory illness is rare, even among children who are febrile at time of initial evaluation.

Antibiotic route and outcomes for children hospitalized with pneumonia.

BACKGROUND: Emerging evidence suggests that initial oral and intravenous (IV) antibiotics have similar efficacy in pediatric community-acquired pneumonia (CAP), but further data are needed. OBJECTIVE: We determined the association between hospital-level initial oral antibiotic rates and outcomes in pediatric CAP. DESIGNS, SETTINGS AND PARTICIPANTS: This retrospective cohort study included children hospitalized with CAP at 43 hospitals in the Pediatric Health Information System (2016-2022). Hospitals were grouped by whether initial antibiotics were given orally in a high, moderate, or low proportion of patients. MAIN OUTCOME AND MEASURES: Regression models examined associations between high versus low oral-utilizing hospitals and length of stay (LOS, primary outcome), intensive care unit (ICU) transfers, escalated respiratory care, complicated CAP, cost, readmissions, and emergency department (ED) revisits. RESULTS: Initial oral antibiotics were used in 16% (interquartile range: 10%-20%) of 30,207 encounters, ranging from 1% to 68% across hospitals. Comparing high versus low oral-utilizing hospitals (oral rate: 32% [27%-47%] and 10% [9%-11%], respectively), there were no differences in LOS, intensive care unit, complicated CAP, cost, or ED revisits. Escalated respiratory care occurred in 1.3% and 0.5% of high and low oral-utilizing hospitals, respectively (relative ratio [RR]: 2.96 [1.12, 7.81]), and readmissions occurred in 1.5% and 0.8% (RR: 1.68 [1.31, 2.17]). Initial oral antibiotics varied across hospitals without a difference in LOS. While high oral-utilizing hospitals had higher escalated respiratory care and readmission rates, these were rare, the clinical significance of these small differences is uncertain, and there were no differences in other clinically relevant outcomes. This suggests some children may benefit from initial IV antibiotics, but most would probably do well with oral antibiotics.

Diagnosis and Management of Pneumonia in Infants Less Than 90 Days of Age.

BACKGROUND: Current guidelines and recent studies on pediatric pneumonia pertain to children older than 3 months of age. Little information exists regarding the diagnostic evaluation, management, and outcomes of infants less than 90 days with pneumonia. METHODS: We compared infants <90 days of age diagnosed with pneumonia across 38 US children's hospitals from 2016 to 2021 to children 90 days to 5 years of age. We evaluated whether differences exist in patient characteristics, diagnostic testing, antibiotic treatment, and outcomes between young infants and older children. Additionally, we assessed seasonal variability and trends over time in pneumonia diagnoses by age group. RESULTS: Among 109 796 children diagnosed with pneumonia, 3128 (2.8%) were <90 days of age. Compared with older children, infants <90 days had more laboratory testing performed (88.6% vs 48.8%, P < .001; median number of laboratory tests 4 [interquartile range: 2-5] vs 0 [interquartile range: 0-3] respectively), with wide variation in testing across hospitals. Chest radiograph utilization did not differ by age group. Infants <90 days were more likely to be hospitalized and require respiratory support than older children. Seasonal variation was observed for pneumonia encounters in both age groups. CONCLUSIONS: Infants <90 days with pneumonia were more likely to undergo laboratory testing, be hospitalized, and require respiratory support than children 90 days to 5 years of age. This may reflect inherent differences in the pathophysiology of pneumonia by age, the manner in which pneumonia is diagnosed, or possible overuse of testing in infants.