Use Of Chest Radiography Research Articles

Improving Evidence Based Bronchiolitis Care

Bronchiolitis is the number one cause of hospitalization in infants during the first year of life. Clinical guidelines recommend primarily supportive care and discourage use of pharmacotherapies and diagnostics. However, there continues to be widespread use of non-recommended therapies and variation in the use of therapeutic interventions among hospitals in the United States. Here we review evidence-based management of this common disease in order to optimize resource utilization, decrease healthcare costs, and decrease unnecessary hospitalization. Current evidence does not support the routine use of chest radiographs, viral testing or laboratory evaluation in children with bronchiolitis. In addition, routine administration of bronchodilators, including albuterol and nebulized epinephrine, corticosteroids and hypertonic saline are not recommended for infants and children with bronchiolitis. Intravenous or nasogastric hydration and nutritional support, supplemental oxygen, and respiratory support are recommended. Standardization of bronchiolitis care with evidence based institutional clinical pathways spanning ED to inpatient care can help optimize resource utilization while simultaneously improving care of bronchiolitis and reducing hospital length of stays and costs.

Diagnostic Utility of Chest Radiography in Predicting Long-Standing Systemic Arterial Hypertension.

To investigate the association between aortic arch width on frontal chest radiography and systemic hypertension. A total of 200 consecutive patients were included. Relationships between aortic arch width measurement on chest radiography and blood pressure measurement were investigated using Student's t -tests and Fisher's exact tests. Twenty-five patients were normotensive (< 130/90 mmHg), and 175 were hypertensive. Using cut-off values, 136 patients had an aortic arch width ≥ 3.5 cm, and 65 had an aortic arch width ≥ 4 cm. We found a significant relationship between aortic arch width and hypertension (p < 0.001) as well between aortic arch width cut-off values of 3.5 cm and 4 cm and hypertension (p < 0.001 and p < 0.005, respectively). An aortic arch width ≥ 3.5 cm was associated with a positive likelihood ratio (LR) of 2.3, negative LR of 0.39, sensitivity of 73, specificity of 68, positive predictive value of 94, negative predictive value of 26.6, pretest odds of 7, posttest odds of 16, and posttest probability of 94%. An aortic arch width ≥ 4 cm was associated with a positive LR of 4.50, negative LR of 0.70, sensitivity of 36, specificity of 92, positive predictive value of 97, negative predictive value of 17, pretest odds of 7, posttest odds of 31.5, and posttest probability of 97%. Aortic arch width measurement on chest radiography can be used to predict the presence of long-standing systemic arterial hypertension.

Choosing Wisely Campaign: Report Card and Achievable Benchmarks of Care for Children's Hospitals.

In 2013, the Society of Hospital Medicine (SHM) released 5 pediatric recommendations for the Choosing Wisely Campaign (CWC). Our goals were to develop a report card on the basis of those recommendations, calculate achievable benchmarks of care (ABCs), and analyze performance among hospitals participating in the Pediatric Health Information System. Children hospitalized between January 2013 and September 2015 from 32 Pediatric Health Information System hospitals were studied. The quality metrics in the report card included the use of chest radiograph (CXR) in asthma and bronchiolitis, bronchodilators in bronchiolitis, systemic corticosteroids in lower respiratory tract infections (LRTI), and acid suppression therapy in gastroesophageal reflux (GER). ABCs were calculated for each metric. Calculated ABCs were 22.3% of patients with asthma and 19.8% of patients with bronchiolitis having a CXR, 17.9% of patients with bronchiolitis receiving bronchodilators, 5.5% of patients with LRTIs treated with systemic corticosteroids, and 32.2% of patients with GER treated with acid suppressors. We found variation among hospitals in the use of CXR in asthma (median: 34.7%, interquartile range [IQR]: 28.5%-45.9%), CXR in bronchiolitis (median: 34.4%, IQR: 27.9%-49%), bronchodilators in bronchiolitis (median: 55.4%, IQR: 32.3%-64.9%), and acid suppressors in GER (median: 59.4%, IQR: 49.9%-71.2%). Less variation was noted in the use of systemic corticosteroids in LRTIs (median: 13.5%, IQR: 11.1%-17.9%). A novel report card was developed on the basis of the SHM-CWC pediatric recommendations, including ABCs. We found variance in practices among institutions and gaps between hospital performances and ABCs. These findings represent a roadmap for improvement.

Limiting thoracic CT: a rule for use during initial pediatric trauma evaluation

BackgroundDespite increases in imaging guidelines for other body-regions during initial trauma assessment and the demonstrated utility of chest radiographs (CXR), guidelines for use of thoracic computed-tomography (TCT) are lacking. We hypothesized that TCT utilization had not decreased relative to other protocolized CTs, and mechanism and CXR could together predict significant injury independent of TCT. MethodsWe performed a retrospective review of blunt trauma patients ≤18 y.o. (2007–2015) at two level-1 trauma centers who received chest imaging. Baseline characteristics and incidences of body region-specific CT were compared. Injury mechanism, intrathoracic pathology, and interventions among other data were examined (significance: p<0.05). ResultsAlthough other body-region CT incidence decreased (p<0.05), TCT incidence did not change (p=0.65). Of the 2951 patients, 567 had both CXR and TCT, 933 received TCT-only, and 1451 had CXR-only. TCT altered management in 17 patients: 2 operations, 1 stent-placement, 1 medical management, 9 thoracostomy tube placements, and 4 negative diagnostic workups. All clinically significant changes were predicted by vehicle-related mechanism and abnormal CXR findings. ConclusionsTCT utilization has not decreased over time. All meaningful interventions were predicted by CXR and mechanism of injury. We propose a rule, for prospective validation, reserving TCT for patients with abnormal CXR findings and severe vehicle-related trauma. Level of evidenceDiagnostic study, Level III.

Systematic Tuberculosis Screening in Asylum Seekers in Italy.

The preliminary findings of a tuberculosis (TB) screening of asylum seekers performed in a reception center located in northern Italy reveal a post-entry screening prevalence rate of 535 per 100000 individuals screened. This result shows that systematic use of chest radiography is a useful tool for active TB screening among asylum seekers in Italy.

A Comprehensive Approach to Pediatric Pneumonia: Relationship Between Standardization, Antimicrobial Stewardship, Clinical Testing, and Cost.

In September 2012, our institution implemented an emergency department (ED) and inpatient pathway for community-acquired pneumonia (CAP) based on national guideline recommendations. The objective of this study was to determine the relationship between standardizing ED and inpatient care for CAP and antimicrobial stewardship, clinical testing, and cost. We used descriptive statistics, statistical process control, and interrupted time series analysis to analyze measures 12 months before and after implementation. Six hundred thirty-two patients were included. We found an immediate sustained increase in narrow-spectrum antibiotic (ampicillin) use from a baseline of 8-54%. There was a shift toward more guideline-recommended diagnostic testing with an increase in blood cultures and respiratory viral testing among admitted patients (35-63% and 52-84%, respectively). We identified no significant change in ED chest radiography use, mean ED length of stay (LOS), percentage of CAP admissions, or mean inpatient LOS. Costs of care for admitted patients and for patients discharged from the ED were unchanged. Standardizing care for ED and inpatient management of CAP led to immediate and sustained improvements in antimicrobial stewardship and guideline-recommended testing without significantly affecting costs.

Diagnostic Outcomes After Chest Radiograph Interpretation in Patients With Suspected Tuberculosis and Negative Sputum Smears in a High-Burden Human Immunodeficiency Virus and Tuberculosis Setting.

Evaluation of patients with suspected tuberculosis and negative sputum smears for acid-fast bacilli (AFB) is challenging, especially in high human immunodeficiency virus coinfection settings where sputum smears have lower sensitivity for detecting AFB. We examined the utility of chest radiographs for detecting smear-negative pulmonary tuberculosis. Three hundred sixty sputum smear-negative patients who were referred from primary care clinics in the KwaZulu-Natal province of South Africa were evaluated. Chest radiographs were read by experienced pulmonologists using a previously validated Chest X-Ray Reading and Recording System (CRRS). Agreement between observers using CRRS was high at 91% with a Cohen's kappa of 0.64 (95% confidence interval [CI] = 0.52-0.76). Against a reference standard of sputum culture, sensitivity was 93% (95% CI = 86%-97%), whereas specificity was 14% (95% CI = 10%-19%). Performance against clinical diagnosis (following World Health Organization guidelines) was similar with sensitivity of 92% (95% CI = 88%-95%) and specificity of 20% (95% CI = 13%-28%). The low specificity of CRRS in this setting indicates poor diagnostic utility for detecting pulmonary tuberculosis.

The Risk of Mycobacterium tuberculosis Transmission from Pediatric Index Cases to School Pupils.

This study is the largest report on Mycobacterium tuberculosis transmission rate (TR) from children with pulmonary tuberculosis to school pupils. Higher TR (around 21.6%) was observed in contacts of smear-positive children. TR from pediatric smear-negative index cases was around 0. If our data are confirmed, school contacts of a smear-negative index case could be screened only by clinical evaluation and tuberculin skin test, avoiding the routine use of chest radiographs in children less than 5 years of age as well.

Routine use of chest radiographs in the post-operative management of pectus bar removal: necessity or futility.

While there is literature on techniques for pectus bar removal, there are limited reports on post-operative management. This can include obtaining a postoperative chest radiograph (CXR) despite the minimal risk of associated intra-thoracic complications. This is a review of our experience with bar removal and lack of routine post-operative CXR. A single institution retrospective chart review was performed from 2000 to 2015. Patients who underwent a pectus bar removal procedure were included. We assessed operative timing of bar placement and removal, procedure length, intra-operative and post-operative complications and post-operative CXR findings, specifically the rate of pneumothoraces. 450 patients were identified in this study. Median duration of bar placement prior to removal was 35months (interquartile range 30 and 36months). Sixtey-four patients obtained a post-operative CXR. Of these, only one (58%) film revealed a pneumothorax; this was not drained. A CXR was not obtained in 386 (86%) patients with no immediate or delayed complications from this practice. Median follow-up time for all patients was 11 months (interquartile range 7.5-17months). The risk for a clinically relevant pneumothorax is minimal following bar removal. This suggests that not obtaining routine imaging following bar removal may be a safe practice.

The Use of Chest Radiography in Preoperative Assessment for Cardiac Surgery

Purpose: Traditionally, chest radiographs were used to provide information about the heart size, pulmonary vasculature and the lungs. Current guidelines still recommend all patients undergoing cardiac surgery have a preoperative chest X-ray (CXR). With most patients going for cardiac surgery, the use of ECHO, cardiac angiography and pulmonary functions test adequately address those aspects of the preoperative work up. The aim of this study is to assess whether the preoperative CXR provides a change to patient care. Methodology: A retrospective review of all patients undergoing cardiac surgery from Jan 2014-Dec 2014, allowing for at least 1 year follow-up. Emergency cases that did not receive pull work-up were excluded. Results: 262 patients underwent an elective or an urgent in-patient cardiac procedure that allowed for full preoperative workup. 7 patients out of 262 had a pulmonary irregularity noted on CXR, of which 5 progressed to have a CT chest. Only 1 patient had a pulmonary nodule excised at the time of surgery which proved to be benign, otherwise no change in management was seen in this group. All patients had pulmonary function tests which were acceptable to the operating surgeon and the anaesthetist. No patient has subsequently been diagnosed with lung cancer. Conclusion: The use of CXR for preoperative assessment is outdated and provides little useful additive information needed for cardiac surgery. Only patients with clear indications should be referred for radiography which would lead to improving cardiac unit expenditure, patient time and radiation exposure.

Utility of Chest Radiography in Emergency Department Patients Presenting with Syncope.

IntroductionSyncope has myriad etiologies, ranging from benign to immediately life threatening. This frequently leads to over testing. Chest radiographs (CXR) are among these commonly performed tests despite their uncertain diagnostic yield. The objective is to study the distribution of normal and abnormal chest radiographs in patients presenting with syncope, stratified by those who did or did not have an adverse event at 30 days.MethodsWe performed a post-hoc analysis of a prospective cohort of consecutive patients presenting to an urban tertiary care academic medical center with a chief complaint of syncope from 2003–2006. The frequency and findings for each CXR were reviewed, as well as emergency department and hospital discharge diagnoses, and 30-day outcome.ResultsThere were 575 total subjects, 39.7% were male, and the mean age was 57.2 (SD 24.6). Of the 575 subjects, 403 (70.1%) had CXRs performed, and 116 (20.2%) had an adverse event after their syncope. Of the 116 people who had an adverse event, 15 (12.9%) had a positive CXR, 81 (69.8%) had a normal CXR, and 20 (17.2%) did not have a CXR as part of the initial evaluation. Among the 459 people who did not have an adverse event, 3 (0.7%) had a positive CXR, 304 (66.2%) had a normal CXR, and 152 (33.1%) did not have a CXR performed. Fifteen of the 18 patients (83.4%) with an abnormal CXR had an adverse event. Eighty-one of the 385 patients (21.0%) with a normal CXR had an adverse event. Among those who had a CXR performed, an abnormal CXR was associated with increased odds of adverse event (OR: 18.77 (95% CI= [5.3–66.4])).ConclusionSyncope patients with abnormal CXRs are likely to experience an adverse event, though the majority of CXRs performed in the work up of syncope are normal.

Gastroesophageal Reflux Disease (GERD) Is Associated with Worse Outcomes in Patients with Asthma Presenting to the Emergency Department

Introduction: Gastroesophageal Reflux Disease (GERD) is a leading cause of chronic cough. Recent data show that GERD may be present in up to 70% of patients with asthma. Some have implicated both acid and non-acid reflux as an etiological factor in the bronchoconstriction associated with asthma. Furthermore, asthma guidelines recommend management of GERD as a way to treat poorly controlled asthma. However, given the limited body of literature in this field, experts now suggest that GERD may only be a small contributing factor in the pathophysiological mechanisms of asthma. Methods: We performed a retrospective review of the data in the 2013 National Emergency Database Sample (NEDS) to evaluate whether a diagnosis of GERD is associated with a worsening of outcomes in patients presenting to the Emergency Department (ED) with a principal diagnosis of asthma. These outcomes include hospitalization rate, health care utilization rates, length of stay, and cost visits. Results: There were a total of 440,381 ED visits with principal diagnosis of asthma in the United States. 54.3% of the patients were female, and mean (SD) age at visit was 32(16). In 20,610 (4.7%) of these visits diagnosis of GERD was also recorded for the patient. After adjusting for age, sex, and number of diagnoses, GERD was associated with an increased the risk of admission by 23% (RR 1.21, 95% CI 1.16-1.26,p < 0.001). A diagnosis GERD was also associated with a lower cost of medical care, with an average savings of $4,973 per patient (95% CI 5668-4277, p < 0.001). GERD was associated with significantly more frequent use of nebulizers in the ED (RR 1.24, 95%CI 1.12-1.39, p < 0.001) and chest Computed Tomography (CT) scans (RR 1.66, 95%CI 1.05-2.62, p=0.029), but not with use of chest radiographs (RR 1.05, 95%CI 0.94-1.17, p=0.425). GERD was also associated with a shorter hospital stay, leading to an average difference of about 8 hours comparing patients with GERD and those without (RR 0.28, 95%CI 0.35-0.22,p < 0.001). Conclusion: Our data show that GERD may play a large role in asthma exacerbations and visits to the ED. Furthermore, compared to those without GERD, patients with asthma who have GERD tend to need more diagnostic testing, hospital admissions, and increased costs of health care.

Staging Rectal Cancer: The Utility of Chest Radiograph and Chest Computed Tomography

The National Comprehensive Cancer Network recommends that patients who are newly diagnosed with rectal cancer undergo staging CT scan of the chest. It is unclear whether posteroanterior and lateral chest radiography (X-ray) alone would provide adequate staging for most of these patients. A retrospective review was performed on all patients who had a two-view chest X-ray along with a chest CT for rectal cancer staging from 2007 to 2015. A total of 74 patients had both modalities. Sixty-three (85%) had a normal chest X-ray and 11 (15%) had an abnormal chest X-ray. Of the 63 patients with a normal chest X-ray, 40 (63%) had a corresponding normal chest CT and 23 (37%) had a lesion only noted on chest CT. Four patients (17%) in the latter group had metastatic cancer to the lung at the time of workup and four out of five of the tumors found to metastasize were within 5 cm from the anal verge. Our data suggest that a staging chest X-ray is unlikely to diagnose metastatic lungs lesions from a primary rectal cancer. Conversely, staging chest CT will accurately stage metastatic disease but will also reveal benign lung lesions in this patient population.

Utility of chest radiographs in rapid access tuberculosis clinic

Purpose: To determine (1) factors that are important in coding chest radiographs (CXR) as possible TB and

Message in a bottle. The use of chest radiography for diagnosis of pericardial effusion.

IntroductionThe diagnosis of pericardial effusion may be elusive, and only diagnosed with echocardiography.Case reportsHere we report the cases of two patients who presented to the emergency centre (EC) with dyspnoea, and their chest X-rays (CXR) revealed the “water bottle sign”, which is the typical appearance of the cardiac silhouette that is present when there is a large pericardial effusion.DiscussionThis clinched the diagnosis of pericardial effusion, where the diagnosis may have otherwise been delayed. We discuss these cases, and the relevant literature and discuss the benefits of standard chest radiography in aiding in the diagnosis of pericardial effusion.

ACR Appropriateness Criteria Fever Without Source or Unknown Origin—Child

The cause of fever in a child can often be determined from history, physical examination, and laboratory tests; infections account for the majority of cases. Yet in 20%, no apparent cause can be found, designated as fever without source (FWS). The yield of chest radiography in children with FWS is low, and it is usually not appropriate. However, in children with respiratory signs, high fever (>39°C), or marked leukocytosis (≥20,000/mm3), chest radiography is usually appropriate, as it has a higher yield in detecting clinically occult pneumonia. In newborns with FWS, there is higher risk for serious bacterial infection, and the routine use of chest radiography is controversial. In children with neutropenia, fever is a major concern. In some clinical circumstances, such as after hematopoietic stem cell transplantation, chest CT scan may be appropriate even if the results of chest radiography are negative or nonspecific, as it has higher sensitivity and can demonstrate specific findings (such as lung nodule and “halo sign”) that can guide management. In a child with prolonged fever of unknown origin despite extensive medical workup (fever of unknown origin), diagnosis is usually dependent on clinical and laboratory studies, and imaging tests have low yield.The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Trends in Periodic Surveillance Testing for Early-Stage Uterine Cancer Survivors.

To examine the use of periodic surveillance testing for early-stage endometrial cancer survivors. We performed a population-based analysis using the Surveillance, Epidemiology, and End Results-Medicare database, which was used to identify patients with stage I-II endometrioid endometrial cancer treated from 1992 to 2011. Three surveillance periods (7-18, 19-30, 31-42 months) after hysterectomy were examined. Use of vaginal cytology and imaging were quantified. We identified 17,638 patients. From 1992 to 2011, the use of chest radiography decreased (46.3-34.2%) during the first surveillance period, whereas imaging with chest computed tomography (CT) (0.9-12.6%), abdominopelvic CT (11.7-24.8%), and positron emission tomography (0-2.9%) increased (P<.001 for all). The use of cytology increased from 68.5% in 1992 to 72.3% in 2007 and then decreased to 66.9% in 2011 (P=.02). The mean number of cytologic samples obtained per patient increased from 1.3 in 1992 to 1.6 in 2008 and then declined to 1.3 in 2011, whereas the mean per patient number of chest CTs (0.02-0.2), abdominopelvic CTs (0.2-0.4), and positron emission tomographies (0-0.03) rose from 1992 to 2011. In 2011, 49.3% underwent radiologic surveillance 7-18 months after diagnosis, whereas 11.9% underwent two or more radiologic assessments in combination with cytology. These findings were similar for surveillance periods 2 and 3. The use of chest radiography has decreased and use of cytology has started to decline. However, the use of more costly imaging modalities is increasing despite a lack of evidence for the efficacy of these tests for early-stage endometrial cancer survivors.

Practice Pattern Variation in the Care of Children With Acute Asthma.

Pediatric asthma is a highly prevalent disease, affecting over 7 million U.S. children and accounting for 750,000 annual emergency department (ED) visits. Guidelines from the National Asthma Education and Prevention Program recommend limited use of chest radiography (CXR), complete blood counts (CBCs), and antibiotics when managing acute exacerbations of asthma. However, studies suggest frequent overutilization of these resources. The objective was to evaluate differences between pediatric and general EDs in rates of CXRs, CBCs, and use of antibiotics for pediatric asthma exacerbations. This was a repeated cross-sectional analysis of data from the National Hospital Ambulatory Medical Care Survey from 2000 through 2010 of CXR, CBCs, and antibiotics during ED visits for pediatric acute asthma exacerbations. Multivariable logistic regression was performed to identify differences in asthma management by ED type (pediatric vs. general) after adjusting for demographic covariates. There were 3,313 observations, representing an estimated 10.9 million (95% confidence interval [CI] = 9.7 to 12.1 million) ED visits for acute asthma without bacterial coinfection. Of these, 17.4% occurred in pediatric EDs. Multivariable logistic regression revealed that visits to pediatric EDs were less likely to include CXRs (adjusted odds ratio [AOR] = 0.39; 95% CI = 0.25 to 0.60), CBCs (AOR = 0.42; 95% CI = 0.22 to 0.80), and antibiotics (AOR = 0.50; 95% CI = 0.31 to 0.82) after adjustment for race/ethnicity, triage level, academic ED, metropolitan statistical area, and geographic region. There are substantial differences in diagnostic testing and antibiotic usage for management of acute exacerbations of asthma by ED type, suggesting potential resource overuse in general EDs. Future studies should focus on evaluating the effect of quality improvement efforts for ED asthma management.

A Multicenter Collaborative to Reduce Unnecessary Care in Inpatient Bronchiolitis

Evidence-based Guidelines for acute viral bronchiolitis recommend primarily supportive care, but unnecessary care remains well documented. Published quality improvement work has been accomplished in children's hospitals, but little broad dissemination has been reported outside of those settings. We sought to use a voluntary collaborative strategy to disseminate best practices to reduce overuse of unnecessary care in children hospitalized for bronchiolitis in community settings. This project was a quality improvement collaborative consisting of monthly interactive webinars with online data collection and feedback. Data were collected by chart review for 2 bronchiolitis seasons, defined as January, February, and March of 2013 and 2014. Patients aged <24 months hospitalized for bronchiolitis and without chronic illness, prematurity, or intensive care use were included. Results were analyzed using run charting, analysis of means, and nonparametric statistics. There were 21 participating hospitals contributing a total of 1869 chart reviews to the project, 995 preintervention and 874 postintervention. Mean use of any bronchodilator declined by 29% (P = .03) and doses per patient decreased 45% (P < .01). Mean use of any steroids declined by 68% (P < .01), and doses per patient decreased 35% (P = .04). Chest radiography use declined by 44% (P = .05). Length of stay decreased 5 hours (P < .01), and readmissions remained unchanged. A voluntary collaborative was effective in reducing unnecessary care among a cohort of primarily community hospitals. Such a strategy may be generalizable to the settings where the majority of children are hospitalized in the United States.

Differences upon admission and in hospital course of children hospitalized with community-acquired pneumonia with or without radiologically-confirmed pneumonia: a retrospective cohort study.

BackgroundThe use of chest radiograph (CXR) for the diagnosis of childhood community-acquired pneumonia (CAP) is controversial. We assessed if children with CAP diagnosed on clinical grounds, with or without radiologically-confirmed pneumonia on admission, evolved differently.MethodsChildren aged ≥ 2 months, hospitalized with CAP diagnosed on clinical grounds, treated with 200,000 IU/Kg/day of aqueous penicillin G for ≥ 48 h and with CXR taken upon admission, without pleural effusion, were included in this retrospective cohort. One researcher, blinded to the radiological diagnosis, collected data on demographics, clinical history and physical examination on admission, daily hospital course during the first 2 days of treatment, and outcome, all from medical charts. Radiological confirmation of pneumonia was based on presence of pulmonary infiltrate detected by a paediatric radiologist who was also blinded to clinical data. Variables were initially compared by bivariate analysis. Multi-variable logistic regression analysis assessed independent association between radiologically-confirmed pneumonia and factors which significantly differed during hospital course in the bivariate analysis. The multi-variable analysis was performed in a model adjusted for age and for the same factor present upon admission.Results109 (38.5 %) children had radiologically-confirmed pneumonia, 143 (50.5 %) had normal CXR and 31 (11.0 %) had atelectasis or peribronchial thickening. Children without radiologically-confirmed pneumonia were younger than those with radiologically-confirmed pneumonia (median [IQR]: 14 [7–28 months versus 21 [12–44] months; P = 0.001). None died. The subgroup with radiologically-confirmed pneumonia presented fever on D1 (33.7 vs. 19.1; P = 0.015) and on D2 (31.6 % vs. 16.2 %; P = 0.004) more frequently. The subgroup without radiologically-confirmed pneumonia had chest indrawing on D1 (22.4 % vs. 11.9 %; P = 0.027) more often detected. By multi-variable analysis, Fever on D2 (OR [95 % CI]: 2.16 [1.15-4.06]) was directly and independently associated with radiologically-confirmed pneumonia upon admission.ConclusionThe compared subgroups evolved differently.