Breaking Evidence: EuSEM top scoring PEM abstracts 1-3

“Prevalence of respiratory viral infections in febrile young infants with elevated blood biomarkers” by Roberto Velasco MD PhD MSc et al. (Pediatric Emergency Physician, Pediatric Emergency Unit, Rio Hortega University Hospital, Valladolid, Spain)

Deciding which febrile infants require investigation and management for possible bacterial infection is often challenging, even for senior clinicians. Due to this, there has been a lot of work concentrating on risk stratification in febrile infants in recent years. The “step-by-step” approach was published in 2014 and is an algorithm for children less than 90 days old with a temperature > 38 degrees. It classifies children into low, intermediate and high risk and although it demonstrated high sensitivity, specificity was low. The authors of this current study propose that the low specificity may have been due to false positives caused by biomarker elevation secondary to respiratory viruses. They therefore investigated the incidence of viral respiratory infection in febrile infants, comparing those with elevated inflammatory biomarkers to those with normal biomarkers.

The study was a prospective, multicentre cohort study and included febrile children (temperature >38^oc) between the ages of 22 and 90 days. The biomarkers studied were c-reactive protein (CRP), procalcitonin (PCT) and absolute neutrophil count (ANP). Respiratory viruses were tested for using polymerase chain reaction (PCR) on nasopharygeal swabs. Children were divided into a biomarker positive group and a biomarker negative group and the occurrence of positive PCR testing compared between the two. In total, 55 patients were included, of which 10 patients (18.2%) had abnormal biomarkers when using the same cut offs as the step-by-step approach. In this group, 16.7% were PCR-positive for metapneumovirus and 8.3% were positive for parainfluenza 4. No children in the control group had either virus. Enterovirus and rhinovirus were also tested for but the PCR technique used did not allow differentiation between the two. PCR was positive for enterovirus / rhinovirus in 50% of biomarker positive children and 30.3% of biomarker negative children. Overall, although the sample size is small, results suggest that metapneumovirus and influenza may cause a rise in inflammatory biomarkers similar to that seen in bacterial infection. Taking this into account in future clinical decision rules may help reduce the number of false positive results and improve the specificity of these algorithms.

Roberto’s take home message

“Some respiratory viruses might cause elevation of biomarkers in febrile infants. Further research is needed to determine if so, and if those patients might be treated as outpatients.”

Contact Roberto about this work: [email protected]

“Utility of chest X-rays in febrile infants under three months of age: the Maltese scenario” by Ruth Farrugia et al. (Resident Specialist in Paediatrics, Mater Dei Hospital, Malta).

Different countries have different ways of investigating febrile infants. In the United Kingdom, the National Institute for Health and Care Excellent (NICE) recommend performing a chest x-ray (CXR) only in those infants with objective signs of respiratory infection. However, in Malta all febrile children under the age of three months receive a full sepsis screen, including CXR. It is this discrepancy that caused the authors of this study to conduct a retrospective review examining the rate of radiographically confirmed pneumonia in febrile infants in Malta, with a view to changing practice based on the results.

This retrospective case note review was conducted on ward handover records for all children aged less than 90 days with a fever, admitted to a state hospital capable of providing paediatric care between 2014 and 2015. Overall, 147 children had complete records and a CXR, of which 11 (7.5%) had radiographic signs of pneumonia. All radiographs were reported by a paediatric radiologist, blinded to the clinical details. In total, 24 children (16.3%) displayed signs of respiratory distress as defined by any of: tachypnoea, cyanosis, nasal flaring, chest wall recessions, oxygen saturations < 96% or crackles on auscultation. Pneumonia was diagnosed in 5 of the 24 (20.8%) infants with respiratory distress and 6 of the 123 (4.9%) infants without any respiratory signs. This ratio was improved by removing neonates aged less than 29 days from the analysis, with only 2 of 29 (2.2%) infants aged between 29 and 90 days having a positive CXR in the absence of respiratory findings. Overall for all infants, the utility of respiratory signs in diagnosing pneumonia was found to have a sensitivity of 45% (95% CI 18 – 75%) and specificity of 86% (95% CI 79 – 91%).

Due to these results, the study authors have suggested a change in practise in Malta, with febrile children aged between 29 and 90 days no longer requiring a routine CXR if there are no respiratory signs. We look forward to hearing if this occurs. For me, this also highlights that maybe we need to think about neonates and infants separately when designing clinical decision algorithms for febrile infants.

Ruth’s take home message

“Do not hesitate to challenge an established practice. Our findings have shown that performing CXRs in febrile infants between 29 to 90 days old with no respiratory findings are futile and do not aid clinical decision making.”

Contact Ruth about this work: [email protected]

“Can Integrated Pulmonary Index predict hospitalization in children with moderate to severe bronchiolitis?” by Murat Anil et al. (Assoc. Prof., MD/ Clinical Chief of Pediatric Emergency Department in Izmir Tepecik Teaching and Research Hospital, Turkey).

Bronchiolitis is extremely common in young children but there are few effective treatments for it, meaning a large percentage of infants that present to our Emergency Departments are admitted for observation. Being able to predict which infants are likely to require admission early on during their assessment may help with resource planning and bed management. The Integrated Pulmonary Index (IPI) is a score used to provide a real-time measure of a patient’s respiratory status. It ranges from 1 to 10, with 10 representing normal physiology and 1 representing severely deranged parameters requiring immediate intervention. The authors of this study investigated whether the IPI could be used to predict admissions in children with moderate to severe bronchiolitis presenting to a Paediatric Emergency Department in Turkey.

This prospective observational study enrolled 141 patients over a 4-month period. The maximum age of any participant was 2 years, with a median age of 4 months. 71% of the children recruited were hospitalised. Admission criteria for the hospital were: toxic appearance, poor feeding, lethargy, dehydration, hemodynamic instability, apnoea, hypoxemia and those who did not recover their clinical status despite 6 hours of emergency observation. The IPI was calculated prior to treatment and compared to the child’s initial vital signs, clinical severity scoring and venous blood gas results. There was no difference in venous pH, pCO2, oxygen saturations, end-tidal CO2 or clinical severity score between patients admitted and those discharged. IPI was found to be lower in those admitted and this difference reached statistical significance (p = 0.009), although the actual difference was small: children hospitalised had an average IPI of 6 compared to an average of 7 for those discharged. Analysis of the Receiver Operating Characteristics showed an area under the curve of 0.71 (95% CI 0.58 – 0.84), corresponding to a fair performance for a diagnostic test. Overall, for departments who have similar admission criteria to those above, calculation of the IPI may help predict admissions for moderate to severe bronchiolitis. However, full exploration of the sensitivity and specificity and validation of the tool in external populations is likely to be needed before fully implementing it as a diagnostic predictor.

Murat’s take home message

The level of Integrated Pulmonary Index before treatment in children with moderate to severe bronchiolitis may be an effective tool for predicting hospitalization.

Contact Murat about this work: [email protected]