555 Does point of care testing for respiratory viruses alter management of children presenting to the paediatric accident and emergency department?

Background

Febrile and respiratory illnesses constitute a high proportion of presentations to Paediatric Accident and Emergency (A+E).¹ The diagnostic challenge is to determine which of these illnesses have a viral aetiology, and can be managed supportively, and which require cultures and prompt antibiotic administration. Point of Care Testing (POCT) for respiratory viruses provides a rapid result and may support immediate clinical judgement, whereas traditional PCR testing takes 6 – 24 hours. POCT is however more expensive.

Objectives

We aimed to assess the impact of rapid POCT for influenza and respiratory syncytial virus (RSV) on the management of patients attending the Paediatric A&E department at the Royal Victoria Infirmary, Newcastle-upon-Tyne, between December 2019 and January 2020.

Methods

Patients eligible for testing were infants <3 months presenting with fever and respiratory symptoms, children with complex needs (i.e. significant neuro-disability or immuno-compromise) and cases where testing was felt likely to alter management, based on consultant discretion. Data were collected retrospectively about clinical presentation, investigations and antibiotic management.

Results

150 patients were included; most aged between one and four years (38%) followed by those aged <3 months (17%). On POCT, 24% were influenza positive, 31.3% RSV positive and 46% negative. We found a reduction in blood cultures performed in the POCT positive cohorts (19.4% (flu positive group), vs 14.9% (RSV positive group) vs 34.8% (negative group)) and similarly, a reduction in the rate of baseline blood tests taken (25% (flu positive group) vs 27.7% (RSV positive group) vs 55.1% (negative group)). Furthermore, there was a reduction in antibiotic administration in the POCT positive groups (30.6% (flu positive group), vs 40.4% (RSV positive group) vs 50.7% (negative group)). In the <3 months cohort; 57.1% of the negative POCT group had cultures and antibiotics, vs 33.3% of the flu positive and 12.5% of the RSV positive infants. Fever appeared to be a key determinant for antibiotic use in the RSV positive infants. 5 patients of the 150 had a central line in-situ. All presented with fever, had cultures performed and received antibiotics for possible line-related sepsis. The one child with a flu positive POCT received tamiflu in light of their immuno-compromise. Patients with significant neuro-disability and a negative POCT were found more likely to receive antibiotics relative to the negative POCT cohort as a whole (63.6% vs 50.7%), which perhaps reflects the vulnerability of this group.

Conclusions

POCT for influenza and RSV may help avoid septic screening of infants <3 months, and reduce unnecessary blood sampling and antibiotic prescriptions in older children. It is unlikely to be useful in patients with central line access aside from in the case of suspected influenza when tamiflu administration may be warranted. Standard laboratory respiratory virus PCR should be performed where a result is required but will not alter immediate management. Our next objective is to determine the cost-effectiveness of permanent point-of-care testing within our Paediatric A&E department.

Reference

https://adc.bmj.com/content/84/5/390