Biomarkers for differentiating bacterial from viral acute respiratory infections in children

Abstract

Acute respiratory infections (ARI) are the leading cause of morbidity and consultations with a pediatrician in childhood. Although the majority of ARIs are of viral etiology, their clinical differentiation from bacterial infections is often difficult, which leads to overuse of antibiotics and increased antibiotic resistance.

The present review aims to present modern laboratory and biomarker approaches for differentiating viral and bacterial respiratory infections in children.

The classic laboratory parameters – white blood cell count and differential blood count, C-reactive protein (CRP) and procalcitonin (PCT) – are reviewed, as well as their limitations in different clinical scenarios, including atypical bacterial infections and severe viral diseases such as COVID-19 and influenza. New diagnostic markers and protein panels, including Myxovirus resistance protein A (MxA), TRAIL and IP-10, are presented, which show high sensitivity and specificity for determining the etiology of the infection. Combined diagnostic algorithms and BV score are also discussed, which demonstrate significantly better diagnostic accuracy compared to the use of a single marker.

No single laboratory parameter is completely reliable on its own, and the optimal diagnostic approach requires integration of the clinical picture, laboratory data and microbiological studies. The application of combined biomarker panels has the potential to reduce unnecessary antibiotic therapy and improve clinical management in children with acute respiratory infections.

Keywords: c-reactive protein, procalcitonin, serum amyloid, complex panels, leukocytosis

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Corresponding author::

Prof. Gergana Petrova,

Department of Pediatrics,

University Hospital “Aleksandrovska” Sofia, Bulgaria

gal_ps@yahoo.co.uk