Novel Immunoassay Stratifies Between Bacterial, Viral Infections in Children

A novel immunoassay, the MeMed BV^Ò score accurately stratifies between pediatric patients with bacterial or viral infections, according to study results presented at IDWeek 2022, held from October 19 to 23, 2022, in Washington, DC.

The BV score uses computational integration of the levels of 3 host proteins, including tumor necrosis factor-related apoptosis-inducing ligand, interferon gamma-induced protein 10, and C-reactive protein.

Researchers evaluated the accuracy of the BV score using data from pediatric patients (N=861) with fever who presented at emergency departments or urgent care centers less than 7 days from symptom onset. Data were sourced from the Apollo (n=89), AutoPilot (n=437), and Opportunity (n=335) studies.

Children were assessed using the MeMed BV score, and BV outcomes were compared with microbiology testing results. Viral infection was defined as a BV score of less than 35. Microbiology positivity was defined as cerebrospinal fluid or blood culture positivity for a pathogen, urine culture with at least 50,000 colony forming units/mL, urinalysis positive for leukocytes or nitrites, throat culture positive for Groups A, C, or G Streptococcus; peritonsillar abscess, or detection of virus.

The study patients were a median age of 1.8 (IQR, 0.9-3.5) years, 42.3% were girls, and 72.7% were diagnosed with respiratory tract or unspecified viral infections.

Microbiology testing revealed the majority of patients (n=811) had viral infection.

Compared with microbiology positivity, the BV tool had a sensitivity of 95.6% (95% CI, 84.9%-99.5%), specificity of 95.4% (95% CI, 93.6%-96.8%), and negative predictive value of 99.7% (95% CI, 98.9%-99.9%). In total, 9.6% patients yielded equivocal BV scores.

The major limitation of this study is the low bacterial infection positivity rate (6%).

According to the researchers, “BV accurately distinguishes bacterial from viral etiology in microbiology confirmed cases and has the potential to support clinical diagnosis in children presenting to acute care settings.”