Advanced and classical parameters of automated complete blood count in the diagnosis of congenital pneumonia in children

Objective. To study the clinical and diagnostic value of the extended parameters of automated complete blood count in patients with congenital pneumonia at different serum concentrations of C-reactive protein (CRP) and procalcitonin (PCT). Materials and methods. A retrospective cohort single-center study was conducted; 203 patients with a confirmed Congenital Pneumonia were included. The extended parameters of automated complete blood count were performed using the hematological analyzer Sysmex XN (Sysmex Co., Japan) and were evaluated according to the serum concentrations of CRP and PCT. All patients were divided into 4 groups: group 1 (serum PCT level <1 ng/ml), group 2 (PCT level >1 ng/ml); group 3 (PCT concentration<10 mg/l), group 4 (PCT concentration>10 mg/l). Results. The RE-NEUT% index turned out to be 9,3 times, TOTAL IG% 3,9 times, TOTAL IG# 2,9 times higher in the second group compared to the first one (p<0.01). When comparing groups 3 and 4, the indicators of RE-NEUT%, RE-NEUT#, TOTAL IG%, TOTAL IG# were higher (p<0,001) in the group 4 than in the group 3 (12,6, 10,8, 4,8, 4,9 times respectively). For the parameters RE-NEUT%, NE-SFL and the neutrophil index NE-SFL/NE-FSC, a high negative predictivity was established relative to the levels of standard markers of inflammation. RE-NEUT% below 2,9, NE-SFL below 45,1, NE-SFL/ NE-FSC index below 0,54 indicate a PCT level below 1 ng/ml with a probability of more than 95% (p<0,0001). Values of RE-NEUT% below 1,8, NESFL below 44,6, NE-SFL/NE-FSC index below 0,51 indicate a serum CRP level below 10 mg/l with a probability of more than 97% (p<0.0001). All the hematological parameters studied, except the white blood cell quantity had significant weak correlation with serum PCT and CRP concentrations. Conclusion. The introduction of such parameters as RE-NEUT%, TOTAL IG%, NE-SFL, and neutrophil index NE-SFL/NE-FSC into routine laboratory practice for examining children with congenital pneumonia or suspected pneumonia may help to reduce the number of examinations of classical biochemical inflammatory markers and improve the assessment of children’s condition both at the admission to hospital and during subsequent monitoring of their condition.