Clinical Significance of Procalcitonin, Lactic Acid, and Endotoxin Testing for Children With Severe Pneumonia and Sepsis.

Sepsis is a common complication of severe pediatric pneumonia, characterized by difficulty in treatment, a high treatment cost, high morbidity and mortality, and poor prognosis. The levels of three indicators, procalcitonin (PCT), lactic acid (Lac), and endotoxin (ET), can vary greatly in children with severe pneumonia complicated by sepsis. The study aimed to investigate the clinical significance of PCT, Lac, and ET levels in the serum of children with severe pneumonia complicated by sepsis. The research team performed retrospective study. The study took place at Nantong First People's Hospital in Nantong, Jiangsu, China. Participants were 90 children with severe pneumonia complicated by sepsis and 30 children with severe pneumonia only, all of whom had received treatment in the pediatric intensive care unit of the hospital between January 2018 and May 2020. At baseline, the research team divided the participants into three groups based on their pediatric clinical illness score (PCIS) at 24 h after admission: (1) the extremely critical group-0-70 points (n = 29), (2) the critical group-71-80 points (n = 31), and (3) the noncritical group->80 points (n = 30). The 30 children who had received treatment but who had severe pneumonia only became the control group. The research team: (1) measured the serum PCT, Lac, and ET levels for the four groups at baseline, (2) compared those levels by group, (3) compared those levels by clinical outcome, (4) determined the correlation of the three indicators to the PCIS scores, and (5) identified the predictive value of the three indicators. To compare the levels by clinical outcome and to determine the indicators' predictive values, the team divided participants into two groups according to their clinical outcomes on day 28 of the study: (1) 40 children who died became the death group, and (2) 50 children who survived became the survival group. The serum PCT, Lac, and ET levels in the extremely critical group were the highest, followed by the critical group, the noncritical group, and the control group. The serum PCT, Lac, and ET levels had a significant negative correlation with participants' PCIS scores (r = -0.8203 (PCT), -0.6384 (Lac), -0.6412 (ET), P < .05).The area under the curve (AUC) for the PCT level was 0.7732 (95% CI = 0.6214 to 0.9249, P = .0015), for the Lac level was 0.9533 (95% CI = 0.9036 to 1.000, P < .0001), and for the ET level was 0.8694 (95% CI = 0.7622 to 0.9765, P < .0001). These values indicate that all three indicators were significantly predictive regarding participants' prognoses. The serum PCT, Lac, and ET in children with severe pneumonia complicated by sepsis were abnormally high, and the levels of these indicators were significantly negatively correlated with the PCIS scores. PCT, Lac, and ET may be potential indicators for the diagnosis and prognosis assessment of children with severe pneumonia complicated by sepsis.