# Clinical value of C-reactive protein to albumin ratio, aspartate aminotransferase, and platelet-to-lymphocyte ratio in predicting the severity of community-acquired pneumonia in children

## TL;DR

This study shows that blood markers like C-reactive protein to albumin ratio, AST, and platelet-to-lymphocyte ratio can help predict how severe pneumonia is in children.

## Contribution

The study identifies CAR, AST, and PLR as novel and effective predictors of severe pediatric community-acquired pneumonia.

## Key findings

- Children with severe pneumonia had significantly higher CAR, AST, and PLR levels compared to those with mild pneumonia.
- Logistic regression confirmed CAR, AST, and PLR as independent risk factors for severe CAP.
- AST showed the highest predictive accuracy with an AUC of 0.837 for severity.

## Abstract

Community-Acquired Pneumonia (CAP) is a common acute and critical illness in pediatrics and one of the leading causes of death in hospitalized children worldwide. Inflammatory mechanisms play a significant role in pneumonia, and inflammatory markers have shown value in predicting severity in various diseases. This study aimed to explore the predictive value of key inflammatory markers for identifying the severity of pediatric CAP.

A retrospective analysis was conducted on children with CAP, comparing inflammatory markers between mild and severe pneumonia groups. Markers analyzed included Platelet-to-Lymphocyte Ratio (PLR), Aspartate Aminotransferase (AST), and C-Reactive Protein to Albumin Ratio (CAR). Statistical analyses involved group comparisons using appropriate tests for continuous and categorical variables, multivariate logistic regression to identify independent risk factors, and receiver operating characteristic (ROC) curves to evaluate predictive performance (p < 0.05 considered significant).

A total of 303 children were included; 87 with severe pneumonia and 216 with mild pneumonia. Severe cases showed significantly higher levels of CAR (24.52 vs. 0.19 mg/L, p = 0.004), AST (37.67 vs. 7.85 U/L, p = 0.040), and PLR (162.83% vs. 126.55%, p = 0.042) compared to mild cases. Logistic regression confirmed CAR (OR = 1.052, 95% CI: 1.004–1.102, p = 0.004), AST (OR = 1.087, 95% CI: 1.064–1.111, p = 0.002), and PLR (OR = 1.046, 95% CI: 0.996–1.099, p = 0.033) as independent risk factors for severe CAP. ROC analysis showed AST had the highest discriminative power (AUC = 0.837, sensitivity = 78%, specificity = 85%), followed by CAR (AUC = 0.797) and PLR (AUC = 0.721).

High levels of CAR, AST, and PLR are significantly associated with the presence of severe pneumonia in children with CAP and can serve as effective predictive indicators for identifying disease severity and guiding clinical assessment of disease progression.