Abstract:Objective To investigate the value of serum 25-hydroxyvitamin D3 [25(OH)D3], eosinophil percentage (EOS%), and CT Bhalla score in assessing the disease severity and prognosis in bronchopneumonia.Methods A total of 93 bronchopneumonia patients admitted to Fuyang People’s Hospital from November 2024 to March 2025 were enrolled and stratified into the mild (n = 59) and severe (n = 34) groups based on disease severity, with 59 cases of healthy individuals undergoing health check-ups in the hospital during the same period as controls. Serum levels of 25(OH)D3 and EOS% were measured, and chest CT scans were performed for Bhalla scoring in each group. Differences in 25(OH)D3 levels, EOS%, and Bhalla scores, along with prognosis in patients of varying severity, were compared among the three groups. Multivariable linear regression was performed to identify independent factors influencing disease severity, and receiver operating characteristic curve analysis was used to evaluate the predictive performance of combined indicators.Results The severe group showed higher rates of smoking, pre-existing chronic diseases, and chest tightness, as well as higher NEUT%, compared to the mild group (P < 0.05). The rate of fever was lower in the severe group than in the mild group (P < 0.05). Both severe and mild groups had lower levels of 25(OH)D3 and EOS% than the control group (P < 0.05), and the severe group exhibited significantly lower 25(OH)D3 and EOS% levels than the mild group (P < 0.05). The CT Bhalla score was higher in the severe group than in the mild group (P < 0.05). Total length of hospital stay was longer and medical costs were higher in the severe group (P < 0.05). Multivariable logistic regression analysis revealed that low levels of 25(OH)D3 [O^R = 0.586 (95% CI: 0.431, 0.797) ], low EOS% [O^R = 0.391 (95% CI: 0.167, 0.915) ], and high CT Bhalla scores [O^R = 1.251 (95% CI: 1.017, 1.539) ] were identified as risk factors for disease exacerbation. The combination of serum 25(OH)D3, EOS%, and CT Bhalla scores yielded the largest area under the curve (AUC) of 0.906 (95% CI: 0.846, 0.966), with a sensitivity of 97.1% (95% CI: 85.1%, 99.9%), a specificity of 78.0% (95% CI: 65.3%, 87.7%) and a Youden index of 0.750.Conclusion Serum 25(OH)D3, EOS%, and CT Bhalla scores serve as effective indicators for assessing bronchopneumonia severity, with severe cases associated with higher medical costs. Combined detection of these indicators aids clinical evaluation and healthcare resource management.