Alkaline phosphatase as an adjunct for Appendicitis Inflammatory Response score

Appendicitis is a common acute surgical condition globally, primarily diagnosed through clinical assessment, imaging, and laboratory markers. The Appendicitis Inflammatory Response (AIR) score, which utilises various clinical and laboratory parameters, is often employed to predict appendicitis more accurately. However, diagnostic improvements, especially in ambiguous cases, are needed. Alkaline phosphatase (ALP), a marker linked to inflammation, may enhance the AIR score's diagnostic precision by reflecting the severity of inflammation more accurately. This study aims to assess the impact of integrating ALP levels into the AIR score.

This observational study was conducted at Saveetha Medical College and Hospital, Saveetha Institute of Medical and Technical Sciences. Patients suspected of acute appendicitis were evaluated over one year (2022-2023). Patients were assessed using the AIR score with and without the inclusion of ALP levels. ALP levels were measured along with standard laboratory markers. Statistical analyses were performed using SPSS, assessing the specificity, sensitivity, NPV, and PPV of the AIR score.

A total of 112 patients enrolled: 64 males (57%) and 48 females (43%), most presented with right lower quadrant pain. The median ALP level was 215 IU/L. Initial analyses showed an AIR score sensitivity of 80% and specificity of 75%, which improved to 92% and 85%, respectively, with the inclusion of ALP. The ROC curve analysis indicated an AUC improvement from 0.78 to 0.92 with ALP. This established an optimal ALP cutoff at 90 IU/L. The p-value for AIR is 0.012, whereas the P-value for AIR+ALP is 0.001.

Integrating ALP into the AIR score significantly enhances its diagnostic accuracy for appendicitis. This suggested ALP's potential as a valuable biomarker in appendicitis diagnosis. This integration could improve clinical decision-making and patient outcomes, reducing unnecessary surgeries and associated healthcare costs.