Validation of the Stool Alkaline Phosphatase (STAP) Test for Predicting Vulnerability to Diabetes

Introduction and Objective: Intestinal alkaline phosphatase (IAP, alternatively known as stool alkaline phosphatase, STAP) is an endotoxin-detoxifying, anti-inflammatory gut enzyme secreted by enterocytes and excreted with stool. A 5-year prospective cohort study showed that IAP deficiency (IAPD) leads to type 2 diabetes mellitus (T2DM) (Risk Ratio: 14). Our objective is to validate the STAP test (assay) in predicting vulnerability to T2DM. Methods: We determined the linearity, precision, detection limit, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the STAP test. Results: The reagents were stable, and the STAP test was valid based on the conventionally accepted parameters. We calculated the sensitivity, specificity, PPV, and NPV of the STAP test, and the values are shown below (Table 1). For a test to be useful in diagnosing a disease, the ‘sensitivity + specificity’ score should be >1.5. The ‘sensitivity + specificity’ of STAP test is (93.33% + 67.34%) = 1.61establishing the usefulness of STAP test in predicting the development of T2DM in the future. Conclusion: The STAP test diagnoses vulnerability to diabetes. Disclosure: B.K. Malo: Other Relationship; Stapgen LLC, Foster Street Dental LLC. T. Sarker: None. J. Alam: None. A. Mottalib: None. S. Islam: None. M. Hasanat: None. A.K. Khan: None. M.S. Malo: None.