Diabetes Mellitus (DM) is a chronic global disease with a rapidly increasing prevalence. By 2030, it is projected to affect 643 million people, with 2021 data reporting 6.7 million deaths worldwide and over 4 million cases in the Philippines. In Dumaguete City, cases of Type 2 Diabetes Mellitus (T2DM) have also risen from 2019 to 2024. Kidney damage is among the major complications of DM, leading to reduced erythropoietin (EPO) production and the development of renal anemia. Novel biomarkers such as serum neutrophil gelatinase-associated lipocalin (sNGAL) may support early detection, but require further validation. This study therefore aimed to determine the sensitivity and specificity of sNGAL as a potential biomarker for T2DM and examine its correlation with renal anemia indicators.

Thirty-nine Filipino participants from Dumaguete City voluntarily joined the study and were equally categorized into normoglycemic (n = 13), prediabetic (n = 13), and diabetic (n = 13) groups based on established inclusion and exclusion criteria. Anthropometric measurements and medical histories were gathered using a modified structured questionnaire. Diagnosis followed World Health Organization criteria. Blood samples were analyzed for sNGAL and EPO levels using ELISA, while complete blood counts were obtained using a fully automated hematology analyzer. For statistical analysis, the Kruskal–Wallis test was used to compare values among groups. ROC curve analysis assessed the diagnostic accuracy of sNGAL, and Spearman correlation determined its relationship with anemia markers.

Results showed significantly higher sNGAL levels in prediabetic and diabetic groups compared with normoglycemics (p < 0.0001). sNGAL demonstrated excellent diagnostic performance (AUC = 1.00, 95% CI: 1.000–1.000, p < 0.0001). Individuals with sNGAL levels of 13.9 ng/mL were 13 times more likely to be prediabetic or diabetic, identifying this value as a potential diagnostic threshold. However, sNGAL did not differentiate between diabetes and prediabetes (p = 0.1969). Among participants with diabetes, sNGAL showed a significant inverse correlation with EPO levels (r = –0.5172, p = 0.0363), suggesting an association with early reductions in EPO production. No significant correlations were found between sNGAL and red blood cell count, hemoglobin, or hematocrit, indicating that sNGAL may reflect early renal changes before overt anemia develops.

In conclusion, sNGAL is a promising biomarker for distinguishing people with diabetes from normoglycemics and may be linked to decreased EPO production. However, further large-scale studies are necessary to confirm its clinical utility in disease monitoring and early detection.