The Usefulness of Serum Sorbitol and Vascular Endothelial Growth Factor A in Predicting Diabetic Retinopathy as Compared to Optical Coherence Tomography

Sanaa Gadbaan Hama Almandlawi*, Muhanad Salah Mawlood
Hawler Medical University, College of Pharmacy, Department of Clinical analysis, Ministry of Higher Education, Kurdistan Region Government, Erbil, Iraq

Article Metrics

CrossRef Citations:
Total Statistics:

Full-Text HTML Views: 2910
Abstract HTML Views: 1161
PDF Downloads: 673
ePub Downloads: 532
Total Views/Downloads: 5276
Unique Statistics:

Full-Text HTML Views: 1099
Abstract HTML Views: 714
PDF Downloads: 476
ePub Downloads: 368
Total Views/Downloads: 2657

Creative Commons License
© 2019 Almandlawi and Mawlood.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: ( This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Hawler Medical University, College of Pharmacy, Department of Clinical analysis, Ministry of Higher Education, Kurdistan Region Government, Erbil, Iraq; Tel: 07504360768;



No specific and sufficient diagnostic biomarkers are currently available for predicting diabetic retinopathy (DR).


This study was conducted to investigate the validity of serum sorbitol and Vascular Endothelial Growth Factor A (VEGF-A) in diagnosing DR and differentiating it from diabetes without retinopathy (DNR). The study also investigated the diagnostic efficiency of these biomarkers when compared to optical coherence tomography OCT.


A cross-sectional study included 164 diabetes mellitus patients: 30 patients with no retinopathy (the control group), 86 patients with non-proliferative diabetic retinopathy (NPDR), and 48 patients with Proliferative Diabetic Retinopathy (PDR). Patients were referred to the Layla Qasim Diabetic Center between November 2016 and October 2017 and an ophthalmologist established a DR diagnosis using OCT. Serum sorbitol and serum VEGF-A were measured for all patients.


By using study biomarkers, the cut-off values of VEGF-A (124.7 ng/ml) and sorbitol (0.3112 mg/ml) were established, and their validity parameters. For sorbitol, the values were as follows: specificity was 75.4, the sensitivity was 80 and 68.3% of observed agreement with the results of the OCT technique. For VEGF-A, the specificity was 73.1 the sensitivity was 80 and 76.2% of the observed agreement. The combined parallel test was applied as negative if both the tests were negative or as positive if either of the tests was positive: a highly significant statistical agreement (Kappa test p <0.001) was found with the gold standard diagnosis (OCT), with 85.4% of observed agreement.


A combination of serum sorbitol and VEGF-A for diagnosing DR and for differentiating DR from DNR patients exhibits a significant agreement with an OCT diagnosis.

Keywords: Diabetic retinopathy, Optical coherence tomography, Serum sorbitol, Specificity, Sensitivity, Vascular endothelial growth factor.