The Diagnostic Value of Serum Fatty Acid Binding Protein-4 (FABP-4) Level and Angiopitin Like- 4 (ANGPTL-4) in the Diagnosis of Knee Joint Osteoarthritis: Case Control Study

Abstract

Background: Osteoarthritis is one of the most common joint disorders worldwide and it is responsible for significant morbidity and deterioration of quality of life and in particular elderly population (Mora et al., 2018). The diagnosis is based on clinical as well as radiological assessment; however, biochemical investigation plays a little role in the diagnosis, but recent data had suggested a role for some biochemical markers in the pathogenesis as well as in the diagnosis and assessment of disease severity. Aim of the study: the aim of the present study was to evaluate the potential diagnostic role of FABP4 and ANGPTL-4 serum levels in the diagnosis of knee joint osteoarthritis in a sample of Iraqi patients. Patients and methods: This study is done in outpatient consultation clinic of Rhem& medical rehabilitation at Al-Imamain Al-kadhimain teaching hospital, Baghdad - Iraq. A case control study was included two groups, knee osteoarthritis group of patients and the control group. It was executed during the term from first of June 2021 to last of December 2021. Determination of Fatty acid binding protein-4 (FABP-4) level and Angiopitin like- 4 (ANGPTL-4) level was based on ELISA method. Results: Fatty acid binding protein-4 (FABP-4) level and Angiopitin like- 4 (ANGPTL-4) level were signficantly higher in patients group in comparison with control group (p < 0.001). Based on these observations, the diagnostic potential of these markers was assessed using receiver operator characteristic (ROC) curve analysis in order to find the best cutoff value of these markers that can predict a diagnosis of osteoarthritis in terms of sensitivity and specificity and the results were shown in figures 1 and 2 and table 4. The cutoff value of FABP-4 was > 0.588 with 100 % sensitivity, 100 % specificity and 100 % accuracy. The cutoff value of ANGPTL-4 was > 0.522 with 96 % sensitivity, 100 % specificity and 99.4 % accuracy. Conclusion: Higher levels of Fatty acid binding protein-4 (FABP-4) and Angiopitin like- 4 (ANGPTL-4) in patients with knee OA suggest adiagnostic potnetial for these markers; however, the accuracies of these markers are variables in such a way that FABP-4 is the most accurate followed by ANGPTL-4.