Kaolin thromboelastography as an index of diabetic foot severity: Preliminary results in summary

Abstract

Background: This observational study compares the use of thromboelastography (TEG) in the diagnosis of Normal Foot (NP/C), Diabetic Foot (DF), Diabetic Foot with Ulcer (DFU), and Ulcer without Diabetic Foot (WDFU). Research suggests that blood fibrinogen (Fib) concentrations are used to assess the onset and severity of diabetic foot (DF) and to monitor its progression in patients. However, a correlation between TEG and Fib has not been reported in these patients. Methods: This study correlates DF, DFU, NP, and WDFU with α-angle values, clot formation time (k), and Max Amplitude (MA) from Thromboelastography (which reflect Fib function), as well as blood fibrinogen. Patients studied were divided into five groups, and their blood samples underwent TEG. Subsequently, the parameters R, k, α-angle, and MA were analyzed. Primary and secondary hemostatic profile was examined using TEG and fibrinogen levels and was classified as hypo-, hyper-, and normo-coagulable. Results: Presence of an ulcer had a positive effect on the correlation between Fib and MA parameter in TEG both before (=0.65, p=0.36) and after surgery (=0.64, p=0.32), in both diabetic and non-diabetic patients; Median k and fibrinogen levels significantly increased in subjects with DF compared to those without, particularly in those with ulcer (DFU). α angle levels (median) significantly decreased in subjects with DF with ulcer compared to those without (p<0.01). Spearman correlation analysis () showed that α angle and Fib were weakly negatively correlated in the DF classification (= -0.27, p = 0.12) preoperatively and positively ( = 0.25, p = 0.16) postoperatively. α value was positively correlated in the DF (= 0.40, p < 0.05) preoperatively and negatively correlated in the DF ( = -0.2, p = 0.26) postoperatively. ROC curve analysis showed that in patients with pre-surgery fibrinogen levels between 401 and 600 mg/dL, the optimal cutoff point for the α angle to distinguish patients with DF from those without was 53.5°, with a sensitivity and specificity of 63.6%. In the same patients, the optimal cutoff point for the k value was 3.8 min, with a sensitivity of 87.5% and a specificity of 50%. Optimal cutoff point for pre-surgery fibrinogen was 3.98 g/L, with a sensitivity and specificity of 100%. For post-surgery fibrinogen, the cutoff was >4.18 g/L, with a sensitivity of 50% and a specificity of 0%. Optimal cutoff point in patients with pre-surgery fibrinogen >600 mg/dL to assess the risk of progression of diabetic foot was >665 mg/dL, with a sensitivity and specificity of 100%. Optimal cutoff point for the k value was 2.40 min, with a sensitivity and specificity of 100%. Optimal cutoff point in the control group (C) for pre-surgery fibrinogen was 2.78 g/L, with a sensitivity of 66.7% and a specificity of 100%. Conclusion: α angle, k value, and pre-surgery fibrinogen have clinical significance for the risk of onset and development of diabetic foot and its progression to ulceration and may contribute to early diagnosis and early clinical intervention in diabetic foot.