Evaluation of serum vascular endothelial growth factor level and findings of nailfold capillaroscopy by dermatoscope in the differential diagnosis of palmoplantar psoriasis and palmoplantar eczema.

Object: This study aimed to evaluate VEGF level, capillaroscopic findings, and these features for differential diagnosis of palmoplantar psoriasis and eczema patients.

Methods: This comparative cross-sectional study included 40 patients clinical and histopathologically diagnosed with eczema or psoriasis (20 psoriasis and 20 eczema) and 30 patients of similar age and gender without inflammatory disease in the control group. Serum samples of patients were collected and analyzed for VEGF by enzyme-linked immunosorbent assay (ELISA) and at the same time, we applied capillaroscopy with computerized dermatoscopy qualitatively and semiquantitatively.

Results: In the qualitative evaluation, a decrease in capillary density and a significant increase of the avascular area was in palmoplantar plaque psoriasis (PPP) and palmoplantar eczema (PPE) patients compared to the control group. In the semiquantitative evaluation, the mean score decreased capillary density was significantly higher in PPE than in the PPP and control groups (p < 0.001). Minor morphological change (tortuous, crossed and enlarged capillary) scores were significantly higher in patients with PPE compared to PPP and control groups (p = 0.011). Major morphological change (mega, meandering, branching, bushy, bizarre, and disorganized polymorphic capillary) score was significantly higher in patients with PPP than PPE and the control group (p < 0.001). Major morphological change and m-PPPASI scores were correlated in PPP patients (p < 0.05). Disorganized capillaries in PPP patients were significantly higher than in the PPE and control groups (p < 0.001). There was no significant correlation between serum VEGF value and clinical severity and capillaroscopy findings of the patients.

Conclusion: Significant morphological changes were detected between PPP, PPE, and control groups in the qualitative and semi-quantitative evaluation of capillaroscopic findings. In the differential diagnosis of PPP and PPE, major morphological change, especially the presence of disorganized polymorphic capillaries, was considered an important finding in the capillaroscopic evaluation. These capillaroscopic findings may be helpful to discriminate eczema and psoriasis. However, there was no significant relationship between serum VEGF level and the patients' capillaroscopic findings and clinical severity.