Introduction: Psoriasis vulgaris (PV) is characterized by erythrosquamous plaques in skin and associated with systemic inflammation. Platelets modulate immune and inflammatory processes in the skin. Platelets are indicated with PCT which is produced of PLT and the MPV and reflects total platelet mass. PCT is found as a marker that shows platelet activity. PCT is associated with severity of inflammation in some diseases. NLR and PLR in venous blood are increased in systemic inflammatory responses. We aimed to investigate the association between Psoriasis Area and Severity Index (PASI) and platelet indices including plateletcrit (PCT), the value of platelet to lymphocyte ratio (PLR), platelet count (PLT), mean platelet volume (MPV) and the value of neutrophil to lymphocyte ratio (NLR). Materials methods: A total of 172 patients with psoriasis and 128 healthy controls were included in the study. Age, sex, PCT, PLR, NLR, PASI, PLT, neutrophil count (NC) and lymphocyte count (LC), MPV, lipid profile of the patients were recorded. We measured the severity of skin disease using PASI. Results: When compared with controls, patients with psoriasis had higher PCT, platelet count, MPV, PLR and NLR. We observed significant association between the presence of psoriasis and PCT, NLR, MPV. There were significant differences between platelet indices including PLT, PCT, MPV, PLR in the severe and moderate groups. PASI was positively correlated with PCT, MPV and PLR. In ROC analysis, PCT value greater than 0.321 predicted psoriasis with 55% sensitivity and 90% specificity. Using binary logistic regression analysis, we found that PCT, especially those values > 0.321, were independent predictors of psoriasis (OR= 2.810, 95% Cl= 1.28-3.33, p= 0.000). Conclusion: PCT value should be used as a predictor for precense of psoriasis. It could also be highlighted that PCT is a noninvasive, easily available marker and so it can be used in predicting patients with psoriasis.

WOS: 000390174300008

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