RESUMEN
BACKGROUND AND OBJECTIVE: Rheumatoid arthritis (RA), insulin-dependent diabetes mellitus (IDDM), inflammatory bowel disease, systemic lupus erythematosus (SLE) and multiple sclerosis (MS) are some of the autoimmune diseases related to the decreases in Vitamin D levels. The same immunological properties as psoriasis, such as Th1/Th2 dysregulation, are seen in all of them. This study aims to compare 25-hidroksi Vitamin D (25-OHD) serum concentrations in patients with psoriasis and psoriatic arthritis. METHODS: This study includes 91 outpatients; 48 of these patients were chosen randomly among the psoriasis (PS) patients from the dermatology department of the researchers' hospital. Forty-three of them were chosen among the psoriatic arthritis (PsA) patients matching the age and gender criteria from the rheumatology department of the researchers' hospital. In this study, 25-OHD serum concentrations among the psoriasis and psoriatic arthritis patients were compared. RESULT: There are more patients in the PsA group with 25-OHD levels lower than 20 ng/ml; however, this finding is insufficient to obtain statistical significance (p= 0.09). PsA and psoriasis groups had similar numbers of patients with 25-OHD levels ranging from 20 to 30 mg/mL and those higher than 30 mg/mL (p> 0.05). CONCLUSION: The literature does not show significant differences between the PS and PsA groups in terms of serum 25-OHD levels and a prevalence of Vitamin D deficiency. Besides, PASI scores were higher in the PS group. CRP values in the PsA group were higher than in the PS group. There was a poor negative correlation between CRP and serum 25-OHD levels in the PsA group. This correlation was not found in the PS group.
