Genetic and Hormonal Determinations in a Pair of Identical Twins with Early Onset Psoriasis Vulgaris: Case Report and a Brief Review of the Literature

Psoriasis vulgaris is a chronic inflammatory dermatosis with major impact on patients’ life quality. The etiopathogenesis is multifactorial, depending on complex interactions between genetic and environmental factors. We present the case of two female patients, identical twins of 33 years old, suffering from psoriasis vulgaris since childhood. Patient A developed specific lesions of psoriasis at the age of 7 and patient B started to develop psoriasis lesions on the scalp two years later. At the age of 31, patient A was diagnosed with psoriatic arthritis. Laboratory test results were within the normal ranges for both patients. Hormonal and immunological determinations revealed the presence of a high level of antithyroidperoxidase antibody in patient A and increased level of prolactin in patient B. Ultrasonographic assessment of the thyroid detected the presence of bilateral micronodules in the first subject. Knowing that early onset psoriasis is associated with the presence of Human Leukocyte Antigen Cw6(HLA-Cw6), we aimed to confirm this hypothesis for our subjects. Although HLA-Cw6 is the most frequent mutation in psoriasis patients and it is present in about two-thirds of the tested subjects,the genetic results for both patients were negative, strengthening the fact that other factors, the environmental one and the hormonal disorders had an important role in their psoriasis pathogenesis. Under these conditions, we emphasize the importance of including a hormonal evaluation approach of psoriasis patients in order to diagnose and treat pathologies that may be related with disease exacerbations