Vitiligo is a common skin disease characterized by the presence of well circumscribed, depigmented, milky white macules devoid of identifiable melanocytes. Although the detection of circulating anti-melanocytic antibodies and of infiltrating lymphocytes at the margin of lesions supports the view that vitiligo is an autoimmune disorder, its etiology remains unknown. In particular, it is still a matter of debate whether the primary pathogenic role is exerted by humoral or cellular abnormal immune responses. In this study, the presence of specific cytotoxic T lymphocyte responses against the melanocyte differentiation antigens Melan-A/MART1, tyrosinase, and gp100 in vitiligo patients have been investigated by the use of major histocompatibility complex/peptide tetramers. High frequencies of circulating melanocyte-specific CD8+ T cells were found in all vitiligo patients analyzed. These cells exerted anti-melanocytic cytotoxic activity in vitro and expressed skin-homing capacity. In one patient melanocyte-specific cells were characterized by an exceptionally high avidity for their peptide/major histocompatibility complex ligand. These findings strongly suggest a role for cellular immunity in the pathogenesis of vitiligo and impact on the common mechanisms of self tolerance.

Our study confirms that nail involvement may be overlooked in psoriasis patients. Different psoriatic patterns in the nail affect specific digits more frequently.

Hyperhomocysteinaemia represents an independent risk factor for atherosclerotic cardiovascular disease, stroke, peripheral arterial occlusive disease and venous thrombosis. Psoriasis is a chronic inflammatory skin disease associated with increased atherothrombosis and cardiovascular risk profile. The aim of this study is to investigate homocysteine, folic acid and vitamin B12 levels in a cohort of psoriatic patients and its relationship with the severity of the disease. A retrospective observational study in 98 patients with chronic plaque psoriasis and 98 healthy controls was performed. Total plasma homocysteine level, folic acid, vitamin B12 and PASI index were assessed in every patient. Patients with psoriasis had plasma homocysteine levels higher than controls (57% of cases and 25% of controls; p<0.0001). Folic acid and vitamin B12 plasma levels were lower in psoriatic patients than in controls (p = NS), lower levels of vitamin B12 were found in patients with hyperhomocysteinaemia compared to patients with a normal value of homocysteine (p = 0.0009). The severity of psoriasis assessed according to PASI (19.51+/-16.26) did not directly correlate either with higher levels of homocysteine or with vitamin B12 and folic acid plasma levels. In conclusion, a significantly higher prevalence of hyperhomocysteinaemia was found in psoriatic patients compared to healthy controls. A significant correlation between hyperhomocysteinaemia and lower vitamin B12 levels, but not folic acid, was evidenced. On the contrary, our data do not correlate the high level of homocysteine with higher PASI scores or psoriasis type, suggesting that homocysteine level can be considered an independent risk factor in psoriatic patients.

In the last years, several tyrosine kinase inhibitors (TKIs) have been developed and approved for human cancer treatment. Imatinib mesylate was the first of this novel family of drugs that target cancer-specific molecules and signalling pathways. The appearance of imatinib resistances led to the introduction of second-generation TKIs with higher potency and selectivity, such as dasatinib and nilotinib. However, the range of activity of these agents is not simply directed at tumour cells. Patients and their clinicians are indeed frequently confronted with the cutaneous side-effects associated with the employ of these drugs, which represent the most common non-hematological adverse reactions. For this reason, a systematic dermatological survey of patients receiving these therapies is highly important, and an early and appropriate dermatological treatment is required. In this review, we analyse the clinical and pathological characteristics of the most commonly reported adverse skin events associated with first- and second-generation tyrosine kinase inhibitors, with a particular emphasis on our clinical experience.