Introduction Psoriatic arthritis (PsA) is a chronic immune-mediated inflammatory spondyloarthropathy associated with psoriasis. PsA is frequently associated with metabolic disorders including, obesity, metabolic syndrome, and diabetes mellitus (DM). Type 2 DM is among the most common metabolic disorders, with a prevalence ranging from 2.4 to 14.8% in the general population. Methods We conducted a narrative review of the English-language studies from January 1989 to September 2019 investigating the risk of type 2 DM in patients with PsA, the pathogenic mechanism linking DM to PsA, and the effects on insulin sensitivity exerted by systemic therapies for PsA. Results The prevalence of type 2 DM in patients with PsA ranges from 6.1 to 20.2%, generally higher when compared to the general population. The higher risk of DM is reported in women with more severe forms of PsA. Elevated serum levels of adipokines, including TNF-α, which inhibits the autophosphorylation of the insulin receptor and suppresses the expression of glucose transporter 4, favor insulin resistance and could partially explain the association between PsA and DM. Moreover, adiponectin and omentin, with insulin-sensitizing and anti-atherogenic properties, are decreased in patients with PsA. Some of the treatments for PsA could affect the glucose homeostasis. Systemic corticosteroids are known to impair insulin resistance, whereas apremilast (phosphodiesterase type 4 inhibitor) and TNF-α inhibitors could exert neutral effect or reduce the insulin-resistance. The role of IL-17 or IL-23 inhibitors has been marginally investigated. Conclusions Patients affected by PsA have a higher prevalence of type 2 DM compared with the general population. The mechanism linking PsA with DM has not been completely clarified, but some of the principal mediators could be TNF-α and adipokine, especially adiponectin and omentin. Apremilast and TNF-α inhibitor may have a favorable effect and could be safely used in patients with DM.

Dupilumab showed significant improvement of adolescent atopic dermatitis (AD) signs and symptoms in clinical trials, with a good safety profile. Herein we report the real-word effectiveness and safety of dupilumab in adolescents with moderate to severe AD from January to October 2020, during the COVID-19 pandemic in Italy. All patients had a diagnosis of AD for a mean [SD] 12.8 [3.1] years. Baseline demographics, AD characteristics (EASI, cDLQI, NRS itch score, NRS sleep loss score) at baseline and week 16, and safety data were collected. Nineteen patients (52.6% men; mean [SD] age, 15.6 [1.4] years [range, 13–17 years]) were included in the analysis. All patients reached EASI-50 and 78.9% EASI-75, especially in those with EASI≥30 and BMI < 25 at baseline, with marked reduction for cDLQI (77.4%), NRS itch score (5.9 point), and NRS sleep loss score (87.5%). One patient contracted asymptomatic SARS-CoV-2 infection and 1 developed mild conjuntivitis, without stopping dupilumab. In this real-word experience the effectiveness of dupilumab was excellent and resulted higher than that observed in clinical trials, with a good safety profile during COVID-19 pandemic.