Occurrence of adverse events associated with the initiation of methotrexate and biologics for the treatment of psoriasis in routine clinical practice.

Background: Limited information exists on the risk of adverse events (AEs) attributed to methotrexate (MTX) and biologics for the treatment of psoriasis/psoriatic arthritis (PsA/PsO) in heterogeneous clinical practice and beyond the duration of clinical trials.Methods: An observational study of 6294 adults with incident PsA/PsO who initiated MTX or biologics in Stockholm from 2006-2021 was conducted. The risk of kidney, liver, hematological, serious infectious, and major gastrointestinal AEs was quantified and compared between therapies using incidence rates, absolute risks, and adjusted hazard ratios (HRs) from propensity-score weighted Cox regression.Results: Median follow-up was 4.3 (2-7) years. Users of MTX had a higher risk of anemia (HR 1.79 [95% CI, 1.48-2.16]), particularly mild-moderate anemias (1.93;1.49-2.50), and mild (1.46;1.03-2.06) and moderate-severe liver AEs (2.22;1.19-4.15) compared to biologics. Chronic kidney disease incidence did not differ between therapies (affecting 1.5% of the population in 5 years; HR:1.03;0.48-2.22). Acute kidney injury, serious infections, and major gastrointestinal AEs showed low absolute risks and no clinically meaningful differences between both therapies.Conclusion: The use of MTX for psoriasis patients in routine care was associated with a higher risk of anemia and liver AEs than biologics, but similar risks of kidney, serious infections, and major gastrointestinal AEs.

IL-22 Downregulates Peptidylarginine Deiminase-1 in Human Keratinocytes: Adding Another Piece to the IL-22 Puzzle in Epidermal Barrier Formation.

Increased presence of IL-22+ cells in the skin is a characteristic finding in skin barrier defects, such as psoriasis and atopic dermatitis. However, mechanistic insight into effects of IL-22 on epidermal functioning is yet to be elucidated. One crucial step during epidermal differentiation is deimination or citrullination. Here, we show reduced levels of peptidylarginine deiminase 1, an enzyme that converts peptidylarginine into citrulline in lesional psoriatic skin. IL-22 signaling through the IL-22 receptor complex was found to suppress expression of peptidylarginine deiminase 1 in epidermal keratinocytes. Subsequently, total peptidylarginine deiminase activity and extent of protein deimination in keratinocytes treated with IL-22 were reduced together with a significant decrease in deimination of keratin 1 and FLG, both important for epidermal differentiation. Vitamin D and acitretin partly restored the peptidylarginine deiminase 1 defect caused by IL-22. Collectively, we show that IL-22 downregulates deimination, thus identifying a potential target for treatment of skin barrier defects.

Antiviral therapy in children with hydroa vacciniforme.

Hydroa vacciniforme is a rare, usually quite severe, photo-dermatosis. Association with Epstein-Barr virus infection and a possibly increased risk of lymphoproliferative malignancy have been demonstrated. We describe here four patients with Epstein-Barr virus-associated hydroa vacciniforme treated with acyclovir/valacyclovir therapy with a good clinical response. The children were reported to have less fatigue, fewer eruptions, less scarring, and increased ability to spend time outdoors without provoking new eruptions. This was also in agreement with clinical observations. However, one patient progressed into an anaplastic lymphoma kinase-1-negative anaplastic large-cell lymphoma in the upper jaw. This was preceded by an increase in EBV viral load. Acyclovir/valacyclovir therapy is a safe treatment. Further studies are required to confirm these results.