The Conundrum of Psoriatic Arthritis: a Pathogenetic and Clinical Pattern at the Midpoint of Autoinflammation and Autoimmunity

Understanding the interplay between psoriatic arthritis and gout: "Psout"

The interplay between Psoriatic arthritis and Gout is a current diagnostic challenge faced by many physicians and researchers. We aimed at reviewing the coexistence of gout and its features such as hyperuricemia and deposition of monosodium urate crystals in patients with psoriatic arthritis (PsA). We also focused on a brief presentation of the pathophysiology underneath the interplay between PsA and gout, and ultimately on recommendation of approaches for the differential diagnosis. The literature search for this narrative review was conducted using PubMed and Medline and after retrieving and screening the references, articles were selected according to the inclusion and exclusion criteria. Part of the assessed studies reported the coexistence of PsA and gout (Psout) and its association with several clinical outcomes among affected patients. Other studies stressed incidences of misdiagnosis of gout with PsA and vice versa. Additionally, the presence of hyperuricemia in PsA patients could interfere with the patient's characteristics and outcomes of their treatment. Further research on the assessment and clinical course of Psout is required to develop an official protocol for its diagnosis and treatment.

Distinct innate and adaptive immunity phenotypic profile at the circulating single-cell level in Psoriatic Arthritis

Mass cytometry was employed to investigate 47 circulating leukocyte subsets in patients with active psoriatic arthritis (PsA, n = 16) compared to healthy controls (n = 13), seropositive (RF and/or anti-CCP, n = 12) and seronegative (n = 9) RA patients. Comparing PsA to controls, different cell frequencies were found in both innate and adaptive immunity cell subsets, as well as in cells bridging innate and adaptive immunity. In some T-cell subsets increased costimulatory molecules' expression in PsA, was also noted..No changes were observed in patients who remained disease-active after 3 months of treatment, in contrast to those who achieved remission/low-disease activity. Comparing PsA to seropositive RA, elevated frequencies of naïve and activated CD8⁺ T-cells, B-cells, MAIT/iNKT and ILCs were found, while the opposite was the case for terminal effector, senescent, and Th2-like-cells. Strikingly, the composition of the leukocyte pool in PsA was comparable to seronegative RA, providing evidence for the pathogenetic similarities between these two entities.

Exploring comorbidity and pharmacological treatment patterns in psoriasis - a retrospective population-based cross-sectional study

Background

Individuals with psoriasis face an increased risk of suffering from various comorbid conditions. However, there haven´t been any studies conducted in Sweden to examine the frequency of comorbidities and the corresponding treatment for these conditions among psoriasis patients.

Methods

The Cosmic electronic medical record represents a comprehensive repository of medical information including all residents of Region Jönköping. To conduct a population-based retrospective cross-sectional study, all individuals diagnosed with psoriasis between April 9, 2008 and July 1, 2016, were identified via the electronic medical records using ICD-10 codes. Data on comorbidity and dispensation of prescribed drugs against these comorbid conditions were analyzed.

Results

During the study period, 1.7% of the population (4,587 individuals) were diagnosed with psoriasis, with 74.3% of cases classified as mild to moderate psoriasis and 25.7% as severe. The remaining 268,949 individuals did not receive a psoriasis diagnosis. The study showed that psoriasis patients had higher odds of experiencing the majority of the comorbid conditions examined. Arthritis other than psoriasis arthritis was found to be the most prevalent comorbid diagnosis among psoriasis patients (adjusted OR 7.2, CI 95% 6.4-8.2, p < 0.001), followed by obesity (OR 2.4, CI 95% 1.9-3.1, p < 0,001). There was no significant difference in drug prescription for comorbid diseases between patients with psoriasis and patients without psoriasis except for arthritis and smoking cessation treatment.

Conclusions

Individuals with psoriasis are more susceptible to experiencing multiple comorbid conditions compared to the general population, particularly those with severe psoriasis. There is no evidence of undertreatment of comorbidity except for arthritis among psoriasis patients.

What's new and what's next for biological and targeted synthetic treatments in psoriatic arthritis?

INTRODUCTION

Psoriatic arthritis (PsA) is a chronic arthritis typically associated with cutaneous psoriasis (PsO). Its pathogenesis is connected to an innate and acquired immune response, as well as genetic risk alleles. The extent of immunopathogenic mechanisms and the heterogenicity of clinical manifestation make the identification of patient-targeted therapies a critical issue, and the treatment decision challenging in patients' management.

AREAS COVERED

This review includes a brief overview of biological and small-molecule therapies, focusing on evidence from clinical trials and real-world data that support their use in PsA. We summarize novel and future possible therapeutic strategies, the importance that comorbidities have on selection of therapy and discuss the adverse event of each drug. Relevant papers for up to 1 August 2022 (trials, real-life studies, and reviews) regarding biologics and/or small molecules were summarized.

EXPERT OPINION

In recent years, the treatment of PsA has been revolutionized by new targeted therapies, which offer the opportunity to perform a tailored-tail management, considering risk factors, comorbidities, and the different PsA phenotypes. Growing experience with these new agents allows novel treatment approaches that may improve clinical outcomes for PsA patients, in terms of remission/low disease activity and quality of life.

D-Mannose Suppresses γδ T Cells and Alleviates Murine Psoriasis

Psoriasis is a chronic skin disorder associated with multiple sequelae, such as psoriatic arthritis and cardiovascular diseases. Increasing evidence has shown that γδ T cells, as sources of IL-17A, play critical roles in psoriatic inflammations. However, there still lack effective ways to manipulate these pathogenic γδ T cells, which are less well studied than αβ T cells. The present study aims to characterize the phenotype of γδ T cells and evaluate the impact of D-mannose (a C-2 epimer of glucose) on γδ T cell-mediated psoriasis. We found that skin-draining LN γδ T cells underwent robust proliferation and acquired an IL-17-producing phenotype during psoriasis. The transcriptomic profiles of these psoriatic γδ T cells had elevated glycolytic signatures. Importantly, D-mannose treatment suppressed the γδ T cell reaction and successfully alleviated the local and systematic inflammation induced by imiquimod. The decreased AKT/mTOR/HIF-1α signaling and glycolytic ability may contribute to the suppression of γδ T cells achieved by D-mannose. Our study increased understanding of γδ T cells in psoriasis and promoted D-mannose utilization as a potential clinical application for autoimmune diseases driven by γδ T cells.