A genome-wide meta-analysis of palmoplantar pustulosis implicates TH2 responses and cigarette smoking in disease pathogenesis

\ua9 2024 The AuthorsBackground: Palmoplantar pustulosis (PPP) is an inflammatory skin disorder that mostly affects smokers and manifests with painful pustular eruptions on the palms and soles. Although the disease can present with concurrent plaque psoriasis, TNF and IL-17/IL-23 inhibitors show limited efficacy. There is therefore a pressing need to uncover PPP disease drivers and therapeutic targets. Objectives: We sought to identify genetic determinants of PPP and investigate whether cigarette smoking contributes to disease pathogenesis. Methods: We performed a genome-wide association meta-analysis of 3 North-European cohorts (n = 1,456 PPP cases and 402,050 controls). We then used the scGWAS program to investigate the cell-type specificity of the association signals. We also undertook genetic correlation analyses to examine the similarities between PPP and other immune-mediated diseases. Finally, we applied Mendelian randomization to analyze the causal relationship between cigarette smoking and PPP. Results: We found that PPP is not associated with the main genetic determinants of plaque psoriasis. Conversely, we identified genome-wide significant associations with the FCGR3A/FCGR3B and CCHCR1 loci. We also observed 13 suggestive (P < 5 7 10−6) susceptibility regions, including the IL4/IL13 interval. Accordingly, we demonstrated a significant genetic correlation between PPP and TH2-mediated diseases such as atopic dermatitis and ulcerative colitis. We also found that genes mapping to PPP-associated intervals were preferentially expressed in dendritic cells and often implicated in T-cell activation pathways. Finally, we undertook a Mendelian randomization analysis, which supported a causal role of cigarette smoking in PPP. Conclusions: The first genome-wide association study of PPP points to a pathogenic role for deregulated TH2 responses and cigarette smoking

Pattern recognition receptors in immune disorders affecting the skin.

Contains fulltext : 109004.pdf (publisher's version ) (Open Access)Pattern recognition receptors (PRRs) evolved to protect organisms against pathogens, but excessive signaling can induce immune responses that are harmful to the host. Putative PRR dysfunction is associated with numerous immune disorders that affect the skin, such as systemic lupus erythematosus, cryopyrin-associated periodic syndrome, and primary inflammatory skin diseases including psoriasis and atopic dermatitis. As yet, the evidence is often confined to genetic association studies without additional proof of a causal relationship. However, insight into the role of PRRs in the pathophysiology of some disorders has already resulted in new therapeutic approaches based on immunomodulation of PRRs

Anakinra for palmoplantar pustulosis: results from a randomized, double-blind, multicentre, two staged, adaptive placebo controlled trial (APRICOT)

Background Palmoplantar pustulosis (PPP) is a rare, debilitating, chronic inflammatory skin disease affecting the hands and feet. Clinical, immunological and genetic findings suggest a pathogenic role for interleukin (IL)-1. Objective To determine whether anakinra (an IL-1 receptor antagonist) delivers therapeutic benefit for PPP. Methods A randomised (1:1), double-blind, two-staged, adaptive, UK multi-centre, placebo-controlled trial. Participants had a diagnosis of PPP (>6 months) requiring systemic therapy. Treatment was eight weeks of anakinra or placebo via daily self-administered subcutaneous injections. The primary outcome was the Palmoplantar Pustulosis Psoriasis Area and Severity Index (PPPASI) at 8 weeks. Results A total of 374 patients were screened and 64 were enrolled (31 anakinra, 33 placebo) with mean baseline PPPASI 17.8 (SD=10.5); PPP investigator’s global assessment severe (50%) or moderate (50%). The baseline adjusted mean difference in PPPASI favoured anakinra but did not demonstrate superiority in intention-to-treat analysis, -1.65, 95% CI [-4.77 to 1.47], p=0.300. Secondary objective measures including fresh pustule count (2.94, 95% CI [-26.44 to 32.33] favouring anakinra), total pustule count (-30.08, 95% CI [-83.20 to 23.05] favouring placebo), and patient-reported outcomes, similarly did not show superiority of anakinra. When modelling the impact of adherence, the PPPASI complier average causal effect (CACE) for an individual who receives ≥90% total treatment (48% anakinra group), was -3.80, 95% CI [-10.76 to 3.16], p=0.285. No serious adverse events occurred. Conclusions No evidence for superiority of anakinra was found. IL-1 blockade is not a useful intervention for the treatment of PPP

A prospective observational cohort study comparing the treatment effectiveness and safety of ciclosporin, dupilumab and methotrexate in adult and paediatric patients with atopic dermatitis: results from the UK-Irish A-STAR register

Background The main conventional systemic atopic dermatitis (AD) treatments are methotrexate (MTX) and ciclosporin (CyA). Dupilumab was the first novel systemic agent to enter routine clinical practice. There are no head-to-head randomised controlled trials or real-world studies comparing these agents directly. Network meta-analyses provide indirect comparative efficacy and safety data and have shown strong evidence for dupilumab and CyA. Objectives The aim of this study was to compare the real-world clinical effectiveness and safety of CyA, dupilumab and MTX in AD. Methods We compared the effectiveness and safety of these systemic agents in a prospective observational cohort study of adult and paediatric patients recruited into the UK-Irish Atopic eczema Systemic TherApy Register (A-STAR). Treatment effectiveness measures included Eczema Area and Severity Index (EASI), Patient-Oriented Eczema Measure (POEM), Peak Pruritus Numerical Rating Scale (PP-NRS), Dermatology Life Quality Index (DLQI) and children’s DLQI (cDLQI). Minimum duration of treatment was 28 days and follow-up was 12 months. Adjusted Cox-regression was used to compare the hazards of achieving EASI-50, EASI-75 and EASI-90 over time, and linear mixed-effects models were used to estimate changes in efficacy scores. Treatment safety was assessed by examining adverse events (AEs) at follow-up visits. Results 488 patients (n=311 adults and n=177 children/adolescents) on dupilumab (n=282), methotrexate (n=149), or CyA (n=57) were included. CyA and MTX were primarily used first line, while dupilumab was mainly a second line systemic as per UK National Institute of Clinical and Care Excellence (NICE) recommendations. EASI-50, EASI-75 and EASI-90 were achieved more rapidly in the dupilumab and CyA groups compared to MTX. After adjustment for previous severity, the reduction in EASI, POEM, PP-NRS and DLQI was greater for patients treated with dupilumab compared to MTX. In severe patients the reduction in EASI, POEM, and PP-NRS was even greater with CyA. The incidence of AEs was similar across groups (734, 654 and 594 per 10,000 person-month on CyA, dupilumab and MTX respectively). Conclusions This real-world comparison of CyA, dupilumab and MTX in AD suggests that dupilumab is consistently more effective than MTX and that CyA is most effective in very severe disease within one follow-up year

Cutaneous abnormalities in rheumatoid arthritis compared with non‐inflammatory rheumatic conditions

BACKGROUND: Cutaneous abnormalities are common in rheumatoid arthritis, but exact prevalence estimates are yet to be established. Some abnormalities may be independent and coincidental, whereas others may relate to rheumatoid arthritis or its treatment. OBJECTIVES: To determine the exact nature and point prevalence of cutaneous abnormalities in patients with rheumatoid arthritis compared with those in patients with non‐inflammatory rheumatic disease. METHODS: 349 consecutive outpatients for rheumatology (205 with rheumatoid arthritis and 144 with non‐inflammatory rheumatic conditions) were examined for skin and nail signs by a dermatologist. Histories of rheumatology, dermatology, drugs and allergy were noted in detail. RESULTS: Skin abnormalities were reported by more patients with rheumatoid arthritis (61%) than non‐inflammatory controls (47%). More patients with rheumatoid arthritis (39%) than controls (10%) attributed their skin abnormality to drugs. Cutaneous abnormalities observed by the dermatologist were also more common in patients with rheumatoid arthritis (76%) than in the group with non‐inflammatory disease (60%). Specifically, bruising, athlete's foot, scars, rheumatoid nodules and vasculitic lesions were more common in patients with rheumatoid arthritis than in controls. The presence of bruising was predicted only by current steroid use. The presence of any other specific cutaneous abnormalities was not predicted by any of the variables assessed. In the whole group, current steroid use and having rheumatoid arthritis were the only important predictors of having any cutaneous abnormality. CONCLUSIONS: Self‐reported and observed cutaneous abnormalities are more common in patients with rheumatoid arthritis than in controls with non‐inflammatory disease. These include cutaneous abnormalities related to side effects of drugs or to rheumatoid arthritis itself and other abnormalities previously believed to be independent but which may be of clinical importance