Citations

Abstract Genetic studies have significantly advanced our understanding of tauopathies, yet the genetic aetiology of Pick’s disease, a rare 3-Repeat tauopathy, remains unclear. The MAPT p.A152T variant has been identified as a risk factor for Alzheimer’s disease and progressive supranuclear palsy, but its role in Pick’s disease is unknown. In this study, we examined the prevalence of MAPT p.A152T in the largest series of neuropathologically confirmed Pick’s disease cases to date (n = 401). Through genotyping, we identified a single mutation carrier in the Pick’s disease cohort (minor allele frequency = 0.12%). We previously reported MAPT p.A152T at a 0.20% frequency in healthy controls (n = 2456), suggesting that it does not associate with 3-Repeat tauopathy risk. To further investigate the effect of the variant on MAPT transcript expression, we used bulk RNA sequencing in Alzheimer’s disease and progressive supranuclear palsy A152T mutation carriers. We did not detect significant differences in 4-Repeat tau levels, though preliminary trends may indicate more nuanced effects that need to be examined with long-read sequencing in a larger series. Overall, our study suggests that MAPT p.A152T does not increase Pick’s disease risk and may instead be linked to 4-Repeat or mixed tau pathologies, warranting further functional investigation.

ABSTRACT Background Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis highly associated with systemic comorbidities. Accurate diagnosis and treatment remain challenging due to its rarity and clinical mimickers. Objectives To evaluate demographic, clinical features and treatment outcomes in patients referred with suspected PG at a tertiary wound care centre. Methods A prospective observational study was conducted of patients referred for suspected PG between April 2021 and June 2023. Demographic, clinical and laboratory data, including biopsies and tissue cultures, were collected. Patients were categorised as having PG vs alternative diagnoses based on diagnostic criteria from Su, Maverakis and the PARACELSUS score. Results Of 60 patients (female, 51.7%; mean [SD] age 52.9 [14.0] years), 44 (73.3%) met at least one published diagnostic criterion for PG. The most common comorbidity was IBD (63.6%), followed by inflammatory arthritis (25.0%) and monoclonal gammopathy of undetermined significance (MGUS) (4.5%). Systemic corticosteroids were used by 40.9% of patients before referral, but steroid‐sparing agents and biologics were the primary treatments after consultation. Biologics and steroid‐sparing agents were associated with significant improvement in disease activity using the PGA score (average score decreased from 2.3 to 1.5, p < 0.005), with 40.9% achieving complete remission. Elevated serum inflammatory markers and faecal calprotectin were observed in PG patients but absent in non‐PG cases. Conclusions These prospective data support previously published rates of association between PG and systemic comorbidities. Steroid‐sparing anti‐neutrophilic and targeted therapies are effective steroid‐sparing strategies in managing PG. Small sample size and referral bias may limit generalisability.

Importance Accurate classification and reliability in assessment for lesions of hidradenitis suppurativa (HS) by investigators is critical to the determination of responder status and to overall data quality in clinical trials. Objective To establish consensus-based morphological definitions of HS lesions and guidance statements that standardize investigator lesion assessments for implementation in clinical trials. Evidence Review Health professionals (primarily dermatologists) with expertise in the measurement of HS disease activity as well as novice raters completed a preliminary questionnaire in which participants were asked to assess images of HS lesions and provide qualitative feedback on their decision making. Based on this feedback, detailed morphologic definitions for lesions and guidance statements that standardize lesion assessments were formulated and presented for consensus voting in 2 electronic Delphi surveys. A virtual group discussion after round 1 supported participants in round 2 voting. Findings Response rates were 84.7% (50 of 59), 86.0% (43 of 50), and 90.9% (40 of 44) in the preliminary, electronic Delphi round 1, and electronic Delphi round 2 surveys, respectively. Morphological definitions for 11 lesion types achieved the prespecified 70% consensus threshold, with 9 definitions reaching at least 90% agreement. After 2 electronic Delphi rounds, 16 of 18 guidance statements achieved the prespecified consensus threshold, with 13 statements receiving endorsement from more than 80% of participants. Two guidance statements related to assessment of tunneled plaques with multiple openings and assessment of scalp lesions failed to reach consensus. Conclusions and Relevance Common morphologic definitions and guidance that standardize assessment of HS lesions can be implemented in clinical trial protocols and investigator trainings with the goals of improving accuracy and reliability of investigator ratings.

AbstractAn increasing amount of evidence has emerged suggesting that hidradenitis suppurativa (HS) is associated with inflammatory arthritis. This study reviewed the incidence, prevalence, and predictors of inflammatory arthritis in patients with HS. A comprehensive literature search was conducted in CINAHL, Embase, and Medline from inception to February 14, 2020. Articles were included in the review if they provided data on disease epidemiology or predictors of adult or pediatric HS patients with comorbid inflammatory arthritis. There are no validated diagnostic criteria for HS, thus we considered patients as having HS if they had at least one diagnostic code in a hospital or claims database or a diagnosis of HS/inflammatory arthritis in a medical record. The same criteria were used to confirm presence of inflammatory arthritis. We identified an increased incidence of rheumatoid arthritis (RA), ankylosing spondylitis (AS), and psoriatic arthritis (PsA) in HS patients when compared with estimates in the general population. We identified a relatively high prevalence of RA, spondyloarthritis (SpA), and PsA in HS patients when compared with estimates in the general population. There was evidence to suggest that patients who are younger than 30, male, have severe HS, or are taking infliximab or adalimumab (which may also be confounded by HS disease severity) may be at greater risk for specific subtypes of inflammatory arthritis. However, further data are needed to confirm these associations. The increased incidence and prevalence of inflammatory arthritis within HS patients underscore the need for increased awareness and interdisciplinary partnership within rheumatology and dermatology.