Atypical and Typical Presentation of Erythema Nodosum: Clinical Differences in Treatment and Outcome.

INTRODUCTION: Erythema nodosum (EN) is the most common form of panniculitis that predominantly affects the shins. While EN in atypical sites has been described by many authors, there are currently only case studies published on this topic. This study aimed to evaluate clinical differences between patients suffering from EN on the shins, compared to patients with EN in atypical locations. METHODS: We analyzed 105 patients in a retrospective, single-center study at a university hospital in Switzerland. Typical EN was defined as lesions, found only on the lower legs, while atypical EN as lesions on the upper legs, trunk, arms, or face, only or in addition to lesions on the lower legs. The patients were assessed for age, gender, dermatologic history, time until first medical consultation, time to diagnosis, and time until remission. Further, etiology, symptoms, and applied therapies were investigated. Findings were then compared between the typical and atypical EN cohorts. RESULTS: Overall, we included 70 patients (37.99 ± 15.67 [3-81] years) with EN solely on the shins and 35 patients (41.27 ± 16.85 [9-76] years) with EN on other locations. Interestingly, time until diagnosis was significantly shorter in atypical EN (p = 0.034, 1.14 ± 4.68 vs. 0.46 ± 1.14 months). Time to remission was similar in both groups (3.61 ± 2.73 vs. 3.05 ± 2.86 months, respectively). Sarcoidosis was the only etiologic factor significantly more frequent in atypical EN compared to typical EN (23% vs. 9%, p = 0.042). Besides that, solely subtle differences were seen regarding etiology, gender, age at onset, course of the disease, and symptoms. CONCLUSIONS: Our study suggests that only minor alterations between both study populations exist. Significant differences were found in time to diagnosis (shorter for atypical EN), as well as in sarcoidosis as an etiologic factor (more frequent in atypical EN). While adalimumab was only prescribed in atypical EN cases, prognosis seems to be similar for typical and atypical EN (similar time to remission, similar amount of reoccurring cases). Due to the limited sample size, however, our study population may have been too small to detect the relevant differences, and bigger studies may be needed.

Saliency-Enhanced Content-Based Image Retrieval for Diagnosis Support in Dermatology Consultation: Reader Study.

BACKGROUND: Previous research studies have demonstrated that medical content image retrieval can play an important role by assisting dermatologists in skin lesion diagnosis. However, current state-of-the-art approaches have not been adopted in routine consultation, partly due to the lack of interpretability limiting trust by clinical users. OBJECTIVE: This study developed a new image retrieval architecture for polarized or dermoscopic imaging guided by interpretable saliency maps. This approach provides better feature extraction, leading to better quantitative retrieval performance as well as providing interpretability for an eventual real-world implementation. METHODS: Content-based image retrieval (CBIR) algorithms rely on the comparison of image features embedded by convolutional neural network (CNN) against a labeled data set. Saliency maps are computer vision-interpretable methods that highlight the most relevant regions for the prediction made by a neural network. By introducing a fine-tuning stage that includes saliency maps to guide feature extraction, the accuracy of image retrieval is optimized. We refer to this approach as saliency-enhanced CBIR (SE-CBIR). A reader study was designed at the University Hospital Zurich Dermatology Clinic to evaluate SE-CBIR's retrieval accuracy as well as the impact of the participant's confidence on the diagnosis. RESULTS: SE-CBIR improved the retrieval accuracy by 7% (77% vs 84%) when doing single-lesion retrieval against traditional CBIR. The reader study showed an overall increase in classification accuracy of 22% (62% vs 84%) when the participant is provided with SE-CBIR retrieved images. In addition, the overall confidence in the lesion's diagnosis increased by 24%. Finally, the use of SE-CBIR as a support tool helped the participants reduce the number of nonmelanoma lesions previously diagnosed as melanoma (overdiagnosis) by 53%. CONCLUSIONS: SE-CBIR presents better retrieval accuracy compared to traditional CBIR CNN-based approaches. Furthermore, we have shown how these support tools can help dermatologists and residents improve diagnosis accuracy and confidence. Additionally, by introducing interpretable methods, we should expect increased acceptance and use of these tools in routine consultation.

Clock-like Mutation Signature May Be Prognostic for Worse Survival Than Signatures of UV Damage in Cutaneous Melanoma.

Novel treatment modalities comprising immune checkpoint inhibitors and targeted therapies have revolutionized treatment of metastatic melanoma. Still, some patients suffer from rapid progression and decease within months after a diagnosis of stage IV melanoma. We aimed to assess whether genomic alterations may predict survival after the development of stage IV disease, irrespective of received therapy. We analyzed tumor samples of 79 patients with stage IV melanoma using a custom next-generation gene-sequencing panel, MelArray, designed to detect alterations in 190 melanoma-relevant genes. We classified the patients: first, as short survivors (survival ≤6 months after stage IV disease, n = 22) and long survivors (survival >6 months, n = 57); second, by using a cut-off of one year; and third, by comparing the longest surviving 20 patients to the shortest surviving 20. Among analyzed genes, no individual gene alterations, or combinations of alterations, could be dichotomously associated with survival. However, the cohort's mutational profiles closely matched three known mutational signatures curated by the Catalog of Somatic Mutations in Cancer (COSMIC): UV signature COSMIC_7 (cosine-similarity 0.932), clock-like signature COSMIC_5 (cosine-similarity 0.829), and COSMIC_30 (cosine-similarity 0.726). Patients with UV signature had longer survival compared to patients with clock-like and COSMIC 30 (p < 0.0001). Subgroup dichotomization at 6 months showed that 75% of patients with UV signature survived longer than 6 months, and about 75% of patients with clock-like signature survived less than 6 months after development of stage IV disease. In our cohort, clock-like COSMIC_5 mutational signature predicted poor survival while a UV signature COSMIC_7 predicted longer survival. The prognostic value of mutational signatures should be evaluated in prospective studies.

Access to psoriasis treatment in Brazil and Chile: A cross-sectional multicentre Global Healthcare Study on Psoriasis.

BACKGROUND: Sufficient data on access to systemic treatment for patients with psoriasis living in Latin America (LA) including Brazil and Chile are lacking. Understanding the availability and limiting factors of access to treatments can help to improve patient care and decrease long-term healthcare costs. OBJECTIVES: In association with the Global Psoriasis Atlas, this cross-sectional survey study analysed the availability and insurance reimbursement of systemic treatments for adult patients with psoriasis in Brazil and Chile. METHODS: A multicentre, cross-sectional Global Healthcare Study on Psoriasis was performed in Brazil and Chile in 2020. For each eligible adult patient with psoriasis, doctors and nurses completed a 48-item questionnaire about clinical aspects of psoriasis including the Psoriasis Area Severity Index (PASI), body surface area (BSA) score and the Dermatology Life Quality Index (DLQI), as well as the availability of systemic treatments and insurance reimbursement status. Between-country differences were compared with Wilcoxon rank sum tests for continuous variables, and a χ2-test or Fisher's exact test, where appropriate, for categorical variables. The median and interquartile range (IQR) was calculated for non-normal distributed data. RESULTS: A total of 1424 patients with psoriasis from 43 centres [27 centres in Brazil (n = 826) and 16 in Chile (n = 598)], were included with a mean (SD) age of 49.1 (16.3) and 49.2 (15.1) years, respectively. Unstratified analyses revealed that patients with psoriasis in Chile had more severe disease than those in Brazil [PASI 11.6 vs. 8.4 (P < 0.001) and BSA 14.7 vs. 12.0 (P = 0.003), respectively]. For patients with moderate-to-severe psoriasis, defined as PASI and/or BSA ≥ 10, systemic nonbiologic drugs were available (81.2% in Brazil and 65.3% in Chile, P ≤ 0.001), but only 37.0% of patients in Brazil and 27.3% in Chile received biologics (P = 0.01). Lack of availability and/or lack of insurance reimbursement for biologic drugs for patients with moderate-to-severe psoriasis was reported for 22.2% (50 of 225) in Brazil and 67.9% (148 of 218) in Chile (P < 0.001). Patients with no access to biologic therapies due to lack of availability/insurance reimbursement had a median PASI of 9.15 (IQR 3.00-14.25) in Brazil and 12.0 (IQR 5.00-19.00) in Chile (P = 0.007), as well as a median BSA of 7.0 (IQR 3.00-15.00) and 12.0 (IQR 5.00-22.50) (P = 0.002), and median DLQI of 11.0 (6.00-15.00) and 21.0 (6.50-25.00) (P = 0.007), respectively. CONCLUSIONS: Chilean patients had significantly more severe psoriasis compared with Brazilian patients in our study. While nonbiologic treatments for moderate-to-severe psoriasis were available in both LA countries, there is a high need for improvement in access to more effective psoriasis treatments including biologics. Our results highlight a significant gap between treatment recommendations in international psoriasis guidelines and real-world situations in Brazil and Chile.

HLA-B27 as a predictor of effectiveness of treatment with TNF inhibitors in axial spondyloarthritis: data from the Swiss Clinical Quality Management Registry.

OBJECTIVE: To explore the impact of the human leucocyte antigen (HLA)-B27 on the effectiveness of tumor necrosis factor inhibitors (TNFi) in patients with axial spondyloarthritis (axSpA). METHODS: A total of 1109 patients with available HLA-B27 status (831 B27+ patients and 278 B27- patients) fulfilling the Assessment of Spondyloarthritis international Society classification criteria for axSpA from the prospective Swiss Clinical Quality Management Registry initiating a first TNFi were included. Drug retention was investigated with multiple adjusted Cox proportional hazard models with imputation of missing values. Multiple-adjusted logistic regression analyses were used to assess the proportion of patients reaching 50% reduction in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50) at 1 year. RESULTS: B27+ and B27- patients differed with regard to age, sex, BASDAI, C-reactive protein (CRP), body mass index, enthesitis, uveitis, and classification status. After adjustment for potential confounders for the relationship between HLA-B27 and drug effectiveness (sex and family history of spondyloarthritis), a higher risk of drug discontinuation was found in B27- patients (HR 1.53, 95% CI 1.27-1.83). This difference decreased after additional adjustment for parameters which may act as mediators (HR 1.30, 95% CI 1.30-1.55). Male sex and elevated C-reactive protein (CRP) levels were consistently associated with longer retention. Comparable results were obtained for BASDAI50 responses. CONCLUSION: The HLA-B27 genotype is an important predictor of treatment effectiveness. Male sex and CRP seem, however, to better describe variability of response in individual patients. This data may help avoiding potential discrimination of B27- individuals with regard to TNFi initiation. Key Points • HLA-B27 is a predictor of effectiveness of TNF inhibitors in axial spondyloarthritis. • Variability of response in individual patients is better defined by sex and objective markers of disease activity, such as C-reactive protein.