Belgian Patients of the European Registry for Hidradenitis Suppurativa (ERHS-Be): Data, Scores, and Phenotypes since 2015.

INTRODUCTION: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease, characterized by painful and recurrent lesions in apocrine gland-bearing skin areas. It is a heterogeneous disease, which makes assessment and data collection difficult. Questionnaires with detailed items, such as the Belgian European Registry for Hidradenitis Suppurativa (ERHS-Be), are useful to study HS and its associated comorbidities. The aim of this registry was to uncover new factors associated with HS and understand HS patients' clinical profiles and efficacy of treatments. MATERIAL AND METHODS: The ERHS-Be registry is based on questionnaires, with sections for sociodemographic data, medical and HS history, clinical examination, and treatment plan. It allows identification of different clinical phenotypes and automatic calculation of severity scores. RESULTS: At present, 606 patients are included in the ERHS-Be (67% women, 33% men). The mean age at the first visit is 38.5 years. Tobacco use is present in 72.6% of patients. A family history of HS is noted in 42% of patients. Comorbidities are documented in this cohort: depression is present in 43.8% of patients, arthritis in 27.8%, obesity in 31.5%, hypertension in 10.6%, diabetes mellitus in 6.4%, and dyslipidemia in 12.4%. Moreover, 7.7% of patients suffer from IBD and 27.4% have a pilonidal sinus. History of severe acne is found in 32.1% of patients and psoriasis in 9.3%. Thirteen percent of women in our cohort suffer from polycystic ovarian syndrome. Severity of disease is quantified in 533 patients: for instance, Hurley I, II, and III scores proportions are, respectively, 32.3%, 52.7%, and 15%, while the mean IHS4 score is 5.2. This registry also enables determination of relative phenotype proportions in our cohort, according to different classifications. CONCLUSION: The ERHS-Be questionnaires allow systematic and larger data collection, including detailed comorbidities, phenotypes, and severity of disease. Analysis of this large database will contribute to a better understanding and management of HS, at a time where new therapeutic options are becoming available.

Factors Associated with Severe Hidradenitis Suppurativa, Using Hurley Staging and Metascore.

INTRODUCTION: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease for which certain risk factors are well known: obesity and smoking (in particular). However, the factors associated with more severe conditions, and therefore potential aggravators of the disease, remain a matter of debate. Our study aims to determine the clinical factors associated with severe HS using several severity scores. METHODS: The data were obtained via the ERHS questionnaire from patients exclusively recruited at Erasme Hospital in Brussels. The severity of HS was firstly estimated by the Hurley score, and secondly by a metascore, a system combining the iHS4, HS-PGA, SAHS, and DLQI. Univariable and multivariable analyses were performed. RESULTS: Six hundred and forty-seven patients were included in the Hurley analysis, and 456 patients in the metascore analysis. In multivariable analysis, men have a more severe metascore than women (odds ratio [OR] = 1.89, p = 0.022), smoking was associated with a more severe disease according to metascore, especially in mild cases (OR = 0.76, p = 0.043), and an elevated body mass index was associated with having Hurley stage III disease compared to Hurley I or II disease (OR = 1.09, p = 0.001). A significant association is also shown between blood pressure and Hurley stage (OR = 0.97, p = 0.025). Self-reports of nonsteroidal anti-inflammatory drugs aggravating the disease is also a factor associated with greater severity according to the metascore (OR = 0.12, p = 0.008). Finally, several locations of HS lesions were associated with greater severity, in particular the armpits according to the metascore (OR = 0.29, p < 0.001), and the perianal area according to the Hurley score (OR = 0.15, p < 0.001). CONCLUSION: HS seems to be more severe in men; smoking seems to aggravate mild cases of HS, while increased body mass index plays a major role in the transition from Hurley II to Hurley III.

Treatment of Acne with Isotretinoin Should Be Avoided in Patients with Hidradenitis Suppurativa "Conglobata Phenotype".

BACKGROUND: Acne conglobata (AC) and nodulocystic acne have long been confused clinically, despite the presentation and the response to treatment being different. AC and hidradenitis suppurativa (HS) resemble each other; a subtype of HS called "conglobata phenotype" has recently been reported in a large Dutch cohort. Acne vulgaris and HS are often associated. Isotretinoin is typically ineffective in treating HS and may even aggravate it, but it is often indispensable in treating acne vulgaris. OBJECTIVE: The aim of the study was to assess whether isotretinoin may be used safely in adults with both HS and acne vulgaris and when it might be contraindicated. MATERIALS AND METHODS: Belgian HS patients from the European Registry for Hidradenitis Suppurativa Registry (ERHS) reporting a history of severe acne of the face and/or the back, and who have ever used isotretinoin for their acne, were all selected. Patients whose acne worsened on isotretinoin were compared to patients whose acne did not worsen (improvement or no change). RESULTS: Among the 82 selected patients, 10 (12.2%) report that their acne was aggravated while taking isotretinoin, while 72 (87.8%) report that their acne was not aggravated on isotretinoin. Of the 10 HS patients whose acne worsened with isotretinoin, 9 (90%) were men (p = 0.04) and 8 (80%) were HS "conglobata phenotype" (p < 0.001). In contrast, 47 (65.3%) of the 72 patients whose acne did not worsen on isotretinoin belonged to the HS "regular phenotype" (p = 0.01). On multivariate analysis, the item most strongly associated with poor response to isotretinoin was the HS "conglobata phenotype," followed by body mass index (BMI) (worse response to isotretinoin if BMI >25 kg/m2). Additionally, of 26 patients who received isotretinoin while their HS had already started, only 6 (23.1%) reported isotretinoin effectiveness on their HS. CONCLUSION: Subject to confirmation by larger studies, our study suggests that isotretinoin should be avoided in the treatment of acne in HS patients with the HS "conglobata phenotype," as it may worsen the acne, likewise being male or having a BMI above 25 seems to increase this risk of a bad therapeutic outcome. Patients with an HS "regular phenotype" appear to be at a reduced risk of isotretinoin treatment worsening their acne.