Transcriptome Meta-Analysis Confirms the Hidradenitis Suppurativa Pathogenic Triad: Upregulated Inflammation, Altered Epithelial Organization, and Dysregulated Metabolic Signaling

Hidradenitis suppurativa (HS) is an inflammatory skin condition clinically characterized by recurrent painful deep-seated nodules, abscesses, and sinus tracks in areas bearing apocrine glands, such as axillae, breasts, groins, and buttocks. Despite many recent advances, the pathophysiological landscape of HS still demands further clarification. To elucidate HS pathogenesis, we performed a meta-analysis, set analysis, and a variant calling on selected RNA-Sequencing (RNA-Seq) studies on HS skin. Our findings corroborate the HS triad composed of upregulated inflammation, altered epithelial differentiation, and dysregulated metabolism signaling. Upregulation of specific genes, such as KRT6, KRT16, serpin-family genes, and SPRR3 confirms the early involvement of hair follicles and the impairment of barrier function in HS lesioned skin. In addition, our results suggest that adipokines could be regarded as biomarkers of HS and metabolic-related disorders. Finally, the RNA-Seq variant calling identified several mutations in HS patients, suggesting potential new HS-related genes associated with the sporadic form of this disease. Overall, this study provides insights into the molecular pathways involved in HS and identifies potential HS-related biomarkers.

Cumulative Inflammation and HbA1c Levels Correlate with Increased Intima-Media Thickness in Patients with Severe Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease that has been associated with a greater risk of metabolic and cardiovascular comorbidities. The aim of this study is to assess cardiovascular risk by means of intima-media thickness (IMT), metabolic syndrome, and other potential biomarkers in patients with severe hidradenitis suppurativa who are candidates for biologic therapy and to explore potentially associated factors. A cross-sectional study was performed. Body mass index (BMI), carotid intima-media thickness (IMT), and blood tests, including glycemic and lipid profile, insulin, vitamin D, and inflammation markers were performed. Fifty patients were included in the study; the male/female ratio was 3:2. The mean age was 38 years, and the mean disease duration was 21.8 years. The mean carotid IMT was 651.39 μm. A positive association of IMT with disease duration, tobacco consumption, and HbA1c levels was observed. HbA1c correlated with the age of onset, hypertension, metabolic syndrome, and glucose levels. Vitamin D levels inversely correlated with the number of areas affected. In conclusion, patients with severe HS present a higher cardiovascular risk, but it is not distributed equally within the patients: Tobacco consumption, inadequate glycemic control, and disease duration could be useful clinical and biochemical markers to identify patients at higher risk.

Hidradenitis suppurativa and diabetes mellitus: updated systematic review and adjusted meta-analysis

BACKGROUND

Hidradenitis suppurativa (HS) is a debilitating and distressing chronic inflammatory skin disease. There is also evolving evidence supporting the association between HS and cardiovascular risk factors, including smoking, obesity, hyperlipidaemia and metabolic syndrome. Notably, these are clinical features and risk factors that are closely associated with type 2 diabetes mellitus (DM).

AIMS

We performed a pooled adjusted meta-analysis of comparative studies to investigate the relationship between HS and DM.

METHODS

A systematic review and meta-analysis was performed according to recommended Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. OR was used as the summary effect size.

RESULTS

From pooled analysis of unadjusted data from 12 studies, we found a significantly higher proportion of DM in HS cases compared with non-HS healthy controls (16.1% vs. 15.7%; OR = 2.17; 95% CI 1.85-2.55; P < 0.001). Adjusted effect sizes from five studies were also pooled. A significantly higher proportion of DM was found for HS compared with healthy controls, although the effect size was attenuated compared with unadjusted analyses (OR 1.69; 95% CI 1.50-1.91; P < 0.001).

CONCLUSIONS

To our knowledge, our systematic review and meta-analysis is the first to pool adjusted effect sizes. We found that HS was associated with a 1.69-fold increased odds of diabetes; however, the absolute risk difference was small (16.1% vs. 15.7%) and is probably not clinically relevant. Treating clinicians should be aware of this association, but there may not be an urgent need to perform screening for impaired glucose tolerance or diabetes.

H.E.L.P apheresis exerts long term effects on the capacity of circulating proangiogenic cells

BACKGROUND

Severe forms of mono- and polygenetic hypercholesterolemia as well as elevated Lipoprotein (a) (LP(a)) with progressing cardiovascular (CV) disease are indication for lipoprotein apheresis (LA) in Germany. Many studies investigated pleiotropic effects of LA that might contribute to beneficial effects in advanced atherosclerosis. The present study aimed at investigating the potential role of Proangiogenic Cells (PAC) in patients with new onset or chronic LA using the heparin induced extracorporeal LDL-precipitation (H.E.L.P.) apheresis system.

METHODS

Patients (n = 10) new to LA and HELP treatment were investigated immediately before, shortly after, 24 h later and 4 weeks following LA. Peripheral blood was used to count PAC in circulation via flow cytometry. In a second step, blood cells from patients were cultured in endothelial selective medium and further evaluated for adhesion in fibronectin coated chamber slides and migratory capacity (stromal cell-derived factor-1 (SDF-1) induced migration).

RESULTS

Cells expressing typical EPC markers were rarely detected in blood samples. No differences occurred over time in CD34⁺; CD34⁺ CD133⁺ CD45^-; CD34⁺/KDR⁺ and CXCR4⁺/CD14⁺ positive PAC. We found no differences in cell adhesion at the different time points, while significantly more cells migrated into the SDF-1 medium following four weeks of continuing apheresis therapy.

CONCLUSION

Using well established systems, this study was not able to demonstrate relevant acute effects of LA on PAC in patients new to LA. The increased migratory capacity of PAC might be an indicator of chronic beneficial pleiotropic effects in patients undergoing H.E.L.P. apheresis.

Increased interleukin (IL)-17 serum levels in patients with hidradenitis suppurativa: Implications for treatment with anti-IL-17 agents

BACKGROUND

Biologics seem to offer a promising nonsurgical approach in hidradenitis suppurativa (HS), especially in disease with highly pronounced inflammation. Recent studies revealed increased expression of a broad range of cytokines in lesional HS skin, including interleukin (IL)-17.

OBJECTIVE

This study was undertaken to determine IL-17 serum levels in this group of patients.

METHODS

Our study was conducted on a group of 86 patients between 16 and 72 years of age with HS. A total of 86 matched healthy volunteers constituted the control group. Enzyme-linked immunosorbent assay kits were used to quantify IL-17 serum concentration.

RESULTS

The mean IL-17 serum level of patients with HS was 3.68 ± 2.08 pg/mL, which was significantly elevated (P < .0001) compared with that found in healthy volunteers (2.5 ± 1.11 pg/mL). Moreover, there was a tendency toward higher serum concentrations of IL-17 in patients with more advanced disease (P = .005). Disease duration; patient sex, age, and body mass index; and smoking habits were not determining factors for IL-17 serum concentration.

LIMITATIONS

Hospital-based study population was a limitation, as was a lack of posttreatment assessment.

CONCLUSION

In light of our findings and literature on increased expression of IL-17 in HS lesions, evaluating the clinical effectiveness of using anti-IL-17 agents in the treatment of patients with HS is justified.

[New populations at increased cardiovascular risk: Cardiovascular disease in dermatological diseases]

The increased cardiovascular risk in some dermatological diseases has been demonstrated in recent decades. Diseases such as psoriasis and systemic lupus erythematosus are currently included in the guidelines for prevention of cardiovascular disease. Other diseases such as androgenic alopecia, polycystic ovary syndrome, hidradenitis suppurativa or lichen planus have numerous studies that point to an increased risk, however, they have not been included in these guidelines. In this article we review the evidence supporting this association, in order to alert the clinician to the need for greater control in cardiovascular risk factors in these patients.