Ultrasound as a diagnostic and management tool in hidradenitis suppurativa patients: a multicentre study

Hidradenitis Suppurativa Tunnels: Unveiling a Unique Disease Entity

Hidradenitis suppurativa tunnel structures lined with epithelium within the dermis are unique features of advanced disease stages that significantly impair patients' QOL. The presence of hidradenitis suppurativa tunnels is associated with a decreased likelihood of achieving a clinical response, even when receiving biological therapy. The cellular and molecular mechanisms underlying tunnel formation and pathology are only partially understood, which hampers the development of more effective targeted therapies. Tunnels create a unique microenvironment that drives a vicious cycle of hidradenitis suppurativa inflammation, with tunnel keratinocytes exhibiting an activated phenotype characterized by distinct gene expression signatures. In this review, we summarize the current literature and discuss aspects of the pathophysiology of tunnels, including the role of hair follicle epidermal stem cells in tunnel formation, potential role of fibroblast-mediated epithelial-mesenchymal transition, role of dermal papilla fibroblasts, and aberrant proinflammatory repair response contributing to the observed fibrosis and scarring. Finally, tunnel structures are characterized by unique microbial dysbiosis and an overabundance of Gram-negative anaerobes that are not targeted by current therapeutics. In addition to outlining the possible mechanisms of tunnel formation, we provide perspectives on the translation of current knowledge into more effective treatment approaches for patients with hidradenitis suppurativa tunnels.

Inframammary extended circumflex scapular (IMECS) flap for axillary hidradenitis suppurativa: Advantages over conventional alternatives

BACKGROUND

We presented our experience with the use of the inframammary extended circumflex scapular (IMECS) flap in the reconstruction of axillary hidradenitis suppurativa (HS). Although this flap has been described as a free flap, its use for the reconstruction of the axilla has not been documented yet.

METHODS

The study included patients with HS in the axillary region, Hurley stage III, operated between 2016 and 2020 with wide local excision and coverage with the inframammary extended circumflex scapular flap. We recorded patients' demographic details (sex, age, comorbidities, smoking habit), affected area characteristics (stage, extension, side), operative technique (simple or tunneled flap, surgical timing, hospitalization days), and postoperative outcome (time to healing, complications, recurrences, additional surgeries, and follow-up).

RESULTS

A total of 7 flaps were successfully performed in 6 patients. The mean size of the flaps was 160 cm2 (range 115-225), and the mean surgical time was 82 min (range 65-90). The flap success rate was 100%, without any partial or complete flap necrosis. There was 1 flap dehiscence and 1 additional surgery to correct a dog-ear deformity. No local recurrence was documented during follow-up. There were no complications in the donor site and no limitation to arm abduction.

CONCLUSIONS

The IMECS flap is an easy and reliable option for the reconstruction of axillary defects after excision of HS stage III hidradenitis, with low morbidity and good functional and aesthetic results.

Surgical Approach to Hidradenitis Suppurativa

Hidradenitis suppurativa is a chronic inflammatory skin condition characterized by painful nodules, abscesses, and sinus tracts that may lead to irreversible scarring complications. Therapeutic options include antibiotics, biologic therapies, and surgical procedures. Current management of hidradenitis suppurativa favors early surgical intervention along with medical therapy to promote healing and minimize scars and complications in a disease characterized by a therapeutic window of opportunity. Surgical techniques range from incision and drainage to wide excision, with varying recurrence rates mainly based on the extent of procedures. Reconstruction techniques would vary primarily based on the extent of the defect and the area involved. In all cases, a good preoperative planning and delimitation with imaging modalities, preferably intra- or perioperative facilitates complete removal of involved tissue, preserving the integrity and function of healthy skin and minimizing recurrences.

The Challenges of Assessing Hidradenitis Suppurativa: Outcome Measures

Accurate assessment of disease severity and treatment response are essential in the clinical management of hidradenitis suppurativa (HS) and vital in research efforts, particularly investigations of potential therapeutics. Key elements of the history and physical examination can inform treatment decisions to meet the needs of each individual patient. Over time, and through diligent and purposeful research, outcome measures capable of accurately and reliably assessing treatment response suitable for both research and clinical use have been developed and refined. This review explores HS clinical assessment, existing outcome measures, and emerging tools to enable accurate assessment, improve care, and optimize treatment strategies.

Enhancing Hidradenitis Suppurativa Assessment: The Role of Ultra-High Frequency Ultrasound in Detecting Microtunnels and Refining Disease Staging

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease affecting hair follicles, causing recurrent abscesses and nodules in intertriginous regions. The International HS Severity Score System (IHS4) is widely used to assess HS severity by counting inflammatory nodules, abscesses, and draining fistulas/tunnels. However, traditional clinical examinations may underestimate HS severity due to the presence of subclinical lesions. This study aims to enhance the accuracy of HS severity assessment by incorporating ultra-high frequency ultrasound (UHFUS) to detect subclinical lesions, such as microtunnels.

METHODS

A cohort of 122 patients with HS (75 females and 47 males) was evaluated. Clinical severity was assessed using the IHS4 scoring system. UHFUS assessments were performed using a 70 MHz probe for patients with mild and moderate IHS4 scores. Statistical tools were used to assess the significance of UHFUS in detecting additional lesions not identified during clinical examinations.

RESULTS

The study found that 23% of patients had mild HS, 58.2% had moderate HS, and 18.9% had severe HS according to IHS4. Among the 28 patients with mild IHS4, 14 had microtunnels detected by UHFUS, leading to a change in disease staging: 11.5% of patients were reclassified as mild, while 69.7% were reclassified as moderate. A statistically significant difference in the distribution of severity classifications before and after UHFUS examination was observed (χ2 = 5.11, P = .0238).

CONCLUSION

The study underscores the critical role of UHFUS as a non-invasive technique for the precise assessment of HS. The integration of UHFUS with a 70 MHz probe significantly enhances the detection of subclinical lesions, such as microtunnels, enabling timely intervention and potentially preventing disease progression. Despite the study's limitations, including its monocentric design and small sample size, the findings support the use of UHFUS in improving the accuracy of HS severity assessment.

[Translated article] Spanish Hidradenitis Suppurativa Registry (REHS) of the Spanish Academy of Dermatology and Venereology: Description and Data From its First Year of Operation

INTRODUCTION

Hidradenitis suppurativa (HS) is a skin disease that significantly impacts patients' quality of life. There are still uncertainties surrounding its epidemiology, natural history, and the safety and effectiveness of existing treatments. The Spanish Academy of Dermatology and Venereology has promoted the creation of a Spanish Registry of patients with HS (REHS). The aim of this article is to present the REHS and provide the initial results obtained.

METHODS

The REHS is a prospective, multicenter, observational study that collects the clinical and epidemiological characteristics of patients with HS, as well as the safety and effectiveness of the medical and surgical treatments received.

RESULTS

Between June 2023 and June 2024, 359 patients were recruited from 23 Spanish centers. The average age of the patients is 37 years, and 53% of them are women. Over 70% of the patients are smokers or former smokers. One third have a family history of HS. The most frequent sites of disease onset are the axillae and groin. Median baseline IHS4 at recruitment was 4 (p25-p75=1-9), HiSQOL was 20 (p25-p75=8-36), and BMI was 27.3 (p25-p75=24-33.2). At least 82% of patients have received antibiotic therapy for their disease, and almost 20% a biologic drug.

CONCLUSIONS

We present data from the first patients enrolled in the REHS, which will allow for the generation of evidence on the natural course of the disease, as well as the effectiveness and safety of treatments in HS.

Disease severity assessment in hidradenitis suppurativa: A single-centre cross-sectional study utilising clinical evaluation, high-resolution ultrasound and colour doppler

Background Hidradenitis suppurativa (HS) is a chronic inflammatory skin disorder characterised by recurrent painful nodules, abscesses, and sinus tract formation in intertriginous areas. Accurate staging of this disorder is crucial for appropriate management and prognosis. The role of imaging in the staging of HS is still evolving. Objectives To assess the correlation between clinical disease severity staging and high-resolution ultrasonography and colour doppler (HRUS-CD) staging in HS patients. Methods This was a cross-sectional, single-centre study in patients above 18 years of age with the clinical diagnosis of HS. All patients underwent clinical examination and high-resolution ultrasonography and colour doppler study with high-frequency linear probe (L+ 8-24 MHz). Correlations between clinical Hurley staging and the various ultrasonographic parameters i.e. SOS-HS (sonographic staging of severity of HS), degree of vascularisation, fibrotic scarring and oedema were explored and analysed. Spearman's correlation coefficient was applied to study the correlations and p<0.05 was considered significant. Results A total of 46 patients with HS who met the inclusion criteria were included. The majority of patients were clinically in Hurley stages 1 (32.6%; n=15) and 2 (56.5%; n=26) (41 in all). However, on the basis of ultrasonographic findings, significant numbers of patients had greater severity of staging on SOS-HS (58.5%; n=24/41), higher vascularity on colour doppler (26.8%; n=11), more severe grading of fibrous scarring (43.9%; n=18) and oedema (68.2%; n=28) in comparison to the clinical Hurley staging. Limitations Limitations of our study include a small sample size and cross-sectional design. Conclusion The results of the study indicate that the majority of the patients were under-staged and under-treated clinically, hence emphasising the role of high-resolution ultrasonography and colour doppler study in the accurate determination of HS severity. Future research should focus on standardised protocols and larger, prospective studies to establish the role of these imaging modalities in routine clinical practice.

Spanish Hidradenitis Suppurativa Registry (REHS) of the Spanish Academy of Dermatology and Venereology: description and data from its first year of operation

INTRODUCTION

Hidradenitis suppurativa (HS) is a skin disease that significantly impacts patients' quality of life. There are still uncertainties surrounding its epidemiology, natural history, and the safety and effectiveness of existing treatments. The Spanish Academy of Dermatology and Venereology has promoted the creation of a Spanish Registry of patients with HS (REHS). The aim of this article is to present the REHS and provide the initial results obtained.

METHODS

The REHS is a prospective, multicenter, observational study that collects the clinical and epidemiological characteristics of patients with HS, as well as the safety and effectiveness of the medical and surgical treatments received.

RESULTS

Between June 2023 and June 2024, 359 patients were recruited from 23 Spanish centers. The average age of the patients is 37 years, and 53% of them are women. Over 70% of the patients are smokers or former smokers. One third have a family history of HS. The most frequent sites of disease onset are the axillae and groin. Median baseline IHS4 at recruitment was 4 (p25-p75=1-9), HiSQOL was 20 (p25-p75=8-36), and BMI was 27.3 (p25-p75=24-33.2). At least 82% of patients have received antibiotic therapy for their disease, and almost 20% a biologic drug.

CONCLUSIONS

We present data from the first patients enrolled in the REHS, which will allow for the generation of evidence on the natural course of the disease, as well as the effectiveness and safety of treatments in HS.

Surgical Approach to Hidradenitis Suppurativa

Hidradenitis suppurativa is a chronic inflammatory skin condition characterized by painful nodules, abscesses, and sinus tracts that may lead to irreversible scarring complications. Therapeutic options include antibiotics, biologic therapies, and surgical procedures. Current management of hidradenitis suppurativa favors early surgical intervention along with medical therapy to promote healing and minimize scars and complications in a disease characterized by a therapeutic window of opportunity. Surgical techniques range from incision and drainage to wide excision, with varying recurrence rates mainly based on the extent of procedures. Reconstruction techniques would vary primarily based on the extent of the defect and the area involved. In all cases, a good preoperative planning and delimitation with imaging modalities, preferably intra- or perioperative facilitates complete removal of involved tissue, preserving the integrity and function of healthy skin and minimizing recurrences.

Update on the role of color Doppler ultrasound in hidradenitis suppurativa: a game-changer

Hidradenitis suppurativa has greatly benefited from the insights of color Doppler ultrasound. Thus, ultrasonography has helped prove the follicular link of this disease and has ruled out the primary involvement of the apocrine glands, which, in the old days, was supposedly the cause of the disease. Importantly, ultrasound can detect subclinical anatomical information in HS that cannot be deducted from the clinical examination. Moreover, high-frequency (≥15 MHz) and ultra-high-frequency (≥50 MHz) ultrasound present a much higher axial spatial resolution compared to magnetic resonance imaging. Ultrasound allows us to detect better subclinical cutaneous anatomical abnormalities and, therefore, arrive earlier and more accurately at diagnosis and staging. Ultrasonographic diagnostic criteria can discriminate HS from other clinical simulators, which is also critical in diagnosing mild and moderate stages and is relevant for the severe stages. This imaging technique supports the severity (mSOS-HS) and activity (US-HSA) scorings more accurately, which can help assess the actual stage of the disease. This is important to decide the type of treatment and to perform a more objective follow-up of the patients. Magnetic resonance imaging has been reported as helpful in diagnosing deep perianal tunnels; however, it presents a lower axial spatial resolution compared with high and ultra-high frequency ultrasound. Nowadays, there is solid evidence of the usefulness of ultrasound in HS, which implies that it is a game-changer and should be recommended as the first-choice imaging technique and a standard of care tool for HS patients.

Hidradenitis suppurativa

Hidradenitis suppurativa is a chronic inflammatory disease characterised by painful, deep-seated nodules, abscesses, and draining tunnels in the skin of axillary, inguinal, genitoanal, or inframammary areas. In recent years, the body of knowledge in hidradenitis suppurativa has advanced greatly. This disorder typically starts in the second or third decade of life. The average worldwide prevalence is 1% but varies geographically. Hidradenitis suppurativa has a profound negative effect on patients' quality of life and on the gross value added to society. Comorbidities (eg, metabolic syndrome, inflammatory arthritis, and inflammatory bowel disease) frequently accompany skin alterations, because of systemic inflammation. Pathogenesis of hidradenitis suppurativa is complex and includes innate immune mechanisms (eg, macrophages, neutrophils, IL-1β, tumour necrosis factor [TNF], and granulocyte colony-stimulating factor), T-cell mechanisms (eg, IL-17 and IFN-γ), and B-cell mechanisms (eg, associated with dermal tertiary lymphatic structures and autoantibodies). Chronic inflammation leads to irreversible skin damage with tunnel formation and morbid scarring. Current treatment includes drug therapy (for the initial, purely inflammatory phase), combined drug and surgical therapy (for the destructive phase), or surgery alone (for the burnout phase). The first systemic therapies approved for hidradenitis suppurativa targeting TNF (adalimumab) and IL-17 (secukinumab and bimekizumab) have expanded drug therapy options for moderate-to-severe disease, which were previously mainly restricted to oral antibiotics. Moreover, there is a robust pipeline of immunomodulatory drugs in various stages of development for hidradenitis suppurativa. Aims of management should include early intervention to prevent irreversible skin damage, adequate control of symptoms including pain, and mitigation of extra-cutaneous comorbidities, all requiring early diagnosis and an interdisciplinary, holistic and personalised approach.

Presurgical Mapping With Ultra-high Frequency Ultrasound of Hidradenitis Suppurativa Lesions Treated With Wide Local Excision and Secondary Intention Healing

BACKGROUND

Hidradenitis suppurativa (HS) is a challenging chronic inflammatory condition often requiring surgical intervention, such as wide local excision. Preoperative mapping with ultra-high frequency ultrasound (UHFUS) enables detailed assessment of lesion extension, particularly identifying tunnels and fistulas, facilitating surgical planning.

OBJECTIVE

This study aimed to analyze recurrence rates of HS lesions previously mapped with UHFUS and treated with wide excision and secondary intention healing.

MATERIALS AND METHODS

A retrospective single-center study enrolled 40 patients with HS undergoing wide excision surgery after UHFUS mapping. Patients were assessed weekly until complete healing and then every 3 months, evaluating clinical and sonographic signs of relapse and pain using the visual analogue scale.

RESULTS

Results showed a population predominantly composed of women (65%) with a mean age of 39 years and a medium HS-Hurley score of 2.5. Over a 22-month follow-up, only 10% experienced clinical relapse, achieving an 90% total remission rate. Pain scores decreased significantly from Week 0 to Week 4.

CONCLUSION

The study highlights the clinical challenge of HS management, particularly regarding surgical planning and lesion margin definition. The remission rate observed in this study suggests the effectiveness of UHFUS-guided surgical approaches. Future studies should extend observation periods to further validate these findings.

Essential Considerations for Radiologists in Diagnosing Hidradenitis Suppurativa

Hidradenitis suppurativa, also referred to as inverse acne, manifests as a persistent inflammatory skin disorder characterized by lesions such as deep nodules, abscesses, sinus tracts, and fibrotic scars. These manifestations predominantly occur in skin folds and intertriginous areas, notably in the axillary, inguinal, perianal, perineal, and inframammary regions. Due to similarities with other conditions in its initial stages, accurate diagnosis of hidradenitis suppurativa is often delayed, sometimes spanning several years. Diagnosis relies on identifying specific morphologic features (such as deep, inflamed, and painful nodules; sinus tracts; and scars), considering the affected sites (skin folds and areas with apocrine glands), and recognizing the chronic nature of the condition (persistent course with periods of exacerbation and remission). There are no definitive biologic or pathologic diagnostic tests, and biopsy of the affected area is not necessary. Treatment varies based on severity and may include topical and systemic antibiotics, hormonal therapy, immunomodulators, and surgery. Due to associated pain, increased site sensitivity, secretion drainage, odor, and scarring, this condition can have a negative psychosocial impact. Imaging studies, including high-frequency US and MRI with subsequent three-dimensional reconstruction, serve as valuable tools for precise staging, monitoring disease activity, and preoperative assessment. Currently, high-frequency US stands as the preferred method, incorporating sonographic classifications, while MRI and thee-dimensional imaging represent an emerging and promising approach. Imaging helps identify the extent of sinus tracts, assess involvement dimensions in advanced disease stages, and monitor proposed treatments. ©RSNA, 2024 Supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

Ultrasonography of Facial and Submandibular Hidradenitis Suppurativa and Concomitance With Acne Vulgaris

OBJECTIVES

To describe the ultrasound characteristics of facial and submandibular hidradenitis suppurativa (HS) and detect acne vulgaris (AV) concomitance in these cases.

METHODS

We performed a retrospective study of the ultrasound images of patients with facial HS who had been clinically evaluated by dermatologists. The reported ultrasound diagnostic criteria, severity (mSOS-HS), and activity (US-HAS) staging of HS were used to categorize the patients. The finding of fragments of hair tracts within the key lesions (dilated hair follicles, pseudocysts, fluid collections, and tunnels) was considered a pivotal sign to discriminate HS from AV. Demographic and morphological analysis of the images were considered.

RESULTS

Thirty-three patients met the criteria (78.8% male/21.2% female). Of these, the mSOS- HS scoring was stage I in 51.5%, stage II in 27.3%, and stage III in 21.2%. Dilation of the hair follicles and the presence of pseudocysts, fluid collections, and tunnels were detected in the HS cases; 63.1% of pseudocysts, 62.4% of tunnels, and 46.2% of fluid collections contained fragments of hair tracts. In all HS cases, there was a key lesion(s) with fragments of hair tracts. Four (12.1%) patients showed concomitant facial HS and acne ultrasound lesions. The acne lesions were pseudocysts without inner hair tract fragments in all cases, and the SOS-Acne scoring was stage II for all of them.

CONCLUSION

Facial HS can be detected on ultrasound and shows a morphology similar to that of HS in other corporal regions. In some cases, facial HS could be concomitant with AV. The subclinical ultrasonographic information can support a better management of these cases.

Doppler ultrasound protocol for patients with hidradenitis suppurativa

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic inflammatory disease that leads to the formation of nodules, abscesses and fistulas, with the formation of scars and fibrosis, causing significant impairment in patient quality of life. The diagnosis is clinical, using scores to classify the severity of the condition; currently the most recommended classification is the International Hidradenitis Suppurativa Severity Scoring System (IHS4). Doppler ultrasound has been used to complement the clinical evaluation of patients with HS. It is possible to observe subclinical lesions that change the staging, the severity of the case, and its treatment, either clinical or surgical. Correct treatment is essential to minimize the consequences of this disease for the patient.

OBJECTIVE

To establish an outpatient protocol for the use of Doppler ultrasound in the care of patients with HS.

METHODS

A narrative review of the literature was carried out on the use of Doppler ultrasound in patients with hidradenitis suppurativa; a referring protocol and technique orientations for imaging assessment in HS were created.

RESULTS

Recommendation to perform ultrasound evaluation of symptomatic areas eight weeks after using antibiotics and four, 12, and 24 weeks after starting immunobiologicals; apply SOS-HS ultrasound severity classification.

STUDY LIMITATIONS

The review did not cover all literature on ultrasound and HS; no systematic review was carried out, but rather a narrative one.

CONCLUSIONS

The correct assessment of patients staging must be carried out using dermatological ultrasound to avoid progression to scars and fibrosis, which compromise patients quality of life.

Role of Color Doppler Ultrasound in Cutaneous Inflammatory Conditions

Inflammatory cutaneous diseases can be challenging to diagnose and manage. Nowadays, the anatomical information provided by ultrasound is critical for detecting subclinical alterations and assessing the severity and activity of these conditions. Many of these entities can be clinically observed in dermatology and other specialties, such as rheumatology, plastic surgery, ophthalmology, and otolaryngology, among others. We review the ultrasonographic patterns of the most common inflammatory cutaneous conditions. In several cases, such as hidradenitis suppurativa, acne, and morphea, there are ultrasonographic staging systems of severity or activity that are pivotal in the management of these diseases. The early ultrasonographic diagnosis of these entities implies a proper management of the patients and, therefore, improve their quality of life. Thus, knowledge of the current use of ultrasound in this field seems essential.

Uncovering the burden of hidradenitis suppurativa misdiagnosis and underdiagnosis: a machine learning approach

Hidradenitis suppurativa (HS) is a chronic inflammatory follicular skin condition that is associated with significant psychosocial and economic burden and a diminished quality of life and work productivity. Accurate diagnosis of HS is challenging due to its unknown etiology, which can lead to underdiagnosis or misdiagnosis that results in increased patient and healthcare system burden. We applied machine learning (ML) to a medical and pharmacy claims database using data from 2000 through 2018 to develop a novel model to better understand HS underdiagnosis on a healthcare system level. The primary results demonstrated that high-performing models for predicting HS diagnosis can be constructed using claims data, with an area under the curve (AUC) of 81%-82% observed among the top-performing models. The results of the models developed in this study could be input into the development of an impact of inaction model that determines the cost implications of HS diagnosis and treatment delay to the healthcare system.

Gluteal Hidradenitis Suppurativa: Analysis of 83 Patients

BACKGROUND

In 2013, Canoui-Poitrine et al. identified three hidradenitis suppurativa (HS) phenotypes by a latent class (LC) analysis, based on anatomical sites of involvement.

OBJECTIVE

To improve the classification of the gluteal phenotype (LC3) patients given their diverse lesion types and differences in clinical profile.

MATERIAL AND METHODS

We designed a bicentric study gathering all LC3 patients (n=83) from two hospitals. We conducted a two-step cluster analysis among them and also compared their characteristics with the rest of the HS patients (n=661).

RESULTS

Compared with global HS series, LC3 patients were more frequently non-obese men, with smoking habit, an associated arthropathy, and a more frequent history of pilonidal sinus. The analysis of LC3 patients yielded two clusters: cluster 1 (38.3%) included elderly female patients, with later diagnosis of the disease and more sinus tracts; cluster 2 (61.7%) encompassed more men with earlier disease onset and more nodules and folliculitis lesions.

LIMITATIONS

The study's limitations include its retrospective nature, bicentric design, and small sample size.

CONCLUSION

The heterogeneous clinical presentation of HS makes it essential to have a good classification of the patients. Gluteal phenotype could actually be classified into two "subphenotypes" with a different clinical profiles and management.

Gluteal Hidradenitis Suppurativa: Analysis of 83 Patients

BACKGROUND

In 2013, Canoui-Poitrine et al. identified three hidradenitis suppurativa (HS) phenotypes by a latent class (LC) analysis, based on anatomical sites of involvement.

OBJECTIVE

To improve the classification of the gluteal phenotype (LC3) patients given their diverse lesion types and differences in clinical profile.

MATERIAL AND METHODS

We designed a bicentric study gathering all LC3 patients (n=83) from two hospitals. We conducted a two-step cluster analysis among them and also compared their characteristics with the rest of the HS patients (n=661).

RESULTS

Compared with global HS series, LC3 patients were more frequently non-obese men, with smoking habit, an associated arthropathy, and a more frequent history of pilonidal sinus. The analysis of LC3 patients yielded two clusters: cluster 1 (38.3%) included elderly female patients, with later diagnosis of the disease and more sinus tracts; cluster 2 (61.7%) encompassed more men with earlier disease onset and more nodules and folliculitis lesions.

LIMITATIONS

The study's limitations include its retrospective nature, bicentric design, and small sample size.

CONCLUSION

The heterogeneous clinical presentation of HS makes it essential to have a good classification of the patients. Gluteal phenotype could actually be classified into two "subphenotypes" with a different clinical profiles and management.

Update on Ultrasound Diagnostic Criteria and New Ultrasound Severity and Activity Scorings of Hidradenitis Suppurativa: Modified SOS-HS and US-HSA

Hidradenitis suppurativa (HS) is a devasting autoimmune cutaneous disease that affects the hair follicles and can clinically present palpable nodules, abscesses, and tunnels (fistulas), usually in the intertriginous regions. It has been widely reported that color Doppler ultrasound can detect subclinical abnormalities and stage the severity of the disease more accurately. Nevertheless, the ultrasound diagnostic criteria were reported with 15 MHz 10 years ago, and now it is possible to detect early anatomical abnormalities in HS using 70 MHz. Thus, an update of the ultrasonographic diagnostic criteria is needed. The most widely used sonographic staging of severity of HS (SOS-HS) includes the number of affected regions, besides counting the number of key lesions like pseudocysts, fluid collections, and tunnels; however, the total number of affected regions may fit better in an activity scoring. Furthermore, a high number of tunnels or communicated tunnels can complicate the management and may indicate an even more urgent treatment, which should be considered in the severity classification. To date, no hidradenitis scoring of activity has been reported in the literature, making it difficult to track the degree of inflammation under treatment objectively. Therefore, two new scorings are proposed. The first is an updated sonographic scoring of severity called modified SOS-HS (mSOS-HS), and the second is an activity ultrasound scoring of HS called US-HSA. Both staging systems can provide better anatomical information for discriminating the categories and, therefore, selecting more appropriate treatments and supporting research and clinical trials by giving more objective anatomical tools in real-world settings.

The role of imaging technologies in the diagnosis of hidradenitis suppurativa

Hidradenitis suppurativa is a chronic, inflammatory, recurrent, and debilitating disease of the hair follicle. It presents with painful, deep-seated, inflamed lesions, such as nodules, abscesses, sinus tracts, and fistulas, generally located in the main folds. Clinical severity assessment alone can be reductive; noninvasive skin imaging technologies, such as ultrasound, magnetic resonance imaging, medical infrared thermography, computed tomography, and positron emission tomography, provide subclinical anatomical and functional details. These instrumental techniques confirm the clinical suspect, thus allowing an earlier diagnosis and improving patients' clinical evaluation, staging, and management. Finally, they might be helpful for preoperative mapping. In this contribution, we provide an overview of the current knowledge about noninvasive skin imaging techniques with a particular focus on ultrasonography, which is widely used thanks to its precision, versatility, and availability.

Color Doppler Ultrasound Assessment of Subclinical Activity With Scoring of Morphea

BACKGROUND

Detection of activity in morphea is paramount for adequately managing the disease. Subclinical ultrasound involvement on inactive lesions or healthy skin areas adjacent to morphea has not been described to date.

OBJECTIVES

The study aimed to detect morphea's subclinical activity by Color Doppler ultrasound not identified with the clinical scorings.

MATERIALS & METHODS

This cross-sectional retrospective study was done from January 2014 to July 2019 in patients with a clinicopathological diagnosis of morphea. The modified Localized Scleroderma Skin Severity Index (mLoSSI) and The Ultrasound Morphea Activity Score (US-MAS) were used to correlate clinical and subclinical activity.

RESULTS

A total of 36 patients met the inclusion criteria. 54% of cases presented subclinical activity in areas adjacent to the clinically active lesion, 23% in nonadjacent regions, and 23% demonstrated activity at a clinically inactive lesion site.100% of patients with morphea "en coup de sabre" involving the frontal region of the face concomitantly presented both subclinical activities of morphea on the frontal facial region and the scalp following the same axis.A positive relationship was observed between the degree of clinical activity measured by mLoSSI and US-MAS scoring.The main limitations of our study were the low number of patients and the inability to detect alterations < 0.1 mm.

CONCLUSIONS

Subclinical activity is frequent in morphea, can extend beyond the lesional areas, including apparently noninvolved adjacent and distant corporal regions, and can be detected by color Doppler ultrasound.

Assessment tools and phenotype classification for hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a heterogeneous chronic relapsing skin disease. Several assessment tools are used to assess disease severity and to classify disease phenotype; however, no consensus exists. This review evaluates the various assessment tools and phenotypes, assessing their validity and reliability. Numerous assessment tools and phenotype classifications have been proposed for identifying various subtypes within the hidradenitis suppurativa disease spectrum. Each has a different purpose, such as use in daily practice or in clinical trial settings. Several assessment tools and phenotype classifications have been validated but not always with satisfactory results and often with studies showing divergent intra-rater reliability results. A consensus is needed for a validated, easy-to-use, and timesaving assessment tool for routine daily practice. For clinical trials, a validated and extensive assessment tool that also measures response to treatment is also needed.

Key Points to Select a Device for Dermatologic Ultrasound

What points to consider when selecting a device for practicing dermatologic ultrasound is an excellent question. After we met the requisites published in the guidelines for practicing dermatologic ultrasound, it is necessary to consider the main objective of the use because it is not the same to be focused mostly on the avoidance of the puncture of important facial vessels such as the case of injectors of cosmetic fillers in comparison to the use of operators that need to deal with the diagnosis and monitoring of a wide range of dermatologic pathologies. Currently, a broad variety of ultrasound devices meets the minimum requirements for practicing these examinations in the market. Thus, small, portable, and high-end devices may present advantages and limitations that must be balanced according to the primary purposes and the budget. Moreover, the shape and footprint of the probes can make difficult or facilitate a dermatologic procedure. Other points to consider are the type of storage and the need for technical service. In summary, there are key points that we need to consider when we select a dermatologic ultrasound device in dermatology or aesthetics.

[Guidelines for the Management of Patients with Hidradenitis Suppurativa]

Hidradenitis suppurativa is a chronic and recurrent inflammatory dermatosis characterized by the presence of inflammatory nodules and abscesses in the apocrine gland-rich areas that may progress to suppurative fistulas and scars. Despite being considered one of the dermatological conditions with the greatest impact on patient quality of life, it is often underdiagnosed. Hidradenitis suppurativa, especially in its severe forms, is associated with numerous comorbidities, so a holistic and multidisciplinary perspective is crucial for the management of these patients. The therapeutic approach is complex and challenging. The medical treatment options are diverse and must be adapted to clinical presentation and disease severity. Surgical therapy should be considered as an adjuvant to medical treatment, particularly in refractory cases and in the presence of scars or anatomical and/or functional mutilation. These recommendations reflect the main aspects of the management of the patient with hidradenitis suppurativa and are addressed to all healthcare professionals who take part in their follow-up.

Value of high‐frequency ultrasound in the treatment of moderate and severe acne vulgaris

BACKGROUND

Acne treatment may fail or cause undesirable side effects due to inaccurate evaluation. High-frequency ultrasound (HFUS) can monitor systemic treatment in patients with moderate-to-severe acne vulgaris.

MATERIALS AND METHODS

In this prospective study, consecutive patients with moderate-to-severe acne vulgaris were recruited. Patients were graded by a comprehensive clinical assessment before and after therapy. Simultaneous HFUS grading was independently evaluated according to the sonographic scoring system for acne (SSSA). Clinical and HFUS grades were compared through kappa analysis.

RESULTS

A total of 70 patients were enrolled. At baseline, 36 (51.4%) and 34 (48.6%) patients were graded as moderate and severe, respectively, through clinical assessment. However, 27 patients (38.6%) scored SSSA-Grade II and 43 (61.4%) scored SSSA-Grade III in the HFUS grading. Sixty-one patients (87.1%) were in the consistent category as per clinical assessment and HFUS grades, with Kappa₁  = 0.745, whereas higher HFUS grades were observed in nine patients. By the end of the observation, 65 of all patients (92.9%) showed significant improvement and 5 (7.1%) showed no apparent improvement after the treatment. According to the clinical assessment, 14, 52, and 4 patients were graded as mild, moderate, and severe, respectively. On the other hand, 11, 51, and 8 patients had SSSA-Grade I, II, and III, respectively. Of all patients, 63 (90.0%) had consistent evaluation results, with Kappa₂  = 0.762, whereas the remaining seven patients had an HFUS grade higher than the clinical.

CONCLUSION

HFUS is a useful tool for dermatologists to monitor the treatment of moderate and severe acne vulgaris.

Practical Guidelines for Managing Patients With Hidradenitis Suppurativa: An Update

Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease that is characterized by the formation of comedones, papules, nodules, abscesses and sinus tracts in the axillary, inframammary, groin, and gluteal areas. Up to 3.8% of the Canadian population has HS, though due to a lack of awareness of HS, many patients are initially misdiagnosed and do not receive adequate treatment early on in the disease course. Once a diagnosis of HS is made, developing an effective management plan can be a dilemma for many providers. There is significant variability in response to any given therapy within the HS patient population and many HS patients have other medical comorbidities which must be taken into consideration. The aim of this review is to provide a practical approach for all healthcare providers to diagnose and manage HS and its associated comorbidities. A sample electronic medical record template for HS management was developed by the Canadian Hidradenitis Suppurativa Foundation Executive Board and is intended for use in clinical settings. This will help to increase collaboration between primary healthcare providers, dermatologists, and other medical specialists and ultimately improve the quality of care that HS patients receive.

Hidradenitis Suppurativa: morphologic and vascular study of nodular inflammatory lesions by means of optical coherence tomography

BACKGROUND

Hidradenitis Suppurativa (HS) is an inflammatory disease characterized by a recurrent-remission trend and clinical lesions that range from asymptomatic to inflamed, deep-seated nodules with scarring and suppuration.

OBJECTIVE

To identify morphologic and vascular features of HS nodules by means of dynamic optical coherence tomography (D-OCT) and to define if they are correlated to patient endotype and risk of disease progression.

METHODS

A set of standardized clinical pictures and D-OCT images were acquired from 57 inflammatory nodules of 40 patients affected by HS. A set of 20 clinical and D-OCT images were acquired from 20 healthy volunteers as a control group. The comparison of D-OCT features among HS and control group was analyzed. The correlation between HS patient endotype and D-OCT features of the lesions was calculated.

RESULTS

D-OCT enabled to identify vascular and morphological aspects characterizing HS nodular inflammatory lesions. In addition, several D-OCT features were significantly different among distinct disease endotypes.

CONCLUSION

The characterization of HS nodular inflammatory lesions through D-OCT, corresponding to blood vessel dilation and inflammatory associated hyper-vascularization, may have important clinical consequences in the assessment of HS risk of progression, therapeutic decisions and treatment efficacy monitoring.

The EFSUMB Guidelines and Recommendations for Musculoskeletal Ultrasound - Part I: Extraarticular Pathologies

The first part of the guidelines and recommendations for musculoskeletal ultrasound, produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB), provides information about the use of musculoskeletal ultrasound for assessing extraarticular structures (muscles, tendons, entheses, ligaments, bones, bursae, fasciae, nerves, skin, subcutaneous tissues, and nails) and their pathologies. Clinical applications, practical points, limitations, and artifacts are described and discussed for every structure. After an extensive literature review, the recommendations have been developed according to the Oxford Centre for Evidence-based Medicine and GRADE criteria and the consensus level was established through a Delphi process. The document is intended to guide clinical users in their daily practice.

Practical applications of ultrasound in dermatology

Ultrasound has evolved in dermatology from an experimental phase to a daily practice imaging technique. Its several advantages include its safety, good balance between penetration and resolution, high definition, and the detection of blood flow in real time. Its applications are growing and include the support of the diagnosis and extent in all axes, including depth, vascularity patterns, staging, and follow up of multiple cutaneous diseases-benign cutaneous tumors, vascular anomalies, nail lesions, skin cancer, inflammatory cutaneous diseases, and aesthetics complications.

Overview of Ultrasound Imaging Applications in Dermatology

Complete visualization of lesions is critical for the accurate diagnosis and management of dermatological diseases. Currently, the most readily available technologies used by dermatologists include dermoscopy and photography. Nevertheless, ultrasound has emerged as a useful non-invasive modality in dermatology, which can be added to the clinical examination supporting an early and more accurate diagnosis. Moreover, there are significant technological advances in recent years, such as the development of handheld devices and ultra-high frequency probes that have expanded the integration of ultrasound into daily dermatology practice. In this article, we reviewed the most common applications of ultrasound in the field of dermatology.

Assessment of Inter-rater Reliability of Clinical Hidradenitis Suppurativa Outcome Measures Using Ultrasonography

BACKGROUND

Hidradenitis suppurativa (HS) staging and severity is typically based upon physical examination findings which can result in misclassification of severity based on subclinical disease activity and significant variation between healthcare providers. Ultrasound (US) is an objective tool to help evaluate subclinical disease and more accurately classify severity of disease. The objective of this study was to evaluate inter-rater reliability in HS disease severity assessment using clinical and US techniques.

METHODS

Twenty subjects underwent clinical evaluation of HS using clinical outcome measures including Hurley, Sartorius, HS Physician Global Assessment (HS-PGA), and Hidradenitis Suppurativa Clinical Response (HiSCR) independently by two physicians. US was subsequently performed, and clinical assessments were repeated. Intra-class correlation coefficients (ICC) were obtained to evaluate inter-rater agreement of each outcome measure before and after US.

RESULTS

Pre- to post-US improvement in ICC was seen with the Sartorius, HiSCR nodule and abscess count, and HiSCR draining fistula count. The scores went from having "good" rater agreement for Sartorius and HiSCR nodule and abscess count and "poor" rater agreement for HiSCR draining fistula count to "excellent" rater agreement amongst these scores.

CONCLUSIONS

US improved inter-rater agreement and should be used in conjunction with physical examination findings to evaluate disease severity to ensure uniform staging.

Quality of Life in Hidradenitis Suppurativa: An Update

Knowledge on hidradenitis suppurativa/acne inversa (HS) is rapidly increasing. HS has a profound impact on patients and their family life. Several factors, such as comorbidities, unemployment and HS severity, make this impact even more severe. The most widely used instrument to measure this impact is the dermatology-specific DLQI. We also identified six HS-specific health-related quality of life (HRQoL) instruments. Of them, HIDRAdisk, HSIA, HiSQOL and HSQoL-24 are better validated but there is still lack of experience of its use. Several treatment methods showed positive effect on patients’ HRQoL. Surgery remains a method with a substantial positive effect on HRQoL. Several studies confirming a positive effect of adalimumab on the HRQoL of patients with HS were published during the last three years. Data on the influence of several other biologics on HRQoL of HS patients are controversial or based on studies with a small number of patients.

High-frequency ultrasound as a scientific tool for skin imaging analysis

Ultrasonic imaging is one of the most important diagnostic tools in clinical medicine due to its cost, availability and good correlation with pathological results. High-frequency ultrasound (HFUS) is a technique used in skin science that has been little explored, especially in comparison with other sites and imaging techniques. HFUS shows real-time images of the skin layers, appendages and skin lesions in vivo and can significantly contribute to advances in skin science. This review summarizes the potential applications of HFUS in dermatology and cosmetology, with a focus on quantitative tools that can be used to assess various skin conditions. Our findings showed that HFUS imaging is a reproducible and powerful tool for the diagnosis, clinical management and therapy monitoring of skin conditions. It is also a helpful tool for assessing the performance of dermatological products. This technique may eventually become essential for evaluating the performance of dermatological and cosmetic products.

Vulvar hidradenitis suppurativa: Clinical cross-sectional study of 25 patients

Hidradenitis suppurativa (HS) involving the vulva is seldom reported in the gynecological or dermatological literature. The aim of this study was to describe the clinical characteristics of HS with vulvar affectation (VHS) and to compare it with patients without vulvar involvement. A cross-sectional study was conducted in a tertiary academic referral centre in Spain from May 1, 2015 to October 1, 2019. This study included 230 women with HS diagnosed in our hospital, 25 of them had vulvar involvement. In order to clinically characterize patients, demographic factors, comorbidities, clinical features, prescribed treatments and complications were recorded. The VHS group presented later median age of onset and lower body mass index (BMI) (P = 0.048), they mainly belonged to latent class 2 (LC2) and LC3 phenotypes involving groins, perineal and pubic area. A higher incidence of psychiatric disease was found in VHS (32% vs 10.7%). Significant positive association with fistula (P < 0.001), LC2 phenotype (P = 0.014), acne (P = 0.021) and thyroid disease (P = 0.006), and negative association with axillar lesions (P = 0.001) were noted. Ultrasonographical study of vulvar lesions demonstrated that most of them were fistulas with high Doppler signal suggestive of high inflammatory load. In conclusion, VHS is mostly seen in women with later onset and lower BMI and higher incidence of psychiatric disease compared to those without vulvar involvement. It is clinically characterized by the presence of fistulas and barely absent axillary involvement. Early diagnosis and treatment could be essential to prevent complications and quality of life impairment.

European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) Position Statement on Dermatologic Ultrasound

Dermatologic ultrasound is a recent application of ultrasound for the evaluation of healthy skin and appendages and their diseases. Although the scientific literature regarding this application is still not sufficient for evidence-based guidelines, general recommendations issued by scientific societies are necessary. The EFSUMB (European Federation of Societies for Ultrasound in Medicine and Biology) steering committee for dermatologic ultrasound has developed a series of consensus position statements regarding the main fields of dermatologic ultrasound (technical requirement, normal skin and appendages, inflammatory skin diseases, tumoral skin diseases, aesthetic dermatology and practice-training requirements). This document is the foundation for future evidence-based recommendations and guidelines for dermatologic ultrasound practice.

Dermatologic Ultrasound in Primary Care: A New Modality of Teledermatology: A Prospective Multicenter Validation Study

OBJECTIVES

This study aimed to validate dermatologic ultrasound as a complementary teledermatologic imaging modality in primary and tertiary care centers.

METHODS

Six primary care centers and 1 tertiary care dermatology department collaborated in the program. Images were sent through the institutional teledermatologic platform to the tertiary care dermatology department. At the reference hospital, ultrasound images and clinical data were received and registered by a physician trained in dermatologic ultrasound. An in-person consultation was scheduled to confirm the teleultrasound diagnosis. The time of response by the tertiary center, quality and size of the teledermatologic image, and concordance with the in-person diagnosis were assessed for each dermatologic lesion.

RESULTS

A total of 147 teleultrasound consultations with 143 patients (93 women and 50 men; mean age ± SD, 47 ± 23 years) were evaluated between June 2018 and January 2019. Nine teleultrasound consultations (6.1%) were not valid. Discordance between teleultrasound and the in-person diagnosis was evident in 6 of 138 cases (4.3%). Most cases corresponded to benign skin tumors (66.7%), followed by inflammatory skin lesions (15.9%), nonmelanoma skin lesions (13%), and other skin lesions (4.3%). All malignant tumors were detected (sensitivity, 100%), although 2 cases of benign lesions were telediagnosed as malignant (specificity, 97.8%). The positive and negative predictive values of a teleultrasound diagnosis of cutaneous malignancy were 90% and 100%, respectively.

CONCLUSIONS

Asynchronous primary care teleultrasound combined with dermatologic ultrasound training at tertiary centers is an effective teledermatologic modality.

Usefulness of ultrasound in dermatofibrosarcoma protuberans and correlation with histopathological findings: A series of 30 cases

BACKGROUND

Small series of ultrasound findings in dermatofibrosarcoma protuberans (DFSP) have been published, but the usefulness of this technique as a preoperative planning tool for tumor resection has not been studied.

MATERIALS AND METHODS

We retrospectively reviewed patients with DFSP at our hospital that underwent ultrasound examination. Depth of invasion was evaluated by ultrasound and histopathology. Accuracy of ultrasound for assessing depth of tumor invasion was estimated.

RESULTS

Thirty histopathologically confirmed DFSPs were studied. Classic finger-like projections were observed in 73.3% of cases. A posterior hyperechoic area extending deep into the subcutaneous tissue correlated with the honeycomb DFSP pattern and was observed in 53.3% of patients. Concordance between ultrasound and histopathologic depth measurements was excellent. Lateral tumor extension and Doppler activity were not evaluated in our series.

CONCLUSION

Ultrasound showed excellent prediction of depth of invasion. Further studies are required to define the usefulness of ultrasound for determining lateral tumor extension.

Vascularization and fibrosis are important ultrasonographic tools for assessing response to adalimumab in hidradenitis suppurativa: Prospective study of 32 patients

Hidradenitis suppurativa (HS) is a debilitating skin disease presenting with nodules, abscesses, and fistulae preferentially in the main folds. Adalimumab is the only licensed biologic for moderate-to-severe HS. Ultrasound demonstrated good sensitivity to provide anatomic and functional information in HS; in particular assessing vascularization, related to inflammation, and fibrosis in HS lesions before and after adalimumab treatment with ultrasound and Color Doppler may integrate clinical evaluation with imaging. Patients with moderate-to-severe HS were enrolled in this observational prospective study. Clinical evaluation (according to Hurley classification and International Hidradenitis Suppurativa Severity Score System score) and ultrasound (according to US HS-PGA)/Color Doppler were performed at baseline and after 12 weeks of adalimumab. Ultrasound was used for assessing fibrosis and Color Doppler for vascularization. For each patient, the three most severe lesions among abscesses and fistulae were chosen for total 96 lesions. Thirty-two patients were included, 18 men (56%) and 14 women (44%) with mean age 41.2. Mean IHS4 was 22.4 at baseline and dropped to 14.7 at week 12. Based on US HS-PGA, 14 out of 32 patients fell down by one or more classes of severity. Interestingly, adalimumab led to overall decrease in vascularization, particularly in lesions with intense vascular flow, which were 78 (81.3%) at baseline and became only 25 (26.04%). Finally, marked increase in fibrosis was seen after adalimumab, notably in lesions without fibrosis, which were 81 (84.4%) at baseline and became 15 (15.6%). This study confirms the efficacy of adalimumab in HS and provides value for vascularization and fibrosis as important ultrasonographic tools integrating clinical scores.

Hidradenitis Suppurativa: Proposal of Classification in Two Endotypes with Two-Step Cluster Analysis

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic, inflammatory, recurrent disorder of the pilosebaceous unit. Currently, several attempts have been made to classify this disease according to its pathogenesis and clinical manifestations. We attempted at classifying 103 patients using two-step cluster analysis.

METHODS

The final model included body mass index, C-reactive protein (CRP), and serum concentrations of IL-1, IL-6, IL-17, and IL-10 as continuous variables, and sex, later/early onset, anterior/posterior lesion sites, presence/absence of sinus tracts, nodules and abscesses, positive/negative history of pilonidal sinus, and presence/absence of mutations in gamma-secretase subunits (APH1A, APH1B, MEFV, NCSTN, PSEN1, PSEN2, PSENEN, PSTPIP1) as qualitative variables.

RESULTS

The resultant model defined two groupings or clusters: cluster 1 (64.9% of patients) characterized by nonobese males, with nodular lesions in posterior sites, early-onset HS, higher IL-10, presence of gamma-secretase mutations, and history of pilonidal sinus; and cluster 2 (35.1% of patients) characterized by obese females or males, with lesions in anterior sites, more presence of sinus tracts and abscesses and less nodules, later-onset HS, and higher concentrations of IL-1, CRP, IL-17, and IL-6. Severity measures (Hurley, HS-PGA, and IHS4) and tobacco use were discarded because the analysis found them to be less relevant for clustering.

CONCLUSION

Our resultant model confirms the clinical impression that HS is a disease spectrum with two pathogenic poles defining two clusters or endotypes. The probability of having severe disease was equally distributed in the two clusters. The variable with the highest predictive value for clustering was involvement of typical anterior sites (axillae, submammary) or atypical posterior sites (back, gluteal). Serum concentrations of interleukins, tobacco use, and sex had a lower predictive power for clustering.

Hidradenitis Suppurativa Area and Severity Index Revised (HASI-R): psychometric property assessment

BACKGROUND

Validated, reliable, globally accepted outcome measurement instruments for hidradenitis suppurativa (HS) are needed. Current tools to measure the physical signs domain for HS rely on lesion counts, which are time-consuming and unreliable.

OBJECTIVES

To assess the reliability and validity of the Hidradenitis suppurativa Area and Severity Index Revised (HASI-R) tool, a novel method for assessing HS severity, incorporating signs of inflammation and body surface area involved.

METHODS

The measurement properties of the HASI-R tool were evaluated. The tool was created by combining the previously published HASI and Severity and Area Score for Hidradenitis instruments. Twenty raters evaluated 15 patients with HS in a hospital-based ambulatory dermatology clinic. The objectives of the study were to assess inter- and intra-rater reliability of the HASI-R and its components, as well as its construct and known-groups validity. Existing lesion count-based clinician-reported measures of HS and their components were also assessed. Raters were also asked their preferences regarding the various HS severity assessment tools.

RESULTS

The HASI-R had moderate inter-rater reliability [intra-class correlation coefficients (ICC) 0·60]. This was better than all other HS physical sign outcome measures evaluated, which had poor inter-rater reliability (ICC < 0·5). HASI-R had the highest intra-rater reliability (ICC 0·91). The HASI-R had good construct validity and demonstrated known-groups validity. The HASI-R was also the most preferred tool by all raters.

CONCLUSIONS

Results from the clinometric assessment of the HASI-R are encouraging, and support continued evaluation of this clinician-reported outcome measure.

Clinical selection criteria in new clinical trials of hidradenitis suppurativa: External validity and implications on the daily clinical practice

INTRODUCTION

There are an increasing number of biologic drugs in the pipeline for treating hidradenitis suppurativa (HS). Clinical trials for these drugs usually share the same clinical selection criteria.

OBJECTIVES

(a) To describe the clinical profile of HS patients receiving first-line biologic treatment in an HS clinic setting, (b) to assess how this population would meet clinical criteria to participate in a clinical trial, and (c) to assess treatment effectiveness at week 16 in eligible vs non-eligible patients.

METHODS

Prospective observational study. Patients were grouped according to their eligibility for clinical trials. The effectiveness of adalimumab was assessed by HiSCR, IHS4-category-change and a-50%-reduction on IHS4 at week 16.

RESULTS

Thirty-eight patients were included in the study: eight (21.05%) were eligible for clinical trials and 30 (78.95%) were not. The main reason for non-eligibility was not having an AN count ≥5. Both groups presented similar number of draining tunnels. Effectiveness at week 16 was lower in non-eligible than eligible patients when evaluated by HiSCR-response but similar if evaluated by the IHS4-category-change or the 50%-reduction in IHS4.

CONCLUSION

In our population, the external validity of current eligibility criteria for clinical trials is low. Most patients receiving adalimumab in real-life setting would not be eligible for clinical trials.

Doppler ultrasound-based noninvasive biomarkers in hidradenitis suppurativa: evaluation of analytical and clinical validity

BACKGROUND

There is a need for valid and reliable biomarkers in hidradenitis suppurativa (HS) for diagnosis and disease activity monitoring. Imaging-based biomarkers have the potential to fulfil this unmet need but no evaluation of analytical or clinical validity has yet been undertaken.

OBJECTIVES

To evaluate the analytical and clinical validity of sonographic epidermal thickness, Doppler ultrasound and dermal tunnel diameter in patients with HS.

METHODS

Twenty-two participants with HS were recruited and underwent a total of 65 matched ultrasound and skin biopsies of lesional, perilesional and unaffected tissue. Ultrasound measurements were performed in triplicate with mean values used. Skin biopsies underwent immunohistochemistry as per previously published methods. Analytical validity was assessed in individual ultrasound-biopsy pairs (n = 65) by comparisons of sonographic variables with histological correlates. Clinical validity was assessed in individual patients (n = 22) by comparing measures of overall disease activity with sonographic outcomes.

RESULTS

Epidermal thickness, dermal tunnel diameter and power Doppler intensity were assessed. Sonographic epidermal thickness and dermal tunnel diameter have high analytical validity with corresponding histological measurements. Power Doppler intensity demonstrated high correlation with dermal CD3⁺ and CD11c⁺ cell counts but not neutrophil elastase-positive cells. Power Doppler ultrasound has significant correlation with pain scores, abscess and nodule count, International HS Severity Scoring System score and number of draining tunnels.

CONCLUSIONS

Sonographic epidermal thickness and dermal tunnel diameter have acceptable levels of analytical validity in the assessment of HS lesions. Power Doppler intensity demonstrates acceptable clinical and analytical validity, suggesting it is a valid imaging-based biomarker in HS.