The bacteriology of hidradenitis suppurativa

Unraveling the Skin Microbiome in Hidradenitis Suppurativa: Implications for Treatment and Disease Progression

Background: Hidradenitis suppurativa (HS) is a chronic, disabling, and disfiguring inflammatory disease with a complex, incompletely elucidated pathogenesis. The role of skin dysbiosis in the development and progression of HS has not yet been clarified. Methods: We performed an observational, prospective culture-based study that included 40 HS patients and analyzed the bacterial load and diversity in HS skin lesions, their correlation with disease severity, and several host and environmental factors. Additionally, we investigated the prevalence of antibiotic resistance and determined the resistance profile of bacterial strains isolated from chronic HS lesions. Results: An impressive number and diversity of bacterial strains were isolated from both superficial and deep HS lesions. 201 aerobic and anaerobic bacterial strains were isolated, polymicrobial growth being detected in the majority of samples. The most frequently isolated bacteria were Staphylococcus epidermidis, Staphylococcus aureus, Staphylococcus lugdunensis, Peptoniphilus spp., and Enterococcus faecalis in superficial lesions and Staphylococcus epidermidis, Staphylococcus aureus, and Corynebacterium tuberculostearicum in deep lesions. A significantly higher bacterial density and diversity was found in male patients, regardless of the affected area and in patients with severe HS. The proportion of bacterial strains resistant to antibiotics was lower in our study (8.95%) compared to the previously reported data. Conclusions: Our findings indicate dysbiosis as a key player in the initiation and maintenance of the inflammatory process in HS. Further large-scale, prospective studies are required to comprehensively characterize the microbiological landscape of HS and shed light on its contribution in the pathogenesis of the disease.

Microbiome Perturbations in Hidradenitis Suppurativa

Skin and gut microbiome perturbations may play a role in hidradenitis suppurativa (HS) pathogenesis. Emerging microbiome research has established the complex roles of the skin and gut microbiomes in health maintenance and disease. Perturbations in the HS skin microbiome have been shown to correlate with HS disease severity. HS gut microbiome characterization studies point to a trend in decreased microbial diversity associated with HS. Future research efforts examining microbiome perturbations and their functional implications longitudinally and in the setting of interventions are needed to build on this foundational knowledge.

Skin and Gut Microbiome in Hidradenitis Suppurativa: A Systematic Review

Hidradenitis suppurativa (HS) is a chronic skin disease that significantly impairs the quality of life of affected individuals. The disease is characterized by persistent purulent lesions in specific anatomical areas, and its pathophysiology involves multiple factors, including inflammation, genetics, the microbiome, and environmental components. Recent research suggests a potential role for pathogenic bacteria in HS, highlighting the importance of the communication between the human host and the microbiome in maintaining homeostasis and immune system reactivity. However, the exact mechanisms underlying the gut-skin microbial interactions in HS remain unclear. This systematic review aims to examine the existing literature on the differences in skin and gut microbiome composition between HS patients and healthy controls. The review identifies methodological inconsistencies and calls for further research to elucidate the microbiome's role in HS pathogenesis and to explore new therapeutic interventions. The review highlights the need for advancements in microbiome research methodologies, such as metataxonomics and metagenomics, to improve our understanding of the microbiota's impact on health and disease.

Cervicofacial hidradenitis suppurativa: A case report and literature review

Hidradenitis suppurativa (HS) is a chronic inflammatory condition of the apocrine glands primarily affecting the axillae, perineum, and inframammary regions. It is characterized by painful, inflamed cutaneous lesions causing nodules, sinus tracts, and abscesses. Cervicofacial HS is an atypical presentation of HS in the head and neck region and is scarcely reported in the literature. We present a 34-year-old male who developed a large facial swelling overlying the left inferior mandibular border. Management included surgical incision and drainage, antibiotic therapy, followed by infliximab (Remicade). The purpose of this case report was to highlight the presentation, pathophysiology, interdisciplinary approach to treatment and follow-up of patients with cervicofacial HS, and finally, review the cervicofacial HS literature.

Consistency of Bacterial Triggers in the Pathogenesis of Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is an inflammatory skin disease whose pathogenesis remains poorly defined. Over the past decades, the bacterial role in HS patients has been a focus of research. According to the literature, the HS skin (and probably gut) bacterial composition is different to that of healthy controls. To date, a key question is whether compositional changes in the microbial populations are responsible for the development of HS (primum movens), or only secondarily reflect the ongoing inflammatory process. The great diversity of methodologies that have been used to study microbial role in HS have led to an accumulation of conflicting results. Thus, in view of these considerations, the aim of this article is to provide the reader with an overview about different hypotheses proposed to explain the bacterial role in HS pathogenesis.

Medical infrared thermography as hidradenitis suppurativa diagnostic tool: literature review

Hidradenitis suppurativa (HS) is a rare, chronic, inflammatory skin disease that has a strong impact on the quality of life. Medical infrared thermography (MIT) is a non-invasive imaging method that could be used for evaluation of skin inflammation, which is an important biomarker in HS. We performed a comprehensive review of the literature to verify the possibilities of using MIT for HS. Key words “hidradenitis suppurativa”, “acne inversa” and “thermography” were used for PubMed, Embase and Scopus literature analysis and in total four articles fulfilled the inclusion criteria. The inflamed areas have shown the increase in temperature (34.3°C) and after the removal of lesions the temperature has become similar to the healthy skin sites. The margins of the inflammatory lesions identified by MIT were used in the surgical treatment. Also, MIT was used in combination with other imaging tests for inflammation evaluation. Thermography is an advantageous tool to detect inflammation and to secure the success of surgical treatment.

Yin and Yang: A disrupted skin microbiome and an aberrant host immune response in hidradenitis suppurativa

The skin microbiome plays an important role in maintaining skin homeostasis by controlling inflammation, providing immune education and maintaining host defense. However, in many inflammatory skin disorders the skin microbiome is disrupted. This dysbiotic community may contribute to disease initiation or exacerbation through the induction of aberrant immune responses in the absence of infection. Hidradenitis suppurativa (HS) is a complex, multifaceted disease involving the skin, innate and adaptive immunity, microbiota and environmental stimuli. Herein, we discuss the current state of HS skin microbiome research and how microbiome components may activate pattern recognition receptor (PRR) pathways, metabolite sensing pathways and antigenic receptors to drive antimicrobial peptide, cytokine, miRNA and adaptive immune cell responses in HS. We highlight the major open questions that remain to be addressed and how antibiotic therapies for HS likely influence both microbial burden and inflammation. Ultimately, we hypothesize that the two-way communication between the skin microbiome and host immune response in HS skin generates a chronic positive feed-forward loop that perpetuates chronic inflammation, tissue destruction and disease exacerbation.

The Microbiome in Hidradenitis Suppurativa: A Review

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic autoinflammatory skin disease. It is characterised by the development of abscesses and nodules in intertriginous anatomical sites. Whilst it is now recognised as an autoinflammatory condition rather than an infective disease, bacteria are implicated in disease pathogenesis.

METHODS

We performed a search of the literature from inception to 12 August 2020 using the search terms "hidradenitis suppurativa", "Verneuil's disease", "acne inversa", "microbiome", "bacteriology" and "microbiology". Studies were included if they assessed the cutaneous, gut or oral bacteria, bacteriology or microbiome in hidradenitis suppurativa.

RESULTS

Twenty-one studies examining the cutaneous microbiome and two studies examining the gastrointestinal microbiome in HS were identified. No studies examining the oral microbiome in HS were identified. A total of 972 patients and 46 healthy controls were included across studies examining the cutaneous microbiome. A total of 100 patients and 36 controls were included across both gut microbiome studies. Coagulase-negative Staphylococcus, anaerobes such as Porphyromonas and Prevotella, and Staphylococcus aureus species were commonly encountered organisms across the included cutaneous microbiome studies. The studies examining the gut microbiome were limited, with one small study demonstrating an alteration in the gut microbiome composition compared to controls. The other study found no alteration to the gut microbiome in patients with HS compared to those with inflammatory bowel disease (IBD) and HS, and IBD and/or psoriasis.

CONCLUSION

Research should be undertaken into the oral microbiome in HS. Further research should be undertaken examining the cutaneous and gut microbiome in HS, and its relationship with documented co-morbidities. Additionally, metagenomics-focused studies may help identify the relationship between microorganisms and host, and this may shed light on new pathways of disease pathogenesis. This may help identify potential future therapeutic targets.

A systematic review and critical appraisal of metagenomic and culture studies in hidradenitis suppurativa

Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic inflammatory skin disease with still largely unknown pathogenesis. While infectious organisms have been identified in lesions of the disease since the 1980s, questions remain over the role that bacteria and microbiome play. Recent studies using 16S ribosomal RNA gene sequencing and larger culture-based studies have begun to paint a clearer picture of the microbial world of HS. With this systematic review, we summarize all the work that has been done to date in HS bacteriology, analyse potential pitfalls and limitations of the current studies, and address future directions of investigation. This systematic review attempted to collate and analyse all bacteriology studies done to date. This review was prospectively registered with PROSPERO (1670769) performed in line with the PRISMA checklist. Twenty two studies were identified comprising 862 individual HS patients for culture studies and 206 HS patients for 16S rRNA gene sequencing studies. Methodology tended to be varied, with different sampling, culturing and sequencing methods as well as amount of analysis and stratification of patients. Bacteria identified as elevated in HS lesions in sequencing studies as well as grown from HS lesions in culture studies are identified and discussed. These primarily included the anerobic Gram-negative bacilli Prevotella, Porphyromonas and Fusibacterium, the Gram-positive bacilli Corynebacterium, and the Gram-positive cocci Staphylococcus, Streptococcus and Parvimonas. Potential interactions, as well as work in other disease models with related bacteria are also discussed. Areas of further investigation include in vitro studies of interactions between bacteria and keratinocytes, gut and oral microbiome studies and deep sequencing studies for virulence and phage factors.

Irrelevance of Panton-Valentine leukocidin in hidradenitis suppurativa: results from a pilot, observational study

Panton-Valentine leukocidin (PVL) appears to be a virulence factor which, among others, can exacerbate the pathogenicity of Staphylococcus aureus infections, especially inducing severe necrotic, deep-seated skin infections, abscesses, and recurrences. These peculiarities have some overlaps with hidradenitis suppurativa (HS). Our main aim was to assess if S. aureus producing PVL could have some role in influencing clinical features and/or course of HS, specifically in the suppuration and recurrence of lesions. This pilot, mono-centric, observational study included all adult subjects affected with HS consecutively referring to our HS clinic over a 3-month period. Clinically evident suppuration and at least 2 weeks wash out from any antibiotic were the main inclusion criteria. Purulent material from HS skin lesions was collected with swabs in order to isolate micro-organisms, with specific regard to S. aureus. Detection of PVL was performed by real-time quantitative PCR (RT-qPCR). We also analyzed purulent material from suppurative skin lesions other than HS, as a control. Thirty HS patients were included; 29 purulent lesions (96.7%) harbored at least one bacterial species. Five (16.7%) swab samples were positive for S. aureus, none of which was positive for PVL genes. Among the 30 purulent disorders included as controls, 8 (26.3%) were positive for S. aureus; of these, 4 strains (50%) expressed LPV. The study results seem to exclude the pathogenetic involvement of S. aureus producing PVL in HS; as a result, PVL does not seem to represent a potential target in the future development of HS treatments.

The Role of the Cutaneous Microbiome in Hidradenitis Suppurativa-Light at the End of the Microbiological Tunnel

The development of next generation sequencing, coupled with advances in bio-informatics, has provided new insights into the role of the cutaneous microbiome in the pathophysiology of a range of inflammatory skin diseases. In fact, it has even been suggested that the identification of specific skin microbial signatures may not only be useful in terms of diagnosis of skin diseases but they may also ultimately help inform personalised treatment strategies. To date, research investigating the role of microbiota in the development of inflammatory skin diseases has largely focused on atopic eczema and psoriasis vulgaris. The role of the microbiome in Hidradenits suppurativa (HS)-also known as acne inversa-a chronic auto-inflammatory skin disease associated with significant morbidity, has received comparatively little attention. This is despite the fact that antimicrobial therapy plays a central role in the treatment of HS. After briefly outlining the clinical features of HS and current treatment strategies, we move on to review the evidence of microbial dysbiosis in HS pathophysiology. We conclude by outlining the potential for metagenomic studies to deepen our understanding of HS biology but more importantly to identify novel and much needed treatment strategies.

Clinical Characteristics of Hidradenitis Suppurativa Patients from a Reference Centre in Kaunas, Lithuania

INTRODUCTION

Clinical data on hidradenitis suppurativa (HS) derived mainly from studies in Western Europe and the USA, raising the risk of potential selection bias. According to the official data, during 2006-2015 the incidence of HS in Lithuania was 23.5 cases per 100,000 population with a female-to-male ratio of 2:1. A more fine-grained data set would however be of great relevance to further understanding this disease. Collection of standardized data enables the comparison of populations of patients across samples.

OBJECTIVES

To present a cohort of HS patients with uniformly collected data according to European Hidradenitis Suppurativa Foundation/European Reference Network-Skin recommendations.

METHODS

The demographic and clinical data of a total of 37 HS patients, included over a 3-year period (from 2016 to January 2019) in a local database of the reference centre of Rare Skin Diseases in the Hospital of the Lithuanian University of Health Sciences Kauno Klinikos, were analysed. Non-parametric tests such as χ2 and Mann-Whitney were used for assessing interdependence between qualitative data. Logistic regression analysis was performed to find out the factors statistically related with significant diagnostic delay.

RESULTS

The mean duration of diagnosis delay was 5.5 (±5.9) years in females and 6.6 (±8.2) years in males. A significant delay (>2 years) was reported in 29/37 (78.4%) cases and was not related with sex, age at HS diagnosis or disease severity. The groin area was more affected in females than in males. There was no statistically significant difference between sex and Hurley stage, HS Physician Global Assessment, International Hidradenitis Suppurativa Severity Score System, visual analogue scale and Dermatology Life Quality Index scores. Combined (medical and surgery) HS treatment was applied to 46.0% and monotherapy (medical or surgery) to 54.0% of patients.

CONCLUSIONS

Standardized collection of epidemiological and clinical data is required to improve the quality of HS patient data and allow for international comparisons and pooling of data for research purposes.

Staphylococcus aureus Carriage Status in Patients with Hidradenitis Suppurativa: An Observational Cohort Study in a Tertiary Referral Hospital in Athens, Greece

BACKGROUND

Hidradenitis suppurativa (HS) is a chronic, recurrent, auto-inflammatory disease that affects the pilosebaceous unit in apocrine gland-bearing areas. Bacteria are thought to play a role in the development and progression of disease. In addition, antibiotics are frequently used as first-line management for HS. We sought to determine the carriage status of Staphylococcus aureus and its resistance to antibiotics among patients with HS in a tertiary referral hospital in Athens, Greece.

METHODS

In this observational cohort study, 68 consecutive patients attending the HS clinic of "Attikon" General University Hospital in Athens, Greece, during a 9-month period were enrolled. All patients had not received any antibiotic therapy for any reason during the previous 3 months before enrollment. Nasal and oropharyngeal samplingwere obtained, and specimens were tested for the presence of S. aureus.Antibiotic susceptibility testing was performed using the VITEK 2 system. Standard statistical tests, descriptive statistics tests, and χ2 and Pearson correlation tests were performed, using IBM SPSS Statistics 25.The level of significance was set at a pvalue <0.05.

RESULTS

Sixty-eight patients with HS were studied. There were 44 females (64.7%) and 24 males (35.3%). The mean age was 36.63 ± 13.0 (IQR = 21), and the mean age at onset of disease was 23.90 ± 11.53 (IQR = 14). The mean duration of disease was 12.74 ± 10.20 years (IQR = 15). Fifteen (22.1%) of the patients were Hurley stage I, 22 (32.4%) were Hurley stage II, and 31 (45.6%) were Hurley stage III. S. aureus carriage was detected in 17 patients (25%). Six of them (35.3%) had MRSA strains. There was an increased prevalence of S. aureus colonization (p = 0.058) and MRSA (p = 0.101) in Hurley stage III patients, but this result was not statistically significant.

CONCLUSIONS

We found a 25% prevalence of S. aureus colonization (17/68 patients) and a 35.3% prevalence of MRSA (6/17) among our HS patients. There was an increased prevalence of S. aureusand MRSA positivity in HS patients with Hurley stage III. Further studies are needed to clarify the possible clinical significance of S. aureus carriage in the disease development and progression as well as in the treatment outcome.

[Radical treatment of hidradenitis suppurativa: Comparison of the use of the artificial dermis and pedicled perforator flaps]

OBJECTIVES

The objective of this study was to compare the use of artificial dermal and perforator flap after radical surgery of severe axillary and perineal hidradenitis suppurativa disease.

PATIENTS AND METHODS

The data on postoperative outcomes, scar assessment (POSAS) and quality of life (DLQI, SF-36) were collected during consultation or by phone call. Forty-seven patients were included in our study between January 2015 and September 2017, including 27 patients in the artificial dermal group and 20 patients in the perforator flap group.

RESULTS

The quality of life assessment by the SF-36 questionnaire showed a significant increase in quality of life in both groups (P<0.05), higher in the perforating flap group (P<0.001). The DLQI questionnaire showed a decrease in the impact of MV on quality of life in both groups, which was greater in the perforator flap group (P<0.05). The scarring assessment by the POSAS patient and observer questionnaire showed a better overall opinion in the perforator flap group (P<0.001). In the perforator flap group, the total hospital stay and healing time was shorter (P<0.001) and the return to work was faster (P<0.001).

CONCLUSION

The artificial dermis and the perforator flaps are very useful coverage solutions after radical surgery of hidradenitis suppurativa. The use of perforator flaps, however, seems more interesting while simplifying the post-operative course.

Human Microbiome: Composition and Role in Inflammatory Skin Diseases

This review focuses on recent evidences about human microbiome composition and functions, exploring the potential implication of its impairment in some diffuse and invalidating inflammatory skin diseases, such as atopic dermatitis, psoriasis, hidradenitis suppurativa and acne. We analysed current scientific literature, focusing on the current evidences about gut and skin microbiome composition and the complex dialogue between microbes and the host. Finally, we examined the consequences of this dialogue for health and skin diseases. This review highlights how human microbes interact with different anatomic niches modifying the state of immune activation, skin barrier status, microbe-host and microbe-microbe interactions. It also shows as most of the factors affecting gut and skin microorganisms' activity have demonstrated to be effective also in modulating chronic inflammatory skin diseases. More and more evidences demonstrate that human microbiome plays a key role in human health and diseases. It is to be expected that these new insights will translate into diagnostic, therapeutic and preventive measures in the context of personalized/precision medicine.

Biofilm production and antibiotic susceptibility of Staphylococcus epidermidis strains from Hidradenitis Suppurativa lesions

BACKGROUND

An aberrant interaction between commensal skin bacteria and the host skin immune system is considered important in the pathogenesis of hidradenitis suppurativa (HS).

OBJECTIVE

In this study, we investigated the antibiotic susceptibility and biofilm-forming capabilities of S. epidermidis strains isolated from HS patients.

METHODS

Skin biopsies were taken from active HS lesions such as inflammatory nodules and/or sinuses and non-involved skin from 26 patients and cultured under optimal microbiological conditions for 24 h. Planktonic growth, biofilm production, antibiotic susceptibility and biofilm eradication by clindamycin, doxycycline, rifampicin and tetracycline were tested including a laboratory control strain of S. epidermidis for reference.

RESULTS

Staphylococcus epidermidis was cultured in 16 of 26 HS patients (62%). In total 27 different S. epidermidis isolates were identified; 16 (59%) from non-involved skin and 11 (41%) from HS lesions. All bacterial strains showed planktonic growth. Twenty-four of 27 (89%) isolates were strong biofilm producers in vitro. The biofilm-forming capability varied amongst the strains from non-involved skin and lesional skin. Twenty-four strains had an intermediate to resistant antibiotic susceptibility to clindamycin (89%). Rifampicin was the most effective antibiotic at inhibiting planktonic growth and at eradication of biofilm (P < 0.05).

CONCLUSION

We observed a slight increase in S. epidermidis virulence, characterized by resistance to commonly used antibiotics, increased biofilm production and resistance to biofilm eradication. In particular, the reduced sensitivity to tetracycline and clindamycin, two standard antibiotics in the treatment of HS, is alarming. Rifampicin, also important in HS treatment, showed the greatest efficacy at eradicating the biofilm at low MIC concentrations.

The Microbiological Landscape of Anaerobic Infections in Hidradenitis Suppurativa: A Prospective Metagenomic Study

Background

Hidradenitis suppurativa (HS) is a frequent and severe disease of the skin, characterized by recurrent or chronic skinfold suppurative lesions with a high impact on quality of life. Although considered inflammatory, antimicrobial treatments can improve or lead to clinical remission of HS, suggesting triggering microbial factors. Indeed, mixed anaerobic microbiota are associated with a majority of HS lesions. Our aim in this study was to characterize the landscape of anaerobic infections in HS using high-throughput sequencing.

Methods

We sampled and cultured 149 lesions and 175 unaffected control skinfold areas from 65 adult HS patients. The microbiome of 80 anaerobic lesions was compared to that of 88 control samples by 454 high-throughput sequencing after construction of 16S ribosomal RNA gene libraries.

Results

Bacterial cultures detected anaerobes in 83% of lesions vs 53% of control samples, combined with milleri group streptococci and actinomycetes in 33% and 26% of cases, respectively. High-throughput sequencing identified 43 taxa associated with HS lesions. Two gram-negative anaerobic rod taxa, Prevotella and Porphyromonas, predominated, contrasting with a reduced abundance of aerobic commensals. These rare taxa of normal skinfold microbiota were associated with lesions independently of gender, duration and familial history of HS, body mass index, and location. Two main additional taxa, Fusobacterium and Parvimonas, correlated with the clinical severity of HS.

Conclusions

In this study we reveal the high prevalence and particular landscape of mixed anaerobic infection in HS, paving the way for rationale targeted antimicrobial treatments.

The Follicular Skin Microbiome in Patients With Hidradenitis Suppurativa and Healthy Controls

Importance

Although the pathogenesis of hidradenitis suppurativa (HS) remains enigmatic, several factors point to potential involvement of the cutaneous microbiome. Insight into the cutaneous microbiome in HS using next-generation sequencing may provide novel data on the microbiological diversity of the skin.

Objective

To investigate the follicular skin microbiome in patients with HS and in healthy controls.

Design, Setting, and Participants

This case-control study obtained punch biopsy specimens from patients with HS (lesional and nonlesional) and healthy controls between October 1, 2014, and August 1, 2016. Data were analyzed from March to November 2016. Patients with HS were recruited from the Department of Dermatology, Zealand University Hospital, Roskilde, Denmark. Biopsy specimens were analyzed at the Department of Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark. None of the participants received any antibiotics (systemic or topical therapy) within 1 month before the study. In patients with HS, biopsy specimens were obtained from lesional skin (axilla or groin) and nonlesional skin. Only nodules containing at least 1 visible hair follicle were biopsied. Biopsy specimens from healthy controls were obtained from the axilla only.

Main Outcomes and Measures

The different microbiomes were investigated using next-generation sequencing targeting 16S and 18S ribosomal RNA.

Results

The skin microbiome was characterized in 30 patients with HS (mean [SD] age, 46.9 [14.0] years; 19 [63% female]) and 24 healthy controls (mean [SD] age, 32.2 [12.0] years; 13 [54% female]). The next-generation sequencing data provided a previously unreported (to our knowledge) characterization of the skin microbiome in HS. The study demonstrated that the microbiome in HS differs significantly from that in healthy controls in lesional and nonlesional skin. Overall, the following 5 microbiome types were identified: Corynebacterium species (type I), Acinetobacter and Moraxella species (type II), Staphylococcus epidermidis (type III), Porphyromonas and Peptoniphilus species (type IV), and Propionibacterium acnes (type V). In lesional skin, microbiome types consisted predominantly of type I or type IV. Microbiome type IV was not detected in healthy controls. Several taxa, including Propionibacterium, showed a significantly higher relative abundance in healthy controls vs HS skin, indicating that Propionibacterium may be part of the pathogenesis in HS.

Conclusions and Relevance

The study findings suggest a link between a dysbiotic cutaneous microbiome and HS.

The critical role of macrophages in the pathogenesis of hidradenitis suppurativa

INTRODUCTION

Hidradenitis suppurativa (HS) is a painful chronic inflammatory disease with a prevalence between 1 and 4% of general population. The pathogenesis of HS long eluded scientists, but growing evidence suggests that it is a consequence of inflammatory dysregulation.

FINDINGS

Recent studies suggest that dysregulated immune response to skin flora and overexpression of inflammatory cytokines leads to chronic skin inflammation seen in HS. Macrophages are the most numerous inflammatory cells found in HS infiltrates and release numerous pro-inflammatory cytokines such as IL-23, and IL-1β and TNF-α, exacerbating the inflammation and contributing to the pathogenesis of HS. Furthermore, in HS, there is dysregulated function of other immune players closely associated with macrophage function including: matrix metalloproteases (MMP) 2 and 9 overexpression, toll-like receptor upregulation, impaired Notch signalling, NLRP3 inflammasome upregulation, and dysregulated keratinocyte function. Lifestyle factors including obesity and smoking also contribute to macrophage dysfunction and correlate with HS incidence.

CONCLUSIONS

The overexpression of pro-inflammatory cytokines and subsequent efficacy of anti-cytokine biologic therapies highlights the importance of managing macrophage dysfunction. Future therapies should target key molecular drivers of macrophage dysfunction such as TLR2 and NLRP3 overexpression.

Medical and Surgical Treatment of Hidradenitis Suppurativa: A Review

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease presenting with painful nodules, abscesses, sinus tracts, and scarring primarily affecting apocrine gland-rich intertriginous areas. HS prevalence ranges from 0.05 to 1%. The central pathogenic event in HS is believed to be the occlusion of the upper part of the folliculopilosebaceous unit, leading to the rupture of the sebofollicular canal with the consequent development of perifollicular lymphohistiocytic inflammation. The HS treatment choices are influenced by disease severity and its individual subjective impact, involving both medical and surgical interventions. However, given the chronic nature of HS, its destructive impact on social, working, and daily life of patients, its management is often frustrating for both the patient and physician. Hence, prompt and effective management strategies are urgently needed and a multidisciplinary approach is advocated. Therefore, in this article, we highlighted the main features of HS (clinical aspects, epidemiology, pathogenesis, diagnostic criteria, classifications, comorbidities, and treatments), so that awareness of this disease might be heightened in primary care physicians and surgeons, who may be the first health care providers to see patients with this disease owing to its characteristic clinical presentation (inflammatory nodules, abscesses, sinus tract, etc.).

Bacterial biofilm in chronic lesions of hidradenitis suppurativa

BACKGROUND

Chronic nonhealing or recurrent inflammatory lesions, reminiscent of infection but recalcitrant to antibiotic therapy, generally characterize biofilm-driven diseases. Chronic lesions of hidradenitis suppurativa (HS) exhibit several characteristics, which are compatible with well-known biofilm infections.

OBJECTIVES

To determine and quantify the potential presence of bacterial aggregates in chronic HS lesions.

METHODS

In 42 consecutive patients with HS suffering from chronic lesions, biopsies were obtained from lesional as well as from perilesional skin. Samples were investigated using peptide nucleic acid-fluorescence in situ hybridization in combination with confocal laser scanning microscopy. In addition, corresponding histopathological analysis on haematoxylin and eosin slides was performed.

RESULTS

Biofilms were seen in 67% of the samples of chronic lesions and in 75% of the perilesional samples. The mean diameter of aggregates in lesional skin was significantly greater than in perilesional skin (P = 0·01). Large biofilms (aggregates > 50 μm in diameter) were found in 42% of lesional samples and in only 5% of the perilesional samples (P = 0·009). The majority of the large biofilms were situated in sinus tracts (63%) or in the infundibulum (37%). The majority of the sinus tract samples (73%) contained active bacterial cells, which were associated with inflammation.

CONCLUSIONS

This study suggests that biofilm formation is associated with inflammation of chronic HS lesions. The aggregates most likely occur as a secondary event, possibly due to predisposing local anatomical changes such as sinus tracts (tunnels), keratinous detritus and dilated hair follicles.

An Update on Medical Treatment Options for Hidradenitis Suppurativa

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease characterized by recurrent inflammatory nodules mostly located in the armpits and groin. Over the years multiple treatments for HS have been proposed; however, to date a cure is still lacking. In this update we provide an overview of most drug treatments reported on for HS, where possible with their mode of action and side effects. In mild cases, clindamycin lotion or resorcinol cream have proven effective. Tetracyclines are a first-line systemic option in more widespread or severe cases, followed by the combination of clindamycin and rifampicin. However, the recurrence rate is high after discontinuation of clindamycin plus rifampicin combination therapy. Long-term treatment with retinoids, especially acitretin is feasible, although teratogenicity has to be taken into account in females of reproductive age. Multiple anti-inflammatory drugs have been suggested for HS, such as dapsone, fumarates or cyclosporine. However, their effectiveness in HS is based on small case series with varying results. If most common treatments have failed, biologics (e.g., infliximab or adalimumab) are the next step. Although not addressed in this review, surgical interventions are often needed to achieve remission.

The Microbiology of Hidradenitis Suppurativa

Although the clinical presentation of Hidradenitis Suppurativa (HS) is strongly reminiscent of bacterial infection, the role of bacteria remains controversial. Studies have isolated an array of different bacterial specimens as well as biofilm formation in lesional HS skin. Consistent findings of Gram-positive cocci and -rods including Staphylococus aureus, Coagulase-negative staphylococci (CoNS) and Corynebacterium species (spp) in deep tissue samples have been demonstrated in HS. Although efficacy of antibiotics, i.e., rifampicin, clindamycin or tetracycline may support a microbial role in disease pathogenesis, the most often isolated bacterial specimens are commensal bacteria (CoNS).

Hidradenitis Suppurativa

Background:

Hidradenitis suppurativa is a clinically defined disease that causes considerable morbidity for patients. The results of recent studies, which have increased the understanding of this disease, are reviewed.

Objective:

The epidemiology, risk factors, pathogenesis, and treatment of this disease are summarized to help clinicians with practical patient management.

Conclusion:

Hidradenitis suppurativa remains a clinical challenge to patients and physicians alike. Physicians should be familiar with the impact this disease has on the patient and with the range of treatments available. Use of simple incisions as treatment is strongly discouraged. Additional pathogenic as well as therapeutic studies are necessary.

Hydradenitis suppurativa and inflammatory bowel disease: An unusual, but existing association

Inflammatory bowel disease (IBD) could be associated with several extra-intestinal manifestations (EIMs) involving musculoskeletal, hepatopancreatobiliary, ocular, renal, and pulmonary systems, as well as the skin. In the last years, hidradenitis suppurativa (HS) is acquiring an increasing interest. IBD, especially Crohn's disease (CD), is among the most reported associated diseases in HS patients. The aim of this paper is to give a brief overview of data showing a possible epidemiologic and pathogenetic association between IBD and HS. We performed a pooled-data analysis of four studies and pooled prevalence of HS in IBD patients was 12.8%, with a 95%CI of 11.7%-13.9%. HS was present in 17.3% of subjects with CD (95%CI: 15.5%-19.1%) and in 8.5% of UC patients (95%CI: 7.0%-9.9%). Some items, especially altered immune imbalance, are generally involved in IBD pathogenesis as well as invoked by HS. Smoking is one of the most relevant risk factors for both disorders, representing a predictor of their severity, despite, actually, there being a lack of studies analyzing a possible shared pathway. A role for inheritance in HS and CD pathogenesis has been supposed. Despite a genetic susceptibility having been demonstrated for both diseases, further studies are needed to investigate a genetic mutual route. Although the pathogenesis of IBD and HS is generally linked to alterations of the immune response, recent findings suggest a role for intestinal and skin microbiota, respectively. In detail, the frequent finding of Staphylococcus aureus and coagulase-negative staphylococci on HS cutaneous lesions suggests a bacterial involvement in disease pathogenesis. Moreover, microflora varies in the different cutaneous regions of the body and, consequently, two different profiles of HS patients have been identified on these bases. On the other hand, it is well-known that intestinal microbiota may be considered as "the explosive mixture" at the origin of IBD despite the exact relationship having not been completely clarified yet. A better comprehension of the role that some bacterial species play in the IBD pathogenesis may be essential to develop appropriate management strategies in the near future. A final point is represented by some similarities in the therapeutic management of HS and IBD, since they may be controlled by immunomodulatory drugs. In conclusion, an unregulated inflammation may cause the lesions typical of both HS and IBD, particularly when they coexist. However, this is still a largely unexplored field.

Bacterial pathogens associated with hidradenitis suppurativa, France

Hidradenitis suppurativa (HS) is a skin disease characterized by recurrent nodules or abscesses and chronic suppurating lesions. In the absence of clear pathophysiology, HS is considered to be an inflammatory disease and has no satisfactory medical treatment. Recently, prolonged antimicrobial treatments were shown to improve or resolve HS lesions. We prospectively studied the microbiology of 102 HS lesions sampled from 82 patients using prolonged bacterial cultures and bacterial metagenomics on 6 samples. Staphylococcus lugdunensis was cultured as a unique or predominant isolate from 58% of HS nodules and abscesses, and a polymicrobial anaerobic microflora comprising strict anaerobes, milleri group streptococci, and actinomycetes was found in 24% of abscesses or nodules and in 87% of chronic suppurating lesions. These data show that bacteria known to cause soft tissue and skin infections are associated with HS lesions. Whether these pathogens are the cause of the lesions or are secondary infectious agents, these findings support targeted antimicrobial treatment of HS.

Recalcitrant Hidradenitis Suppurativa: An Investigation of Demographics, Surgical Management, Bacterial Isolates, Pharmacologic Intervention, and Patient-reported Health Outcomes

Hidradenitis suppurativa (HS) is characterized by chronic inflammation, recurrent abscesses, and scarring. Surgery is performed when medical management and antibiotic therapy fails. This study sought to evaluate the demographics, surgical procedures, bacteriology, pharmacologic intervention, and quality of life of patients with recalcitrant HS requiring surgical intervention. A retrospective chart review was performed of 76 recalcitrant HS patients at the University of Illinois Medical Center. Patient demographics, bacterial culture, and surgery data were reviewed. Quality of life was assessed using the 36-item short-form health survey. Patients were mostly female (73.7%) and African American (81.6%) with a mean duration of symptoms of 8.6 years before surgery. Patients underwent at least one surgical procedure, most often to the axillae (57.6%) and 73.7 per cent received antibiotics. The most common culture isolates were Corynebacterium species (14.0%), Staphylococcus epidermidis (13.1%), and Staphylococcus aureus (10.4%) with varying resistance patterns. Surveyed patients had depressed 36-item short-form health survey physical functioning and social functioning scores. Recalcitrant HS patients with progressive symptomology over approximately nine years before surgical intervention were more likely to be African American women with axillary HS. Quality of life was diminished. We recommend initial treatment of HS with clindamycin and trimethoprim–sulfamethoxazole in clindamycin refractory cases.

Bacteriology of hidradenitis suppurativa/acne inversa: A review

Given that follicular papules and pustules, as well as nodules and abscesses, are the clinical hallmarks of hidradenitis suppurativa (HS), an infectious, bacterial pathway has been suspected in the pathogenesis of this chronic, inflammatory condition. Elucidating the behavior and role of bacterial species in HS and their interaction with cutaneous innate immunity will provide more insight into the pathophysiology of this condition. This review of prospective investigations suggests a synergistic relationship between impaired innate immunity and microbial factors in the etiology of HS.

Hidradenitis Suppurativa: A Guide for the Practicing Physician

Hidradenitis suppurativa is a chronic inflammatory disease of apocrine gland-bearing skin. Although immunologic derangements, genetic predisposition, obesity, and smoking are likely important factors, the pathogenesis of the disease and the effect of available treatments on disease course have not been fully elucidated. In the absence of proper treatment, chronic inflammation results in diffuse scarring and a wide array of complications, including the development of cutaneous squamous cell carcinoma. This severe and chronic disease can have detrimental effects on self-esteem and quality of life. No ideal treatment regimen has been defined, but several therapies have been found to reduce lesion severity and improve symptoms. We reviewed the literature through July 2014 for existing treatments. Published articles were obtained via systematic review of medical databases (PubMed, Embase, Google Scholar) and scrutiny of citation lists using the search terms "hidradenitis suppurativa" and "acne inversa". Given the scarce literature on treatment strategies, we also reviewed data from any case reports or prospective and retrospective studies that were located. On the basis of the existing literature, we provide an evidence-based algorithm for the management of this disease in the primary care setting. More research is needed to evaluate the comparative effectiveness of topical and systemic treatments and to better understand the pathogenesis, natural history, and subtypes of hidradenitis suppurativa.

The bacteriology of hidradenitis suppurativa: a systematic review

Hidradenitis suppurativa (HS) is a chronic inflammatory disabling skin disease consisting of recurrent nodules, sinuses, fistulas and scarring involving the intertriginous regions. HS is often a therapeutic challenge and most treatments are off-label. A better understanding of aetiology and pathogenesis of HS may facilitate the development of effective treatment. Although the clinical presentation is strongly reminiscent of bacterial infection, the role of bacteria remains controversial. Studies have isolated an array of different bacteria specimens. Consistent findings of Gram-positive cocci and Gram-positive rods including Staphylococus aureus, coagulase-negative staphylococci (CoNS) and Corynebacterium species in deep tissue samples have been demonstrated in HS and may constitute a central target for the immune system. Efficacy of antibiotics, that is rifampicin, clindamycin or tetracycline, supports a microbial role in disease pathogenesis. However, these antibiotics also work as immunomodulators of especially T cells, and the underlying mechanisms may therefore be more complex. We performed a systematic review of previous studies investigating the bacterial flora in hidradenitis suppurativa. We searched PubMed, EMBASE, Royal Danish Library and Cochrane library (search date 11 December 2014). A total of 66 papers were identified and nine papers published between 1988 and 2014 matched our inclusion criteria, yielding bacteriological data of a total of 324 patients with HS (mean age 36.8 years and female/male ratio 215/109). This overview of the bacteriology may aid researchers and physicians exploring the potential role of bacteria in HS. Furthermore, to stimulate a broader debate, we also present different viewpoints on the possible role of bacteria in HS.

Hidradenitis Suppurativa and Wound Management

Hidradenitis suppurativa (HS) is a chronic, burdensome, debilitating disease of the hair follicle. It presents with recurrent painful inflamed and noninflamed lesions usually in specific body areas such as axillary, inguinal, perineal, and genital areas. It is associated with a large range of other diseases and conditions, such as obesity, arthropathy, inflammatory bowel diseases, and sqaumous cell carcinoma. Medical therapy may be systemic or topical, mainly based on antibiotics, retinoids, hormones and immunosuppressive drugs, including biological therapies. Surgical and laser therapies may be a valid therapeutic approach in order to treat locally recurring lesions. The aim of this article is to review the wound healing options after skin excision and laser treatments, with a focus on lesions left to heal by secondary intention, analyzing the efficacy of moist wound dressings, negative pressure wound therapy, bioactive dressings, such as platelet-rich plasma gel and hylarunoic acid scaffold, or autologous keratinocyte suspension in platelet concentrate and skin-grafting tecniques.

Aerobic and Anaerobic Bacteriology of Hidradenitis Suppurativa: A Study of 22 Cases

INTRODUCTION

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease of unclear etiology. The role of bacteria in the pathogenesis of disease remains controversial.

MATERIALS AND METHODS

Specimens were obtained from 22 HS patients by direct percutaneous needle aspiration. The collected material was cultured in aerobic and anaerobic conditions, and sensitivity tests were performed.

RESULTS

Of the 22 patients, 32% were culture negative and 68% were culture positive. A total of 16 isolates was obtained, 14 aerobic and 2 anaerobic. Aerobic bacteria were present in 86% of the specimens, whereas only anaerobic bacteria were isolated in 7%. The predominant aerobic species were Proteus mirabilis, Staphylococcus haemolyticus and Staphylococcus lugdunensis. The isolated anaerobic bacteria were Dermacoccus nishinomiyaensis and Propionibacterium granulosum.

CONCLUSION

A variety of aerobic and anaerobic bacteria was isolated from the HS lesions of our patients. In contrast to previous studies, fewer patients were found to be culture positive, and Staphylococcus aureus was isolated in only 1 of them. More studies are necessary to elucidate the controversial role of bacteria in the pathogenesis of HS.

The medical and laser management of hidradenitis suppurativa

Hidradenitis suppurativa (HS) is a chronic, debilitating skin disease characterized by painful recurrent nodules and abscesses. In advanced stages, sinus tracts form, with resulting fibrotic and cribriform scar formation, leading to dermal contractures and induration of the affected skin. The epidemiology of HS is poorly described, and few population-based studies exist. The reported incidence varies from 0.0003 to 4%. Effective treatment options for HS are limited, and randomized controlled trials addressing the safety and/or efficacy of available treatments are scarce. No medical treatment to date has been approved by the US FDA specifically for the treatment of HS. While some evidence of disease improvement exists with agents including clindamycin and rifampicin, metformin, fumarates, infliximab, and adalimumab, no single treatment has shown overwhelmingly positive outcomes. The lack of randomized controlled trials for most treatments and often disappointing treatment outcomes is disheartening. This study reviews the published evidence for treatment options for HS.

European S1 guideline for the treatment of hidradenitis suppurativa/acne inversa

Hidradenitis suppurativa/acne inversa (HS) is a chronic, inflammatory, recurrent, debilitating skin disease of the hair follicle that usually presents after puberty with painful, deep-seated, inflamed lesions in the apocrine gland-bearing areas of the body, most commonly the axillae, inguinal and anogenital regions. A mean disease incidence of 6.0 per 100,000 person-years and an average prevalence of 1% has been reported in Europe. HS has the highest impact on patients' quality of life among all assessed dermatological diseases. HS is associated with a variety of concomitant and secondary diseases, such as obesity, metabolic syndrome, inflammatory bowel disease, e.g. Crohn's disease, spondyloarthropathy, follicular occlusion syndrome and other hyperergic diseases. The central pathogenic event in HS is believed to be the occlusion of the upper part of the hair follicle leading to a perifollicular lympho-histiocytic inflammation. A highly significant association between the prevalence of HS and current smoking (Odds ratio 12.55) and overweight (Odds ratio 1.1 for each body mass index unit) has been documented. The European S1 HS guideline suggests that the disease should be treated based on its individual subjective impact and objective severity. Locally recurring lesions can be treated by classical surgery or LASER techniques, whereas medical treatment either as monotherapy or in combination with radical surgery is more appropriate for widely spread lesions. Medical therapy may include antibiotics (clindamycin plus rifampicine, tetracyclines), acitretin and biologics (adalimumab, infliximab). A Hurley severity grade-relevant treatment of HS is recommended by the expert group following a treatment algorithm. Adjuvant measurements, such as pain management, treatment of superinfections, weight loss and tobacco abstinence have to be considered.

Microbiology of hidradenitis suppurativa (acne inversa): a histological study of 27 patients

Hidradenitis suppurativa (acne inverse) (HS) is a chronic skin disease primarily affecting hair follicles. The aetiology of HS is unknown, but infection is believed to play some role. This retrospective study investigated the microbial colonization directly in skin appendices in HS skin samples. Archival samples from 27 patients with HS were screened by immunofluorescence labelling with monoclonal and polyclonal antibodies against Gram-positive bacteria, Propionibacterium acnes and Propionibacterium granulosum. Fluorescence in situ hybridization was used for further species identification of Staphylococcus spp. Overall, 17 patients (63%) were found positive for bacterial colonization. Of these, 15 showed colonization in hair follicles and/or sinus tracts. The most commonly identified bacteria were DAPI labelled coccoids that were seen in 71% of the positive patients in the form of biofilms and microcolonies. P. acnes was found as biofilms in hair follicles of two patients. Staphylococcus aureus and coagulase-negative staphylococci were not detected in any sample. The results of this study indicate a common bacterial presence in HS skin lesions. Bacterial biofilms are not uncommon and their pathogenic role needs further evaluation.

Hidradenitis suppurrativa (acne inversa) as a systemic disease

Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic follicular occlusive skin disorder characterized by recurrent abscesses, draining sinuses, and scarring, with a multifactorial pathogenesis. The answer to the question whether HS may be considered a systemic disease relies on the presence of accompanying systemic manifestations, on the proof of association with other diseases or conditions, and on the occurrence of systemic implications. We address these questions based on a systemic review of the existing literature. There are several reports in the literature of the coexistence of HS with other diseases, including pyoderma gangrenosum, PASH syndrome, Adamantiades-Behcet's disease, spondylarthropathy, Crohn's disease, SAPHO, pachyonychia congenita, Dowling-Degos disease, and the keratitis-ichthyosis-deafness (KID) syndrome. Case series exist only for Crohn's disease, while most other reports are anecdotal, thus, not providing high-quality scientific evidence. Based on well-designed studies, HS has been associated with the metabolic syndrome and with excess body weight or obesity. The link between HS and systemic associations may be attributed to common genetic or environmental factors or shared inflammatory pathways.

Acne inversa goes an extra mile than hidradenitis suppurativa

Acne inversa (AI, hidradenitis suppurativa, Velpeau’s disease, Verneuil’s disease) is a severe, chronic inflammatory dermatosis of unknown etiology, detected on the basis of clinical symptoms more frequently in women than in men. Purulent lesions in the form of nodules and inflammatory tumors, fistulas and scars are present in the areas with hair follicles and apocrine glands, most commonly on the armpits, groin, around the anus and pubic region. Acne inversa can lead to physical and mental disorders. Unfortunately, it is often misdiagnosed and ineffectively treated. The paper presents a case of a 46-year-old patient who was successfully treated surgically for AI around the anus and buttocks by excision of the changes and closure of the wound with local flaps and split-thickness skin grafts, taken with dermatome from the rear surface of the thighs. Surgical treatment is the method of choice in the treatment of severe AI.

Identification of three hidradenitis suppurativa phenotypes: latent class analysis of a cross-sectional study

To identify the underlying subtypes of hidradenitis suppurativa (HS), we performed latent class analysis on prospective clinical data of 618 consecutive patients seen between 2002 and 2010. The median patient age was 31 years (Q1=26; Q3=38), median age at HS onset was 20 years (16-25), and median Sartorius score was 18 (11-19); 34.4% of patients were of Hurley stage II or III. A three-class model showed the best fit. Latent class 1 (LC1) patients (48%) had a high probability of breast and armpit lesions (0.74) and hypertrophic scars (0.41). LC2 patients (26%) had a high probability not only of breast and armpit lesions (0.96) but also of lesions in the ears, chest, back, or legs (0.55); follicular lesions (pilonidal sinus: 0.48; comedones: 0.74); severe acne (0.47); and a family history of HS (0.44). Compared with LC1 patients, LC2 patients were more often male (odds ratio, 4.6; 95% confidence interval, 3-7; P<0.001) and current smokers (2.2; 1.3-3.9; P=0.005), and had greater disease severity (odds ratio, 1.6; 1.3-1.9; P<0.001). LC3 was characterized by gluteal involvement (0.54), papules, and folliculitis (0.71). LC3 patients were less often obese (0.6; 0.3-0.95; P=0.03) and had less severe disease (0.9; 0.7-1.1; P<0.001). These three phenotypes ("axillary-mammary", "follicular", and "gluteal") may help stratify patients for clinical trials.

Hidradenitis suppurativa: viewpoint on clinical phenotyping, pathogenesis and novel treatments

Hidradenitis suppurativa (HS) is an inflammatory, debilitating follicular skin disease with recurring flare-ups. The painful, deep-seated, inflamed lesions in the inverse areas of the body cause severe discomfort, and hence, serious psycho-social and economic costs. HS is common, but often misdiagnosed and mechanistically poorly understood. Furthermore, HS is notoriously difficult to treat resulting in a high unmet medical need. To provoke debate, rational experimentation and initiate strategic studies, we here present a concise viewpoint on seven topics: the diagnosis of HS, the role of mechanical friction, the critical importance of accurate clinical subgrouping, smoking and obesity, the role of bacteria, and our comprehensive view on HS pathogenesis with a central role for keratin clearance, and novel treatment approaches.

Is mechanical stress an important pathogenic factor in hidradenitis suppurativa?

Hidradenitis suppurativa (HS) is a chronic of recurrent, inflammatory, follicular disease that usually presents after puberty with painful deep-seated, inflamed lesions in the inverse skin areas of the body. It has been hypothesized that mechanical pressure or friction is a risk factor for HS. We describe the case of a man with a lower leg amputation who presented HS-like lesions on his leg stump after wearing a leg prosthesis. Although pilonidal sinus-like disease could not be excluded, we diagnosed him with HS-like lesions, induced by prosthesis-related friction. We argue that this case supports the concept that mechanical friction and a warm humid microclimate by occlusion contribute to HS development.

Bacteriology of hidradenitis suppurativa exacerbations and deep tissue cultures obtained during carbon dioxide laser treatment

BACKGROUND

Previous studies have shown different bacteria in hidradenitis suppurativa (HS) lesions, but the literature regarding bacteria in acute exacerbation of HS is sparse.

OBJECTIVES

To determine the type of bacteria isolated from HS lesions during exacerbations of the disease.

METHODS

Patients with HS with acute nodules or abscesses were examined and treated by carbon dioxide laser vaporization. Bacterial samples for aerobic and anaerobic cultures were taken from the skin surface (before surgery) and then from the deeper layers (during surgery) of the lesions. At each level two samples were taken, one with a punch biopsy and one by pressing a soft agar gel against the skin. The bacterial findings were typed and quantified.

RESULTS

A total of 10 patients (eight women and two men), with a mean age of 37·2 years and a mean HS duration of 14·5 years, were included. All of them had an ongoing exacerbation (mean duration 5·6 days) of their HS, with one inflamed lesion that was treated by carbon dioxide laser vaporization. Coagulase-negative staphylococci (CNS) were found in the deep layers in all 10 patients. Nine of the patients carried Corynebacterium spp. and two alpha-haemolytic streptococci at various levels. Among the anaerobic microorganisms, Gram-positive cocci were the most common bacteria.

CONCLUSIONS

As found in a previous study, CNS were the most common bacteria, but contrary to what we expected, Staphylococcus aureus was not found in any cultures from acute inflammatory nodules of HS exacerbations.