Pyogenic Arthritis, Pyoderma Gangrenosum, Acne, Suppurative Hidradenitis (PA-PASH) Syndrome: An Atypical Presentation of a Rare Syndrome

Can telomeric changes orchestrate the development of autoinflammatory skin diseases?

Telomeres, the safeguarding caps at the tips of chromosomes, are pivotal in the aging process of cells and have been linked to skin ailments and inflammatory conditions. Telomeres undergo a gradual reduction in length and factors such as oxidative stress hasten this diminishing process. Skin diseases including inflammatory conditions can be correlated with the shortening of telomeres and the persistent activation of DNA damage response in skin tissues. Telomere dysfunction could disrupt the balance of the skin, impairs wound healing, and may contribute to abnormal cytokine production. Skin aging and processes related to telomeres may function as one of the triggers for skin diseases. The presence of proinflammatory cytokines and dysfunctional telomeres in conditions such as Dyskeratosis Congenita implies a possible connection between the shortening of telomeres and the onset of chronic inflammatory skin disorders. In autoinflammatory skin diseases, chronic inflammation hinders wound healing thus aggravating the progression of the disease. The NF-ĸB pathway might contribute to the initiation or progression of chronic disorders by influencing mechanisms associated with telomere biology. The intricate connections between telomeres, telomerase, telomere-associated proteins, and skin diseases are still a complex puzzle to be solved. Here, we provide an overview of the impact of telomeres on both health and disease with a specific emphasis on their role in skin, inflammation and autoinflammatory skin disorders.

Hidradenitis Suppurativa-Related Autoinflammatory Syndromes: An Updated Review on the Clinics, Genetics, and Treatment of Pyoderma gangrenosum, Acne and Suppurative Hidradenitis (PASH), Pyogenic Arthritis, Pyoderma gangrenosum, Acne and Suppurative Hidradenitis (PAPASH), Synovitis, Acne, Pustulosis, Hyperostosis and Osteitis (SAPHO), and Rarer Forms

Hidradenitis suppurativa (HS) is an autoinflammatory skin disorder of the terminal hair follicle, which can present in sporadic, familial, or syndromic form. A classification has been proposed for the latter, distinguishing cases associated with a known genetic condition, with follicular keratinization disorders or with autoinflammatory diseases. This review focuses on the clinical and genetic features of those entities (ie, pyoderma gangrenosum [PG], acne and HS; PG, acne, pyogenic arthritis and HS; psoriatic arthritis, PG, acne and HS; synovitis, acne, pustulosis, hyperostosis, osteitis; and so forth) for which the collective term HS-related autoinflammatory syndromes is proposed.

Genetic mutations in pyoderma gangrenosum, hidradenitis suppurativa, and associated autoinflammatory syndromes: Insights into pathogenic mechanisms and shared pathways

Pyoderma gangrenosum (PG), hidradenitis suppurativa (HS), and the associated autoinflammatory syndromes, including pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome, PSTPIP1-associated myeloid-related proteinemia inflammatory (PAMI) syndrome, pyoderma gangrenosum, acne, and hidradenitis suppurativa (PASH) syndrome, and pyogenic arthritis, pyoderma gangrenosum, acne, and suppurative hidradenitis (PAPASH) syndrome are dermatological conditions characterized by chronic inflammation and tissue damage. Recent advances in genetic research have identified specific mutations associated with these disorders, shedding light on their underlying pathogenic mechanisms. This review aims to summarize the current knowledge of identified mutations and presumed pathophysiology in PG, HS, and the associated autoinflammatory syndromes.

Hidradenitis suppurativa: Detangling phenotypes and identifying common denominators

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease with a severe impact on patients' quality of life through its recurrent and painful nature, as well as its comorbidity burden. The shift in the pathogenic paradigm from a condition of the apocrine glands to an autoinflammatory disease associated with follicular destruction has rendered its understanding difficult, as there are still large gaps in pinpointing the underlying mechanisms, which cannot currently explain the existing clinical variation and as a result, translate into suboptimal therapy. Multifactorial involvement is hypothesized, with an implication of genetic mutations, microbiome dysbiosis, cytokine upregulation and environmental factors. Clinical observation is fundamental for diagnosis, however, the marked heterogeneity in presentation leads to delays in detection and challenges in treatment selection, showcasing clear limits in defining the link between genetic aspects of HS, the role of epigenetic factors and its pathogenic pathways. There have been attempts to formulate phenotypes that could aid in prognostication and management, however, current classification schemata show significant overlap and no validation through longitudinal studies. In this context, nomenclature poses a great challenge due to the lack of global agreement in the definition of lesions, which should be addressed by future research to enable simplified recognition and allow for more precise severity scoring. This could be complemented by the addition of extra dermatologic findings or paraclinical assessment in constructing phenotypes. The development of valid, predictive and reliable classifications of HS may lead to an improvement in comprehending its pathophysiology, favouring a more personalized approach in management. This could be achieved through consensus in the characterization of clinical features and data gathering, as well as validation attempts for described phenotypes. Ultimately, the genotype-endotype-phenotype correlation in HS requires targeted, systematic inquiries and should be addressed more largely to broaden the perspective on this debilitating entity.

Autoinflammatory syndromes

Autoinflammatory syndromes are a steadily growing group of inflammatory diseases caused by abnormal regulations of the innate immune system. The clinical presentation is multifaceted, but recurrent fever, skin involvement, joint inflammation and other systemic symptoms of inflammation are characteristic. In contrast to classic autoimmune diseases, autoantibodies or specific T cells are not involved in the pathogenesis. In fact, innate immunity plays the most important role in autoinflammation. While activation of the innate immune system is usually self-limiting in healthy individuals, mutations and dysregulation can lead to chronic and excessive activation of innate immune responses and to the development of autoinflammatory diseases.

A case of myeloperoxidase-antineutrophil cytoplasmic antibody and anticardiolipin antibody-positive pyogenic arthritis, pyoderma gangrenosum, acne and hidradenitis suppurativa (PAPASH) syndrome with colitis

A previous case report of colitis and serine proteinase 3-antineutrophil cytoplasmic antibody positivity in pyogenic arthritis, pyoderma gangrenosum (PG), acne and hidradenitis suppurativa (PAPASH) syndrome with colitis has been published. Herein, we report a similar case of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) positivity. A 26-year-old man presented with recurrent aseptic pyogenic arthritis, acne, hidradenitis suppurativa and PG. Lower gastrointestinal endoscopy was performed, and colitis was observed. No PSTPIP1 gene mutation was found in the gene-sequencing test. Based on these findings and prior case reports, we diagnosed the patient with PAPASH syndrome, a PAPA spectrum disorder complicated by colitis. This patient had PAPASH syndrome with colitis and was MPO-ANCA and anticardiolipin antibodies-positive; it is unclear whether these antibodies play a role in this disease, but it may provide clues to further elucidate its pathogenesis.

Ancient friends, revisited: Systematic review and case report of pyoderma gangrenosum-associated autoinflammatory syndromes

In the last decade, new scientific findings significantly improved our understanding of the molecular pathogenesis of autoinflammation and have resulted in the identification and definition of several pyoderma gangrenosum-associated autoinflammatory syndromes (PGAAIS) as new and distinct clinical entities. These different clinical entities include PAPA (pyogenic arthritis, pyoderma gangrenosum and acne conglobata), PASH (pyoderma gangrenosum, acne and suppurative hidradenitis), PAPASH (pyoderma gangrenosum, acne, suppurative hidradenitis and pyogenic arthritis), PsAPASH (pyoderma gangrenosum, acne, suppurative hidradenitis and psoriatic arthritis), PASS (pyoderma gangrenosum, acne conglobata, suppurative hidradenitis, and axial spondyloarthritis) and PAC (pyoderma gangrenosum, acne and ulcerative colitis), which can be distinguished by their clinical presentation and the presence or absence of mutations in several genes, such as the genes encoding proline-serine-threonine phosphatase-interacting protein 1 (PSTPIP1), nicastrin (NCSTN), Mediterranean fever (MEFV) and nucleotide-binding oligomerization domain-containing protein (NOD). In this systematic review, we summarize the present knowledge of this rapidly developing hot topic and provide a guide to enable the easy diagnosis of these syndromes in everyday clinical practice. Moreover, we report a rare case of PASS syndrome demonstrating successful treatment with adalimumab and another case of a previously unreported combination of symptoms, including psoriatic arthritis, pyoderma gangrenosum, suppurative hidradenitis and Crohn’s disease (newly coined PsAPSC), as examples. Because of the identification of similar genetic and pathogenic mechanisms of PGAAIS, we think the wide variety of seemingly different syndromes may represent distinct phenotypes of one disease.

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New scientific findings improved the understanding of the molecular pathogenesis of autoinflammation.

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There is a similar genetic background and clinical findings of PGAAIS.

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Because of the similar genetic and pathogenic mechanisms of PGAAIS may represent distinct phenotypes of one disease.

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We present a 4-sep guide to enable the easy diagnosis of theses disease in clinical practice.

Cutaneous clues to diagnose autoinflammatory diseases

Systemic autoinflammatory diseases (AIDs) are a group of disorders characterized by recurrent episodes of systemic inflammation. Suspecting the diagnosis can be difficult and many of the clinical manifestations are common to different diseases. Although most of the cutaneous manifestations are non-specific, it is important to know them because sometimes they can lead to the diagnosis. The purpose of this review was to synthesize the main cutaneous lesions of autoinflammatory diseases to aid in their diagnosis.

A Unified Concept of Acne in the PAPA Spectrum Disorders

BACKGROUND

Acne is a common condition. Sometimes acne or acne-like features are a part of autoinflammatory diseases such as PAPA spectrum disorders. Our objective wasto determine whether acne in PAPA spectrum disorders has specific phenotypic traits.

SUMMARY

This is aliterature review on reported cases of patients with PAPA, PAMI, PASH, PAPASH, PsAPASH, PAC or PASS syndrome. Acne was classified into four categories: moderate, severe, nodulocystic, acne fulminans.One hundred patients were included. Age of onset of acne and topography were the same as in acne vulgaris. Acne's phenotype was at least severe (including acne fulminans, nodulocystic and severe) in 83% of cases. Genetic mutations or variants with potential pathological significance were reported in 49 patients. The addition of isotretinoin to biotherapies was required to control acne in several patients.

Phenotypes and Pathophysiology of Syndromic Hidradenitis Suppurativa: Different Faces of the Same Disease? A Systematic Review

<b><i>Background:</i></b> There is growing evidence that (certain) hidradenitis suppurativa (HS) comorbidities comprise syndromes including HS as a key cutaneous manifestation. These apparently autoinflammatory syndromes and their diagnostic delay might have detrimental effects on affected patients. <b><i>Methods:</i></b> A systematic review was performed on the databases MEDLINE, EMBASE, and CENTRAL utilizing a standardized extraction form according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. <b><i>Results:</i></b> Sixty-four eligible articles on syndromic HS were retrieved. The identified syndromes included already described ones (pyoderma gangrenosum-acne-suppurative hidradenitis, pyogenic arthritis-pyoderma gangrenosum-acne-suppurative hidradenitis, psoriatic arthritis-pyoderma gangrenosum-acne-suppurative hidradenitis, pyoderma gangrenosum-acne vulgaris-hidradenitis suppurativa-ankylosing spondylitis, synovitis-acne-pustulosis-hyperostosis-osteitis) and further novel symptom constellations. Cutaneous signs, including HS lesions, usually precede signs from other organs. The cutaneous signs of a considerable proportion of patients appear refractory to conventional treatment, and monotherapy with biologics does not suffice to sustain remission. <b><i>Conclusion:</i></b> The results are subsequently discussed with focus on the pathophysiology and treatment of the detected syndromes. The dermatologist’s role in the precise diagnosis and early treatment administration of HS is pivotal. The purpose of the treatment should be the effective prevention or delay of the autoinflammatory march and its irreversible consequences.

A child with recurrent pyogenic arthritis with the PSTPIP1 mutation

Pyogenic arthritis, pyoderma gangrenosum, and acne syndrome is a rare disease, linked to an auto-inflammatory pathway. We report a 7-year-old boy with recurrent suppurative knee arthritis without signs of suppurative skin infection or ulcer; his younger brother had the same symptom. Genetic testing indicated the presence of proline-serine-threonine phosphatase interacting protein 1 gene mutation in both boys. Our patient’s grandfather had a history of recurrent pyoderma, and his father though a genetic carrier had no symptoms. Interestingly, our patient displayed markedly high levels of interleukin-6, while interleukin-1 and other cytokines were not elevated. These lab findings led to the treatment of pyogenic arthritis, pyoderma gangrenosum, and acne syndrome with tocilizumab. Previously reported cases of similar phenotypes of the syndrome have not presented in this fashion, nor have there been reported cases of pyogenic arthritis, pyoderma gangrenosum, and acne syndrome with a positive family history and an elevation in interleukin-6. The mutation site of proline-serine-threonine phosphatase interacting protein 1 in this incomplete pyogenic arthritis, pyoderma gangrenosum, and acne syndrome has not been reported before. It is possible that there are other pathogenic ways to trigger these auto-inflammatory disorders. Tocilizumab, which specifically targets interleukin-6, was effective in this case.

[PAPA syndrome with Crohn's disease and primary sclerosing cholangitis/autoimmune hepatitis overlap syndrome]

BACKGROUND

The PAPA syndrome, an acronym for pyogenic sterile arthritis, pyoderma gangraenosum and acne, is an autosomal dominant hereditary disease which is caused by a mutation in the PSTPIP1 ("proline-serine-threonine phosphatase interacting protein 1") gene located on chromosome 15 and encodes the proline-serine-threonine phosphatase-interacting protein 1. An association with Crohn's disease (CD), autoimmune diseases of the liver and PAPA syndrome has not yet been reported in the literature.

OBJECTIVE

To thoroughly investigate a family with three affected members (mother and 2 children) with newly diagnosed PAPA syndrome and intestinal and hepatobiliary symptoms.

MATERIAL AND METHODS

We performed an in-depth phenotyping, dermatologic, radiologic, rheumatologic, gastroenterologic, histologic and genetic analysis in this family.

RESULTS

All three family members could be newly diagnosed as suffering from PAPA syndrome and carried the known disease-causing mutation c.688G > A (p.Ala230Thr) in the PSTPIP1 gene. The younger son suffered from CD in addition to PAPA syndrome. The mother additionally suffered from ulcerative colitis (UC) and an overlap syndrome between autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC). A mutation in in the NOD2 ("nucleotide binding oligomerization domain containing protein 2") gene could not be detected in any of the three persons affected.

CONCLUSION

We extended the symptoms of PAPA syndrome to CD and autoimmune liver disease. These different disease entities might share a similar pathogenetic mechanism or even represent a new syndrome. This can be clarified in the future by screening patients with PAPA syndrome for intestinal and also hepatobiliary diseases.

Improvement of Ulcerations in Treatment-Resistant Chronic Scarring in a Patient with Pyoderma Gangrenosum After Improving Vascular Insufficiency, Gently Removing Necrotic Debris, and Decreasing Wound Fluid

BACKGROUND Classical pyoderma gangrenosum is a rare, inflammatory, neutrophilic dermatosis that commonly presents with severe ulcerations on the lower extremities and is often misdiagnosed and mistreated. Delay in treatments can lead to worsening of the ulcerations and allows for multiple comorbid factors. Pyoderma gangrenosum is most commonly treated with immunosuppressants or anti-inflammatory agents and is often worsened by surgical procedures due to the presence of pathergy. In acute cases, a course of anti-inflammatory treatments works well in alleviating symptoms and reducing ulcerations and residual scarring. However, in chronic cases with the presence of severe scarring and necrotic ulcerations, the simple implementation of systemic immunosuppressants is frequently ineffective alone. Although not mentioned in most case reports on pyoderma gangrenosum, the chronicity of its inflammatory component can lead to necrosis and scarring and subsequent vascular insufficiency. CASE REPORT We present a severe case of chronic ulcerative pyoderma gangrenosum in a patient who had treatment-resistant ulcerations and cribriform edematous scarring with subsequent vascular insufficiency of the right lower extremity. This patient, while receiving topical clobetasol, had marked improvement in the healing of his ulcerations only after starting a novel course of cadexomer iodine, compression stockings, and pentoxifylline. CONCLUSIONS The efficacy of non-anti-inflammatory treatments indicates that chronic pyoderma gangrenosum with extensive scarring is commonly associated with the comorbid factors of vascular insufficiency, necrotic debris, and extensive wound fluid. In cases of ulcerations in chronic pyoderma gangrenosum that are resistant to anti-inflammatory treatments alone, one should identify and address other compounding factors that may inhibit wound healing.

Pyoderma gangraenosum – from the right diagnostic investigations to targeted therapy

Pyoderma gangrenosum (PG) is a rarely diagnosed neutrophilic skin disorder that still remains a diagnosis of exclusion. Therefore, the diagnosis has to be done in the synopsis of typical clinical findings, patient’s history and exclusion of relevant differential diagnoses. There are numerous references to relevant comorbidities from the metabolic syndrome, rheumatoid arthritis and inflammatory bowel diseases. Of particular importance is the potential association of PG with (haematologic) neoplasms. Treatment of PG includes topical and systemic immuno-modulating or immuno-suppressant therapies. Most important are for topical as well as systemic treatments are glucocorticoids. All other treatments represent an off-label-use. Especially Cyclosporine and TNF-α-inhibitors demonstrated very good and promising clinical results. Accompanying modern moist wound-therapy concepts avoiding painful dressings and an analgesic therapy are recommended.