Interrupting an IFN-γ-dependent feedback loop in the syndrome of pyogenic arthritis with pyoderma gangrenosum and acne.

OBJECTIVES: To study the molecular pathogenesis of PAPA (pyogenic arthritis, pyoderma gangrenosum and acne) syndrome, a debilitating hereditary autoinflammatory disease caused by dominant mutation in PSTPIP1. METHODS: Gene knock-out and knock-in mice were generated to develop an animal model. THP1 and retrovirally transduced U937 human myeloid leukaemia cell lines, peripheral blood mononuclear cells, small interfering RNA (siRNA) knock-down, site-directed mutagenesis, cytokine immunoassays, coimmunoprecipitation and immunoblotting were used to study inflammasome activation. Cytokine levels in the skin were evaluated by immunohistochemistry. Responsiveness to Janus kinase (JAK) inhibitors was evaluated ex vivo with peripheral blood mononuclear cells and in vivo in five treatment-refractory PAPA patients. RESULTS: The knock-in mouse model of PAPA did not recapitulate the human disease. In a human myeloid cell line model, PAPA-associated PSTPIP1 mutations activated the pyrin inflammasome, but not the NLRP3, NLRC4 or AIM2 inflammasomes. Pyrin inflammasome activation was independent of the canonical pathway of pyrin serine dephosphorylation and was blocked by the p.W232A PSTPIP1 mutation, which disrupts pyrin-PSTPIP1 interaction. IFN-γ priming of monocytes from PAPA patients led to IL-18 release in a pyrin-dependent manner. IFN-γ was abundant in the inflamed dermis of PAPA patients, but not patients with idiopathic pyoderma gangrenosum. Ex vivo JAK inhibitor treatment attenuated IFN-γ-mediated pyrin induction and IL-18 release. In 5/5 PAPA patients, the addition of JAK inhibitor therapy to IL-1 inhibition was associated with clinical improvement. CONCLUSION: PAPA-associated PSTPIP1 mutations trigger a pyrin-IL-18-IFN-γ positive feedback loop that drives PAPA disease activity and is a target for JAK inhibition.

What can inherited immunodeficiencies reveal about pyoderma gangrenosum?

Pyoderma gangrenosum (PG) is a rare ulcerative neutrophilic dermatosis that is occasionally associated with primary immunodeficiency. Though contributions from dysregulation of the innate immune system, neutrophil dysfunction and genetic predisposition have been postulated, the precise pathogenesis of PG has not yet been elucidated. This article reviews reported cases of coexisting PG and primary immunodeficiency in order to gain insight into the complex pathophysiology of PG. Our findings suggest that variations in genes such as RAG1, ITGB2, IRF2BP2 and NFκB1 might play a role in genetically predisposing patients to develop PG. These studies support the feasibility of the role of somatic gene variation in the pathogenesis of PG which warrants further exploration to guide targeted therapeutics.

Pyoderma gangrenosum and impact on quality of life: A narrative review.

Pyoderma gangrenosum (PG) is an autoinflammatory disorder typically characterized by progressive ulcers with dense neutrophilic infiltrates in the absence of infectious causes. The chronic nature of this disease significantly impacts the patients' quality of life (QoL). Yet there is currently a dearth of information in the literature regarding standardised treatment guidelines and the impact of PG on patients' QoL. We conducted a literature search on PubMed using the terms "pyoderma gangrenosum" AND "quality of life." We identified nine relevant articles that provide insight into which domains are affected and what treatment can improve QoL. The most common domains involved are physical, emotional, and psychological. Patients tend to feel depressed/anxious, isolated, and embarrassed secondary to PG manifestations. Comorbidities such as Crohn's disease, monoclonal gammopathy of dermatologic significance, and ulcerative colitis can worsen the impact on these patients' QoL. Pain is also a significant contributor to decreasing patients' QoL. Treatments such as topical steroids, adalimumab, and canakinumab may help improve QoL scores. We believe this information can help clinicians guide the care of patients with PG and highlight the need for more studies and clinical trials focusing on PG treatments' impact on QoL.

Pyoderma Gangrenosum of the Genitalia, Anus, and Perineum: Two Case Reports and a Review of Published Cases.

ABSTRACT: Pyoderma gangrenosum is an inflammatory skin disease that presents with rapidly progressive ulcers with violaceous, undermined borders. Despite most commonly affecting the lower extremities, pyoderma gangrenosum can rarely present in the genital, anal, and perineal regions. We describe 2 cases and report a review of published cases.

A core domain set for pyoderma gangrenosum trial outcomes: an international eDelphi and consensus study from the UPGRADE initiative.

BACKGROUND: Pyoderma gangrenosum (PG) is a rare ulcerative skin condition with no current standardized outcomes or outcome measures. With a rich investigational therapeutic pipeline, standardization of outcomes and improvement of data quality and interpretability will promote the appropriate and consistent evaluation of potential new therapies. Core outcome sets (COS) are agreed, standardized sets of outcomes that represent the minimum that should be measured and reported in all clinical trials of a specific condition. OBJECTIVES: To identify and reach a consensus on which domains (what to be measured) should be included in the Understanding Pyoderma Gangrenosum: Review and Analysis of Disease Effects (UPGRADE) core domain set for clinical trials in PG. METHODS: Collaborative discussions between patients and PG experts, and a systematic review of the literature identified items and prospective domains. A three-round international eDelphi exercise was performed to prioritize the domains and refine the provisional items (consensus: ≥ 70% of participants rating a domain as 'extremely important' and < 15% of participants voting 'not important'), followed by an international meeting to reach consensus on the core domain set (consensus: < 30% disagreement). Item-generation discussions and consensus meetings were hosted via online videoconferences. The eDelphi exercise and consensus voting were performed using Qualtrics survey software. Participants were adults with PG, healthcare professionals, researchers and industry representatives. RESULTS: Collaborative discussions and systematic reviews yielded 115 items, which were distilled into 15 prospective domains. The eDelphi exercise removed the three lowest-priority domains ('laboratory tests', 'treatment costs' and 'disease impact on family') and ranked 'pain', 'quality of life' and 'physical symptoms' as the highest-priority prospective domains. Consensus was reached on the domains of 'pain', 'quality of life' and 'clinical signs'. The domain of 'disease course/disease progression' narrowly failed to reach consensus for inclusion in the core set (32% of participants voted 'no'). Refinement of this domain definition will be required and presented for consideration at future consensus meetings. CONCLUSIONS: The UPGRADE core domain set for clinical trials in PG has been agreed by international multistakeholder consensus. Future work will develop and/or select outcome measurement instruments for these domains to establish a COS.

Mortality and Autopsy Findings in Patients with Pyoderma Gangrenosum: A Multi-Institutional Series.

INTRODUCTION: Pyoderma gangrenosum (PG) is a rare ulcerative skin condition with an increased risk of mortality compared to the general population. The causes of this increased risk are not well understood. Misdiagnosis is common in PG, and many studies are limited by the inclusion of misdiagnosed cases. The goal of this study was to review autopsy findings, identify causes of death, and identify factors that may worsen outcomes among deceased patients confirmed to have PG. METHODS: Data was retrospectively reviewed from the electronic medical records at five academic hospitals. A search was conducted for deceased patients with a diagnosis of PG who had an autopsy performed between 2010 and 2020. We report a descriptive analysis of 11 patients and their clinical characteristics, causes of death, and autopsy findings. RESULTS: The average age of death was 62.9 years. Seven patients had at least one underlying condition known to be associated with PG including inflammatory bowel disease, inflammatory arthritis, or a hematologic disorder. The most common cause of death was infection (n = 6, 54.5%), followed by pulmonary embolism (n = 3, 27.3%), and myelodysplastic syndrome (n = 2, 18.2%). Six patients (54.5%) were taking systemic steroids at the time of death. CONCLUSION: The development of PG may shorten life expectancy among those with underlying conditions associated with PG, and common treatments for PG may contribute to the risk of fatal complications. Awareness of the risk of infection, thrombosis, and malignancy among those with PG is necessary for proper management. Further research is needed to explore the relationship between PG and thromboembolism.

Evaluation of Inclusion and Exclusion Criteria for Pyoderma Gangrenosum in Clinical Research: A Systematic Review.

INTRODUCTION: Pyoderma gangrenosum (PG) is a rare, inflammatory dermatologic disease that, as a diagnosis of exclusion with nonspecific histologic features, is difficult to diagnose. As pharmaceutical interest in potential treatments for PG increases, the need for standardized diagnostic criteria to ensure reproducibility, comparability, and external validity of PG research is required. In this study, we aim to characterize the inclusion and exclusion criteria used in the diagnosis of PG in clinical research studies as well as the eligibility of PG in clinical trials. METHODS: A systematic review was conducted to characterize the PG inclusion and exclusion criteria in research studies. An additional search of the USA and international clinical trials databases was conducted as well to capture eligibility criteria for PG trials. RESULTS: Our study revealed a broad range of inclusion and exclusion criteria used to establish the presence or absence of PG. Based on eight distinct categories used to characterize inclusion criteria for research studies, diagnosis by a dermatologist (n = 25, 31.6%), no inclusion criteria listed (n = 21, 26.6%), and clinical and histopathologic features consistent with PG (n = 20, 25.3%) were most common. For current clinical trials, six categories were used to characterize inclusion criteria, of which clinical and histopathologic features consistent with PG (n = 5, 31.3%), identification based on diagnosis of PG (n = 4, 25.0%), and clinical features consistent with PG (n = 3, 18.8%) were the most common. CONCLUSION: This systematic literature review highlights the range of heterogeneity in diagnostic and eligibility criteria used in PG-directed clinical research and current clinical trials and illustrates the need for the development of consensus guidelines and a rigorous framework to enable high-quality future trials for PG.

Current prescribing for pyoderma gangrenosum in the UK and access to biologic medications: results from a UK Dermatology Clinical Trials Network survey of dermatologists.

Pyoderma gangrenosum (PG) is an ulcerative inflammatory disorder affecting the lower legs in 80% of patients. The use of biologic medications to treat PG is increasing, although there is a limited evidence base to guide treatment choices. In some health systems, such as the UK National Health Service, limitations are placed on biologic prescribing for PG, leading to wide variations in prescribing. A survey of mainly UK clinicians showed that prednisolone remains the first-line treatment for PG (90%, 34/38). Biologics have been used by 66% (25/38) of clinicians as second-line therapy, but 19% (7/38) have had prescribing requests declined. Further research is needed to determine optimal treatment strategies for PG.

Tofacitinib therapy for severe pyoderma gangrenosum in a patient with enteropathic arthritis: a case-based review.

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis that is associated with systemic inflammatory conditions. Currently, there is no universally accepted standard therapy for PG, but immunosuppressive (IS) treatment seems essential. We report a patient here who was successfully treated with tofacitinib despite being PG-refractory to multiple anti-tumor necrosis factor alpha (anti-TNF) therapies and conventional IS. In addition, we performed a comprehensive review of all cases of PG treated with JAK inhibitors. We identified 27 cases treated with JAK inhibitors. Approximately 80% of the patients achieved complete recovery within a median of 12 weeks, even though 17 patients (63%) had received biologics before JAKinib treatment. Notably, this recovery could appear as early as 2 weeks. JAK inhibitors may prove useful in the future, particularly for treating immunosuppressive and steroid-resistant pyoderma gangrenosum, according to recent case reports.

Pediatric pyoderma gangrenosum with pulmonary involvement: A case report.

Pyoderma gangrenosum is a rare disease in childhood. Extra-cutaneous manifestations are uncommon in pyoderma gangrenosum, even more so in children, with only a few cases reported in the literature. We present the case of a pediatric patient with pyoderma gangrenosum and associated pulmonary involvement. In this case, the diagnosis was delayed leading to late initiation of therapy, emphasizing the importance of maintaining a high level of suspicion for this diagnosis.

The Pathophysiology and Treatment of Pyoderma Gangrenosum-Current Options and New Perspectives.

Pyoderma gangrenosum (PG) is an uncommon inflammatory dermatological disorder characterized by painful ulcers that quickly spread peripherally. The pathophysiology of PG is not fully understood; however, it is most commonly considered a disease in the spectrum of neutrophilic dermatoses. The treatment of PG remains challenging due to the lack of generally accepted therapeutic guidelines. Existing therapeutic methods focus on limiting inflammation through the use of immunosuppressive and immunomodulatory therapies. Recently, several reports have indicated the successful use of biologic drugs and small molecules administered for coexisting diseases, resulting in ulcer healing. In this review, we summarize the discoveries regarding the pathophysiology of PG and present treatment options to raise awareness and improve the management of this rare entity.

Development of Postsurgical Pyoderma Gangrenosum with New Keloid after Keloid Resection.

ABSTRACT: Keloids are a dermal fibroproliferative disorder and can arise from trauma, acne, vaccination, and herpes zoster. Pyoderma gangrenosum (PG) is a painful ulcerative skin disorder that is associated with neutrophilic dysfunction. However, the pathophysiologies of keloids and PG are not fully understood. The authors encountered an unusual case of a 24-year-old woman who presented with an anterior chest keloid that bore an ulcer. The keloid was resected along with the ulcer, and histology revealed the ulcer to be a neutrophilic PG ulcer. A year after surgery, another ulcer developed in the scar. The ulcer met the PARACELSUS criteria of a postsurgical PG ulcer. After treatment with systemic prednisone and adalimumab for 250 days, the ulcer re-epithelialized. However, relapsed keloids were then observed at the PG site. Corticosteroid taping may be the safest therapy for patients with a history of PG. Conversely, if there is suspicion that a patient is prone to keloid development, diagnostic biopsies and surgical management of PG ulcers should be avoided or conducted with care.

Wound Debridement in Pyoderma Gangrenosum.

BACKGROUND: Wound debridement improves healing in a variety of acute and chronic ulcers. However, there is concern that debridement may trigger pathergy and worsen pyoderma gangrenosum (PG). OBJECTIVE: To determine whether published evidence supports conservative wound debridement for PG. DATA SOURCES: The authors reviewed the literature published in MEDLINE through January 2023 using the search germs "pyoderma gangrenosum" and "debridement." STUDY SELECTION: Articles reporting sharp surgical debridement or maggot debridement for PG were included in the review. The authors also searched the reference sections of the reviewed articles for additional reports on debridement for PG. DATA EXTRACTION: Clinical data regarding patient status, procedures performed, and patient outcomes were extracted from the selected articles. DATA SYNTHESIS: There are multiple reports of uncontrolled, active-phase PG wounds worsening after aggressive excisional debridement of viable inflamed tissues. In contrast, there is no evidence indicating that conservative debridement of nonviable necrotic tissue worsens PG wounds, regardless of the disease activity. There are multiple reports of successful debridement and surgical grafting for PG in remission. CONCLUSIONS: There is no evidence in favor of or against using conservative debridement of nonviable necrotic tissue for a PG wound. Therefore, it should not be considered contraindicated, even in the active phase of the disease.

Risankizumab as a Therapeutic Approach for Recalcitrant Pyoderma Gangrenosum.

ABSTRACT: Pyoderma gangrenosum (PG) is a neutrophilic dermatosis that is challenging to diagnose and treat. Clinicians frequently use fast-acting corticosteroids, which are subsequently combined with slower-acting immunosuppressants to progressively taper the corticosteroid dosage. Current research is focused on the use of monoclonal antibodies (mAbs) directed against target molecules involved in the pathogenesis of PG. However, available data on their efficacy are based on sporadic case reports and clinical experiences, so the authors aimed to evaluate the efficacy of risankizumab, an anti-interleukin-23 mAb, in the management of two complex PG cases. The authors enrolled two patients with PG who were already treated with immunosuppressive therapies. Their management was based on the off-label use of an mAb directed against the p19 subunit of interleukin-23: risankizumab. Patients received subcutaneous injections of 150 mg at the start of treatment, at week 4, and then every 10 weeks thereafter. Systemic therapy was combined with local management of ulcers, based on the principles of TIME (tissue, infection, moisture balance, and epithelialization) applied to the inflammatory and noninflammatory phases of PG. Clinical resolution was obtained at week 24 for patient 1 and week 16 for patient 2 and was maintained until week 40, without adverse effects or disease recurrence. These clinical cases demonstrate that risankizumab is a valid tool in terms of efficacy and safety for complicated cases of multirefractory PG when provided in parallel with local personalized wound management.

Adjunctive hyperbaric oxygen treatment for challenging pyoderma gangrenosum cases.

INTRODUCTION: Pyoderma gangrenosum (PG) is a rare, difficult-to-treat neutrophilic ulcerative cutaneous condition that severely impacts those affected. Treatment options for PG are limited, and disease remission is not guaranteed. Hyperbaric oxygen treatment is a potential therapeutic option for treating various ulcerative conditions not frequently utilized for PG. CASE REPORT: We present a case of a patient with treatment-resistant PG who achieved remission with adjunctive HBOT, and then later had difficulty achieving remission without HBOT during a future flare. DISCUSSION: HBOT should be more readily considered as a treatment option for those with PG.

Chronic ulcer in a patient with essential thrombocythemia taking hydroxyurea.

Chronic skin ulcers in patients with suspected pyoderma gangrenosum can, on closer inspection and further workup, have a different cause. Recognition of key features on clinical examination such as the presence of atrophie blanche is key to avoid misdiagnosis of pyoderma gangrenosum and its subsequent treatment with high-dose corticosteroids and other immunosuppressive medications.

A confounding clinically aggressive case of necrotizing granulomatous and suppurative dermatitis.

Superficial granulomatous pyoderma gangrenosum is a rare, superficial, vegetating form of pyoderma gangrenosum that tends to occur as a single lesion, most commonly on the trunk. Herein, we report a clinically confounding case of disseminated superficial granulomatous pyoderma gangrenosum in a patient with a 5-year history of painful and chronic ulcerations of the bilateral upper extremities and face in a sun exposed distribution. This was a diagnostically challenging case due to the treatment-refractory nature of our patient's skin lesions and the atypical clinical and histologic presentations encountered. We review our clinical decision process and acknowledge other entities that were considered during the clinical course of this case. Additionally, we discuss the lack of responsiveness to various treatment options with eventual successful clearance of this patient's active skin disease with initiation of adalimumab.

Clinical efficacy of crushed prednisolone and hydrocolloid powder in the primary treatment of peristomal pyoderma gangrenosum and correlation to in vitro drug release data.

We evaluated the primary application of crushed prednisolone combined with hydrocolloid powder for clinically diagnosed peristomal pyoderma gangrenosum (PPG). We present our data on this cohort and follow-up of our previous patients. Of the 23 patients who were commenced on this regime, 18 healed (78%). Twenty-two patients commenced on this regime as the primary treatment for their PPG, and for one, it was a rescue remedy after failed conventional therapy. Four patients with significant medical comorbidities failed to heal and one had their stomal reversal surgery before being fully healed. The proposed treatment regime for PPG is demonstrated to be effective, inexpensive and able to be managed in the patient's usual home environment. In vitro drug release analysis was undertaken, and data are presented to provide further insights into the efficacy of this regime.

The role of split-thickness skin grafting in the treatment of vasculitic and pyoderma gangrenosum ulcers in a multidisciplinary wound centre.

Vasculitic and pyoderma gangrenosum ulcers are traditionally treated with immunosuppressants, and the role of surgery in the treatment of these atypical ulcers remains unclear. This study aimed to investigate the need for surgical intervention as well as the outcome and safety of skin grafting in the treatment of 46 patients with vasculitic ulcers and 34 with pyoderma gangrenosum ulcers using data recorded in the validated Wound Registry. Of the 80 patients with atypical ulcers, 14% (n = 11) were treated surgically; these patients were older (p = 0.039), had lower mobility status (p = 0.002), and more often pulmonary diseases, rheumatoid arthritis, and previous arterial procedures (p = 0.007; p = 0.031; p = 0.031, respectively) than those treated conservatively. Of 181 ulcers, 15% (n = 27) were surgically treated, 78% once and 22% multiple times. During follow-up, 92.3% of both surgically and conservatively treated ulcers with available data healed. Of the surgically treated ulcers, median healing time after first surgical procedure was 96 days, and post-surgical complications were considered mild or unrelated to surgery. Our results suggest that if surgery is indicated, skin grafting is a safe and efficient treatment method provided that multidisciplinary approach is applied.

An Unusual Case Presentation of Non-Pathergy Induced Severe Pyoderma Gangrenosum Localized to the Perianal and Intragluteal Regions.

Pyoderma gangrenosum is a rare neutrophil based disorder presenting as a painful sterile ulcer usually below the knee. The disease is also linked to comorbid conditions including inflammatory bowel disease (IBD) and pathergy. Mainstay treatment begins with high dose steroids, either topical for limited disease or systemic for extensive or rapidly progressing disease. This report presents a patient who had perianal and intragluteal cleft pyoderma gangrenosum, not related to IBD or pathergy, where high dose steroids were contraindicated due to history of steroid induced psychosis.