Pyoderma gangrenosum (PG) is a rare, complex, and severe inflammatory dermatosis categorized under the spectrum of neutrophilic dermatoses (NDs), pathologically characterized by sterile neutrophilic infiltration. It is frequently associated with systemic diseases and typically manifests concurrently with or after their diagnosis. We report a rare PG case of an elderly woman who presented 5 months prior to the onset of hematological malignancy (HM), and this unusual clinical presentation led to a misdiagnosis. The patient was initially suspected of having a lower-extremity skin and soft tissue infection (SSTI). Despite repeated debridement and broad-spectrum antibiotic therapy, her condition deteriorated progressively, eventually necessitating amputation. Negative microbial test results ruled out infection. Subsequently, the development of analogous lesions at the venipuncture sites prompted clinicians to reassess the overall clinical condition. Based on prominent neutrophilic infiltration revealed by skin biopsy pathology and the favorable response to glucocorticoid therapy, the initial lower extremity lesions were retrospectively diagnosed as PG. During the follow-up, the patient was diagnosed with myelodysplastic syndrome and was initiated on corresponding treatment. This unusual case enriches the understanding of the PG-HM association and underscores the importance of clinical vigilance and timely reassessment to optimize prognosis.

Chronic leg ulcers are a significant source of morbidity in elderly patients, particularly those with multiple comorbidities. The most common etiologies are vascular, including chronic venous insufficiency, peripheral arterial disease, and diabetic neuropathy. However, ulcers that are non-healing and refractory to standard treatment may reflect rarer underlying pathologies, warranting comprehensive reassessment. We report the case of an 87-year-old woman presenting with recurrent, painful, bilateral lower-limb ulcers, persisting for 18 months on the right leg and 10 months on the left. Her medical history was notable for chronic kidney disease, heart failure, and a previous myocardial infarction managed with dual coronary artery stenting. The ulcers had been treated in the community with dressings and multiple courses of oral antibiotics, with recurrent hospital admissions for secondary infection. She re-presented to the emergency department with worsening ulceration, rigours, raised inflammatory markers, and clinical features of infection. Initial management included intravenous antibiotics, analgesia, specialist wound care, and tissue viability input. Vascular surgical assessment confirmed adequate arterial supply, and there was no clinical evidence of peripheral neuropathy. Despite optimal conventional management, wound healing remained poor, prompting consideration of alternative diagnoses, including pyoderma gangrenosum, vasculitic ulceration, and cutaneous malignancy. Extensive autoimmune and vasculitis screening was negative. Punch biopsy demonstrated a vasculopathic pattern with increased vascular proliferation, fibrinoid necrosis of small vessels, diffuse neutrophilic infiltrates, and fibrin deposition extending into the deeper dermis. These findings were consistent with coexisting livedoid vasculopathy (LV) and acroangiodermatitis (AAD) secondary to chronic venous stasis, excluding other differentials. This combination is rare, particularly in advanced age. Treatment included topical clobetasol 0.05% cream to peri-wound skin, topical potassium permanganate 0.01% to infected areas, oral dapsone 50 mg twice daily for 3 months, and clopidogrel 75 mg daily, alongside compression therapy and multidisciplinary wound care. Marked clinical improvement was observed within two weeks. This case highlights the diagnostic complexity of chronic leg ulcers, the importance of maintaining a broad differential diagnosis, and the pivotal role of skin biopsy and multidisciplinary collaboration in guiding effective, individualised management.

Acute, chronic, and hard-to-heal wounds pose a growing challenge due to reduced patient quality-of-life, higher cost and increased hospital admissions. Although there is no gold standard for wound care, there is a trend toward simple, outpatient-compatible treatment options. Acellular dermal fish skin derived from Gadus morhua (Atlantic cod) is a promising alternative. This retrospective study evaluated the surgical procedures and outcomes associated with fish-skin graft transplantation for difficult-to-treat wounds. Forty-four patients (33 male and 11 female; mean age: 72.4 years; mean wound area: 84.5 cm[2]) were treated with acellular fish skin graft. Wound healing was assessed by photographic documentation, confocal microscopy and clinical evaluation. Patient satisfaction was assessed using a structured questionnaire. A positive effect on wound healing, defined as a reduction in wound size, was observed in 88.6% of cases, with complete wound closure in 45.45% of cases. Most patients reported that the procedure was neither painful nor time-intensive; 95% stated that they would opt for treatment again. Fish skin grafting has also shown beneficial outcomes in complex cases, such as in wounds secondary to pyoderma gangrenosum and wounds with exposed bone. Fish skin graft transplantation represents a safe, well-tolerated and effective option for managing chronic wounds as well as challenging postoperative wounds, such as those at anatomically challenging sites.

Pyoderma gangrenosum (PG) is a neutrophilic dermatosis traditionally regarded as a sterile inflammatory ulcer; however, positive wound cultures are frequently encountered in clinical practice and may complicate or delay diagnosis and management. Data regarding bacterial superinfection in PG remain limited. The objective of this study was to determine the frequency and spectrum of microbial involvement in PG ulcers compared with venous ulcers. We performed a retrospective cohort study of patients evaluated at the University of Utah between June 2012 and June 2025. Electronic medical records were queried using International Classification of Diseases codes to identify patients with PG or venous ulcers, with diagnosis confirmed by manual chart review. Ulcers were included if at least one bacterial wound swab or tissue culture had been obtained. Isolated organisms were recorded, and associations between ulcer type and organism isolation were analysed using Fisher's exact test. The cohort included 292 patients (143 PG, 149 venous ulcers). Secondary microbial growth occurred in 50.3% of PG ulcers and 50.3% of venous ulcers. Pseudomonas aeruginosa was isolated in 11.9% of PG ulcers and 9.4% of venous ulcers (p = 0.57). Staphylococcus species were the most frequently identified organisms in both groups. No statistically significant difference in overall culture positivity or Pseudomonas isolation was observed between ulcer types. These findings demonstrate that PG ulcers are not uniformly sterile, with approximately half demonstrating microbial superinfection. Infection rates were comparable to those observed in venous ulcers, suggesting that secondary microbial involvement is common across chronic wound types. Positive cultures should not preclude the diagnosis of PG, and recognition of superinfection may support appropriate antimicrobial use while avoiding diagnostic delay.

The extra-intestinal manifestations of inflammatory bowel disease are common, these can be encountered before the diagnosis of the gastrointestinal entity and can follow the course of their activity. Moreover, the use of new drugs including biological and immunosuppressive therapies adds additional associations in these patients. There is an association with pyoderma gangrenosum, erythema nodosum, Sweet syndrome, aphthous ulcers, hidradenitis suppurativa, vasculitis, lupus erythematosus-like syndrome, infections, skin malignancy, psoriasiform dermatitis and eczematous reactions. It is important for the professional to have knowledge about these because of the additional mortality and morbidity in patients with Crohn disease and ulcerative colitis. The objective of this article is to provide relevant information regarding the epidemiology, pathogenesis, diagnosis, therapeutics, and prognosis of the most frequent entities associated with inflammatory bowel disease.

Neonatal inflammatory skin and bowel isease type 1 (NISBD1) is a rare autosomal recessive genodermatosis caused by pathogenic variants in ADAM17, a gene essential for epithelial development and cytokine regulation. Affected individuals typically present during infancy with severe cutaneous inflammation, recurrent infections, fragile hair, and variable gastrointestinal involvement. We report a 4-year-old girl with an unusual constellation of mucocutaneous manifestations associated with a novel homozygous ADAM17 mutation (c.436G>A; p.Gln146Lys), thereby expanding the known phenotypic spectrum of NISBD1. This case highlights atypical NISBD1 features, including pyoderma gangrenosum-like ulcerations, pyostomatitis-like mucosal involvement, annular atrophic scarring, and absence of bowel disease.

Mutations in the gene PSTPIP1 may cause several different autoinflammatory syndromes, but the mechanisms by which distinct PSTPIP1 mutations lead to these differing phenotypes are not fully understood. The two best characterized autoinflammatory conditions resulting from PSTPIP1 mutation are pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome and PSTPIP1-associated myeloid-related proteinemia inflammatory (PAMI) syndrome. Here, we report a novel gain-of-function PSTPIP1 mutation (p.N236K) causing PAMI syndrome in a patient with systemic autoinflammation and severe neutropenia. This mutant form of PSTPIP1 shows increased binding to pyrin and leads to heightened inflammasome formation, relative to WT PSTPIP1. We also identify a transcriptional signature in blood from PAMI patients suggestive of enhanced T cell activation and altered neutrophil survival and/or function. Further research on PSTPIP1-related autoinflammatory conditions is needed to more deeply understand the genetic and immunological drivers of disease and contribute to improving patient outcomes.

Chronic wounds cause a significant burden to affected patients and to society. Effective and objective diagnostic and monitoring methods are needed in wound care, and artificial intelligence offers one promising alternative. In this study, real-world wound images were used to train a convolutional neural network to automatically segment wound area and wound tissues on an image. The study included altogether 362 images of venous, arterial, vasculitis and pyoderma gangrenosum wounds. The model was based on a convolutional neural network architecture U-Net, and fully supervised learning was utilised during the training phase. Wound area reached a Dice Similarity Coefficient (DSC) of 0.927 and Intersection over Union (IoU) of 0.868 using an augmented dataset with pretraining. Fibrinous exudate and granulation performed fairly well with DSC 0.750 and 0.696, and with IoU 0.659 and 0.601, respectively. Necrosis present in only 56 images achieved lower performance with DSC 0.503 and IoU 0.502. In conclusion, this study suggested that it is possible to train a neural network to perform well with images taken for purely clinical purposes. Besides wound area, several wound structures can be identified, but wound structure identification performance is dependent on the number of images featuring the structure.