Pyoderma Gangrenosum (Pathergy Trap): Rapidly Expanding Violaceous Undermined Ulcer and Why Surgical Debridement Catastrophically Worsens Necrosis¶

Pyoderma gangrenosum (PG) is a rare, non-infectious, autoinflammatory neutrophilic dermatosis in which dysregulated innate immune signaling drives massive numbers of mature, sterile polymorphonuclear neutrophils into the dermis, melting collagen and subcutaneous tissue within hours to days. Despite its misleading historical name coined in 1930, pyoderma gangrenosum is neither a bacterial infection ("pyoderma") nor true ischemic vascular gangrene. Instead, it typically begins as a tender inflammatory papule, sterile pustule, or hemorrhagic vesiculopustule, often triggered at the exact site of a minor skin injury, insect bite, venipuncture, or surgical incision, a hallmark phenomenon known as cutaneous pathergy (present in 30 to 50 percent of patients). Within 24 to 72 hours, the sterile pustule breaks down centrally and expands centrifugally at a terrifying speed (1 to 2 centimeters per day) into an excruciatingly painful, purulent, necrotic crater ringed by a pathognomonic boggy, gunmetal-gray to deep violaceous (purple-blue), undermined, overhanging border surrounded by a bright erythematous halo. Between 50 and 70 percent of patients with pyoderma gangrenosum have an underlying systemic disease, most commonly Inflammatory Bowel Disease (Ulcerative Colitis or Crohn Disease), Rheumatoid Arthritis or Seronegative Spondyloarthritis, Monoclonal Gammopathy (specifically IgA paraproteinemia), or Hematologic Malignancy (Acute Myeloid Leukemia or Myelodysplastic Syndrome). Because a rapidly expanding, purulent ulcer accompanied by fever, severe pain, and a white blood cell count of 20,000 to 40,000 cells/mcL closely mimics necrotizing fasciitis (flesh-eating bacterial infection) or a postoperative wound abscess, surgeons who do not recognize pyoderma gangrenosum frequently rush the patient to the operating room for wide radical surgical debridement. In pyoderma gangrenosum, every stroke of the surgeon's scalpel triggers an explosive pathergic neutrophil storm along the freshly cut skin margin, causing the ulcer to double or triple in size overnight, exposing tendons and bone, or leading to unnecessary limb amputation. If a patient develops a rapidly expanding ulcer with a purple undermined border after minor trauma or surgery, call your local номера за спешни случаи or seek urgent hospital dermatology evaluation immediately. Also review our sibling guides on calciphylaxis, violaceous retiform plaques, and sodium thiosulfate, еризипел срещу некротизиращ фасциит срещу стазисен дерматит, и black widow latrodectism vs brown recluse loxoscelism necrotic ulcer triage.

Your immediate emergency priorities are to place an immediate "DO NOT SURGICALLY DEBRIDE" warning on the patient's chart and wound dressing, differentiate pyoderma gangrenosum from true necrotizing soft-tissue infection using bedside clinical examination, Gram stain, tissue cultures, and the validated PARACELSUS or Delphi Diagnostic Criteria, perform a cautious elliptical or punch skin biopsy of the active violaceous border (only if needed to exclude infection, vasculitis, or malignancy, and ideally while initiating systemic immunosuppression to blunt biopsy pathergy), and start rapid-acting systemic anti-neutrophil immunosuppression, specifically high-dose systemic Corticosteroids (oral Prednisone 1 to 2 mg/kg/day or pulse IV Methylprednisolone 500 to 1,000 mg/day for 3 days), oral Cyclosporine (4 to 5 mg/kg/day), or intravenous Infliximab (5 mg/kg, the gold standard for Crohn/Ulcerative Colitis-associated and peristomal PG).

Направете това сега¶

1. Seek Urgent Hospital Emergency and Dermatology Evaluation if a skin pustule, surgical incision, or minor bruise rapidly ulcerates into an excruciatingly painful crater with a purple-blue, boggy, overhanging border. Dial 911 in the United States and Canada, 999 in the United Kingdom, 112 across the European Union, 000 in Australia, or consult our global directory of номера за спешни случаи.
2. STOP Any Planned Sharp Surgical Debridement or Wide Excision Immediately (The Pathergy Trap): If a patient has known or strongly suspected pyoderma gangrenosum (including Postoperative Pyoderma Gangrenosum [PPG] appearing 4 to 14 days after breast reduction/reconstruction, cesarean section, cardiothoracic surgery, or abdominal stoma creation), sharp surgical debridement with a scalpel or curette is strictly contraindicated. Surgical cutting recruits massive waves of IL-1beta-, IL-8-, and TNF-alpha-driven neutrophils to the newly incised dermis, causing catastrophic centrifugal ulceration across the entire chest, abdomen, or limb within 24 hours.
3. Rule Out True Necrotizing Fasciitis, Ecthyma Gangrenosum, and Deep Fungal Infection Without Triggering Unnecessary Radical Excision:
4. Why Surgeons Get Tricked: Pyoderma gangrenosum causes a creamy yellow-white sterile purulent exudate (composed of millions of dead neutrophils), high fever, and leukocytosis up to 35,000/mcL.
5. How to Tell Them Apart at the Bedside: Unlike necrotizing fasciitis (which spreads deep along the subcutaneous muscle fascia ahead of visible skin breakdown, produces subcutaneous gas/crepitus, foul "dishwater" fluid, and systemic septic shock with hypotension and lactic acidosis), pyoderma gangrenosum is a primary dermal ulceration with a sharply demarcated, boggy, gunmetal-violaceous undermined overhang, zero subcutaneous gas, zero foul anaerobic odor, palpable peripheral pulses, and negative Gram stains and blood cultures.
6. Postoperative PG Clue: Postoperative bacterial necrotizing wound infections typically strike within 24 to 72 hours of surgery (Group A Streptococcus or Clostridium) or present as a fluctuant stitch abscess, whereas Postoperative Pyoderma Gangrenosum (PPG) classically erupts 4 to 14 days post-op as multiple small sterile pustules along the suture line that coalesce and dehisce the entire incision while sparing the pale nippled areola in breast surgery and failing to improve on broad-spectrum IV antibiotics.
7. Apply Validated Diagnostic Frameworks (The Delphi International Consensus Criteria and the PARACELSUS Score) and Obtain a Targeted Border Biopsy:
8. Under the 2018 Delphi International Consensus, diagnosis requires 1 Major Criterion (biopsy of the ulcer edge demonstrating a dense sterile neutrophilic dermal infiltrate) plus at least 4 of 8 Minor Criteria (exclusion of infection on histology/culture; pathergy; history of IBD or inflammatory arthritis; papule/pustule ulcerating within 4 days; peripheral erythema, undermining border, and tenderness; multiple ulcerations with at least one on the anterior lower leg; cribriform or "crushed tissue paper" wrinkled scars at healed sites; and decrease in ulcer size within 1 month of starting immunosuppressive medication).
9. Under the PARACELSUS Score (where a score of >= 10 points indicates a > 90% probability of PG), major points are awarded for Progressing disease (3 pts), Assessment of relevant differential diagnoses (3 pts), and Reddish-violaceous wound border (3 pts), plus Amelioration by immunosuppressants (2 pts), Characteristic bizarre ulcer shape (2 pts), Extreme pain > 4/10 on VAS (2 pts), and Localized pathergy phenomenon (2 pts).
10. Start High-Dose Systemic Corticosteroids or Cyclosporine Immediately to Halt the Neutrophil Storm:
11. First-Line Systemic Rescue (STOP GAP Trial Evidence): Administer Oral Prednisolone/Prednisone at 0.75 to 1.5 mg/kg/day (up to 60 to 100 mg/day), or for fulminant, rapidly expanding multilocular or postoperative PG, administer Pulse Intravenous Methylprednisolone (500 to 1,000 mg IV once daily for 3 to 5 consecutive days), which typically arrests centrifugal border expansion and reduces agonizing pain within 48 to 72 hours.
12. Alternative First-Line Rescue (Oral Cyclosporine): The landmark UK STOP GAP randomized controlled trial proved that Oral Cyclosporine at 4 to 5 mg/kg/day (divided twice daily) has identical ulcer healing efficacy and speed to oral prednisolone, making Cyclosporine the preferred first-line agent in patients with brittle diabetes, severe osteoporosis, obesity, or steroid psychosis (avoid Cyclosporine in renal insufficiency or uncontrolled hypertension).
13. Initiate Biologic TNF-Alpha Blockade (IV Infliximab 5 mg/kg) for Inflammatory Bowel Disease-Associated, Peristomal, or Steroid-Refractory Pyoderma Gangrenosum: Intravenous Infliximab (5 mg/kg at Weeks 0, 2, and 6, then every 8 weeks) is the only biologic therapy supported by a randomized placebo-controlled trial for pyoderma gangrenosum, achieving rapid clinical response in 69 percent of patients within 2 weeks and serving as the undisputed treatment of choice when PG coexists with active Crohn disease, Ulcerative Colitis, or peristomal ulceration.
14. Practice Strictly Atraumatic, Moisture-Balanced Local Wound Care and Gentle Compression: Never apply dry gauze that sticks to the ulcer bed and rips viable dermis upon removal (triggering pathergy). Protect the surrounding intact skin with a zinc oxide or cyanoacrylate barrier film, apply super-potent topical clobetasol propionate 0.05% ointment or topical tacrolimus 0.1% ointment directly onto the inflamed violaceous overhanging border, dress the central crater with non-adherent silicone mesh, hydrogel, or hydrofiber/alginate dressings, and apply gentle multi-layer compression bandaging once acute border pain is controlled by systemic steroids.

Decision tree: suspected Pyoderma Gangrenosum vs Necrotizing Fasciitis vs Venous/Arterial Ulcer vs Martorell Ulcer¶

flowchart TD
    A["Patient Presents with Rapidly Expanding, Excruciatingly Painful Cutaneous Ulcer (1 to 2 cm/day) + Purulent Yellow Base + Boggy Violaceous/Gunmetal-Gray Undermined Overhanging Border (Often After Minor Trauma, Venipuncture, or Recent Surgery)"] --> B{"Step 1: Immediate Rule-Out of True Necrotizing Soft-Tissue Infection (Necrotizing Fasciitis): Is There Subcutaneous Gas/Crepitus, Foul Anaerobic Odor, Fascial Tracking Beyond Skin Margins, or Septic Shock?"}
    B -->|YES: True Bacterial Necrotizing Fasciitis / Wet Gangrene| C["Emergency Operating Room Surgical Exploration & Debridement + IV Vancomycin + Piperacillin-Tazobactam/Meropenem + Clindamycin"]
    B -->|NO: Primary Dermal Ulceration with Violaceous Undermined Overhang + Negative Gram Stain + Palpable Pulses| D["Step 2: Apply PARACELSUS Score (>= 10 Points) & Screen for Systemic Associations: IBD (Ulcerative Colitis / Crohn), Rheumatoid Arthritis, IgA Gammopathy / AML / MDS, or Levamisole-Adulterated Cocaine Use"]
    D --> E["MANDATORY SAFETY ORDER: Place 'STRICT PATHERGY PRECAUTIONS - NO SHARP SURGICAL DEBRIDEMENT, NO DRY ADHERENT GAUZE' Sign at Bedside"]
    E --> F{"Step 3: Perform Targeted Edge Biopsy (Include Violaceous Border + Subcutaneous Fat) for H&E Histopathology + Bacterial, Fungal & Mycobacterial Tissue Cultures"}
    F --> G{"Assess Disease Severity, Extent & Underlying Systemic Comorbidities"}
    G -->|Severe, Rapidly Expanding, Multilocular, or Postoperative PG| H["FIRST-LINE SYSTEMIC RESCUE: 1. Oral Prednisone (1 to 1.5 mg/kg/day) OR Pulse IV Methylprednisolone (500 to 1,000 mg/day x 3-5 days); OR 2. Oral Cyclosporine (4 to 5 mg/kg/day - STOP GAP Trial Equivalent)"]
    G -->|Coexisting Inflammatory Bowel Disease (Crohn / UC), Peristomal PG, or Steroid-Refractory Disease| I["BIOLOGIC RESCUE: Intravenous Infliximab (5 mg/kg at Weeks 0, 2, 6) or Adalimumab + Systemic Corticosteroid Bridge"]
    G -->|Underlying Hematologic Malignancy (AML / MDS / IgA Myeloma) or Severe Sepsis Contraindicating Steroids| J["High-Dose Intravenous Immunoglobulin (IVIG 2 g/kg over 2-5 days) or Targeted IL-1 Antagonist (Anakinra / Canakinumab) + Treat Underlying Leukemia/Myeloma"]
    G -->|Small (< 3 cm), Early, Localized, or Mild Peristomal Ulcer| K["Super-Potent Topical Clobetasol 0.05% Ointment or Topical Tacrolimus 0.1% Applied to Violaceous Border + Cautious Intralesional Triamcinolone (40 mg/mL) + Non-Adherent Silicone Dressings"]

Pathophysiology: the sterile neutrophil storm, cutaneous pathergy, and the five clinical variants of Pyoderma Gangrenosum¶

Pyoderma gangrenosum sits at the severe ulcerative end of the neutrophilic dermatoses spectrum (alongside Sweet syndrome, subcorneal pustular dermatosis, hidradenitis suppurativa, and erythema elevatum diutinum).

HOW MINOR TRAUMA TRIGGERS EXPLOSIVE PATHERGIC ULCERATION IN PG
=======================================================================
[Minor Cutaneous Trauma: Needle Stick, Bug Bite, Scalpel Incision]
                               |
                               v
[Keratinocyte Damage Releases DAMPs (Damage-Associated Molecular
 Patterns: ATP, HMGB1, S100 Proteins, LL-37 Cathelicidin)]
                               |
                               v
[Hyper-Reactive NLRP3 Inflammasome Activation in Dermal Macrophages]
   * Massive local surge of Interleukin-1 beta (IL-1beta), IL-1alpha,
     Tumor Necrosis Factor-alpha (TNF-alpha), IL-8 (CXCL8), IL-17,
     and Granulocyte Colony-Stimulating Factor (G-CSF).
                               |
                               v
[STERILE NEUTROPHIL AVALANCHE INTO THE DERMIS]
   * Millions of mature neutrophils flood the dermis and release
     Matrix Metalloproteinases (MMP-9, MMP-2), Neutrophil Elastase,
     Myeloperoxidase, and Neutrophil Extracellular Traps (NETs).
                               |
                               v
[LIQUEFACTIVE DERMAL COLLAGEN MELTDOWN ("Undermining")]
   * Because neutrophils dissolve the deep reticular dermis faster
     than the overlying epidermis dies, the dermal floor caves in
     beneath the skin edge -> Creates the classic BOGGY, VIOLACEOUS,
     OVERHANGING ("UNDERMINED") BORDER + Cribriform "Tissue Paper" Scar.
=======================================================================

The Five Distinct Clinical Variants of Pyoderma Gangrenosum¶

1. Classic Ulcerative Pyoderma Gangrenosum (85% of Cases): Most frequently erupts on the anterior pretibial lower legs (70%), trunk, or abdomen. Begins as a tender deep red nodule or sterile pustule surrounded by an erythematous halo that rapidly necroses centrally into a deep ulcer with a purulent-appearing sterile base and a boggy, bluish-purple (violaceous), undermined overhanging border. When it heals under immunosuppression, re-epithelialization grows out from spared hair follicles in bridges, leaving a pathognomonic cribriform ("sieve-like" or "crushed cigarette/tissue paper") atrophic scar.
2. Булозна (атипична) гангренозна пиодермия (червен флаг за хематологично злокачествено заболяване): Проявява се с остри, болезнени, повърхностни концентрични хеморагични були (пълни с кръв мехури) със синьо-сив възпалителен ореол, предимно по лицето, дорзалните ръце и горните крайници, а не по краката. Критичен онкологичен бисер: Над 70 процента от пациентите с Булозна пиодермия гангренозум имат подлежащо хематологично злокачествено заболяване, по-специално Остра миелоидна левкемия (AML), Миелодиспластичен синдром (MDS), Миелопролиферативни неоплазми или IgA мултиплен миелом, и често се припокрива клинично и хистологично с булозен синдром на Sweet.
3. Pustular Pyoderma Gangrenosum (Acute IBD Flare Marker): Presents as crops of painful, discrete 2 to 5 millimeter sterile pustules surrounded by an erythematous halo on the extensor limbs and upper trunk that do not all progress to deep craters; occurs almost exclusively during acute, severe flares of Ulcerative Colitis or Crohn Disease and resolves when the bowel flare is treated with corticosteroids or infliximab.
4. Vegetative (Superficial Granulomatous) Pyoderma Gangrenosum: A slower, less painful, verrucous (wart-like), superficial ulcerative plaque with sinus tracts that lacks the aggressive violaceous undermined border, typically occurring on the trunk in patients without underlying systemic disease and responding well to topical steroids, dapsone, or minocycline.
5. Peristomal Pyoderma Gangrenosum (PPG): Occurs immediately adjacent to an abdominal ileostomy or colostomy stoma in patients with Inflammatory Bowel Disease (accounting for 15% of all PG cases), triggered by chronic mechanical pathergy from Tight Stoma Appliance Wafers, adhesive stripping, or leaking digestive enzymes. Because the painful deep ulcer prevents the ostomy bag wafer from sealing against the skin, stool leaks continuously onto the raw crater, creating a vicious cycle of pain and appliance failure.

Autoinflammatory Genetic Syndromes Featuring Pyoderma Gangrenosum (PAPA, PASH, and PAPASH)¶

In younger patients presenting with severe, recurrent pyoderma gangrenosum accompanied by destructive acne or hidradenitis suppurativa, clinicians screen for monogenic autoinflammatory inflammasomopathies driven by mutations in the PSTPIP1 (Proline-Serine-Threonine Phosphatase Interacting Protein 1) or NCSTN genes that hyperactivate IL-1beta: - PAPA Syndrome: Pyogenic sterile Arthritis + Pyoderma gangrenosum + severe cystic Acne. - PASH Syndrome: Pyoderma gangrenosum + Acne + Suppurative Hidradenitis (hidradenitis suppurativa). - PAPASH / PASS Syndromes: Adding Psoriatic arthritis or Ankylosing Spondylitis to the triad. These syndromes respond dramatically to targeted IL-1 blockade (Anakinra or Canakinumab) or TNF-alpha inhibitors (Infliximab / Adalimumab).

Side-by-side differential diagnosis: Pyoderma Gangrenosum vs Necrotizing Fasciitis vs Martorell Hypertensive Ischemic Ulcer vs Brown Recluse Spider Bite vs Levamisole Vasculopathy¶

The PARACELSUS Diagnostic Score and Mandatory Laboratory Workup for Suspected Pyoderma Gangrenosum¶

1. Как да изчислим оценката на PARACELSUS до леглото¶

Публикувано от Jockenhovel и колеги като диагностичен инструмент с висока чувствителност за разграничаване на пиодерма гангренозум от венозна, артериална и инфекциозна имитация, общ резултат от 10 точки или по-висок потвърждава висока вероятност за пиодерма гангренозум: - Major Criteria (3 Points Each): 1. Progressing disease (rapidly expanding ulceration developing in < 6 weeks). 2. Assessment and exclusion of relevant differential diagnoses (venous/arterial insufficiency, infection, vasculitis, calciphylaxis). 3. Reddish-violaceous (purple-blue) wound border. - Minor Criteria (2 Points Each): 4. Amelioration (rapid improvement) by immunosuppressant drugs. 5. Characteristic bizarre, polycyclic, or serpiginous ulcer shape with undermined edges. 6. Extreme pain (> 4 out of 10 on the Visual Analog Scale, often 8 to 10 out of 10). 7. Localized pathergy phenomenon (ulcer triggered at site of trauma, surgery, or biopsy). - Additional Criteria (1 Point Each): 8. Suppurative inflammation on histopathology (dense dermal neutrophilic infiltrate). 9. Uподкопани ръбове на раната. 10. Systemic disease associated (IBD, rheumatoid arthritis, IgA gammopathy, hematologic malignancy).

2. Mandatory Systemic Workup in Every Newly Diagnosed Patient with Pyoderma Gangrenosum¶

Because 50 to 70 percent of patients harbor an underlying systemic disease (and because PG can be the very first clinical sign of occult Acute Myeloid Leukemia, Myelodysplastic Syndrome, IgA Multiple Myeloma, Crohn Disease, or GPA/ANCA Vasculitis), order this complete diagnostic panel upon admission: - Hematologic and Paraproteinemia Screen: Complete Blood Count (CBC) with manual peripheral blood smear (looking for myeloblasts, dysplastic neutrophils, or Auer rods), Serum Protein Electrophoresis (SPEP) with Immunofixation Electrophoresis (IFE), and Serum Free Light Chains (specifically looking for an IgA monoclonal gammopathy, the classic paraprotein associated with PG). - Gastrointestinal / Inflammatory Bowel Disease Screen: Detailed history of diarrhea, hematochezia, weight loss, or oral aphthae; Fecal Calprotectin and Ileo-colonoscopy with mucosal biopsies if any GI symptoms or unexplained iron-deficiency anemia exist. - Vasculitis, Thrombophilia, and Drug-Induced PG Screen: c-ANCA / PR3 and p-ANCA / MPO (to rule out Granulomatosis with Polyangiitis [GPA] and Levamisole-adulterated cocaine vasculopathy, which causes retiform purpura of the earlobes and PG-like leg ulcers with dual-positive MPO/HNE ANCA), Antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, beta-2 glycoprotein I), Rheumatoid Factor / Anti-CCP, Hepatitis B, Hepatitis C, and HIV serologies, and Urine Toxicology for Cocaine/Levamisole. - Deep Edge Skin Biopsy Protocol (Two Specimens): Obtain a narrow elliptical incisional biopsy or 4-to-6 mm punch biopsy spanning the active erythematous-violaceous border down into subcutaneous fat: send Specimen 1 in formalin for H&E, PAS, Grocott methenamine silver (GMS), and Fite/Ziehl-Neelsen stains, and send Specimen 2 in sterile saline for aerobic, anaerobic, fungal (Blastomyces, Cryptococcus, Histoplasma, Sporothrix), and atypical mycobacterial (M. marinum, M. ulcerans, M. fortuitum) tissue cultures.

Step-by-step Hospital Treatment Protocol: Systemic Immunosuppression, Biologics, and Peristomal Care¶

1. First-Line Systemic Immunosuppression (Prednisone vs. Cyclosporine)¶

• Systemic Corticosteroids: Start Oral Prednisone or Prednisolone at 1.0 to 1.5 mg/kg/day (60 to 100 mg once daily), or for explosive postoperative or multi-ulcer disease, administer Pulse IV Methylprednisolone (500 to 1,000 mg IV daily for 3 to 5 days). Once border progression stops and the undermined overhang flattens (within 1 to 3 weeks), taper slowly over 3 to 6 months.
• Oral Cyclosporine (Calcineurin Inhibitor): Start Oral Modified Cyclosporine (Neoral) at 4 to 5 mg/kg/day divided twice daily. In the landmark STOP GAP randomized controlled trial, oral cyclosporine (4 mg/kg/day) and oral prednisolone (0.75 mg/kg/day) showed identical healing speed at 6 weeks and identical closure rates at 6 months (47%), with prednisolone carrying more serious infections and cyclosporine causing reversible renal dysfunction and hypertension. Monitor blood pressure, creatinine, potassium, and magnesium every 1 to 2 weeks.

2. Targeted Biologic and Steroid-Sparing Therapies¶

• TNF-Alpha Inhibitors (Infliximab and Adalimumab): IV Infliximab (5 mg/kg at Weeks 0, 2, and 6, then every 6 to 8 weeks) is the gold-standard biologic agent for PG, especially with Crohn Disease, Ulcerative Colitis, or Peristomal PG (screen for latent TB and Hepatitis B first). Subcutaneous Adalimumab (160 mg Week 0, 80 mg Week 2, then 40 to 80 mg weekly) is an effective subcutaneous option.
• IVIG, Steroid-Sparing Agents, and Cytokine Blockers: Give IVIG (2 g/kg over 3 to 5 days) when active malignancy or sepsis contraindicates steroids. Combine steroids or biologics with Oral Dapsone (50 to 200 mg/day after G6PD screening), Mycophenolate Mofetil, Azathioprine, or Colchicine. For refractory cases or PAPA/PASH syndromes, IL-1 antagonists (Anakinra, Canakinumab), IL-23 inhibitors (Ustekinumab), and JAK inhibitors (Upadacitinib) achieve rapid remission.

3. When Is Surgical Skin Grafting EVER Permitted in Pyoderma Gangrenosum?¶

• During Active Inflammation: NEVER. Any surgical incision, sharp debridement, or skin graft harvest (which triggers a brand-new PG ulcer at the thigh donor site) is strictly forbidden.
• During the Quiescent Healing Phase Under Full Immunosuppression: Once steroids, cyclosporine, or infliximab have completely extinguished the neutrophilic border and pain is gone, gentle slough removal, Negative Pressure Wound Therapy (NPWT), or bioengineered dermal substitutes can accelerate closure.

Регионални номера за спешни повиквания и протоколи на агенцията¶

• САЩ и Канада: Наберете 911 за бързо разширяващи се некротични кожни язви, придружени от висока температура, втрисане или непоносима болка. Клиницистите следват Американската академия по дерматология (AAD) и Delphi International Consensus протоколи за диагностика и профилактика на патергия.
• Обединено кралство: Наберете 999 или продължете до отдела за спешна помощ на NHS. Съгласно насоките на Британската асоциация на дерматолозите (BAD) и Мрежата за дерматологични клинични изпитвания на Обединеното кралство (UK DCTN STOP GAP Trial), болничните дерматологични екипи започват перорален преднизолон (\(0,75\text{ mg/kg/ден}\)) или циклоспорин (\(4\text{ mg/kg/ден}\)), като същевременно налагат строг хирургичен дебридман забрани.
• Европейски съюз: Наберете 112 във всички държави-членки на ЕС. Следвайте указанията на Европейската академия по дерматология и венерология (EADV) и Немското дерматологично дружество (DDG) PARACELSUS Score.
• Австралия, Нова Зеландия и Азиатско-Тихоокеанския регион: Наберете 000 в Австралия, 111 в Нова Зеландия (Australasian College of Dermatologists [ACD]), 119 в Япония и Южна Корея (Насоки на Японската дерматологична асоциация [JDA] Pyoderma Gangrenosum, където Adalimumab има официално регулаторно одобрение), 995 в Сингапур или 112 / 108 в Индия.

Често задавани въпроси¶

Защо хирургичният дебридман влошава катастрофално язвата на Pyoderma Gangrenosum?¶

За разлика от некротизиращия фасциит (който се причинява от месоядни бактерии, които трябва да бъдат отрязани в операционната зала), Pyoderma Gangrenosum (PG) е стерилно автоимунно и автовъзпалително състояние, при което собствените бели кръвни клетки (неутрофили) на пациента погрешно атакуват кожата, когато тя е наранена. Тази преувеличена реакция към травма се нарича кожна патергия. Когато хирург обърка гнойна PG язва с бактериална инфекция и отреже лилавата кожна граница със скалпел, увредените кожни клетки освобождават алармени сигнали (интерлевкин-1 бета и TNF-алфа), които призовават милиони свежи неутрофили към току-що изрязания ръб. В рамките на 24 до 48 часа тези неутрофили усвояват здравия колаген по протежение на хирургичния ръб, причинявайки удвояване или утрояване на размера на язвата.

Как лекарите могат да разграничат Postoperative Pyoderma Gangrenosum от бактериална хирургична инфекция на рана след операция на гърдата или корема?¶

Четири клинични улики разграничават следоперативната гангренозна пиодермия (PPG) от бактериалната инфекция на раната: (1) Време: PPG почти винаги започва 4 до 14 дни след операцията като малки стерилни пустули по протежение на линията на разреза, които внезапно се сливат и разкъсват раната, докато вирулентните стрептококови некротизиращи инфекции от група А поразяват в рамките на 24 до 72 часа; (2) Външен вид на границата: PPG създава блатен, бронзово лилав, надвиснал („подкопан“) ръб на кожата; (3) Съхраняване на зърната при операция на гърдата: при намаляване или реконструкция на гърдата PPG, кожата на гърдата се стопява, докато зърно-ареоларният комплекс е уникално пощаден; и (4) Антибиотичен неуспех: PPG се влошава въпреки широкоспектърните интравенозни антибиотици и хирургични дебридмани, но спира да се разширява в рамките на 48 часа след започване на високи дози кортикостероиди.

Защо Pyoderma Gangrenosum се нарича "Pyoderma", ако няма бактериална инфекция?¶

Когато дерматолозите Brunsting, Goeckerman и O'Leary за първи път назовават състоянието през 1930 г., те погрешно смятат, че е причинено от стрептококова или стафилококова инфекция ("пиодерма" означава гной в кожата), която води до смърт на тъканите ("gangrenosum"). Съвременната медицина по-късно доказа, че гъстата жълта гной, покриваща основата на прясна PG язва, не съдържа никакви бактерии; това всъщност е стерилна супа, направена от милиони хиперактивни бели кръвни клетки (неутрофили), които са наводнили дермата поради свръхактивна вродена имунна система. Въпреки че името е историческо погрешно наименование, то остава в медицинските учебници почти век.

Какви основни заболявания най-често се свързват с Pyoderma Gangrenosum?¶

Между 50 и 70 процента от пациентите, диагностицирани с Pyoderma Gangrenosum, имат подлежащо системно заболяване. Четирите най-чести асоциации са: (1) Възпалително заболяване на червата (улцерозен колит и болест на Crohn, наблюдавани в 20% до 30% от случаите); (2) Възпалителен артрит (ревматоиден артрит и анкилозиращ спондилит); (3) Хематологични ракови заболявания и кръвни заболявания (по-специално остра миелоидна левкемия [AML], миелодиспластичен синдром [MDS] и IgA моноклонална гамапатия, които са особено свързани с булозния вариант на PG на ръцете и лицето); и (4) Генетични автовъзпалителни синдроми като PAPA и PASH синдром.

Кое работи по-добре при Pyoderma Gangrenosum: преднизон или циклоспорин?¶

Според забележителното рандомизирано контролирано проучване STOP GAP в Обединеното кралство, оралният преднизолон (0,75 mg/kg/ден) и пероралният циклоспорин (4 mg/kg/ден) са еднакво ефективни: и двата спират прогресията на язвата с еднаква скорост и постигат почти идентични нива на пълно излекуване (почти 50% излекувани до 6 месеца). Лекарите избират между тях въз основа на други здравословни състояния на пациента: преднизон (или IV метилпреднизолон) се предпочита при пациенти с бъбречно заболяване или високо кръвно налягане, докато циклоспоринът се предпочита при пациенти с диабет, затлъстяване, остеопороза или анамнеза за индуцирани от стероиди психиатрични странични ефекти. Когато PG е свързан с болестта на Crohn или улцерозен колит, интравенозният инфликсимаб (5 mg/kg) е биологичното лечение със златен стандарт.

Източници и официални указания¶

• Международен консенсус на JAMA Dermatology Delphi (Maverakis E, Ma C, Shinkai K, et al., 2018): Диагностични критерии за Ulcerative Pyoderma Gangrenosum: Делфийски консенсус на международни експерти.
• BMJ (STOP GAP Randomized Controlled Trial, Ormerod AD, Thomas KS, Craig FE, et al., UK Dermatology Clinical Trials Network): Сравнение на двете най-често използвани лечения за Pyoderma Gangrenosum: Резултати от STOP GAP рандомизирано контролирано проучване (преднизолон срещу циклоспорин).
• JAMA Dermatology (Jockenhovel F, et al.): Резултатът PARACELSUS: Нов диагностичен инструмент за Pyoderma Gangrenosum.
• Британската асоциация на дерматолозите (BAD) и Американската академия по дерматология (AAD): Клинични насоки за неутрофилни дерматози, постоперативно разпознаване на гангренозна пиодермия и превенция на патергия.
• Gut (Brooklyn TN, Dunnill MG, Shetty A, et al.): Инфликсимаб за лечение на Pyoderma Gangrenosum: Рандомизирано, двойно-сляпо, плацебо-контролирано проучване.

Свързани ръководства¶

• Калцифилаксия (калцио-уремична артериолопатия): виолетови плаки, черни струпи и натриев тиосулфат
• Еризипел срещу некротизиращ фасциит срещу стазисен дерматит: непропорционална болка, були и сортиране по LRINEC резултат
• черна вдовица латродектизъм мускулна ригидност срещу кафяв отшелник локсосцелизъм некротична язва сортиране
• Некротизиращ фасциит (инфекция, разяждаща плътта) и целулит са тревожни сигнали
• Номера за спешни повиквания по държави