Makindo Medical Notes

Related Subjects: | Nikolsky's Sign | Koebner Phenomenon | Erythema Multiforme | Pyoderma Gangrenosum | Erythema Nodosum | Dermatitis Herpetiformis | Lichen Planus | Acanthosis Nigricans | Acne Rosacea | Acne Vulgaris | Alopecia | Vitiligo | Urticaria | Basal Cell Carcinoma | Malignant Melanoma | Squamous Cell Carcinoma | Mycosis Fungoides (Sézary Syndrome) | Xeroderma Pigmentosum | Bullous Pemphigoid | Pemphigus Vulgaris | Seborrheic Dermatitis | Pityriasis/Tinea Versicolor Infections | Pityriasis Rosea | Scabies | Dermatomyositis | Toxic Epidermal Necrolysis | Stevens-Johnson Syndrome | Atopic Eczema/Atopic Dermatitis | Psoriasis

Always consider Pyoderma Gangrenosum (PG) when assessing ulcerated skin lesions. PG is a rare, non-infectious, inflammatory skin condition characterized by painful ulcers. It is often associated with systemic diseases like inflammatory bowel disease (IBD), rheumatoid arthritis, and hematologic disorders.

About Pyoderma Gangrenosum

• PG can easily be mistaken for common ulcers; always consider other causes beyond venous leg ulcers.
• Be vigilant for skin cancers and other conditions that may mimic simple venous ulcers.
• If in doubt, refer to dermatology for assessment and consider a biopsy.

Clinical Features

• Pain: Ulcers are often very painful compared to their appearance and can progress rapidly.
• Edge: Lesions have violaceous or bluish undermined borders.
• Base: Necrotic tissue with a purulent, granulomatous appearance.
• Size: Lesions can vary from small ulcers to large, rapidly expanding ones.
• Location: Ulcers may develop around surgical sites or stomas (pathergy phenomenon).
• Preceding Lesions: Often start as papules, pustules, or vesicles before ulcerating.
• Trigger: Minor trauma can precipitate ulcer development.
• Associated Diseases: Rheumatoid arthritis, ulcerative colitis, multiple myeloma, and others.
• Medications: Certain drugs like hydroxyurea or granulocyte-macrophage colony-stimulating factor may be implicated.

Causes and Associations

• Idiopathic: Approximately 20% of cases have no identifiable cause.
• Inflammatory Bowel Disease: Both Crohn's disease and ulcerative colitis are commonly associated.
• Haematologic Disorders: Lymphoma, leukemia, multiple myeloma, and myeloproliferative disorders.
• Autoimmune Diseases: Conditions like rheumatoid arthritis and primary biliary cirrhosis.
• Other Associations: Hepatitis, HIV infection, and monoclonal gammopathies.

Investigations

• Laboratory Tests: Elevated inflammatory markers such as FBC, WCC, ESR, and CRP.
• Skin Biopsy: Shows neutrophilic infiltrates in the dermis and epidermis; helps exclude other diagnoses but is not pathognomonic.
• Exclusion of Infection: Important to rule out infectious causes of ulceration.
• Additional Testing: Screen for underlying conditions like IBD, rheumatoid arthritis, and hematologic disorders.

Management

• Avoid Trauma: Surgical interventions can exacerbate the condition due to pathergy (worsening of lesions with minor trauma).
• Topical Therapy: Potent corticosteroids or calcineurin inhibitors (e.g., tacrolimus) applied to affected areas can reduce inflammation.
• Pain Management: Adequate analgesia is essential due to the severe pain associated with PG.
• Wound Care: Use non-adhesive dressings to promote healing and prevent secondary infection.

Systemic Treatments

• Corticosteroids: Systemic corticosteroids are the first-line therapy for moderate to severe cases.
• Immunosuppressive Agents: Medications like ciclosporin or methotrexate can be used as steroid-sparing agents.
• Biologics: TNF-alpha inhibitors (e.g., infliximab, adalimumab) are effective, especially in refractory cases or when associated with IBD.
• Antibiotics: Not typically required unless there is evidence of secondary bacterial infection.