The Scar That Wouldn’t Heal

Nancy Fuller, M.D.

November 23, 2005

55 year old woman with skin lesion on back Referred to Derm for removal Dx: basal cell carcinoma Wide reexcision done after dx established Wound dehiscence 2 weeks later, treated

with antibiotics with no improvement

Over the next 8 months: progressive and persistent dehiscence

Resuturing Stapling Bx: supperative and granulomatous

dermatitis, dermal scar and chronic FB rx Cultures for fungus, mycobacteria, bacteria

? Foreign body reaction? Split thickness skin graft done; continued

episodes of dehiscence ?allergy to suture material? Labs done: CBC, ESR, CRP,

immunoglobulins, RF, ANA

Patient developed 2 new small lesions-started as pustules, progressed to small ulcers

Started on Prednisone and antibiotics Tacrolimus added Significant improvement!!

Dx: Pyoderma Gangrenosum

Objectives: Consider pyoderma gangrenosum in

differential for ulcerative skin lesions Recognize potential problems in

identification and diagnosis, treatment of PG

No financial disclosures

1930 : “rapidly progressive painful supperative cutaneous ulcers with edematous, boggy, undermined and necrotic borders”-coined “ pyoderma gangrenosum”

Neutrophilic Dermatoses Intense epidermal and/or dermal

inflammatory infiltrates Composed mainly of neutrophils No evidence of vasculitis or infection Pathogenesis: unknown; ?cytokine

disregulation? Altered immune reactivity?

Pyoderma Gangrenosum Sweet's Disease Generalized Pustular Psoriasis Reactive Arthritis (Reiter’s Syndrome)-

Balanitis, keratoderma blennorrhagica

Sweet’s Disease Acute onset of

fever/leukocytosis/erythematous plaques

infiltrated by neutrophils Uncommon Female to male 4:1

Associated with many underlying diseases: Malignancies(25%)-most hematopoetic Bacterial infections-strep, mycobacterium,

yersinia, typhus, salmonella Vaccinations Viral infections-CMV, CAH, HIV Drugs-lithium, furosemide, OCPs, TMP/SMZ Autoimmune and Collagen vascular diseases-RA,

SLE, MCTD, Behcet’s ,Hashimoto’s thyroiditis IBD-Crohns, Ulcerative colitis

Diagnostic Criteria:

MAJOR: abrupt onset of typical lesions Histopathology consistent MINOR: antecedent fever or infection Accompanying fever, arthralgias Leukocytosis Good response to systemic corticosteroids,

not to antibiotics

Pyoderma Gangrenosum Ulcerative chronic inflammatory skin lesions Single or multiple Most common on legs, but can be

anywhere Pathergy Painful

Rapid progression of ulceration Usually preceded by a papule, pustule, or

vesicle Histopathology depends on stage, but always

dense neutrophilic infiltrates No evidence of vasculitis on bx

Associated with underlying systemic diseases 50% of the time

-Inflammatory bowel disease: 5% of ulcerative colitis, 2% Crohn’s

-Inflammatory arthritis

-lymphproliferative disorders

Differential diagnosis Deep mycotic infections Bacterial infections, including mycobacteria, Herpes simplex Vasculitis Insect reactions (eg, brown recluse spider) Warfarin skin necrosis Factitial ulcer gumma

Diagnosis All patients with suspected PG: must rule

out other causes of ulcers prior to tx Skin biopsy Labs: CBC, ESR/CRP, LFTs, renal function

studies, SPEP, CXR, coag profile, ANCA, cryoglobulins

Mistaken Identity? Antiphospholipid syndrome Wegeners granulomatosis Chronic venous stasis ulcers Vasculitis Infection Cancer (cutaneous lymphoma, etc)

Treatment No well controlled studies

For mild disease: local treatment such as topical steroids, topical tacrolimus ointment, colloidal membrane dressings

For severe disease or failure with topical treatments:

-steroids: 60-120 mg prednisone per day

pulse methylprednisolone For refractory cases:

dapsone, thalidomide, mycophenolate, cyclosporine, azothioprine, IVIG

Surgery: split thickness skin grafts; also must use systemic immunosuppression

Conclusions PG-fortunately uncommon Diagnosis of exclusion because of the lack

of any specific diagnosis certainties Big mimicker Treatment often requires major

immunosuppression Keep it in your differential!