necrobiosis lipoidica diabeticorum [NLD]

Etiology

• diabetes mellity
• often occurs in association with diabetic nephropathy &/or diabetic retinopathy

Epidemiology

• < 1.0% of diabetics
• > 66% of patients with NL have diabetes
• > 90% of remainder develop glucose intolerance with glucocorticoids

Clinical manifestations

• well demarcated, multicolored plaques (orange,red, yellow, brown) with serpinginous borders evolving slowly over a period of months
• ulceration commonly occur within plaques
• telangiectasias seen within plaque
• lesions persist for years
• burned out lesions appear as tan-brown scars
• lesions generally symmetric
• 80% of lesions pretibial, but may also appear on feet, arms, trunk, face, scalp or in a generalized distribution

* images

Laboratory

• diabetic assessment
  • serum glucose
  • hemoglobin A1c
  • glucose tolerance test a & b are normal
• biopsy
  • immunofluorescence shows presence of immunoglobulins & complement C3
  • granulomatous infiltration in lower dermis
  • microangiopathy with endothelial thickening & focal deposits of PAS+ material

Differential diagnosis

• sarcoidosis
• granuloma annulare (frequently coexists with NL)
• xanthoma
• pretibial myxedema
  • history of hyperthyroidism Graves disease)
  • elephantiasis may develop in pretibial myxedema

Management

• topical corticosteroids under occlusion
• intralesional triamcinolone 5mg/mL generally arrests yellow lesions
• wet to dry dressings for ulcerations

More general terms

• diabetes mellitus complication
• necrobiosis lipoidica

Additional terms

• diabetes mellitus
• granuloma annulare (GA)