Necrobiosis lipoidica diabeticorum (NLD) is an uncommon but distinctive skin condition that affects less than 1 percent of people with diabetes but is strongly associated with it — about half of NLD patients have diabetes. The lesions appear as yellowish-brown atrophic plaques with sharply demarcated borders and visible telangiectasias, typically on the anterior shins. Roughly 30 percent ulcerate, often after minor trauma. Treatment options include topical or intralesional corticosteroids, topical tacrolimus, light therapy, pentoxifylline, and dedicated wound care for ulcers.
What NLD Looks Like
- Earliest lesion. Small reddish-brown papule or patch, often on the shin
- Mature plaque. Yellow-brown to orange-brown center; reddish-purple border; sharply demarcated edges
- Atrophic appearance. Center of the plaque thins, becoming shiny and translucent; telangiectasias (tiny dilated capillaries) become visible through the skin
- Size. Lesions can be 1 to 10+ cm; coalescence into large plaques is common
- Location. Anterior shin (pretibial) in about 85 percent of cases; less commonly forearms, abdomen, scalp, face
- Distribution. Usually bilateral but asymmetric in size and shape
- Sensation. Many lesions are mildly hypoaesthetic (reduced sensation) due to small nerve damage; some are tender; many are asymptomatic
- Course. Slow expansion over months to years; spontaneous resolution is rare
How Common Is It and Who Gets It
| Population | Approximate Prevalence/Distribution |
|---|---|
| People with diabetes | Less than 1 percent (0.3 to 1.6 percent in studies) |
| NLD patients with diabetes | About 50 percent at time of diagnosis |
| NLD patients who develop diabetes later | Additional fraction over years |
| Female-to-male ratio | Approximately 3 to 1 |
| Typical age at onset | 30s to 40s, though any age possible |
| Type 1 vs Type 2 diabetes | More commonly reported in type 1 |
What Causes It
- Microangiopathy. Small blood vessel damage similar to other diabetic microvascular complications
- Collagen degeneration. Granulomatous inflammation around degenerating collagen bundles in the dermis (“necrobiosis”)
- Immune-mediated component. Granuloma formation suggests an immune response to altered collagen
- Trauma. Minor trauma may trigger or worsen lesions (Koebner-like phenomenon)
Symptoms and Complications
Cosmetic and Local
- Distinctive appearance can cause embarrassment and avoidance of shorts, skirts, and beach activities
- Itching or burning in some lesions
- Reduced sensation in mature plaques
- Slowly progressive enlargement over years
Ulceration
- About 30 percent of NLD plaques will ulcerate
- Often triggered by minor trauma — a bump, an insect bite, a scratch
- Ulcers are typically slow to heal because of the underlying atrophic, poorly vascularized tissue
- Risk of secondary bacterial infection
- Rare cases of squamous cell carcinoma arising in chronic NLD ulcers
Psychological Impact
- Visible skin changes on legs affect self-image and clothing choices
- Younger patients and women are often most affected
- Mental health support is helpful when impact is significant — see diabetes and depression and diabetes and anxiety
Diagnosis
- Clinical recognition. The classic yellow-brown atrophic plaque with telangiectasias on a shin is usually distinctive enough for diagnosis
- Dermoscopy. Can highlight telangiectasias and yellowish background
- Biopsy. Reserved for atypical lesions or suspicion of alternative diagnoses; shows palisading granulomas with central necrobiosis of collagen, perivascular lymphocytic infiltrate, and dilated vessels. Take biopsy from the edge, not the atrophic center (high ulceration risk)
- Glucose evaluation. If diabetes not yet diagnosed, check A1C and fasting glucose; consider oral glucose tolerance test
- Microvascular screening. A patient with NLD should have current screening for retinopathy, nephropathy, and neuropathy
Differential Diagnosis
| Condition | Differentiating Features |
|---|---|
| Diabetic dermopathy | Small (5-12 mm), reddish-brown, asymptomatic; see diabetic dermopathy |
| Granuloma annulare | Annular bumps with central clearing, no atrophy or telangiectasias |
| Sarcoidosis | Brown-purple papules and plaques; can mimic NLD; biopsy distinguishes |
| Stasis dermatitis | Medial ankle, edema, varicosities, eczematous changes |
| Erythema induratum | Tender nodules on calves, often ulcerate, tuberculosis association |
| Lipodermatosclerosis | Woody induration of medial lower leg in chronic venous disease |
| Lichen sclerosus | White atrophic patches; different distribution typically |
| Pretibial myxedema | Associated with Graves disease; orange-peel skin, non-pitting edema |
Treatment
First-Line Topical and Local
- High-potency topical corticosteroids. Applied to active edges (red-purple border) under occlusion; avoid applying to the atrophic center to reduce risk of further atrophy and ulceration
- Intralesional corticosteroids. Triamcinolone injected into active edges; careful technique required
- Topical calcineurin inhibitors. Tacrolimus 0.1 percent ointment — useful in atrophic areas where steroids should be avoided
- Wound care for ulcerated areas. Moist wound dressings, debridement of slough, infection control
Phototherapy and Light-Based
- Topical PUVA (psoralen plus UVA). Repeated sessions for non-ulcerated plaques
- Excimer laser. Targeted 308 nm light for selected lesions
Systemic Therapy (for Aggressive or Refractory NLD)
- Pentoxifylline. Improves microcirculation; case series support use
- Hydroxychloroquine. Antimalarial with immunomodulatory effects
- Fumaric acid esters. Used in some European centers
- Nicotinamide. Anecdotal benefit in some patients
- Biologic agents (infliximab, adalimumab, etanercept). Case series for severe ulcerated NLD; specialist use only
- Cyclosporine. Rare cases; specialist setting
Surgical and Procedural
- Surgical excision and grafting is sometimes done for refractory ulcerated areas, with risk of recurrence at graft edges
- Hyperbaric oxygen has been used in selected non-healing ulcerated NLD
What Often Does Not Help
- Tight glycemic control alone does not reliably resolve existing lesions, though it remains important for general health
- Aspirin and dipyridamole — older studies were mixed; not standard therapy
Living With NLD
- Protect the skin. Long pants, shin guards during sports, careful with furniture corners and pet scratches — minor trauma is the most common ulceration trigger
- Moisturize. Daily emollients support the fragile atrophic skin
- Sun protection. Reduces additional pigmentation and protects thinned skin
- Camouflage cosmetics. Specialized concealers, self-tanners, or pigmented sunscreens can help cosmetically
- Inspect lesions regularly. Any new break in the skin warrants prompt attention before it becomes a chronic ulcer
- Smoking cessation. Improves microvascular flow and wound healing if ulcers develop
- General diabetes care. Maintain A1C in your individualized target range — see A1C levels and treatment
When to Seek Evaluation
- New atypical skin lesion on the shin or elsewhere
- Suspected NLD if you have not been diagnosed
- Rapid expansion of an existing plaque
- Ulceration of any size — call within 24 hours
- Signs of infection — redness, warmth, drainage, fever
- Persistent pain or sensitivity changes
- Long-standing ulcer that develops a raised or atypical area — rare squamous cell carcinoma risk
- Emotional impact affecting daily life — mental health support is appropriate
Related Reading
See the companion piece on diabetic dermopathy for the more common benign shin condition, diabetic wound healing for ulcer management, and the American Academy of Dermatology for general dermatology resources.
The Bottom Line
Necrobiosis lipoidica diabeticorum is a rare but distinctive skin condition that signals a strong association with diabetes — about half of NLD patients have it. The yellow-brown atrophic plaques with telangiectasias on the shins are recognizable clinically, though biopsy is occasionally needed. About 30 percent ulcerate, often after minor trauma, so protection of the affected skin is central to management. Treatment options include topical corticosteroids and tacrolimus, light therapy, pentoxifylline, and dedicated wound care for ulcers. Glycemic control is important for general health but does not reliably improve existing lesions. Anyone with NLD should have current microvascular screening for retinopathy, nephropathy, and neuropathy, and should seek prompt care for any new ulceration or signs of infection.
