Papules grow to cover patches below knees - Clinical Advisor

Papules grow to cover patches below knees

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  • CA0311DermClin_Case2

A white woman aged 45 years presented with multiple plaques on the anterior and lateral aspects of her lower legs. The lesions began as erythematous papules that enlarged over the past few years to form plaques with raised borders and depressed centers. The patient reported no pain or pruritus.

Examination showed multiple well-demarcated plaques with raised, red borders and atrophic, yellow centers with multiple telangiectasias. The patient’s medical history was significant only for abnormal blood sugar eight years prior to presenting to the clinic. She had not been evaluated for diabetes since that time.
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The patient was diagnosed with necrobiosis lipoidica diabeticorum (NLD), a chronic skin disorder of unknown etiology, characterized by degeneration of collagen, granulomatous inflammation, blood-vessel-wall thickening, and sclerosis in the dermis. It is clinically significant because two thirds of patients who...

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The patient was diagnosed with necrobiosis lipoidica diabeticorum (NLD), a chronic skin disorder of unknown etiology, characterized by degeneration of collagen, granulomatous inflammation, blood-vessel-wall thickening, and sclerosis in the dermis. It is clinically significant because two thirds of patients who present with NLD have diabetes mellitus.1 However, no association has been made between diabetes control and the severity or the progression of NLD. This is reflected in the fact that only 0.3% to 0.7% of individuals with diabetes develop NLD.2 NLD occurs three times more often in women and most often strikes in the third or fourth decade of life.3

NLD commonly presents as one or several lesions on the anterior or lateral aspects of the lower legs as well as the back of the hands or the forearms. Lesions are usually bilateral. In some instances, NLD may present on the arms, face, or trunk as well. However, only 1% of patients with NLD have lesions exclusively outside of the lower extremities.1 The lesions begin as small, discrete, red or violaceous papules that evolve into larger plaques. These plaques typically have a discrete red border with central depression. The center becomes yellowish and atrophic with multiple telangiectasias visible. The plaques are asymptomatic, but up to 35% of cases progress to shallow, painful ulcers.3 Histopathologically, the NLD presents with interstitial and palisaded granulomas involving the subcutaneous tissue and dermis. The infiltrate in the reticular dermis primarily consists of CD4 lymphocytes.4

The differential diagnoses of early NLD include Crohn’s disease, ulcerative colitis, granuloma annulare, and sarcoidosis.5 Older NLD lesions are more distinct and are easier to differentiate from the other two entities. There have also been cases of NLD co-occurring with sarcoid or granuloma annulare.1

Treatment of NLD can be difficult. Current therapies have limited efficacy or carry significant side effects.6 Most are aimed at the microangiopathic and inflammatory nature of the disease. In addition to smoking cessation and diabetes control,7 first-line therapy consists of topical and intralesional glucocorticoids. Systemic corticosteroids have also been used, but the adverse effects and influence on glucose control in diabetes limit their use. Treatment with pulsed-dye lasers can improve the appearance of telangiectasias.7 Other reported treatments have included pentoxifylline, aspirin, chloroquine, cyclosporine,3 ticlopidine, nicotinamide, clofazimine, psoralen UVA, and etanercept.7 Recently, thalidomide has also been reported to treat NLD.2 Severe refractory cases may necessitate a split-thickness skin graft.3 Spontaneous remission is reported in approximately 20% of patients.4

Because of the risk of further skin atrophy, this patient was not treated with corticosteroids; thalidomide treatment was suggested instead. The patient was lost to follow-up.

Dr. Creed is a dermatology resident at the University of Texas Medical School at Houston. Dr. Hsu is professor of dermatology at Baylor College of Medicine in Houston. Neither author has any relationships to disclose relating to the content of this article.


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References

1. Shapiro PE. Noninfectious granulomas. In: Elder DE, Elenitsas R, Johnson BL, Jr, Murphy GF, eds. Lever’s Histopathology of the Skin. 8th ed. Philadelphia, Pa.: Lippincott Williams & Wilkins; 1997:330-333.

2. Kukreja T, Petersen J. Thalidomide for the treatment of refractory necrobiosis lipoidica. Arch Dermatol. 2006;142:20-22. 

3. Ahmed I, Goldstein B. Diabetes mellitus. Clin Dermatol. 2006;24:237-246.

4. Körber A, Dissemond J. Necrobiosis lipoidica diabeticorum. CMAJ. 2007;177:1498.

5. Lowitt MH, Dover JS. Necrobiosis lipoidica. J Am Acad Dermatol. 1991;25:735-748.

6. Zhang KS, Quan LT, Hsu S. Treatment of necrobiosis lipoidica with etanercept and adalimumab. Dermatol Online J. 2009;15:12.

7. Zeichner JA, Stern DW, Lebwohl M. Treatment of necrobiosis lipoidica with the tumor necrosis factor antagonist etanercept. J Am Acad Dermatol. 2006;54:S120-121.

All electronic documents accessed February 15, 2011.

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