DrMihm.com Case File

 Search Dr.Mihm.com
 

Necrosbiosis Lipoidica - Submitted on: Sunday December, 06, 2009
Contributed by:Shaofeng Yan, MD, PhD, N/A
Necrobiosis is an idiopathic granulomatous disease

Definition:
Necrobiosis lipoidica is an idiopathic granulomatous disorder belonging to the palisading granulomatous group. In at least 55% of the cases it is associated with diabetes. Histologically it is characterized by involvement of the entire skin..

Clinical Features:
Necrobiosis lipoidica commonly presents as yellow indurated atrophic and sclerotic plaques of the shins. It is , irregularly and sharply demarcated, and may be complicated by ulceration. It was originally called “necrobiosis lipoidica diabeticorum”. Although some cases are associated with diabetes mellitus, it is not peculiar to diabetes (1). The lesion may also occur on other sites, particularly forearms, hands, and trunk. In one series, only 11% of patients with necrobiosis lipoidica had diabetes at presentation, with further 11% developed impaired glucose tolerance/diabetes over 15 years(2). The incidence of necrobiosis lipoidica in diabetics is less than 1%(3).

Histology:
Figures
(Click on an image for a larger view)
Figure 1. There is involvement of the full thickness of the dermis.
Figure 2. The inflammatory infiltrate consists of histiocytes, multinucleated giant cells, lymphocytes and plasma cells.
Figure 3. Deep perivascular and periadnexal lymphoplasma cell infiltrate.
Figure 4. Dermal sclerosis is a typical finding in old atrophic lesions.
The histological changes in necrobiosis lipoidica involve the full thickness of the dermis (figure 1) and often extend to the subcutis with sandwich like horizontal layers of necrobiotic collagen alternating with inflammatory cell infiltrate of lymphocytes, histiocytes, multinucleated giant cells and plasma cells (figure 2 and 3). Small and large vessels may show intimal proliferation and thickening of the vessel wall. Granulomatous inflammation may impinge on the large vessels and together with microangiopathy lead to fibrosis and scar formation (figure 4). The main histological differential diagnosis of necrobiosis lipoidica is granuloma annulare which also shows palisaded necrobiotic granuloma but usually only focally involves the dermis with relative normal intervening areas. An increase of dermal mucin is a feature commonly seen in granuloma annulare. Plasmacytosis and fibrosis are not usually seen in granuloma annulare. Histological features favoring necrobiosis lipoidica are extensive and diffuse involvement of the dermis with horizontally oriented linear array, large number of giant cells, prominent deep plasma cells and lymphoid aggregates around sweat glands, pronounced vascular changes and dermal fibrosis. A very important observation is the finding of atypical plasma cells or very dense plasma cell infiltration. In such cases the lesion is associated with plasma cell dyscrasia and circulating monoclonal antibodies. We always suggest JKappa and Lambda studies when there is any suspicion of plasma cell atypia.


Treatment:
Treatment for necrobiosis lipoidica (NL) is not very effective partially because the exact etiology remains unknown.

Bibliography:
  • 1. Weedon, Skin Pathology, Chapter 7, The granulomatous reaction pattern: 202-204
  • 2. O’Toole EA, et al. Necrobiosis lipoidica: only a minority of patients have diabetes mellitus. Br J Dermato 1999:140:283-286
  • 3. Muller SA, et al. Necrobiosis lipoidica diabeticorum. A clinical and pathological investigation of 171 cases. Arch Dermatol 1966; 93:272-281
     

    Back To Cases

     


    [Home] [Observations] [Cases] [Glossary] [Who We Are] [Contact Us] [Links] [Search]


     

    Copyright © 2001-2002 Martin C. Mihm, Jr.
    All  rights reserved worldwide.