| Gary M. White & Neil H. Cox |
| Diseases of the Skin |
13 |
Collagen Vascular Disease
|
INTERSTITIAL GRANULOMATOUS DERMATITIS
Etiology and pathogenesis
This recently described rare entity is briefly discussed, as it has both striking clinical features and also a strong relationship with collagen vascular disease (especially with rheumatoid arthritis) or with the presence of autoantibodies (especially ANA, rheumatoid factor, and antithyroid antibodies).
Clinical
The main clinical and histologic features are apparent from the varied names that have been applied to this disorder: interstitial granulomatous dermatitis with plaques, interstitial granulomatous dermatitis with cutaneous cords and arthritis, and palisaded neutrophilic granulomatous dermatitis (of immune complex disease). The skin lesions are irregular plaques or linear bands, cutaneous and/or subcutaneous, often bizarre in appearance; they are typically symmetric, red-brown or violaceous, and situated on the flanks or in body folds.
Differential diagnosis
Clinically, the lesions may resemble morphea, lymphoma, or annular erythema; histologically, any granulomatous disorder may need to be considered (Ch.11). Disorders that may be similar on both clinical and histologic grounds include sarcoidosis (Fig.13.58), granuloma annulare, and granulomatous mycosis fungoides.
Fig. 11.58 Nodules and a subcutaneous cord; the differential between interstitial granulomatous dermatitis versus subcutaneous sarcoidosis could not be made with certainty, but lesions resolved spontaneously. (Courtesy of Dr. L. Barco.) |
Treatment
Non-steroidal antiinflammatory drugs, oral corticosteroids, and immunosuppressive agents such as ciclosporin may be useful.
White/Cox: Diseases of the Skin, 2ed.(c) 2006, Elsevier Inc. All rights reserved.
