Degos' disease has been considered universally to be a specific condition that affects the skin, gastrointestinal tract, central nervous system, and, less commonly, other organs. Thrombosis followed by infarction has been regarded as essential to the development of signs and symptoms wherever the disease expresses itself. Certain morphologic features are said to be pathognomonic of Degos' disease and unique to it, perhaps most notable being cutaneous "porcelain-white scars" rimmed by erythema and telangiectasis. For years the disease was considered to be fatal invariably. Because there are no laboratory findings pathognomic of Degos' disease, the diagnosis, perforce, must be based on morphologic attributes, namely, gross (clinical) and microscopic (histopathologic) ones. In the skin, the former are pink papules that end as white atrophic scars associated with telangiectasias, and the latter is a wedge-shaped zone of sclerosis that extends from the epidermis through the reticular dermis and in company with it are deposits of mucin, alteration of vessels by proliferation of endothelial cells, a thickened wall and thrombosis. Sparse infiltrates of lymphocytes are confined to perivascular locale.

Although Degos' disease, as its synonym malignant atrophic papulosis denotes, was long considered to be "malignant" in the sense that it eventuates in death, it now is known that some patients may have a "benign" protracted course typified seemingly entirely by skin lesions and no compromise of longevity. About 4% to 15% of patients are thought to have the "benign" form of the disease, but the percentage could be higher because patients who have only skin lesions do not always seek medical attention.

We view Degos' disease as analogous to lupus erythematosus, to wit, a pathologic process that fundamentally is systemic with proclivity to involve several organs, e.g., the gastrointestinal tract, the brain, and the skin, but that varies greatly in regard to which organ(s) are affected and how severely, from extensive involvement of vital organs and death, e.g., the kidney in lupus erythematosus and the gastrointestinal tract in Degos' disease, to what seems to be involvement of the skin alone, e.g., discoid lesions of lupus erythematosus and porcelain-white scars of Degos' disease. In the course of years, what at first was thought to be cutaneous disease alone may be accompanied by overt signs of systemic disease; in fact, the process really was systemic from the outset. There is no way to predict which patients who present themselves with skin lesions of lupus erythematosus and of Degos' disease will in time develop signs and/or symptoms of obvious systemic involvement.

What particularly intrigues us is not only the analogy between lupus erythematosus and Degos' disease, but what we regard to be a relationship between lupus erythematosus and Degos' disease. Skin lesions of Degos' disease sometimes display findings indistinguishable histopathologically from those of lupus erythematosus (sparse perivascular infiltrates of lymphocytes, copious quantities of mucin in the reticular dermis, sclerosis in the upper part of the dermis, a smudged appearance of the dermo-epidermal junction, a thinned epidermis devoid of rete ridges, and compact orthokeratosis) and some patients believed to have Degos' disease by virtue of stereotypical morphologic features and distribution of lesions, actually have lupus erythematosus by virtue of unquestionable signs immunologically. The evidence for that circumstance is convincing.

Since 1969, patients with what seemed to be Degos' disease have been noted to have other "collagen vascular diseases," such as systemic lupus erythematosus (4 patients), progressive systemic sclerosis (1 patient), dermatomyositis (1 patient), and rheumatoid arthritis (1 patient), as well as having positive lupus anticoagulant and/or anticardiolipin antibodies (approximately 6 patients) and sclerosing panniculitis like that of lupus profundus (1 patient). One patient had Crohn's disease and two suffered from chronic immunodeficiency (AIDS and drug related immunosuppression).

We do not agree with those who assert that despite a patient having a clinical picture just like that of Degos' disease, that patient does not have the disease, but rather "Degos-like lesions."⁵⁶ On the contrary, we think that Degos' disease is not a specific disease, but a distinctive morphologic pattern analogous to leukocytoclastic vasculitis, urticaria, erythema multiforme, erythema nodosum, nodular vasculitis, Sweet's syndrome, pyoderma gangrenosum, granuloma annulare, morphea (including lichen sclerosus et atrophicus), and Reiter's syndrome (which is psoriasis brought about by different infectious agents that affect different systems). Each of those conditions has very distinctive, easily recognizable clinical and histopathologic findings for which there are a variety of causes. So, too, it is for Degos' disease. We also think that in succeeding years, "diseases" like psoriasis, lichen planus, and pityriasis rubra pilaris, as well as lupus erythematosus, dermatomyositis, and rheumatoid arthritis, will be thought of as patterns of pathologic changes induced by many different factors, rather than as diseases with a single specific cause.

Degos' disease was described in 1942 and LE cells were recognized in 1943, but it was not until 1952 that a method was found for isolating LE cells from peripheral blood. Antinuclear antibodies and anti-DNA antibodies were discovered in 1954 and 1957, respectively. Only in the 1960's did laboratory methods for detection of these antibodies become available readily. The "lupus band test" was introduced in 1963.⁶² In the absence of these advances, patients with a diagnosis of Degos' disease made prior to the 1960's could not be assessed methodically for lupus erythematosus and other collagen vascular diseases. Had that been possible, we believe that a connection would have been established sooner between lupus erythematosus and Degos' disease

Antiphospholipid antibodies could be a link between Degos' disease and lupus erythematosus. Antiphospho-lipid antibodies have been demonstrated in some patients with Degos' disease,^12,27,47 but those autoantibodies have not been found consistently in patients with that disease. About half of all patients with Degos' disease were reported on before 1974,^11,12 but it was not until the early 1980's that solid phase assays were devised for detection of antiphospholipid antibodies.⁶³ Moreover, the term anticardiolipin syndrome was introduced in 1985 by Hughes et al.,⁶⁴ and the term antiphospholipid syndrome was proposed by Harris et al. in 1987.⁶⁵ For these reasons, most of the patients with Degos' disease reported on to date have not been screened for anticardiolipin antibodies and for lupus anticoagulant activity. Had that been done, we think that many of those patients would have been found to have antiphospholipid antibodies.

In short, we do not conceive of Degos' disease as a specific disease, but as a distinctive pattern expressive of different pathologic processes, chief among them lupus erythematosus. Patients with skin lesions typical of Degos' disease should be assessed for evidences of lupus erythematosus and other collagen vascular diseases, and for the presence of antiphospholipid antibodies. It is likely that many patients thought to have Degos' disease will prove to have lupus erythematosus.