CHICAGO — Few physicians would be fooled nowadays by gadolinium-induced nephrogenic systemic fibrosis, but there are other diseases that can masquerade as scleroderma.
The precise diagnosis of sclerodermalike illnesses is important because even though many of them are called scleroderma, they are different from systemic sclerosis in their treatments and outcomes, Dr. Virginia Steen said at a symposium sponsored by the American College of Rheumatology.
The diagnosis is most often based on the distribution and clinical characteristics of skin findings, as biopsies don't always differentiate types of scleroderma. She recommended watching for the following four conditions:
▸ Lipodermatosclerosis is one condition that physicians often fail to think of as a scleroderma mimic. Also known as hypodermatitis sclerodermaformis, it refers to localized chronic inflammation and fibrosis of the skin and subcutaneous tissues of the lower leg. In the acute stage, the leg is inflamed and warm, the skin is very tight, and cellulitis may be present. The ankle and toes are not involved.
In its chronic stage, there is induration, contraction of the skin and subcutaneous tissues, and irregular depressions that can look almost identical to lower-leg scleroderma, she said.
The leg eventually resembles an inverted champagne bottle, in which the upper half remains edematous and has a much greater circumference than does the lower sclerotic portion.
Lipodermatosclerosis is sign of severe end-stage venous insufficiency, and should be differentiated from scleroderma, cellulitis, superficial thrombophlebitis, and erythema nodosum. The diagnosis is made from clinical observation, but direct immunofluorescence of early and late lesions has been used to show dermal pericapillary fibrin deposits.
If left untreated, lipodermatosclerosis can progress to ulceration, atrophy blanche, or shortening of the Achilles tendon. Treatment involves weight loss, controlling the underlying disease, and emphasis on support stockings that may need to be specially made, said Dr. Steen, who is professor of medicine and director of the rheumatology fellowship program at Georgetown University in Washington.
Topical steroids are useful if the skin is inflamed, and antibiotics are recommended for cellulitis.
▸ Scleredema tends to target the upper body without affecting the lower extremities. The skin on the neck and face thicken and harden; severely affected patients are unable to wrinkle their foreheads or open their mouths. In most patients, the shawl sign is present, with skin involvement over the chest and arms, she said.
Pathologic features include swollen collagen with clear spaces and accumulation of hyaluronic acid and glycosaminoglycans. Although scleredema is commonly associated with diabetes, it can also occur after a viral illness.
▸ Eosinophilic fasciitis is a rare disorder characterized by symmetrical and painful inflammation and swelling of the extremities, leading to induration and the characteristic peau d'orange configuration. The palms may be involved, but typically the fingers and toes are spared. Contractures demonstrating the groove sign commonly evolve as a result of induration.
Eosinophilic fasciitis is slightly more common in middle-aged men, but can occur in women and children. It was initially distinguished from systemic sclerosis by the absence of Raynaud's phenomenon, autoantibodies, and visceral involvement, and—unlike systemic sclerosis—it responds to corticosteroids, Dr. Steen said.
Histologically, there are marked eosinophilia and inflammatory infiltrates in the fascia. The extent of the histologic changes depends on the stage of the disease, and thus is not a consistent component of the disease. Aside from marked peripheral eosinophilia, other laboratory features to watch for include an increased erythrocyte sedimentation rate, increased gamma globulin, and an increased aldolase, with a normal creatinine phosphokinase.
Aggressive physical therapy is a key component of treatment, because this and most scleroderma mimics discussed here can cause joint contractures. In eosinophilic fasciitis, low- to moderate-dose prednisone (20–30 mg)—and, if needed, methotrexate as a steroid-sparing agent—can be given, Dr. Steen said.
▸ Diabetic cheiroarthropathy is a syndrome of limited joint mobility in the hands. It is characterized by thickened, tight, waxy hands with sclerosis of the palmar tendon sheaths that noticeably restricts mobility in the proximal interphalangeal joints and metacarpophalangeal joints.
The “prayer sign,” in which the patient will be unable to fully oppose the palmar surfaces of the digits, is a clue to this diagnosis when it is present in a patient with diabetes, said Dr. Steen, who disclosed no relevant conflicts of interest.
The sclerotic plaque on this patient's lower leg is lipodermatosclerosis. Courtesy Dr. Kenneth E. Greer