A recently described cutaneous fibrosing disorder could be mistaken for scleroderma, but there are some key differences, said Dr. Collier.
Worldwide, there have been only 170 cases of nephrogenic fibrosing dermopathy (NFD) reported since it was first described in 1997, he said. Yet “I think it's far more common than we're led to believe,” he added.
The typical presentation of NFD consists of acute, lumpy, plaquelike indurations involving the lower limbs and occasionally the upper limbs and torso, he said.
Usually, scleroderma starts on the hands and face. But in NFD, these are almost always spared, he said.
The most common distribution of NFD skin presentation is between the ankles and the mid-thighs and between the wrists and mid-upper arms bilaterally, he said. Skin-colored to erythematous papules coalesce into brawny plaques with a peau d'orange appearance. There is a distinctive, irregular edge with amoeboid projections and islands of sparing within the indurated plaque. Eventually, the skin becomes markedly thickened and woody. Pruritis and causalgia are prominent features.
Unlike scleroderma, NFD often causes severe sharp pains in the affected areas, and renal insufficiency is necessary for the diagnosis.
The biopsy will show deposits of collagen and elastin—spindle cells, dendritic cells, and mucin deposits—“which is different from what we see in scleroderma.”
Although NFD was initially thought to be only a cutaneous disease, there now appears to be a severe myopathic component. Joint contractures may develop within days or weeks of onset, likely resulting from facial and muscle fibrosis, Dr. Collier noted.
The abrupt emergence of this disease suggests that toxic exposures, infectious agents, or medical techniques may be involved.
NFD plaques typically take on a peau d'orange appearence. Courtesy Dr. David H. Collier