Nodular lesions of panniculitis may become confluent, thus giving the impression of diffuse induration; yet it is most likely that one would identify one or few discrete subcutaneous nodules in the vicinity of a large lesion. Pretibial myxedema, panniculitis, and NL are rather easy to diagnose clinically

NL most often presents as a well-defined plaque that is indurated with characteristic color and rarely presents with diffuse induration. It is the only disorder among the six that may spontaneously ulcerate.

Pretibial myxedema is almost always associated with a known thyroid disorder or that may be easily identified by testing at the time of presentation. Unlike the characteristic colors of panniculitis and NL, the skin overlying lesions of pretibial myxedema tends to be normal in color. Unlike lesions in other disorders of this group, lesions of pretibial myxedema tend to be soft or doughy and may show a peau d’orange surface, hypertrichosis, and hyperhidrosis. Massive deposition of mucin focally may result in nodular infiltration within the plaques.