Toxic Epidermal Necrolysis Or Pressure Bullae

To the Editor.— Plaut and Mirani have recently described a case of toxic epidermal necrolysis due toEscherichia coli1which, in fact, is not TEN but is an excellent example of pressure-induced cutaneous blisters.2 Toxic epidermal necrolysis is a syndrome characterized by acute onset in a patient who was previously well, wide-spread erythema, subsequent epidermolysis (Nikolsky's sign), and rapid healing. Pressure bullae, in contrast, are most often found in comatose patients over pressure points such as elbows, medial and lateral parts of the knees, ankles, and feet. The primary pathogenetic lesion is one of ischemic necrosis with resultant anoxia, and thus, the low flow states and decreased peripheral perfusion induced by shock accentuate the process. The bullae in both syndromes are always sterile initially and become infected only secondary to local factors or systemic sepsis. The histopathologic findings in both are distinctive. Such studies should be done in