Unfortunately, it takes a peculiar "internist" to be interested in an "external" disease. Pemphigus is one of those rare disorders with large blisters and erosions that seem to be 100% external (mucocutaneous), yet cause patients to die; often the reason why the patient died is not disclosed at autopsy. This is vexing to internists and pathologists, but the dermatologist is likely to nod and say "You see, I keep telling you that a person can't get along without his skin. Why don't you write 'cutaneous failure' on the death certificate?"
Dr. Lever's book is excellent and should be well received by dermatologists and pathologists. But I suspect that internists will "stay away from it in droves" because it details problems that they view with so little interest. Some textbooks of general medicine devote a paragraph to pemphigus but make no attempt to distinguish the several clinical forms, nor the disorders