Clinical features of pemphigus

Abstract

Pemphigus is an autoimmune, blistering disease that affects the skin and mucous membranes. 1 It affects all ages. Pemphigus has been reported in children and young adults. The mean age of onset is the sixth decade in most large series, the range being 12–88 years. 2–4 The majority of patients are often in their fourth, fifth, and sixth decades. Thus it appears that pemphigus attacks individuals at the peak of their adult lives. This often has a deleterious effect on the psychology of the patient and the patient's family. Age of anset is important because the prognosis in older patients is not as good as that in younger patients. 5 Pemphigus affects men and women equally. The incidence is slightly higher in Jewish women than men. 6 When large series are compared, and patients below the age of 20 are studied, it appears that there is a predilection for women in that group. 7 The exact incidence of pemphigus is unknown. Since it is not a reportable disease it is difficult to establish the incidence. This reproblem is further compounded by the fact that several drugs are now believed to induce pemphigus (Chapter 4). The establishment of a registry would greatly facilitate the study not only of incidence but other epidemiological features and clinical perspectives as well. In 1941, less than 1% of all cases seen in a large New York City hospital dermatology clinic accounted for pemphigus 6; however, at that time, pemphigus was not differentiated from other blistering diseases. 8 In 1976 in southern Arizona, the incidence was reported to be 0.5 cases per 100,000 population per year. 9 In 1977 in a study from Hartford County in Connecticut, the annual incidence was 0.42 cases per 100,000 people in general. 10 In the same area, the incidence was 3.2 per 100,000 in the Jewish population. It is generally believed that the incidence is significantly higher in patients of Jewish descent or origin. In a study from Jerusalem, the incidence was reported to be 1.62 cases per 100,000 population. 11 Pemphigus has been reported worldwide, and it affects all races. It is important to emphasize that pemphigus is a rare disease. It is nonetheless one of the few potentially fatal skin diseases. Early diagnosis is often associated with good response to therapy and a better prognosis. Direct and indirect immunofluorescent studies have greatly facilitated the diagnostic armamentarium of the clinician. The availability of these tests by mail has increased their practical utilization. There are four described variants of pemphigus: (1) pemphigus vulgaris, (2) pemphigus vegetans, (3) pemphigus foliaceus, and (4) pemphigus erythematosus. The four variants have different clinical presentations. The clinical presentation is dissimilar insofar as that each variant can be clinically differentiated. If the right kind of lesion is biopsied, they can frequently be differentiated histologically. The four variants can also be differentiated in most cases on direct immunofluorescence. On indirect immunofluorescence, the staining pattern is quite similar. It is universally agreed that pemphigus vegetans is a variant of pemphigus vulgaris. 12 Similarly, pemphigus erythematosus is considered a variant of pemphigus foliaceus. 12