Chapter 193: Pemphigus

PATIENT STORY

A young man presented with painful blisters on his face and mouth (Figure 193-1). The patient was referred to dermatology. Suspecting pemphigus vulgaris (PV), the physician performed shave biopsies for histopathology and direct immunofluorescence of facial vesicles/bullae to confirm the presumed diagnosis. The patient was started on 60 mg of prednisone daily until the pathology confirmed PV. Steroid-sparing therapy was then discussed and started 2 weeks after initial presentation.

INTRODUCTION

Pemphigus is a rare group of autoimmune bullous diseases of the skin and mucous membranes characterized by flaccid bullae and erosions. The word pemphigus is derived from the Greek word pemphix, which means bubble or blister. The three main types of pemphigus are PV, pemphigus foliaceus (PF), and paraneoplastic pemphigus (PNP). Pemphigus causes significant morbidity and mortality and can be fatal if left untreated. Although pemphigus is not curable, it can be controlled with systemic steroids and immunosuppressive medications. These medications can be lifesaving, but they also place pemphigus patients at risk for a number of complications.

EPIDEMIOLOGY

Epidemiology of the three major types of pemphigus:

• PV (Figures 193-1, 193-2, 193-3, 193-4).

  • Most common form of pemphigus in the United States.

  • Annual incidence is 0.75 to 5 cases per 1 million.¹

  • Usually occurs between 30 and 50 years of age.²

  • Increased incidence in people of Ashkenazi Jewish and Mediterranean origin.²

  • Pemphigus vegetans is an even rarer vegetative variant form of PV (Figures 193-5 and 193-6).

• Pemphigus foliaceus (Figures 193-7, 193-8, 193-9, 193-10)—Superficial form of pemphigus.

  • More prevalent in Africa (Figures 193-11 and 193-12).¹

  • Variant forms include pemphigus erythematosus (resembles the malar rash of lupus erythematosus) and fogo selvagem.

  • Fogo selvagem is an endemic form of PF seen in Brazil and affects teenagers and individuals in their twenties.¹

• Paraneoplastic pemphigus.

  • Onset at age 60 years and older.

  • Associated with occult neoplasms, commonly lymphoreticular, (e.g., non-Hodgkin lymphoma and chronic lymphocytic leukemia).

  • Can also be associated with benign neoplasms, such as thymoma and Castleman disease (angiofollicular lymph node hyperplasia).²