Pemphigus is a group of severe, chronic, recurrent blistering skin diseases.

bubble_chart Etiology

The etiology of this disease remains unclear. Currently, most scholars believe it may be an autoimmune disorder, as indirect immunofluorescence testing has detected specific antibodies (also known as pemphigus antibodies) in patients' serum that target intercellular substances in epidermal spinous cells, primarily IgG. The titer of pemphigus antibodies in the serum correlates with the severity of the disease. The site where pemphigus antibodies react histopathologically corresponds to the lesion site of pemphigus (where acantholysis occurs). These antibodies act on the intercellular junctions in the epidermis.

bubble_chart Clinical Manifestations

On normal skin or erythema, flaccid blisters appear, characterized by being extremely prone to rupture and forming greasy crusts, with localized or extensive exfoliation and a foul odor. Sometimes, the affected skin becomes red and swollen with leaf-like crusts, resembling exfoliative dermatitis lesions. Nikolsky's sign is positive.

The lesions mostly occur on the head, face, chest, and back. The oral mucosa is rarely involved. The patient experiences cutaneous pruritus, and systemic symptoms vary in severity.

bubble_chart Diagnosis

1. Flaccid bullae with crusting or refractory erosions on the skin.
2. Mucous membranes, especially oral mucous membranes, are often early symptoms of pemphigus vulgaris.
3. Nikolsky's sign is positive.
4. Scrapings from the base of the bullae may reveal pemphigus cells (Tzanck cells).
5. Immunofluorescence examination:

   a. Direct method: IgG and C3 deposits are found between epidermal cells in the lesional area. Additionally, approximately 25-30% of patients may show IgA and IgM. In non-lesional areas, about 60% have IgG and C3 deposits.

   b. Indirect method: Approximately 100% of patients' sera contain pemphigus antibodies. The antibody titer is generally parallel to the disease severity.

   In addition to the above findings, pemphigus erythematosus shows positive antinuclear antibodies and IgG and C3 deposits at the dermo-epidermal junction, similar to lupus erythematosus.

6. Pathology: Intraepidermal acantholytic bullae. Acantholysis, observed under electron microscopy, reveals dissociation of the desmosomal core, leading to loss of intercellular adhesion. This is also the pathological basis of Nikolsky's sign.

The base of the bullae shows villus formation, with grade I inflammatory cell infiltration in the dermis.

In addition to the above changes, pemphigus vegetans exhibits epidermal hyperplasia with pseudoepitheliomatous changes and multiple eosinophilic microabscesses within the epidermis.

In pemphigus foliaceus and pemphigus erythematosus, acantholytic bullae occur in the superficial layers of the epidermis (subcorneal or within the granular layer).

bubble_chart Treatment Measures

1. Corticosteroids: Prednisolone or Prednisone is primarily used at 40-60mg/day. Alternatively, Hydrocortisone 300mg can be administered intravenously depending on the condition. After the condition is controlled, the dosage should be gradually and systematically reduced until a maintenance dose of 10-15mg/day of Prednisolone or Prednisone is reached.
2. Immunosuppressants: Cyclophosphamide 100mg/day (approximately 2mg per kilogram) is the main choice. The dosage should be gradually reduced to zero once the condition stabilizes. Alternatively, Azathioprine 50mg twice daily can be used.
3. Gold Therapy: For cases resistant to conventional treatments, especially persistent mucosal erosions, this therapy can serve as a supplementary treatment. Gold thioglucose is primarily used, administered via intramuscular injection once a week or every other day, with gradual dose increases.

   Week 1→4: 10mg per dose. Week 5→8: 25mg per dose. Week 9→12: 50mg per dose. After Week 13: 50mg per dose. The total cumulative dose can reach up to 1000mg.

4. Plasmapheresis: The goal of this therapy is to remove abnormal plasma components, particularly antibodies, immune complexes, and other harmful non-diffusible substances, replacing them with fresh plasma from healthy donors, fresh frozen plasma, or albumin preparations. This method serves as a supplementary therapy for those experiencing side effects due to corticosteroids. 1000ml/day for 3 consecutive days constitutes one course, with one course per week for a total of 3 courses.
5. Chinese Medicine Treatment:

   a. Intense Toxin-Heat Type: The method focuses on clearing heat and removing toxins, cooling blood, and clearing the nutrient aspect. The formula includes charred Unprocessed Rehmannia Root, charred Lonicera Flower, Lotus Plumule, Lalang Grass Rhizome, Mongolian Snakegourd Root, Viola, Raw Gardenia, Chinese Manyleaf Paris Rhizome, Raw Liquorice Root, Coptis Rhizome, Raw Gypsum. For persistent high fever, add Rhinoceros Horn 0.5g; for dry stool, add Rhubarb Rhizoma.

   b. Heart Fire and Spleen Dampness Type: The method focuses on clearing the heart and reducing fire. The formula includes Poria, White Atractylodes Rhizome, Atractylodes Rhizome, Scutellaria, Unprocessed Rehmannia Root, Alisma, Raw Liquorice Root, Forsythia, Sodium Sulfate, Rush Pith, Bamboo Leaf, Submature Bitter Orange. For high fever, add Turtle Shell and Raw Gypsum; for intense heart fire, add Lotus Plumule and Coptis Rhizome; for oral mucosal erosions, add Trollius and Genista; for dry stool, add Rhubarb Rhizoma.

   c. Dual Deficiency of Qi and Yin Type: The method focuses on replenishing qi and nourishing yin, clearing and releasing remnant toxins. The formula includes American Ginseng, Southern Glehnia, Dendrobium, Black Scrophularia Root, Finger Citron, Raw Astragalus, Dried Unprocessed Rehmannia Root, Salvia, Lonicera Flower, Dandelion, Ophiopogon and Liriope, Polyghace Seche.

6. Depending on the condition, supportive therapy and anti-infection treatment should be strengthened.
7. Local Therapy: Exposure is preferred. Anti-infection coating agents or 2% Gentian Violet solution can be used. For oral mucosal lesions, medications containing surface anesthetics and antibiotics, such as 1% Dyclonine or 1% Neomycin solution for gargling, can be applied.