口腔学英文课件：Bullous diseases

1、Bullous diseases,pemphigus vulgaris,ulcerative cutaneous lesion in pemphigus vulgaris,Pemphigus Vulgaris,Pemphigus Vulgaris,This is an autoimmune mucocutaneous disease that results in multiple ulcers that are preceded by short-lived blisers. The lesions may be associated with painful debilitation, f

2、luid loss, and electrolyte imbalance, making this a serious disease with potentially profound sequelae.,Etiology and pathogenesis,The triggering event of this autoimmune process is unknown. Circulating autoantibodies (IgG) are directed against an epithelial desmosomal（桥粒） protein known as desmoglein

3、 3. The effect of the autoantibody-antigen reaction is the weakening of desmosomes and loss of cell-to-cell adhesion.,Clinical Features,Oral lesions precede skin lesions in at least half of the patients. In both the skin and mucous membrane, lesions appears as ulcers. The ulcers are proceded by shor

4、t-lived bullae. Orally, lesions affect more than one mucosal region and are usually large and shallow.,Wearing of dental appliances may become difficult because of the production of new blisters（水疱） assosciated with the rubbing of the appliances on the mucosa. In some cases, lesions resemble aphthou

5、s ulcers. A positive Nikolsky sign may be seen.,Clinical Features,Microscopic Feautures,The essential microscopic changes are intraepithelial（上皮内） separation with free-floating or acantholytic（prickle cell layer棘层松解） keratinocytes. Direct immunofluorescent examination of normal-appearing tissue adja

6、cent to lesions exhibits a network of fluorescence representing the autoantibody-antigen complexes in the keratinocyte desmosomes.,Pemphigus Vulgaris,immunofluorescent staining of pemphigus autoantibodyies,weakening of desmosomes and loss of cell-to-cell adhesion.,Treatment,Prednisone is the drug of

7、 choice for control of this disease. Because of their steroid-sparing（类固醇治疗） effects, immuno-suppressive agents such as azathioprine, methotrexate, and cyclophosphamide are often included in difficult cases.,Benign Mucous Membrane Pemphigoid (Cicatrical Pemphigoid) 良性黏膜类天疱疮(瘢痕性类天疱疮),gingival pemphig

8、oid presenting as red patches and ulcers,gingival pemphigoid presenting as red patches and ulcers,symblepharon in mucous membrane pemphigoid,Benign Mucous Membrane Pemphigoid,Mucosa membrane pemphigoid is an autoimmune mucosal disease that infrequently affects the skin. Oral lesions are a source of

9、chronic discomfort, and ocular lesions are potentially very serious because of conjunctival inflammation(结膜炎） and scarring.,Etiology,How this disease is triggered is unknown. The antibodies that are produced are directed against basement membrane antigen, laminin 5, and so-called bullous pemphigoid

10、antigen 230.,Clinical Features,This is a disease of older adults (50 years) and especially women. Patients present with patchy ulcers preceded by blisters. Although any area of the mucosa may be affected, many patients have gingival disease. With chronicity, lesions may resemble lichen planus, and c

11、ontact hypersensitivity. The lesions are persistent, although patients will have periods of improvement. Pain assosciated with the ulcerations decreases in intensity with time. A positive Nikolsky sign may be seen.,Clinical Features,Conjunctival lesions may result in corneal damage in the form of sc

12、arring that can lead to blindness.Symblepharon is a complication of ocular pemphigoid. Less commonly, esions may be seen in the larynx, genitals, esophagus, and skin.,Histologic Features,Subepithelial separation is characteristic of this disease. The pathologic space appears through the basement mem

13、brane, leaving basal kertinocytes intact in the epithelial roof of the bulla. Direct immunofluorescence show linear deposits of IgG and C3 in the basement membrane zone.,subepithelial separation in mucosal pemphigoid,immunofluorescence-basement membrane stain,Treatment,Corticosteroids, can be used t

14、o help control this disease. The addition of steroid-sparing immunosuppressive drugs may be required when ocular pemphigoid is present.For patients with chronic gingival disease, excellent oral hygiene with chlorhexidine rinses(洗必泰） is of significant benefit in minimizing secondary inflammation.,Tre

15、atment,Some cases of gingival pemphigoid are refractory难治疗 to low or intermediate doses of prednisone. Effective control of many of these cases can be achieved through the use of high-potency(高效地）topical corticosteroids; high-dose prednisone is probably not warranted for this limited form of the dis

16、ease.,Epidermolysis Bullosa,ulcers and dystrophic nails in epidermolysis bullosa,Epidermolysis bullosa,This is a genetic term that includes several genetically derived bullous subtypes and one aquired subtype. Autoantibodies to type VII collegen are associated with the aquired type. No circulating a

17、ntibodies are seen in the hereditary 遗传 forms.,Epidermolysis bullosa,Large flaccid bullae are seen in areas of pressure in all forms of this condition. The severity of the disease is markedly greater in the recessive隐性遗传 forms. Nails and teeth may be dystrophic. Because of perioral scarring, construction of the oral orifice孔 is seen, making access for dental care