S6C21P15CPemphigoid

Buttons below provide access to pictorials and to respective PARENT CHAPTERS.


	S6C21P15-1: Condensed fibrin is prominent along the surface of the floor of the bulla. The fibrin covers distorted papillae. It contains loose infiltrates of histiocytes and neutrophils. Connective tissue of the altered papillary dermis is activated (increased number of fibroblasts per unit area and enlargement of fibroblasts and their nuclei). Smudgy basophilic deposits at the extremities of blue arrows are representative of the sites in which neutrophils have undergone lysis and nucleic acids have impregnated the fibrin. The neutrophils and histiocytes disintegrate, but the enzymes fail to digest the fibrin. In cicatricial pemphigoid, there is perhaps a deficiency in the formation, and release, of the enzymes required for the digestion of the fibrin. On the other hand, damage to basement membrane and activation of connective tissue cells must also be considered in accounting for the organization of condensed fibrin.

	S6C21P15-2 (cicatricial pemphigoid): The margin of the bulla is represented to the left. The bulla does not appear to be tense (the angle at the margin is narrow). Inflammatory cells, including histiocytes and neutrophils, have collected in the papillary dermis near the basement membrane zone. In this example, there is no evidence of significant papillary dermal fibrosis; the lesion is young.

S6C21P15-3 (cicatricial pemphigoid): At the margin of a bulla, neutrophils and histiocytes form loose, linear arrays near the basement membrane zone.The blue arrows represent an attempt to define the basement membrane zone but, in areas, definition is difficult.

	S6C21P15-4: In this example of discoid lupus erythematosus of the scalp, the epidermis is attached to the dermis; the basic patterns are lichenoid. The epidermis has the features of a hyperplastic superficial unit with a deficient basal unit. The basal layer shows liquefaction degeneration. There is slight thickening and hyalinization of the basement membrane. Focally, lymphoid infiltrates are band-like at the dermal-epidermal interface; they hug the epidermis. The papillary dermis is widened and fibrotic. A follicle to the left is ectatic; it contains a keratotic plug. Lesions of lupus erythematous must be considered in the differential diagnosis of cicatricial pemphigoid.

S6C21P15-5: Although the papillary dermis is relatively free of inflammatory cells, the fibrotic papillary dermis is a marker providing evidence of chronicity. Lesions of cicatricial pemphigoid become chronic and “fixed.”

S6C21P15-6: The red arrows are distributed in a manner to define the basement membrane zone. Above this area, a defect contains condensed fibrin with an infiltrate of histiocytes and neutrophils. There are fragments of nuclear debris in the fibrin. Fibroblasts are increased in number near the basement membrane zone. Some appear to have extended beyond the basement membrane zone into the fibrin. The blue arrows identify pale zones of the altered papillary dermis that are relatively devoid of connective tissue fibers. While this pallor of the papillary dermis may be evidence of edema, I would favor the interpretation that the zones of pallor are markers for stromolysis, or fibrolysis, of connective tissue. The changes would suggest that, in a lesion showing a pattern of this type, there would be an abundance of digestive enzymes. The apparent failure of enzymes to digest the condensed fibrin, suggests that either the region is actually deficient in the enzymes which are required for the lysis of fibrin, or the fibrin is abnormally resistant.

CLICK TO GO TO NEXT PAGE IN SEQUENCE

SELECTED READING

BACK (spatial sequence)

CLICK TO GO UP ONE PAGE (to return to parent textual page, if at LEVEL 3, or the return to HOME, if at LEVEL 2)

Green buttons provide access to two web sites, and mauve buttons to all of the SECTIONS of this SITE.

First two items to the right provide access to web sites