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

S6C10P4-1: This is a pattern that is distinctly different from classic forms of either pemphigus vulgaris, or pemphigus foliaceus. It is qualifies as a variant of pemphigus vegetans. There is marked epidermal hyperplasia with exaggerated rete patterns. The keratinocytes are hypertrophied and pale. There are intra-epidermal defects in the elongated columns of cells. The defects contain degenerating keratinocytes and inflammatory cells with a component of eosinophils. The papillary dermis is widened and edematous. Vessels are increased in number in the papillary dermis; they are ectatic.

S6C10P4-2: The intraepidermal defect is irregular in outline. It contains rounded, degenerating keratinocytes and an inflammatory infiltrate that is rich in eosinophils. The hypertrophic character of the pattern and the cytoplasmic qualities of keratinocytes, as seen in this field, are of a type commonly associated with an epidermis that is proliferating; the patterns might be characterized as providing evidence for a shift in kinetics to those favoring the expression of terminal differentiation (i.e., the features predominantly are those of a superficial unit that has committed to terminal differentiation). The pallor might be compared to that seen in the active phase of a keratoacanthoma (keratoacanthoma being an invasive neoplasm in which most of the invading epithelium expresses the phenotype of cells of the superficial unit of squamous epithelium). This is not actually pseudoepitheliomatous hyperplasia; the epithelium has not invaded the reticular dermis.

S6C10P4-3: In the area in which cells are sloughing into the defect, the keratinocytes show increased cytoplasmic density and acidophilia. Nuclei are more closely spaced (each cell has less cytoplasm). Some of the keratinocytes of  the clusters (those that are free in the lumen of the defect) are rounded in outline; some are individually isolated in the defect. The cytologic features qualify as acantholysis and dyskeratosis. Eosinophils are prominent in the inflammatory infiltrates. To the left, near the margin of the field, the interface between the superficial unit, and the basal unit is well defined.

S6C10P4-4: The change in patterns in this lesion of pemphigus take us into the realm of superficial acantholytic variants of pemphigus. The keratin layer is partially denuded along the surface. To the left, the epidermal patterns are psoriasiform. To the right, the basal unit hyperplasia is not as prominent; the rete patterns are partially effaced. Angulated, acidophilic keratinocytes produce jagged projections along the surface on the right; in this same area, the keratin layer has been lost. The cells, projecting irregularly along the surface, are keratinocytes in the process of losing their attachments to their neighbors. These projections are markers for a superficial process of acantholysis (superficial pemphigus, or pemphigus foliaceus). The acantholytic process extends along a dilated follicle into the region of the follicular infundibulum (blue arrows). The dermis shows some atrophy and telangiectasia. The atrophy may reflect the age of the patient, or may be secondary to treatment.

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.