The American Journal of dermatopathology
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Examination of 388 follicles in 24 large resections of skin for the presence of histologic folliculitis and Demodex mites uncovered a nonrandom association between these two phenomena. Demodex mites were found in 42% of follicles with inflammation, but in just 10% of the follicles without inflammation. ⋯ The probability that this result could occur by random chance alone was < 0.001, thus suggesting that Demodex is associated with histologic folliculitis, even minor folliculitis. The results do not, however, decide whether Demodex is causative, whether it preferentially selects follicles with histologic inflammation, or whether some of both processes operate.
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A simple and rapid procedure to diagnose major variants of congenital epidermolysis bullosa (EB) by means of immunohistochemical staining of collagen IV (CIV) in formalin-fixed and paraffin-embedded samples is described. Sixteen cases were stained with a monoclonal antibody (clone CIV 22) against collagen IV present in the lamina densa layer of the basement membrane. Electron microscopy was performed simultaneously. ⋯ In four cases, collagen IV staining was not reactive because of irreversible antigen loss due to inadequate fixation and/or embedding. In those cases with positive staining, an excellent correlation with electron microscopic diagnosis was achieved. This procedure allows a rapid diagnosis of major EB variants, especially where electron microscopy is not available, and also facilitates diagnosis by optimally orienting specimens for ultrastructural examination when available.
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Moth-eaten alopecia (MEA) is a characteristic manifestation of secondary syphilis. Clinically, this form of alopecia may be confused with trichotillomania, traction alopecia, and alopecia areata. ⋯ We systematically documented the histopathological features of 12 patients with MEA. Characteristic features included follicular plugging; a sparse, perivascular and perifollicular lymphocytic infiltrate; telogenization and follicle-oriented melanin clumping.
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Comparative Study
On the discriminatory value of anti-HPCA-1 (CD-34) in the differential diagnosis of benign and malignant cutaneous vascular proliferations.
The staining pattern of monoclonal antibody anti-HPCA-1 (CD-34) was studied in 95 cases of benign and malignant cutaneous vascular proliferations and compared with other vascular endothelium-associated antigenic markers in paraffin-embedded tissues. The proliferating vessels in 22 cutaneous capillary hemangiomas, 8 lobular capillary hemangiomas, and 1 case of papillary intravascular endothelial hyperplasia stained strongly positively for anti-HPCA-1, and the intensity of the reaction was paralleled by that of factor VIII-related antigen (FVIII), Ulex europaeus lectin-1 (UEA), and vimentin (VIM). ⋯ Nine cases of cutaneous angiosarcoma, two cases of low-grade epithelioid angiosarcoma, and one case of spindle-cell hemangioendothelioma were negative for anti-HPCA-1 and showed variable reactivity for FVIII and UEA; all cases stained strongly positively for VIM. The results of this study indicate that although anti-HPCA-1 shows a high sensitivity for the staining of normal vascular endothelium, its specificity may be restricted to mature, well-formed vessels, therefore rendering its discriminatory value very limited for the identification of poorly differentiated vascular endothelial neoplasms.