摘要:

Sections from 22 formalin-fixed, paraffin-embedded skin biopsies from 12 patients with papulonecrotic tuberculid (PNT) were examined for the presence ofMycobacterium tuberculosisDNA with use of the polymerase chain reaction. All patients had a positive tuberculin skin test and a compatible clinical picture and responded to antituberculous therapy. Histological examination showed the typical morphology of PNT lesions with dermal necrosis surrounded by an ill-formed granulomatous infiltrate. Mycobacterial DNA was detected in 11 of the 22 biopsies. None of the negative controls showed positive DNA identification by amplification. Great care was taken in avoiding false-positive results due to contamination. After reviewing the literature, we believe this is the first time that PNT lesions have been investigated by PCR for the presence of mycobacterial DNA. These findings provide direct proof that mycobacterial products are present in PNT lesions and support the theory that this organism is in some way responsible for the development of PNT.

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Eight common nevi and 11 dysplastic nevi were evaluated for the presence of basic fibroblast growth factor, platelet-derived growth factor, transforming growth factor-α, interleukin-1-α, and interleukin-1-β by immunohistochemical labelling with highly specific monoclonal antibodies. Basic fibroblast growth factor was abundant in the nevus cells and keratinocytes of nevi. Dysplastic nevus cells on average stained less intensely for basic fibroblast growth factor than did common nevus cells. In both types of nevi, basic fibroblast growth factor was identified in the basement membranes at the dermoepidermal junction and surrounding nevus cell nests and individual nevus cells. Labelling of nevus cells for transforming growth factor-α was variable, while there was moderate labelling for platelet-derived growth factor and light labelling for interleukin-1-α. Only two nevi, both dysplastic, stained (very faintly) for interleukin-1-β. It is possible that these cytokines, especially basic fibroblast growth factor, act in autocrine fashion to maintain nevocellular growth and may also contribute to the epidermal hyperplasia and fibrosis frequently observed in nevi.

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

The primary hyperplastic nature of palisaded encapsulated neuromas (PENs) has been recently challenged by suggesting a traumatic origin. We studied eight cases of traumatic neuroma (TN) and 12 cases of PEN by routine light-microscopic, histochemical, and immunohistochemical methods to assess evidence of previous tissue injury. Sections from the formalin-fixed, paraffin-embedded tissue were stained with hematoxylin-eosin, trichrome, elastic, reticulin, Giemsa, colloidal iron (with and without hyaluronidase), and Bielschowsky silver stains. Antibodies were applied to collagen types I, III, and IV. MAC 387, factor XIIIa, α1,-antitrypsin (AIAT), epithelial membrane antigen (EMA), Leu-7, and myelin basic protein using ABC techniques. We found that (a) in TN the individual fascicles were usually surrounded by perineurial cells, whereas in PEN the perineurial cells were observed mainly in the capsular areas and only rarely within the fascicles as evidenced by EMA antibodies; (b) histochemically TN contained considerably larger amounts of collagen (types I and III), acidic mucin, and myelin products than did PEN; and (c) neither PEN nor TN contained increased inflammatory cells or cells positive for factor XIIIa, MAC 387. or AIAT. We conclude that (a) there are substantial structural and histochemical differences between TN and PEN, (b) the changes suggest that the classic form of PEN has a different histogenesis than TN, and (c) on histologic grounds, chronic minor trauma could not be excluded as an etiologic factor for PEN.

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

The clinical, histological, immunophenotypic, and genotypic characteristics of two cases of cutaneous genuine histiocytic lymphoma are described. Both cases presented as cutaneous lesions. Both patients remain alive and free of disease at 26 and 10 months after the diagnosis and after having been treated with polychemotherapy. Neither peripheral blood nor bone marrow infiltration was detected in either case. Histological and immunophenotypic examination showed dense, diffuse dermic infiltrates of mononuclear cells with positive macrophage-associated markers (CD11c, CD68), and negative T- or B-cell-associated antigens. A germline configuration of both T-cell receptor and immunoglobulin genes was observed in gene rearrangement studies. Although most of the cases that have been diagnosed as histiocytic lymphoma or malignant histiocytosis in the past turned out to be B- or T-large-cell lymphomas, a small number of cases (two in our consecutive series of 350 cases) show characteristics of monocyte-macrophage tumors. We stress the importance of the CD68 marker in the diagnosis of true histiocytic lymphoma, suggest a therapeutic approach based on similarities with monocytic leukemia, and propose the use of the termmonocytic sarcomafor this clinicopathological presentation.

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Authors of most textbooks of dermatology and dermatopathology consider guttate parapsoriasis and digitate dermatosis to be variants of small plaque parapsoriasis which, they aver, is not related to mycosis fungoides. On the basis of a study of clinical and histopathologic findings in guttate parapsoriasis and digitate dermatosis. we conclude that those conditions actually represent two of the many clinical faces of mycosis fungoides.

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

A fibroblastic skin tumor with a myxoid matrix is reported that cannot be easily classified as one of the well-known entities of fibrous/fibrohistiocytic and myxoid skin tumors. A 27-year-old white woman presented with a reddish, dome-shaped cutaneous nodule 8 mm in diameter on the left popliteal fossa that had developed spontaneously within the preceding 2 years. There was no sign of recurrence 30 months after excision. Light microscopic examination showed a well-circumscribed tumor confined to the upper dermis and consisting of stellate and spindle-shaped cells arranged loosely in a fascicular pattern resembling tissue cultures of fibroblasts. There were almost no collagen bundles between tumor cells, and Mowry's staining showed large amounts of glycosaminoglycans. Immunohistochemical studies of the tumor cells showed reactivity only to vimentin, whereas markers of histiocytes, dermal dendrocytes, and neurogenic and myogenic differentiation were negative. By electron microscopy, the majority of tumor cells contained elliptical nuclei, but some tumor cells had conspicuous multisegmented nuclei with several large and small nuclear segments connected by thin nuclear bridges (labyrinth nuclei). Single fibrils were found within the interstitium; collagen fibers were rare. Histological and ultrastructural examinations identified tumor cells as fibroblasts. High cellularity distinguishes this tumor from cutaneous myxoma. We conclude that this lesion represents a newly recognized tumor of fibroblastic origin. The name cutaneous myxoid fibroblastoma is proposed.

ISSN:0193-1091    

出版商:OVID    

年代:1992

数据来源: OVID