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Biomedical subjects

S Kossard

Publications and source records attributed to S Kossard.

At least 55 records · Page 3Linked to original sources
PubMed1996

Pathological twists in association with infectious agents and infestations of the skin.

The capacity of micro-organisms and infestations to induce flare or mimic a wide variety of dermatological disorders has long been appreciated. The development of new techniques such as in situ hybridization and the polymerase chain reaction has permitted a re-examination of old concepts such as the tuberculids and bacterids. In addition new discoveries have highlighted the biological potential of micro-organisms to stimulate or depress the immune system through potent biological active products and has led to new insights in the mechanisms through which organisms may produce skin changes. Histological simulants of dermatological disease may also be induced by micro-organisms and these may need to be distinguished by clinical correlation.

Bacterial Infections↗
PubMed1995

Merkel cell carcinoma with a desmoplastic portion.

Merkel cell carcinoma of the skin usually has a trabecular, intermediate-cell or small-cell pattern of differentiation. We report the case of a 66-year-old man who developed a progressive multinodular plaque that showed a prominent desmoplastic component on preliminary biopsy. Immunohistochemical and ultrastructural studies and the final surgical specimen confirmed that the tumor was a Merkel cell carcinoma. The presence of desmoplasia may mask the diagnosis of Merkel cell carcinoma.

Aged↗
PubMed1995

Quantification of hair follicle parameters using computer image analysis: a comparison of androgenetic alopecia with normal scalp biopsies.

Computer image analysis enables large numbers of hairs to be measured in an automated fashion. In this study, we examined horizontal scalp biopsies from 10 patients with a histological diagnosis of androgenetic alopecia and 10 normal control subjects. The density of hair follicles and the ratio of terminal to vellus hairs were determined. Hair shaft, hair canal and hair follicle diameter, inner root sheath width and outer root sheath area were measured using the Chromatic Colour Image Analysis program. This study showed a statistically significant progressive decrease in size of hair canal diameters from normal terminal hairs (85.93 +/- 10.07 microns) through to androgenetic alopecia terminal (68.83 +/- 13.60 microns) and vellus hairs (28.67 +/- 5.60 microns). This pattern is also seen with hair follicle diameters; normal terminal (268.41 +/- 24.88 microns), androgenetic alopecia terminal (236.34 +/- 17.23 microns), and vellus hairs (130.88 +/- 19.96 microns). Outer root sheath areas, hair shaft diameters and ratio of terminal to vellus hairs were significantly larger in normal (18,500 +/- 4222 microns 2; 82.71 +/- 13.79 microns; 36:1; respectively) compared with androgenetic alopecia scalp biopsies (8403 +/- 3322 microns 2; 61.11 +/- 14.42 microns; 3:1; respectively), whereas inner root sheath width and density did not vary significantly. Computer image analysis can be adapted for use in clinical trials where large numbers and objectivity are critical in determining the efficacy of hair growth promoters.

Adult↗
PubMed1995

Paraneoplastic pemphigus triggered by radiotherapy.

Paraneoplastic pemphigus is a recently described autoimmune disease characterized by painful mucosal ulceration and polymorphous skin lesions in association with an underlying neoplasm. Distinct autoantibodies bind desmoplakin I, desmoplakin II, bullous pemphigoid antigen and an uncharacterized 190 kDa antigen. A case is presented of paraneoplastic pemphigus that developed after radiotherapy for non-Hodgkin's lymphoma in a 53 year old man. Multiple skin biopsies showed a lichenoid reaction without acantholysis. Immunofluorescence and mucosal biopsies were required to establish the correct diagnosis. Corneal opacities resembling lichenoid graft-versus-host disease and retinal haemorrhages, which developed in the patient, have not been previously documented. Despite high doses of immunosuppressive agents and plasmaphoresis, the patient eventually died from respiratory failure.

Acantholysis↗
PubMed1995

Basaloid folliculolymphoid hyperplasia with alopecia as an expression of mycosis fungoides (CTCL).

Follicular mucinosis, papules, cysts and comedones have been previously described as expressions of follicular involvement by mycosis fungoides. We report a patient with mycosis fungoides who developed extensive alopecia. Multiple scalp biopsies showed perifollicular and intrafollicular infiltrate of lymphocytes but no evident follicular mucinosis. On transverse sections many of the follicles showed an absence of differentiation towards hair sheath, canal, sebaceous gland or hair formation, but instead formed undifferentiated basaloid structures. These basaloid structures showed transition from atrophic telogen follicles to hypertrophic basaloid islands infiltrated by lymphocytes, resembling the pattern previously described in cutaneous lymphadenoma. Immunophenotyping showed a predominance of helper T-cells which, on ultrastructural examination, showed cerebriform nuclei. The unusual histological findings in our case may be analogous to the hyperplasia seen in sweat glands in syringotropic mycosis fungoides (syringolymphoid hyperplasia), and we propose the term basaloid folliculolymphoid hyperplasia to describe this feature. Basaloid follicular hyperplasia has been previously described as a component of follicular mucinosis but may apparently develop in the absence of overt mucinosis.

Aged↗
PubMed1995

Nucleolar organizer regions and image analysis nuclear morphometry of small cell (nevoid) melanoma.

Small cell (nevoid) melanomas may provide difficulties in diagnosis as their constituent cell type resembles a benign nevoid melanocyte. In the present study, 10 small cell melanomas were analyzed for the silver staining of their nucleolar organizing regions (AgNORs), and their nuclear area and perimeter were measured by computerized digital image analysis and compared with 10 superficial spreading melanomas lacking small cell differentiation and 10 dermal nevi. The average number of AgNORs per nucleus was 5.83 (SD +/- 1.69) for small cell melanomas and was significantly different when compared with 8.49 (SD +/- 1.58) for superficial spreading melanomas (p < 0.05) and 2.71 (SD +/- 0.50) for dermal nevi (p < 0.05). Digital image analysis confirmed that the nuclear perimeter and nuclear area of cells in nevoid melanomas did not significantly differ from those of ordinary dermal nevi (p > 0.05), but both group were significantly different from superficial spreading melanomas lacking a small cell morphology (p < 0.05). Counting AgNOR numbers may be useful in evaluating small cell (nevoid) melanomas and provides a technique for differentiating their constituent cell from ordinary nevus cells. Nuclear morphometry determined by digital image analysis may help better define the nuclear size in small cell melanomas.

Adolescent↗
PubMed1994

Postmenopausal frontal fibrosing alopecia. Scarring alopecia in a pattern distribution.

BACKGROUND: Recession of the frontal hairline is a common event in postmenopausal women. This has been shown not to be a marker of gross androgenization, and is usually a progressive nonscarring alopecia. Six postmenopausal women, who developed a progressive frontal scarring alopecia, were studied and their clinical and laboratory data, as well as the results of scalp biopsy specimens in all six patients, were analyzed and compared with recognized forms of scarring alopecia and recently described findings in androgenetic alopecia. OBSERVATIONS: The six postmenopausal women developed a progressive frontal hairline recession that was associated with perifollicular erythema within the marginal hairline, producing a frontal fibrosing alopecia extending to the temporal and parietal hair margins. Scalp biopsy specimens from the frontal hair margin showed perifollicular fibrosis and lymphocytic inflammation concentrated around the isthmus and infundibular areas of the follicles. Immunophenotyping of the lymphocytes showed a dominance of activated T-helper cells. Clinical review of all six cases showed a progressive marginal alopecia without the typical multifocal areas of involvement seen in lichen planopilaris or pseudopelade. None of the patients had mucous membrane or skin lesions typical of lichen planus. Hormonal studies, in five patients, showed no elevated androgen abnormalities. CONCLUSIONS: Progressive frontal recession in postmenopausal women may show clinical features of a fibrosing alopecia. The histologic findings are indistinguishable from those seen in lichen planopilaris. However, the absence of associated lesions of lichen planus in all six women raises the possibility that this mode of follicular destruction represents a reaction pattern triggered by the events underlying postmenopausal frontal hairline recession.

Aged↗
PubMed1993

Spotted cicatricial alopecia in dark skin. A dermoscopic clue to fibrous tracts.

Study of areas of cicatricial alopecia in a 42 year old black woman by dermoscopy with oil revealed uniform pale dots associated with a radiating pigment network. Scalp biopsy showed a cicatricial alopecia with lichen planopilaris and multiple fibrous tracts. The pale dots appear to correspond to focal decrease in epidermal melanin pigment overlying the site of the fibrous tracts and may provide a dermoscopic clue in analysing the cicatricial alopecias.

Adult↗
PubMed1993

Histological evaluation of the effect of 0.05% tretinoin in the treatment of photo damaged skin. Geographic differences in elastosis in baseline biopsies.

In a randomised double-blind vehicle controlled trial of 0.05% tretinoin cream in the treatment of photodamaged skin, the histological results of paired biopsies from 28 individuals who applied tretinoin for 26 weeks are compared with 28 paired biopsies from a control group applying vehicle alone. There was a significant increase in epidermal thickness in the tretinoin-treated group (P < .001). Epidermal atrophy was reversed in ten patients applying tretinoin cream. Baseline biopsies obtained from participants in Melbourne, Victoria (38 degrees latitude) showed significantly less elastosis than those in Sydney (34 degrees latitude) and Newcastle in N.S.W., although the two groups did not show significant differences in age or sex, and the differences could not be correlated with skin type. Tretinoin cream had no effect on the degree of solar elastosis after 26 weeks application. Tretinoin cream appears effective in reversing epidermal atrophy and clinically diminishes fine wrinkling, mottled hyperpigmentation and skin roughness. Tretinoin cream may not offer a solution to the gross solar damage seen in the Australian population who have marked solar elastosis as a principal, clinical and histologic finding. However it is possible that dermal repair and reversal of solar elastosis may require topical application of tretinoin cream for a longer period than the six months used in this trial.

Administration, Topical↗
PubMed1992

Cutaneous Bowen's disease. An analysis of 1001 cases according to age, sex, and site.

BACKGROUND: There are no large studies of Bowen's disease that have analyzed its distribution according to age, sex, and site. OBJECTIVE: This study was performed primarily to determine whether there were significant sex and site differences in the distribution of Bowen's disease. METHODS: One thousand one skin biopsy specimens of Bowen's disease were analyzed according to age, sex, and site of origin. RESULTS: This study revealed that the most common site of Bowen's disease was the head and neck (440 lesions), whereas specimens from the lower limbs (298 lesions) and upper limbs (198 lesions) outnumbered specimens from the torso (65 lesions). Of 298 specimens from the lower limbs, 72.1% were from women; 79.3% of the 87 specimens from the scalp and ears were from men. Eighty percent of the 85 specimens of Bowen's disease from the cheeks were from women. CONCLUSION: These results indicate that cutaneous Bowen's disease occurs mainly on sun-exposed sites. This is also supported by the predominance of Bowen's disease on the lower limbs in women and on the scalp and ears in men. The basis for the female predominance on the cheeks is unknown, but may reflect the increased vulnerability to sun damage of superficial vellus hair follicles that predominate on the cheeks in women. This finding may provide indirect support for the hypothesis that some forms of Bowen's disease have a follicular histogenesis.

Adult↗
PubMed1992

Mast cell quantitation by image analysis in adult mastocytosis and inflammatory skin disorders.

Mast cell numbers were quantitated in adult cases of mastocytosis demonstrating non-diffuse perivascular and upper dermal concentrations of mast cells. Using the Leder stain and computerised video image analysis, a mean of 382 (+/- 28 SE) mast cell per mm2 were counted in the superficial dermis in skin biopsies from 30 adult cases of mastocytosis, in contrast to a mean of 43 (+/- 5 SE) mast cells per mm2 in skin biopsies from 50 inflammatory dermatoses represented by subacute dermatitis, pigmented purpuric dermatosis, erythema multiforme, lichen planus and granuloma annulare. Ten skin biopsies showing no significant inflammation had a mean of 54 (+/- 7 SE) mast cells per mm2 in the upper dermis. The mean area of individual mast cells as assessed by image analysis in the mastocytosis group was 47.40 microns 2 (+/- 2.26 microns 2, SE) which was significantly different (P < 0.01) than the mast cell area (32.34 microns 2 +/- 2.22 microns 2, SE) in all other groups combined. Computerised video image analysis represents an alternative technique which is useful in assessing mast cell numbers and particularly mast cell size in adult cases of macular mastocytosis and in other dermatoses.

Adult↗