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Biomedical subjects

A H Mehregan

Publications and source records attributed to A H Mehregan.

At least 19 recordsLinked to original sources
PubMed2000

Cutaneous malakoplakia: a report of two cases with the use of anti-BCG for the detection for micro-organisms.

Malakoplakia is an uncommon granulomatous infectious disease that is found primarily in the genito-urinary tract, but may rarely involve the skin. Histologic findings are marked by the presence of foamy macrophages containing basophilic concentric spherules, the Michaelis-Gutman bodies. Micro-organisms are not readily identifiable. Immunostaining with polyclonal anti-mycobacterium bovis (BCG) has been described as a method of identifying bacterial and fungal organisms in situations where organisms may be sparse. We report 2 cases of cutaneous malakoplakia with demonstration of organisms by immunostaining with anti-BCG antibodies.

Aged↗
PubMed1998

Staining of eccrine and apocrine neoplasms and metastatic adenocarcinoma with IKH-4, a monoclonal antibody specific for the eccrine gland.

The histogenesis of apocrine and eccrine neoplasms has always interested dermatopathologists. In addition, the histologic differential diagnosis of eccrine carcinoma from metastatic adenocarcinoma is of practical importance. We describe a novel monoclonal antibody IKH-4 which stains the eccrine secretory coil, but not the apocrine secretory segment. Positive staining was observed in eccrine hidradenoma, eccrine poroma, eccrine spiradenoma, papillary eccrine adenoma, eccrine hidrocystoma, syringoma, eccrine carcinoma, and in 1 case of syringocystadenoma papilliferum. Negative staining was observed in apocrine adenocarcinoma, hidradenoma papilliferum, erosive adenomatosis of the nipple, and primary and metastatic adenocarcinomas. IKH-4 antibody was useful in differentiating eccrine from apocrine neoplasms and in differentiating eccrine carcinoma from metastatic adenocarcinomas.

Adenocarcinoma↗
PubMed1997

Detection of Borrelia burgdorferi DNA (B garinii or B afzelii) in morphea and lichen sclerosus et atrophicus tissues of German and Japanese but not of US patients.

OBJECTIVE: To elucidate the geographic and genospecific association of Borrelia with morphea and lichen sclerosus et atrophicus (LSA). DESIGN: The association of Borrelia burgdorferi with morphea and LSA has been reported, but is still controversial. We conducted a retrospective survey of Borrelia DNA in skin biopsy specimens. SETTINGS: The samples were collected from the outpatient clinic of university hospitals and a dermatopathology laboratory. PATIENTS: Skin biopsy specimens (19 morphea and 34 LSA) were obtained from patients in the United States, Japan, and Germany. DNA samples were subjected to amplification with polymerase chain reaction for B burgdorferi flagellin gene, and for the genotype-specific detection of B burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii. RESULTS: Five cases of morphea and 2 cases of LSA in Germany and Japan yielded positive signals for B garinii or B afzelii, the European species. None of the American samples were positive for Borrelia polymerase chain reaction. Borrelia burgdorferi sensu stricto was not detected in any of the specimens. CONCLUSION: Morphea and LSA in Germany and Japan can be related with European genotypes of Borrelia.

Adolescent↗
PubMed1996

Amelanotic lentigo maligna melanoma: a diagnostic conundrum-- presentation of four new cases.

BACKGROUND: The clinical appearance of amelanotic lentigo maligna melanoma (ALMM) is quite confusing and usually is not diagnosed prior to histopathologic examination. METHODS: We have studied four new patients with ALMM whose correct diagnosis was not obtained from any one clinical finding. We arrived at the final diagnosis in an unexpected way, having had biopsied the lesions for diagnoses other than malignant melanoma. RESULTS: ALMM presents as a nonspecific skin lesion with no single indicative characteristic. A search of the literature confirmed our difficulty in making the diagnosis. CONCLUSIONS: To diagnose ALMM, one has to be cognizant of this condition and has to consider a constellation of findings that are unusual with melanocytic lesions. Questionable lesions must be biopsied for definitive histopathologic diagnosis.

Aged↗
PubMed1996

Chronic lupoid leishmaniasis. Evaluation by polymerase chain reaction.

BACKGROUND: The cutaneous lesions in chronic lupoid leishmaniasis resemble those of lupus vulgaris, both clinically and histologically. The differential diagnosis is difficult and may depend on the detection of a few Leishmania amastigotes in the histologic sections, the growth of the promastigotes in cultures, or the identification of amastigotes by other techniques. Polymerase chain reaction was used to detect Leishmania amastigote DNA in tissue samples obtained from 65 patients with chronic lupoid leismaniasis, and the results were confirmed by Southern blot analysis. OBSERVATIONS: The histologic findings of a predominantly epithelioid cell granuloma surrounded by lymphocytic infiltrate in chronic lupoid leishmaniasis are very similar to those observed in lupus vulgaris. Extensive histologic examination of the sections in this series revealed occasional macrophages containing a few amastigotes in only 12 cases. Cultures in NNN medium yielded Leishmania promastigotes in 20 cases. Polymerase chain reaction studies using a Leishmania-specific primer identified Leishmania DNA in 30 of 63 cases, and those using a Mycobacterium tuberculosis primer were found to be negative for mycobacteria in 47 cases tested, including 11 cases with a positive tuberculin skin reaction. CONCLUSIONS: The histologic findings in chronic lupoid leishmaniasis resemble those of lupus vulgaris. Polymerase chain reaction studies were useful in identifying amastigotes in 30 (47.6%) of 63 cases. This study confirms the presence of DNA molecules of Leishmania amastigotes in samples of formalin-fixed, paraffin-embedded granulomatous tissue obtained from patients with chronic lupoid leishmaniasis.

Adolescent↗
PubMed1995

Spindle cell lipomas. A report of two cases: one with multiple lesions.

BACKGROUND: Spindle cell lipoma is an unusual and histologically distinctive form of lipoma occurring primarily in older individuals. OBJECTIVE: The dermatologic surgeon and pathologist should be familiar with this variant of lipoma. METHODS: We are reporting two cases of spindle cell lipomas with the results of histologic examination with special stains and immunohistochemical studies. RESULTS: The neoplasms consisted of lobulated masses of mature adipose tissue with areas of spindle cell proliferation. There was strong positive staining with antibodies for vimentin within the areas of spindle cells proliferation. One of the cases is unusual in that multiple lesions are occurring in a young patient. CONCLUSION: Recognition of the histologic pattern is important in distinguishing the benign spindle cell lipoma from the malignant liposarcoma.

Adipose Tissue↗
PubMed1994

Basal cell epithelioma arising from epidermoid cyst.

BACKGROUND: Basal cell epithelioma is a tumor arising from a pluripotential cell found within the basal cell layer of the epidermis or various appendageal structures. OBJECTIVE: We report two cases of basal cell epithelioma arising from the wall of an epidermoid cyst. METHODS AND RESULTS: Review of our files produced two cases of basal cell epithelioma arising from a cyst wall. CONCLUSION: Basal cell epithelioma arising from the wall of an epidermoid cyst is rare. Examination of all cysts removed surgically is important as not to overlook this possibility and to allow close follow-up for potential recurrence.

Adult↗
PubMed1993

Malignant melanoma in childhood.

Six cases of malignant melanoma in children 14 years of age and younger are reported. The six cases were diagnosed among 850,000 consecutive skin biopsy specimens and consultation slides examined within a 32-year period. This series included an infant born with neurocutaneous melanosis, a child with malignant melanoma developing in a large congenital nevus at the age of 13 years, a superficial spreading malignant melanoma, Clark Level III, in a child with many dysplastic nevi, and three cases with primary nodular malignant melanoma, two of which showed histologic features of Spitz nevus. A review of the literature indicates that malignant melanoma in childhood is rare, and no large series have been investigated. It is not known whether the genetic and the environmental factors incriminated in the development of malignant melanoma in adults play a role in childhood melanomas. Data on the incidence of childhood melanoma in the population, the clinical and the histologic variations, and the prognosis are not adequate. A multiinstitutional study is needed to gather a large enough series to provide this information.

Adolescent↗
PubMed1993

Ultrastructural study of vitiligo.

BACKGROUND: Vitiligo is a relatively common skin disease characterised by development of patchy depigmented macules. A comparative ultrastructural study was undertaken between early developing (2-6 months duration) and long standing (1-5 years duration) lesions of vitiligo in a series of ten patients. METHODS: Skin biopsy specimens from the ten patients were fixed, stained, and examined under an electron microscope. RESULTS: No melanocytes were found in the sections taken from long standing lesions. The sections from early lesions showed junctional melanocytes exhibiting various cellular abnormalities. The epidermal keratinocytes were normal in all sections; however, some sections from the periphery of early lesions exhibited minor degenerative changes. CONCLUSIONS: We can assume that because of the absence of melanocytes in long standing lesions, repigmentation may occur only from the melanocytic reservoir in the hair follicles. Repigmentation may also occur in lesions of short duration by reactivation of melanocytes present in the area, so an attempt should be made to treat vitiligo lesions in their early stage.

Adult↗
PubMed1993

Pilary complex carcinoma: an adnexal carcinoma of the skin with differentiation towards the components of the pilary complex.

We report twelve cases with a distinctive form of adnexal carcinoma occurring most commonly over the head and neck of relatively old individuals. The growth was single in all cases, deep dermal in location, and consisted of massive proliferation of small basaloid cells with only occasional connection with the surface epidermis. The basaloid tumor masses showed only a few areas of palisading of their outer cell nuclei and occasional retraction space formation. The neoplasm revealed scattered areas of trichilemmal and epidermoid keratinization, foci of sebaceous, and areas of sweat ductal differentiation indicating participation of various components of the pilary complex.

Adult↗
PubMed1993

Deep penetrating nevus.

BACKGROUND: Deep penetrating nevus is a variant of melanocytic nevi with histologic features that may be alarming and can be mistaken for malignant melanoma. We are presenting a review of the clinical findings and the histologic features of deep penetrating nevus in a series of 14 cases. OBSERVATIONS: Deep penetrating nevus occurs most commonly over the acral skin of young adults. Clinically, the lesions were diagnosed as pigmented nevus, blue nevus, or malignant melanoma. Histologically, deep penetrating nevus shows a wedge-shaped lesion extending to the deep dermis and the subcutaneous fat tissue. Nests and fascicles of pigmented melanocytes extended deep at the periphery of blood vessels, nerves, and the cutaneous adnexa. Low-grade cellular atypia is present and mitoses are rare. CONCLUSIONS: Deep penetrating nevus is a variant of benign pigmented nevi with deep dermal and subcutaneous involvement. The pattern should be recognized and differentiated from malignant melanoma.

Adolescent↗
PubMed1992

Angiomyolipoma.

Angiomyolipoma is a benign tumor, usually of the kidney, that is frequently associated with tuberous sclerosis. Extrarenal tumors are rare. Cutaneous lesions have only recently been reported. We report a case of cutaneous angiomyolipoma with results of clinical, histologic, and immunohistochemical evaluation.

Hemangioma↗
PubMed1992

Malignant blue nevus: a report of eight cases.

Malignant blue nevus is uncommon compared to its benign counterpart and is regarded as a rare form of malignant melanoma. We report the clinical and histological findings in eight cases. Histologically, all eight specimens showed no epidermal involvement and had contained within or were adjacent to portions of blue nevus or cellular blue nevus. Proliferation of bundles of bipolar spindle shaped cells with marked cellular atypia, mitotic figures, foci of necrosis, and inflammatory cell infiltrate were noted. Two of the cases were studied by DNA flow cytometry and the populations of tumor cells were found to be diploid. Two cases have died secondary to metastasis. Although malignant blue nevi may not behave as aggressively as nodular malignant melanoma, they have definite potential to do so and therefore should be removed by wide surgical excision.

Adolescent↗