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T N Helm

Publications and source records attributed to T N Helm.

At least 37 records · Page 2Linked to original sources
PubMed1995

Ehlers-Danlos syndrome type IV: a single base substitution of the last nucleotide of exon 34 in COL3A1 leads to exon skipping.

The Ehlers-Danlos syndrome has been classified into nine phenotypic presentations. Type IV is a variant of particular importance because people affected with this genodermatosis are at great risk of spontaneous hemorrhage from vascular rupture or bowel perforation. Recent molecular advances have identified mutations in the gene for type III procollagen as responsible for Ehlers-Danlos syndrome type IV. We report a case of a 14-year-old male with a typical presentation of the type IV variant who was found to have markedly dilated fibroblast cisternae and varying collagen fibril diameter on ultrastructural study. A novel genetic defect was noted by polymerase chain reaction and DNA sequencing of genetic material isolated from skin fibroblast cultures. Analysis of the gene for type III procollagen revealed a single base mutation in the last nucleotide of exon 34. The mutation led to abnormal RNA splicing and skipping of exon 34 on the mRNA level.

Adolescent↗
PubMed1995

Generalized non-Langerhans cell histiocytosis: four cases illustrate a spectrum of disease.

BACKGROUND: The proliferation of non-Langerhans cell histiocytes is a poorly understood process of unknown cause. Variation in the clinical features and/or histopathology of histiocytic proliferation has led to subclassification of the general category of non-Langerhans cell histiocytes. Although the current classification may provide some useful generalizations in regard to the anticipated clinical course, wide variability in presentation and outcome make this classification less than optimal when dealing with individual patients. The objectives of the study were to present four cases of generalized non-Langerhans cell histiocytosis. MATERIALS AND METHODS: Medical records and slides of four patients diagnosed with non-Langerhans cell histiocytosis at the Cleveland Clinic are reviewed. RESULTS: The patients exhibit features of more than one subtype of non-Langerhans cell histiocytosis. CONCLUSION: The overlap among the clinical and histologic features of the generalized cutaneous non-Langerhans cell histiocytic disorders suggests that they represent one disease entity with a wide spectrum of presentations rather than many distinct disorders.

Adolescent↗
PubMed1994

Lichen planus associated with neoplasia: a cell-mediated immune response to tumor antigens?

BACKGROUND: Individual case reports have suggested an occasional association of lichen planus with internal malignancy. OBJECTIVE: Our purpose was to describe five patients with a neoplastic disease in whom lichen planus developed. METHODS: Serologic and immunopathologic studies were conducted. RESULTS: No evidence of autoantibody production characteristic of paraneoplastic pemphigus was found, and antibodies reactive with basal cell keratinocytes were not detected. CONCLUSION: Lichen planus may be rarely induced by neoplasia. A cell-mediated immune reaction possibly causes this phenomenon.

Adenocarcinoma↗
PubMed1994

Diffuse intraepidermal deposition of immunoreactants on direct immunofluorescence: a clue to the early diagnosis of epidermal necrolysis.

BACKGROUND: Toxic epidermal necrolysis is a distinctive disorder that is readily identified clinically and histologically in advanced cases. Early on, however, toxic epidermal necrolysis may be difficult to identify. Some consider fixed drug eruption a limited form of toxic epidermal necrolysis. METHODS: Direct immunofluorescence was performed on biopsy material of erythematous skin lesions. RESULTS: Diffuse deposition of immunoreactants in the midmalpighian layer was noted. This finding has not been encountered in other disorders studied in our immunopathology laboratory. CONCLUSIONS: Diffuse immunoreactant deposition in the mid-epidermis should suggest a diagnosis of epidermal necrolysis either from toxic epidermal necrolysis or fixed drug eruption. Additional cases will need to be assessed to document the usefulness of this pattern for prospective diagnosis.

Aged↗
PubMed1993

Pretibial mucin. Histologic patterns and clinical correlation.

BACKGROUND AND OBJECTIVE: We identified several patients with a histologic diagnosis of pretibial myxedema in whom thyroid disease was not found. The purpose of this study was to investigate if histologic characteristics can distinguish between pretibial mucinosis secondary to Graves' disease and that unassociated with thyroid disease. METHODS: Biopsy specimens interpreted as compatible with pretibial myxedema were reviewed; these included 12 cases of pretibial mucinosis with documented Graves' disease, and six cases of pretibial mucinosis without evidence of Graves' disease. Ten specimens interpreted as compatible with stasis dermatitis were also evaluated for histologic characteristics, including the possible presence of mucin. RESULTS: Features that distinguish between pretibial mucinosis associated with Graves' disease and pretibial mucinosis without Graves' disease included preservation of a zone of normal-appearing collagen in the superficial papillary dermis (12/12 with Graves' disease, 0/6 without), mucin deposition in the reticular dermis (12/12 with Graves' disease, 0/6 without), lack of mucin deposition in the superficial papillary dermis (11/12 with Graves' disease, 1/6 without), angioplasia (2/12 with Graves' disease, 6/6 without), and the presence of hemosiderin (2/12 with Graves' disease, 6/6 without). Mucin deposition in the papillary dermis was found in six of 10 specimens interpreted as stasis dermatitis. CONCLUSIONS: There are patients with pretibial mucinosis in whom there is no thyroid disease. Specimens from patients without Graves' disease have features of stasis dermatitis in addition to mucinosis. We conclude that pretibial mucinosis may result from stasis or Graves' disease and that histologic differences allow for accurate differentiation.

Diagnosis, Differential↗
PubMed1993

Paraneoplastic pemphigus. A distinct autoimmune vesiculobullous disorder associated with neoplasia.

A vesiculobullous disease termed paraneoplastic pemphigus with distinct autoantibodies was newly described in 1990. All reported cases have occurred in patients with a history of neoplasia, including lymphoma, chronic lymphocytic leukemia, poorly differentiated sarcoma, and benign thymoma. As in pemphigus vulgaris, intraepithelial clefts with acantholysis are noted histopathologically, and intercellular binding of immunoreactants is seen with direct immunofluorescence studies of mucous membrane and skin biopsies. However, immunoreactants may also be found along the basement membrane zone in paraneoplastic pemphigus. Indirect immunofluorescence using rat bladder epithelium as substrate shows an intercellular pattern that appears to be highly specific for paraneoplastic pemphigus. We report a patient with non-Hodgkins lymphoma of 8 years duration who developed severe erosive stomatitis and lichenoid dermatitis after receiving chemotherapy for a relapse of lymphoma. Her case illustrates the typical features of the disorder described as paraneoplastic pemphigus. Neoplasia-associated pemphigus may be a more precise term for this disorder because the course of the blistering eruption does not always parallel the course of the underlying cancer. The clinical features, histopathologic findings, and immunofluorescence findings of this unique syndrome are reviewed.

Aged↗
PubMed1993

Indirect immunofluorescence on rat bladder transitional epithelium: a test with high specificity for paraneoplastic pemphigus.

BACKGROUND: Paraneoplastic pemphigus is a blistering disease with specific serum immunoprecipitation findings. Although immunoprecipitation studies allow accurate diagnosis, they are time-consuming, expensive, and not readily available. In contrast, indirect immunofluorescence (IIF) testing of serum on transitional rat bladder epithelium is a simple and inexpensive method available to any immunopathology laboratory. OBJECTIVE: Our purpose was to determine the specificity of positive IIF on rat bladder epithelium for paraneoplastic pemphigus. METHODS: The IIF findings in four index cases of paraneoplastic pemphigus were compared with the findings in 47 patients with a variety of malignant neoplasms and no associated blistering disease as well as 49 patients with vesiculobullous or lichenoid disease but no neoplasia. RESULTS: IIF was negative in all patients with neoplasia and no blistering disease and negative in all but one of the patients with vesiculobullous or lichenoid disease without neoplasia (98.9% specificity). CONCLUSION: IIF on transitional rat bladder epithelium appears to be a highly specific test for paraneoplastic pemphigus. Because of its simplicity and inexpensiveness, we suggest that IIF be performed on transitional epithelium in any suspected case of paraneoplastic pemphigus.

Animals↗
PubMed1993

Vascular nodules and plaques resembling chronic mucocutaneous candidiasis in a patient with a low interleukin 2 level.

A 21-year-old woman had a lifelong history of widespread friable vascular nodules and plaques. Her condition had previously been diagnosed as chronic mucocutaneous candidiasis because of her clinical appearance. Routine studies of immune function were performed in addition to a comparison of cytokine secretion in mononuclear leukocytes of our patient and normal controls. Interleukin 2 secretion by phytohemagglutinin-stimulated mononuclear leukocytes was deficient when compared with six healthy donors (< 300 pg/ml vs 2108 +/- 336 pg/ml). Interleukin 2 deficiency may be a causative factor in cases of unusual vascular proliferation. Treatment with methotrexate, which increases interleukin 2 activity and inhibits neovascularization in vitro, was helpful in our patient.

Adult↗
PubMed1993

Ki-1-positive anaplastic large-cell lymphoma can mimic benign dermatoses.

BACKGROUND: Regressing atypical histiocytosis is a recently described disease characterized by recurrent nodules or ulcers. The cutaneous lesions appear abruptly and then regress only to return in a manner reminiscent of lymphomatoid papulosis. Immunophenotypic analysis has revealed that most cases are a form of anaplastic large-cell Ki-1-positive (CD30+) lymphoma. OBJECTIVE: We describe two patients with Ki-1-positive anaplastic large-cell lymphoma that had clinical and pathologic features of regressing atypical histiocytosis and mimicked benign dermatoses (pyoderma gangrenosum and morphea), causing a delay in confirming the true diagnosis. A third case that was readily recognized as a lymphoma is also presented. METHODS: The clinical and histopathologic findings were recorded. In addition, T-cell receptor gene rearrangement and immunophenotyping were determined in the index case. RESULTS: The index patient and second patient were diagnosed as having Ki-1-positive anaplastic large-cell lymphoma by immunophenotyping and underwent cyclophosphamide, doxorubicin, prednisone, and vincristine (CHOP) chemotherapy with complete remission. The patient detected by chart review died of her disease without receiving antineoplastic therapy; disseminated lymphoma was diagnosed at autopsy. Studies on paraffin-embedded tissue were consistent with Ki-1-positive anaplastic large-cell lymphoma. CONCLUSION: Regressing atypical histiocytosis may clinically resemble some benign dermatoses. Recent evaluation of these cases has shown that many represent a form of Ki-1-positive anaplastic large-cell lymphoma. Multiple skin biopsy specimens with immunophenotyping and gene rearrangement studies are required to arrive at the diagnosis.

Adult↗