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Biomedical subjects

F Potet

Publications and source records attributed to F Potet.

At least 127 records · Page 7Linked to original sources

[Diagnostic quality control of hepatobiliary echography by autopsy correlation].

A methodology to evaluate routine ultrasonography performed in liver pathology is described. The results of 62 autopsies, undoubtedly the most accurate anatomical reference, were compared to those of sonographic examination of the liver performed two months before death at the most. Discordance was found in 23 cases. False negative results in the detection of metastasis and thrombosis of hepatic veins or inferior vena cava were the major pitfalls. The reasons and the consequences of each error were determined for each case.

Autopsy↗

Lymphoid follicular proctitis. A condition different from ulcerative proctitis?

A heterogeneous group is formed by patients presenting with clinical features suggestive of inflammatory bowel disease limited to the rectum and whose rectal biopsies show lymphoid follicular hyperplasia of the mucosa. All these cases are traditionally considered as one variant of chronic ulcerative colitis, so-called ulcerative proctitis. Twenty such cases were critically assessed on clinical, endoscopic, and histologic grounds, as well as on response to treatment and follow-up data. While 11 patients showed clinicopathologic features consistent with typical chronic ulcerative colitis, the other nine patients appeared to form a different group, for which the term "lymphoid follicular proctitis" seemed justified. Lymphoid follicular proctitis was, overall, characterized by rectal bleeding, a congested and granular mucosa without ulceration, abnormal and coalescing hyperplastic lymphoid follicles without acute inflammation, and failure to respond to local steroid therapy. The nature of lymphoid follicular proctitis is uncertain at present but seems unrelated to chronic ulcerative colitis.

Adolescent↗

Liver phospholipidosis induced by parenteral nutrition: histologic, histochemical, and ultrastructural investigations.

Histochemical and electron microscopic examinations of the liver were performed in 5 adults receiving parenteral nutrition for greater than 18 mo and in 4 adults receiving parenteral nutrition for less than 5 mo. Phospholipidosis, reflected by the presence of cytoplasmic phospholipid deposits at histochemical examination and the presence of multilamellar lysosomes at electron microscopy, was marked and present in hepatocytes, Kupffer cells, and portal macrophages in all 5 patients receiving parenteral nutrition for greater than 18 mo. Mild phospholipidosis, affecting only hepatocytes, was demonstrated in 3 of the 4 patients receiving parenteral nutrition for less than 5 mo. These findings indicate that liver phospholipidosis is relatively common in patients receiving parenteral nutrition and that the degree of liver phospholipidosis depends on the duration of parenteral nutrition. Liver phospholipidosis might be due to intrahepatic accumulation of intravenous phospholipids provided by fat-emulsion sources.

Adult↗

Same peculiar subset of HML1 + lymphocytes present within normal intestinal epithelium is associated with tumoral epithelium of gastrointestinal carcinomas.

The present study shows that the distribution of T lymphocytes in gastrointestinal carcinomas and their metastases mimic the distribution of T lymphocytes in normal intestine. The composition of the peritumoral reaction resembled that of normal lamina propria with a predominance of CD3 + CD4 + T cells. In contrast, lymphocytes located between carcinomatous cells showed phenotypical features similar to those of intraepithelial lymphocytes (IEL) in normal intestine; in particu(abstractlar they expressed the antigen defined by HML-1, a monoclonal antibody raised against normal human intestinal IEL which reveals 95% IEL but very few cells in lymphoid (abstractorgans and blood. As normal intestinal IEL, the majority of intratumoral lymphocytes had the CD3+ CD8+ phenotype. A panel of monoclonal antibodies and double immunostaining techniques permitted a better characterisation of minor subsets of IEL. Two subsets of HML1 + CD3 + CD4- CD8- and of HML1+ CD3- cells, representing 2% and 3% of normal intestinal IEL respectively, did not significantly increase in carcinomatous epithelium. In contrast, in carcinomatous epithelium, but not in normal intestinal epithelium, we observed the appearance of a few lymphocytes displaying the phenotype of activated T cells (CD25+) or of natural killer cells (NKHI+) or of suppressor cells (CD11+). Such cells may participate in antitumoral defence. Although a similar population of HML1+ lymphocytes is associated with normal and carcinomatous intestinal epithelium, some interactions between lymphocytes and epithelial cells may not be maintained in tumoral epithelium. It has previously been shown that HLA-DR expression by enterocytes is modulated by intraepithelial lymphocytes. In our study, no correlation could be shown between the degree of lymphocytic infiltration and the expression of HLA-DR antigens on carcinomatous cells.

Adenocarcinoma↗

[Immunohistochemical detection of HBs, HBc and delta antigens in liver sections. Technics, value as a routine procedure according to the cycle of the viral disease and prospects for the future].

The detection of hepatitis B viral antigens and the hepatitis delta viral antigen on liver section is currently facilitated by the production and marketing of good quality antisera and revelation systems. Moreover, the routine application of these techniques in histology departments has become more widespread. The detection of HBs and HBc antigens may be useful in the diagnosis of chronic hepatitis. It allows evaluation of replication of HBV (in the same way as HBe antigen and serum DNA) and the examination of a liver needle biopsy should include, in addition to analysis and classification of the lesions, tests for the presence of these antigens. The detection of the delta antigen is particularly useful for the diagnosis of acute hepatitis delta (in cases of co-infection or secondary infection). On the other hand, it is disappointing for the diagnosis of chronic hepatitis delta.

Antigens, Viral↗

[Voided urinary cytodiagnosis. Cyto-histologic comparison].

The authors report the results of a 4 year study of voided urinary cytology by cytocentrifugation. The findings were compared with those of histology. The sensitivity of the cytological diagnosis varies with the histological grade of the tumor. Grade 1 papillary tumors are not detectable with classical cytological criteria of malignancy. However they may be evoked if finer criteria are considered. Voided urinary cytology is efficient in the detection of grade 2 and grade 3 papillary tumors as well as dysplasia and in situ carcinoma in flat mucosa. The sensitivity of urinary voided cytology is remarkably improved by repeating the examination 3 successive times. This method detects tumors of the urinary bladder as well as those of the upper urinary tract. False positive results are possible, but may be avoided by knowing the clinical history and by repeated urinary cytology. Protocols are proposed for the diagnosis and follow-up of transitional cell tumors. Systematic screening of high risk subjects is also an important indication for voided urinary cytology, but we lack experience in this domain.

Carcinoma in Situ↗

[A case of esophageal papillomatosis in adults].

The authors report the case of a 60 year-old woman patient with esophageal papillomatosis, revealed by slowly progressive dysphagia and digestive hemorrhage. Multiple warty tumors were found at endoscopy, starting at approximately 23 cm from the dental ridge, increasing in size into the lower esophagus where they were responsible for stenosis. Pathological examination demonstrated epithelial proliferation with lengthened papillae, hyperkeratosis, hyperacanthosis and severe dysplasia. No extra-esophageal papillomata were discovered. Subtotal esophagectomy was performed and pathological examination with immune markers suggested a human papilloma virus (HPV) infection. However, search for HPV DNA was negative. To our knowledge, this constitutes the fifth case reported in the literature. The principal problem posed by this rare disease is the possible association with and/or progression to carcinoma, the diagnosis of which may be difficult, and particularly, with verrucous carcinoma. With this diagnostic uncertainty in mind, the authors suggest total surgical removal of the esophagus in this situation.

Esophageal Neoplasms↗

[Digestive lymphomatous polyposis: study of a case diagnosed by rectal biopsy].

We report a case of gastrointestinal lymphomatous polyposis revealed by a rectal tumor. Numerous polypoid lesions, 5 to 20 mm in diameter, were found at various levels of the gastrointestinal tract. Microscopic examination of gastric, duodenal, colic and rectal specimens led to the diagnosis of small cleaved-cell type lymphoma. The immunohistochemical study showed a monotypic surface staining of the lymphomatous cells with anti-IgM, IgD, kappa, C3b, and CD5 antibodies. This type of lymphoma is rare and presents as multifocal polyposis of the gastrointestinal tract. Only histologic and immunohistologic studies can establish diagnosis. Gastrointestinal lymphomatous polyposis is classified as a low-grade malignant lymphoma, with frequent nodal, hepatosplenic, bone marrow, and blood involvement. Chemotherapy is the appropriate treatment.

Aged↗

Lymphoid stromal reaction in gastrointestinal lymphomas: immunohistochemical study of 14 cases.

The lymphoid stromal reaction, particularly the T lymphoid reaction, was studied immunohistochemically on cryostat sections in 14 cases of primary gastrointestinal B lymphomas, and compared with the type and distribution of lymphoid cells in three cases of gastric lymphoid hyperplasia. A pronounced T lymphoid reaction, mainly of the T helper phenotype, occurred in both lesions. Most of these T cells bore HLA-DR antigens, but only a few of them had the receptor for interleukin 2. The T lymphoid reaction was observed inside the lymphomas in seven of a total of 14 cases, and around the lymphomas in four of the six cases clinically classified as stage I. Perivascular mucosal and submucosal nodules, entirely composed of T cells, seemed characteristic of gastric lymphoid hyperplasias. A T lymphoid reaction in lymphoid hyperplasias suggests an amplification of the cell mediated immune response; in lymphomas it could represent a host reaction against the lymphomatous infiltrate, therefore favouring a better prognosis.

B-Lymphocytes↗