The benefits of the Papanicolaou Society of Cytopathology System for reporting pancreatobiliary cytology: A 2-year review from a single academic institution.

OBJECTIVE: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an essential tool in the diagnosis of pancreatic lesions. The aim of this study was to evaluate the diagnostic accuracy of cytology from EUS-FNA, to correlate the results with the corresponding histopathological diagnoses and to analyse the impact of retrospective assignment of the Papanicolaou Society of Cytopathology (PSC) reporting system categories. METHODS: All pancreatic FNA specimens reported at the Royal Free Hospital during a 2-year period were retrospectively collected and assigned to the PSC system categories. Any available corresponding histological samples were assessed for concordance. RESULTS: In total, 236 cytology specimens from 223 patients were identified, of which 108 (45.8%) had corresponding histology samples. The main reason for cyto-histological discrepancy was sampling error. Interpretive error was identified in one case. Overall, sensitivity was 92.5%, specificity was 100%, diagnostic accuracy of cytology was 95%, false-positive rate was 0% and false-negative rate was 7.5%. The implementation of the new reporting system reduced the number of cases in the atypical category. All cases previously categorised as suspicious or malignant remained in the same category. CONCLUSIONS: EUS-FNA is an accurate method for evaluating pancreatobiliary lesions. The implementation of the Papanicolaou Society of Cytopathology diagnostic system enhances standardisation of the reporting terminology and reduces the number of samples in the non-standardised and equivocal atypical category.

Reduced transforming growth factor-beta1-producing T cells in the duodenal mucosa of children with food allergy.

Infant food allergies are increasing, and many breast-fed infants now sensitize to maternally-ingested antigens. As low-dose oral tolerance requires generation of suppressor lymphocytes producing TGF-beta1 (Th3 cells), we studied these cells in duodenal biopsies after diagnostic endoscopy. Spontaneous production of Th1, Th2 and Th3 cytokines by duodenal lymphocytes was studied using flow cytometry in 20 children with no eventual clinico-pathological diagnosis (controls), 30 children with multiple food allergy, nine with celiac disease and six with inflammatory enteropathies. Immunohistochemistry and in situ hybridization were used to localize TGF-beta1 protein and mRNA in matched biopsies. We found no significant Th1/Th2 skewing amongst mucosal lymphocytes in allergic children compared to controls, although celiac and inflammatory enteropathy patients showed increased Th1 responses. By contrast, the allergic children showed reduction of TGF-beta1(+) lymphocytes in both epithelial and lamina propria compartments. Reduction of TGF-beta1 expression was also seen in mononuclear cells and epithelium in food allergy by immunohistochemistry and in situ hybridization. The dominant mucosal abnormality in food allergic children was, thus, not Th2 deviation but impaired generation of Th3 cells. As generation of these cells requires innate immune response to enteric bacteria, we suggest that changing infectious exposures may inhibit primary establishment of basic oral tolerance mechanisms.

Alfa-Naftil acetato estearasa en sangre de cordón de recién nacido

Se seleccionaron 42 muestras de sangre de cordón umbilical para estudiar las subpoblaciones de linfocitos T (auxiliadores y supresores) mediante la prueba de Alfa-Naftil Acetato Estearasa (ANAE), y los resultados se compararon con un grupo control constituído por 44 adultos, donantes voluntarios del Banco de Sangre Provincial. En la prueba de ANAE realizada a los linfocitos T purificadores mediante el uso de fibra de nylon se obtuvo que Tu fue de 79 (más-menos) 4,8 porciento y TY de 21 (más-menos) 4,8 porciento en adultos, contra 65,88 (más-menos) 4,4 porciento para TU y 33,85 (más-menos) 4,3 porciento para TY en recién nacidos, lo que refleja diferencias de alta significación estadística. Se valora la posible inmadurez funcional de los linfocitos del neonato (AU)

Cuantificación de linfocitos T auxiliadores y supresores en adultos y recién nacidos

Se estudiaron las subpoblaciones de linfocitos T auxiliadores y supresores en sangre de cordón umbilical mediante anticuerpos monoclonales IOR T4 y T8 producidos en el Instituto Nacional de Oncología y Radiología ("cluster" de diferenciación 4 y 8 respectivamente), para valorar el estado inmunológico en 30 recién nacidos a término, con peso normal (grupo estudio). Los resultados fueron comparados con el grupo control, constituído por 21 donantes voluntarios sanos con edades entre 18 y 30 años. En células mononucleares periféricas de adultos, los valores para T4 fueron de 46,9 (más-menos)1,67 y para T8 de 26,7 (más-menos) 2. En sangre de cordón umbilical se halló para T4 un valor de 39,56 (más-menos) 2,8 y de 49,13 (más-menos) 4,4 pata T8, por lo que existen diferencias altamente significativas entre ambos grupos. Se valoró la posible inmadurez funcional de los linfocitos en el neonato (AU)