Volume 63 - 2000 - Fasc.3 - Original articles
Prevalence of the Cys282Tyr and His63Asp mutation in flemish patients with hereditary hemochromatosis
Recently Feder et al have identified the gene responsible for hereditary hemochromatosis ; it is located 3 Mbp telomeric of the MHC region on chromosome 6p and is called the HFE gene. The majority of the patients with hemochromatosis harbour the same missense mutation, Cys282@r. A second missense mutation (His63Asp) of which the significance is less clear, has also been described. To our knowledge the percentage of these two missense mutations in Flemish hemochromatosis patients is not known. Materials and methods : Forty nine (49) unrelated patients with the clinical diagnosis of hemochromatosis were screened for the two missense mutations. The missense mutations were diagnosed with a PCR technique. Results : Of the 49 patients, 46 patients were homozygous for the Cys2824r mutation (94%), 2 were heterozygous (4%) and I carried two norirnal alleles (2 %). Of the 3 patients not homozygous for the Cys282@r mutation, 3 were heterozygous for the I-lis63Asp mutation (2 patients were 'compound heterozygotes'). Discussion : The percentage of homozygotes (Cys282@r) in a Flemish hemochromatotic population is comparable with the figures published in the literature. The second missense mutation (His63Asp) could be of importance in association with the Cys282]Nr missense mutation.
Brush cytology of ductal strictures during ERCP
Background: Previous reports on endoscopic retrograde brush cytology (ERBC) of bile ducts and of the main pancreatic duct have reached widely varying sensitivity levels of 33 up to 85 %. Aims: To report our experience with ERBC in a series of biliary strictures (n = 98) and pancreatic duct strictures (n = 8). For the purpose of our study, that was mainly directed to the value of the cytologic examination as such, only those specimens that were considered satisfactory for cytological interpretation were studied. Patients: From October 1988 until August 1994, 154 cytologic brushings were performed at ERCP in 132 patients. In 132 brushings obtained from 115 patients (86%), cell yield was satisfactory for cytologic interpretation. Nine patients lacked adequate followup. Hence, 123 brushings from 106 patients were included in this study. A final diagnosis of malignancy was obtained in 62 patients. Methods: Cytological changes were described as 'benign', 'columnar cell intraepithelial neoplasia', 'inconclusive' by the presence of atypical cells, or 'malignant'. Results : For a positive diagnosis of the malignant nature of a stenosis, EP.BC had an overall sensitivity of 63 % with a specificity of 96 %. One false positive result was obtained in a patient with a biliary infection by Fasciola Hepatica. Sensitivity was highest in malignant ampullary strictures (91%). Sensitivity was 60% for cholangiocarcinomas, and 65% for pancreatic cancer. The finding of 'columnar cell intra-epithelial neoplasia' in the ampullary region led to a Whipple resection and diagnosis of invasive carcinoma in one patient. Atypical cells were found in 4 brush specimens : in three of these 4 cases, a malignant lesion proved to be present. Conclusions : Brush cytology is a simple technique with a high specificity and should be performed in biliary and pancreatic duct strictures of unknown etiology. Categorizing the smears according to cytomorphology may improve diagnostic accuracy.