[Initial Dutch results with a presymptomatic DNA tests in familial breast/ovarian carcinoma. Rotterdamse Werkgroep voor Erfelijke Tumoren]. / Eerste Nederlandse ervaringen met een presymptomatische DNA-test bij familiair mamma-/ovariumcarcinoom. Rotterdamse Werkgroep voor Erfelijke Tumoren.

Recent discoveries in the field of molecular-genetic research make it possible to detect an increased genetic risk of tumours, because several genes are linked to hereditary forms of breast cancer. The breast cancer gene BRCA1, located on chromosome 17q, is quantitatively the most important gene so far. A BRCA1 gene mutation is estimated to occur in 1-3 per 1000 women in the general population, i.e. in about 10,000 women among the 4 million Dutch women aged 25-55 years. In this study experiences are described concerning oncologic, clinical-genetic and psychologic aspects in the first Dutch family in which a BRCA1-gene defect was detected with the corresponding hereditary breast/ovarian cancer syndrome. Of the relatives 88% participated in the genetic family study and 76% wished to be informed on the individual DNA-test results. From the first-degree relatives of the breast cancer patients 54% appeared to be gene mutation carrier. The detection of a gene mutation in a woman could make her decide to undergo preventive mastectomy and (or) ovariectomy, besides regular breast examination and mammography. Surgeons and radiotherapists, the group of doctors who treat primary breast cancer, have to anticipate more radical operations with regard to breasts in this selected group of (future) patients. Detection of the gene may also have consequences for family planning. Identification of carriers of the gene mutation can lead to a selection of women with increased risk of breast cancer. Primary or secondary preventive measures, early diagnostic management and regular examination may lead to a decrease in death from breast cancer.

Results of 1-year screening of donors in The Netherlands for human T-lymphotropic virus (HTLV) type I: significance of Western blot patterns for confirmation of HTLV infection.

BACKGROUND: Between January 1993 and January 1994, Dutch blood banks screened approximately 674,000 volunteer donors for the presence of antibodies to human T-lymphotropic virus type I (HTLV-I). STUDY DESIGN AND METHODS: Confirmatory testing was performed on samples from 870 different anti-HTLV-I-reactive donors (0.13% of the total tested). RESULTS: According to the authors' Western blot (WB) interpretation criteria, 15 (0.002%) donors tested HTLV-I-positive in the WB; 201 tested negative, and 654 (75% of donors reacting on enzyme-linked immunosorbent assay) tested indeterminate. Fresh samples from 234 of 870 anti-HTLV-reactive donors were tested for HTLV-I and type II (HTLV-II) DNA by polymerase chain reaction: all 15 WB-positive donors tested positive for HTLV-I DNA; 206 WB-indeterminate and 13 WB-negative donors tested negative for HTLV-I and -II DNA. Application of the manufacturer's (World Health Organization-based) guidelines for WB interpretation would have resulted in the misclassification of 48 (23%) of 206 polymerase chain reaction-negative donors as HTLV-I/II-positive. Risk factors were present in 14 of 15 HTLV-I-infected donors: 8 had a partner from an HTLV-I-endemic area, 4 were from HTLV-I-endemic countries, and 2 had received blood transfusions. CONCLUSION: HTLV-I and -II infection is rare among Dutch blood donors. HTLV screening will prevent few cases of HTLV-related disease, but it will prevent a further spread of the virus by transfusion. In a low-risk population, conservative guidelines for WB interpretation unnecessarily generate an excess of false-positive results.

[Prevalence of human T-cell lymphotropic virus type I among Dutch blood donors]. / De prevalentie van humaan T-lymfotroop virus type I onder Nederlandse bloeddonors.

OBJECTIVE. To establish the prevalence of human T-lymphotropic virus (HTLV) type I among Dutch blood donors. DESIGN. Study to confirm screening results. SETTING. Central Laboratory of the Blood Transfusion Service of the Dutch Red Cross, section Virus Diagnostics, Amsterdam. METHOD. The majority (550,000) of the Dutch blood donors were tested in the course of 1993 for presence of HTLV antibodies. For serological confirmation using the Western Blot test, 20 of the 22 Dutch blood banks sent in blood samples of 714 donors found positive at HTLV screening. Material of 36 of these donors was suitable for testing using the polymerase chain reaction (PCR) for DNA of HTLV types I and II. RESULTS. The Western Blot confirmation test confirmed HTLV infection of 10 of the 714 blood donors; eight of these samples, examined with the PCR test, proved to be positive for DNA of HTLV I. In 537 of the 714 ELISA-reactive donors, the Western Blot test gave doubtful results. The PCR test for HTLV I/II DNA was negative in 26 of these samples, but the possibility could not be excluded that there were HTLV carriers among the other donors with a doubtful Western blot test result. With inclusion of the four donors infected with HTLV I that had been detected earlier, the prevalence of HTLV I among Dutch blood donors is found to be 1:39,000.

[Revised definition of the concept rhesus-negative blood donor; practical experiences]. / Herziene omschrijving van het begrip rhesus-negative bloeddonor; de ervaringen in de praktijk.

In 1987 the Central Medical Blood-transfusion Committee of the Netherlands Red Cross decided to modify their definition of 'Rh-negative' as it applied to blood donors. Until then the term Rh-negative had been reserved for donations that grouped as C- and E-negative and failed to react with IgG anti-D by the indirect antiglobulin test (IAT). From June 1987, however, donations were considered to be Rh-negative if they failed to react with two strong anti-D sera. An evaluation is presented over the first one and a half years of working with the new definition, the problems that were encountered and the measures that are taken to guarantee the quality of Rh testing.

A Dutch blood bank and its donors.

Through the aid of a questionnaire, a group of prospective donors, donors and ex-donors was studied. The most important incentive to become a donor was the direct approach by another donor. The most important motives were altruistic in nature and the medical check-up which is a part of donation. The complaints and objections of donors related to the medical check-up, the distance traveled to the site of the medical examination and blood collection and the rather impersonal way donors were treated. The most important reasons why ex-donors had stopped giving blood referred to medical complaints, practical inconveniences, physical reactions to the giving of blood, the impersonal approach and the fear of detrimental side-effects of the giving of blood. The Dutch system, whereby no financial remuneration is offered for the donation of blood, appears to function satisfactorily. The survey justifies future research aimed to a greater degree on the connection between the motives of the donor and the way the blood bank functions.