Clinical laboratory reports in molecular pathology.

Context: Molecular pathology is a rapidly growing area of laboratory medicine in which DNA and RNA are analyzed. The recent introduction of array technology has added another layer of complexity involving massive parallel analysis of multiple genes, transcripts, or proteins.

Objective: As molecular technologies are increasingly implemented in clinical settings, it is important to bring uniformity to the way that test results are reported.

Impact of molecular (DNA) testing on determination of parentage.

Objective: To examine changes in parentage testing practices since the introduction of DNA polymorphisms.

Methods: Comparison of data from American Association of Blood Banks (AABB) annual questionnaires and the responses of participants to AABB-College of American Pathologists proficiency test panels.

Results: DNA polymorphisms have led to a complete change in the technical methods used by parentage testing laboratories.

Improving the safety of transfusion therapy.

Enormous strides have been made to reduce the risk of transfusion-transmitted disease. Additional tests to eliminate transfusion-transmitted disease are costly, in terms of both health care resources and availability of volunteer donors. Future improvements in safety probably will require postdraw treatment of blood and components and the use of pharmacologic agents as a substitute for transfusion.

Long-term follow-up of blood donors with indeterminate human immunodeficiency virus type 1 results on Western blot.

Background: At present, tens of thousands of United States blood donors who are at low risk for human immunodeficiency virus type 1 (HIV-1) infection are indefinitely deferred. These persons are repeatably reactive for HIV-1 antibody in enzyme immunoassay (EIA) and are indeterminate in Western blot.

Study Design And Methods: To determine the significance and persistence of anti-HIV-1 reactivity in plasma from volunteer blood donors with HIV-1-indeterminate Western blots, 66 donors were retested for HIV-1 antibody by the same manufacturers' EIA and Western blot 5 to 7 years after the initial Western blot.

Evaluation of clinical and laboratory aspects of antibody tests for detection of hepatitis C virus infection in blood donors and recipients from a low-risk population.

Background: When the first-generation enzyme immunoassay (EIA) for detection of antibody to hepatitis C virus (anti-HCV) was approved in May 1990, blood banking agencies recommended testing of all components in inventory. In many cases, one or more components from these units had already been transfused.

Study Design And Methods: Donors that reacted in first-generation EIAs and recipients of their components were identified, and anti-HCV test methods (including first-generation EIA, second-generation EIA, and recombinant immunoblot assay [RIBA]) were evaluated.

A novel variant of the human blood group K1 antigen.

A discrepancy in duplicate anti-K1 typing in a parentage case led to the discovery of an unusual K1 blood group antigen. Red blood cells from the propositus (JC) express a rare variant of the K1 antigen that is detectable by only 8 of 72 sera containing anti-K1. Absorption and elution studies using reactive anti-K1 confirmed the presence of a K1 antigen.

The 1990 Comprehensive Blood Bank Surveys of the College of American Pathologists.

The performance of participants on the 1990 Comprehensive Blood Bank Surveys of the College of American Pathologists was consistent with the high quality of past surveys. The surveys include challenges in ABO and Rh typing, crossmatching, transfusion decisions, unexpected antibody detection and identification, and supplemental questions to assess contemporary practices. As in previous years, a recurrent serologic problem has been the reporting of antibodies not present in serum (anti-E in Set J-B, and anti-K in Set J-D).

Safety in transfusion practices. Preventing infectious complications.

The benefits of transfusion therapy must always be weighed against the unavoidable chance of an infectious complication. Strategies to minimize the infectious risks inherent in the use of human blood and blood components can be categorized under four general headings: donor selection, testing, appropriate use, and follow-up and reporting of complications. The application of these strategies in the context of their role in the prevention of some of the infectious complications of transfusion therapy is discussed in this article.

The magnitude and origin of European-American admixture in the Gila River Indian Community of Arizona: a union of genetics and demography.

Complementary genetic and demographic analyses estimate the total proportion of European-American admixture in the Gila River Indian Community and trace its mode of entry. Among the 9,616 residents in the sample, 2,015 persons claim only partial Native American heritage. A procedure employing 23 alleles or haplotypes at eight loci was used to estimate the proportion of European-American admixture, m(a), for the entire sample and within six categories of Caucasian admixture calculated from demographic data, md.

The 1988 comprehensive blood bank survey of the College of American Pathologists.

An average of 2211 laboratories reported results in this comprehensive blood bank survey. In general, the participant performance remains strong in ABO and D typing, unexpected antibody detection and identification, crossmatching, and antigen identification. However, certain samples achieved less than the usual performance levels.

Fetomaternal hemorrhage: incidence, risk factors, time of occurrence, and clinical effects.

Most women have only very small amounts of fetal blood in their circulations following pregnancy and delivery: the volume is less than 0.5 mL of whole blood in 93 percent of women, less than 1 mL in 96 percent, and less than 2 mL in 98 percent. FMH of 30 mL or more occurs in just 3 of 1000 women.

Human immunodeficiency virus type 1 proficiency testing. The American Association of Blood Banks/College of American Pathologists Program.

The American Association of Blood Banks/College of American Pathologists Viral Marker Survey program added samples to evaluate participant performance with test systems for the detection of antibodies to human immunodeficiency virus type 1 in 1985. On the 80 challenges sent through April 1989, the major problem observed with enzyme immunoassay testing was unexpected reactivity on samples that did not contain anti-human immunodeficiency virus type 1. One manufacturer's testing system accounted for most of the specificity problems.

Microcomputer-generated antigen panel worksheets.

Many antibody identifications require testing with cells of rare or uncommon phenotypes. To expedite the resolution of these identifications, we developed a microcomputer database using Lotus 123 to enter antigen phenotypes from our frozen cell inventory. Data is entered into a customized screen input form and automatically copied to the database The use of an input form protects the database from inadvertent errors made while entering data.

Genetic structure of Mennonite populations of Kansas and Nebraska.

We describe the gene frequency distributions for 29 different blood group, serum, and erythrocytic proteins for three Mennonite communities from Kansas and Nebraska and compare their gene frequencies with those of Amish, Hutterite, and Mennonite populations using the topological method of Harpending and Jenkins (1973). Subdivision of these communities into congregations reveals that the "fission-fusion'h model best characterizes the relationship between the genetic patterns and historical events. These Mennonite populations, although reproductively isolated at the turn of this century, are presently entering the mainstream of US rural culture.

Performance characteristics of serologic tests for human immunodeficiency virus type 1 (HIV-1) antibody among Minnesota blood donors. Public health and clinical implications.

Study Objective: To evaluate performance characteristics of sequential enzyme immunoassay (EIA) and Western blot human immunodeficiency virus type 1 (HIV-1) antibody testing in a low-risk population.

Design: Three-year prospective study of a selected sample from a community-based population.

Setting: Two blood collection facilities in Minnesota.

Transfusion-associated hepatitis C virus (non-A, non-B) infection.

Non-A, non-B (NANB) is a term used to describe viral hepatitis not due to hepatitis B virus or hepatitis A virus. Two forms of NANB hepatitis have been identified: (1) an epidemic type usually transmitted enterically and (2) a parenterally transmitted form caused by hepatitis C virus. While the latter often is assumed to be transfusion transmitted, data from surveillance programs suggest that the incidence of NANB transfusion-associated hepatitis (TAH) is decreasing.