2002 SERIES ARTICLES

Therapeutic Drug Monitoring: Issues in Transplantation
By Stephen E. Kahn, PhD, DABCC and Earle W. Holmes, PhD, DABCC
December 2002

As the demand for the number and types of organ transplants has grown, so has the number of analytical options available to clinicians to monitor the level of immunosuppressant drugs. Understanding these options is important as labs will continue to play a major role in the assessment of immunotherapy in transplant patients.

Hepatitis C: Laboratory Tests for Diagnosis and Monitoring of Infection
By D. Robert Dufour, MD
November 2002

Hepatitis C is the most chronic infectious disease in the United States, and can result in cirrhosis, cancer, and ultimately liver failure. A variety of different tests have been developed to diagnose and monitor the virus, and understanding how these tests work is important for how you approach the disease from a clinical standpoint.

SNPs: Will Human Genetic Variation Lead to New Medical Practices?
By Emily Winn-Deen, PhD
October 2002

By studying single nucleotide polymorphisms, tiny variations in the human genome that exist among individuals, scientists are hoping to identify the genetic reasons why some people are more susceptible to disease than others, ultimately leading to better and more personalized treatment options. The first step toward this goal is developing diagnostic tools capable of detecting these mutations and polymorphisms.

Hemoglobin-based Oxygen Carriers: Just Another Interfering Substance?
By Kenneth Ryder, MD, PhD, and Melvin Glick, PhD
September 2002

Hemoglobin, along with other substances naturally found in blood, can interfere with analytical techniques resulting in erroneous test results. Blood substitutes can stabilize these substances to make them less reactive, but the chance of interference still exists. Laboratorians will need to be aware of the potential for assay interference, and know of techniques that will make their results as accurate as possible.

Urinalysis: How to Create an Effective Point-of-Care Program
By Elizabeth E. Porter, MT, ASCP
August 2002

Although urinalysis was one of the first point-of-care tests developed, creating a successful program is still difficult because many regulatory compliance, staff, quality control, and methodology issues must be taken into account.

Human Immunodeficiency Virus: Diagnostic Testing at the Start of the 21st Century
By James P. Grenert, MD, PhD; Patricia S. Nassos, PhD, MT; Barbara L. Haller, MD, PhD
July 2002

In the two decades since HIV was first documented in the United States, very specific testing methods have been developed to detect the virus in infected individuals. Today there is a clear need for the development of more rapid HIV tests that will hopefully help in the struggle to control AIDS.

Adult Blood Lead Testing: A Pivotal Role for Labs in Interpretation and Surveillance
By Michael Ottlinger, PhD; Ralph Zumwalde; Robert Roscoe, MPH; Michael Kosnett, MD, MPH; Karen Hipkins, MPH, RN, NP-C, Raymond Meister, MD, MPH; and Barbara Materna, PhD, CIH
June 2002

Accounts of lead poisoning date back thousands of years, but recent attention has been focused on children, rather than adults, due to the well-known effects of lead on the developing nervous system. No national set of guidelines currently exists for the management of adults with lead poisoning, and this is problematic because the occupational exposure to lead is significant in certain industries.

Total Homocysteine: Guidelines for Determination in the Clinical Laboratory
By Helga Refsum, MD
May 2002

The development of assays to determine the total homocysteine level in patients has become standard for assessing a variety of diseases, including folate deficiency, cardiovascular disease, and homocystinuria. As these tests become more important and widespread in a clinical setting, it is important for healthcare practitioners to understand some basic guidelines regarding the clinical applications of performing this test.

Prostate Cancer: Free PSA Adds Value to PSA Testing
By Martin Knoll, MD
April 2002

Screening for the prostate specific antigen (PSA) has become a useful diagnostic for tracking the progression of prostate cancer, but its usefulness in screening for prostate cancer is not reliable because some men express a high PSA level because of nonmalignant diseases. However, evidence is beginning to show that the free PSA (fPSA) test, when used in conjunction with the standard PSA test, can be an early and accurate way to detect prostate cancer.

Activated Clotting Time: How to Select the Right Assay for the Right Clinical Application
By Marcia L Zucker, PhD, and Frank M LaDuca, PhD
March 2002

Activated clotting time has been used for decades by physicians to determine how much heparin a patient should receive during cardiac procedures. Various assays have been developed to measure activated clotting time, but it is critical to understand how differences in each system will affect clinical applications.

B-type Natriuretic Peptide: A New Marker for Heart Failure
By Scott Mader
February 2002

The analysis of biochemical markers has become a reliable and easy method for diagnosis and monitoring of several diseases. Diagnosing patients with heart failure has, however, been difficult because no protein marker has been developed that is stable, specific, and sensitive enough for an accurate diagnostic test. A possible candidate is the B-type natriuretic peptide, which research has shown could become invaluable for the diagnosis of this disease.

Thrombophilia: Laboratory Evaluation
By Douglas A. Triplett, MD, FCAP, FACP
January 2002

Thrombophilia and its associated complications are the most common cause of death in the Western world. Research suggests that approximately 60% of patients with recurrent thromboembolic events have hereditary and/or acquired risk factors, and the identification of these factors is vital toward providing patient care.