News
FDA limits antibiotics for livestock. Concerned that the practice of providing cattle, pigs, chickens, and turkeys with a common class of antibiotics may be contributing to the increase in antibiotic-resistant bacteria, the Food and Drug Administration (FDA) ordered ranchers and farmers to limit the drugs ingested by livestock being bred for food. The drugs, known as cephalosporins and including such brands as Cefzil and Keflex, are often added to feed and water to increase the robustness of the livestock. They are the same antibiotics that are frequently prescribed for the treatment of pneumonia, urinary tract infections, and strep throat in humans. They are also often prescribed before surgery. Many microbiologists believe the use of the drugs in animals has paved the way for the appearance of bacteria against which they are ineffective, at the cost of perhaps thousands of human lives.
The restriction is reminiscent of the FDA's ban on agricultural uses of fluoroquinolones, including Cipro, in 2000, and is comparably controversial. Rep. Louise Slaughter (D-New York), who is a microbiologist, applauded the FDA action, even as she suggested it was insufficient: “We are staring at a massive public health threat in the rise of antibiotic-resistant superbugs.” Dr. M. Gatz Riddell of the American Association of Bovine Practitioners, however, said antibiotics use in animals is “highly misunderstood in the human-health community” and that its dangers have been exaggerated.
Lack of labs hinder healthcare in Ghana. At a meeting of the Eastern Regional branch of the Ghana Association of Biomedical Laboratory Scientists (GABMLS), biomedical scientist George Danquah reported grim news: In the eastern region of the West African nation, only the regional and district hospitals provide laboratory services; some 60 other medical facilities there have no lab services. Danquah, speaking at a conference themed around “linked the lack of medical laboratories to the nation's high rate—two percent—of sickle cell births. He and other speakers appealed for assistance from other nations of Africa and from abroad, noting as major issues a great need for refrigerated centrifuges to prepare fresh frozen plasma and a short supply of reagents. Experts reported that other problems range from the lack of a robust health surveillance system to report disease outbreaks, to a scarcity of trained biomedical engineers to repair malfunctioning equipment, to an absence of effective regulations.
Guidelines
CLSI issues new guidelines on molecular testing. The Clinical and Laboratory Standards Institute (CLSI) recently published Establishing Molecular Testing in Clinical Laboratory Environments: Approved Guideline. This document provides comprehensive guidance for planning and implementation of molecular diagnostic testing, including strategic planning, regulatory requirements, quality management, and special considerations for the subspecialties of molecular genetics, infectious diseases, oncology, and pharmacogenetics. The guideline's target audience is the stakeholders who play a role in the strategic decision to implement a molecular diagnostic program, including medical and technical directors who may not have previous experience with molecular testing; supervisory technical staff who implement molecular assays for the first time; and production staff who will perform and maintain all aspects of the assays.
Genetic Testing
New prenatal test can detect trisomy 18 and trisomy 13. A study published in the journal Genetics in Medicine reports that trisomy 13 (Patau syndrome) and trisomy 18 (Edwards syndrome) can be detected by a newly available DNA-based prenatal test. Infants born with either chromosomal abnormality, both of which are related to the most common trisomy, Down syndrome (trisomy 21), have a grim prognosis: Up to 70% of fetuses who are affected by trisomy 18 result in miscarriages; of live births, about half die within a week and only one in 20 live for one year. Trisomy 13, though less common, is equally serious; both 18 and 13 are characterized by cognitive and developmental disabilities and severe problems affecting most body systems. The new blood test can detect trisomies 13, 18, and 21 and gives pregnant women an alternative to more invasive diagnostic testing. Study authors indicated that the new test has high rates of accuracy; it identified 100% of trisomy 18 pregnancies and 92% of trisomy 13 pregnancies, and false positives were less than one percent for both syndromes.
Cancer
Genomic Health study shows positive result of new colon cancer RS test. Genomic Health, Inc., announced results of the first clinical decision-making study of the Oncotype DX colon cancer test that shows the Recurrence Score (RS) result has a significant impact on treatment recommendations for stage II colon cancer patients. The data, presented at the 2012 Gastrointestinal (GI) Cancers symposium, indicate that knowledge of a patient's Recurrence Score changes medical oncologists' treatment recommendations in 29% of cases. These results are consistent with the change rate of approximately 30% that has been observed in studies evaluating the impact of the Oncotype DX breast cancer test on treatment decisions in early-stage breast cancer.
To characterize the impact of the Oncotype DX test on adjuvant treatment recommendations in stage II colon cancer, U.S. medical oncologists who had used the test on three or more patients participated in a survey to assess how the Recurrence Score impacted their treatment decisions. Of 92 patients who had treatment recommendations before having Oncotype DX testing, physicians changed treatment recommendations based on the Recurrence Score results in 27 patients (29%).Two-thirds (67%) of changes in recommendations were decreases in treatment intensity (changes from chemotherapy to observation or from oxaliplatin-containing chemotherapy to treatment with fluoropyrimidine monotherapy); one-third (33%) were increases in treatment intensity. The 12-gene colon cancer Recurrence Score assay was developed using data from 1,851 patients in four independent studies conducted with the National Surgical Adjuvant Breast and Bowel Project (NSABP) and Cleveland Clinic.
Infectious Diseases
An ominous report published in the New England Journal of Medicine suggests that gonorrhea is becoming increasingly resistant to antibiotic treatment. For the last few years, an increasing number of cases of the sexually transmitted disease have not responded to the conventional last-line treatment, which uses cephalosporins. Investigators writing in NEJM have expressed concern that one of humanity's ancient bacterial enemies may soon have to be considered untreatable. This news of gonorrheal antibiotic resistance follows closely on reports of the identification of a strain of e.coli bacteria with drug-resistant genes, pneumonia that has developed resistance to antibiotics of last resort called carbapenems, and unconfirmed reports of untreatable cases of tuberculosis in India.
