Drug-resistant forms of the bacteria responsible for tuberculosis infections are difficult to identify, hard and expensive to treat, and represent a major global threat to public health. However, University of California, San Diego School of Medicine researchers have documented the accuracy of three new tests for such strains of pathogenic microorganisms.
"Our study shows that TB testing that once took two to three months can now be done in as little as a day," Richard Garfein, PhD, professor in the division of Global Public Health at UC San Diego School of Medicine and co-author of the paper, said in a statement. "This means we can put people on the right medications sooner, spare them the toxic effects of drugs that are ineffective and prevent the development of drug resistant forms of TB that can occur when the wrong medications are given."
Two of the tests use molecular techniques to search for genetic mutations in the bacteria's DNA that enable its resistance. The third uses a low cost alternative to the standard culture technique, making it ideal for resource-limited community hospitals. The two molecular techniques returned results with a mean time of 1.1 days, compared to 14.3 days for the culture method and 24.7 for the standard reference method.
When compared with standards techniques for detecting resistance to the most important anti-tuberculosis drug, results from all three tests reflected accurate identifications to first- and second-line oral antibiotic treatments, according to the paper, published in the journal PLOS ONE. They were less accurate, but still efficient, at detecting resistance to injectable antibiotics.