New Mexico patients may have access to a better diagnostic method for tuberculosis in the future. At Stanford University School of Medicine, researchers have developed a blood test that identifies tuberculosis in children with a positive result accuracy of 86 percent. The World Health Organization has called for a test that has a 66 percent positive accuracy with children. Researcher say its negative results are 99 percent accurate.
Prior tests for tuberculosis have been unable to distinguish between someone who has an active case of the disease and someone who has been vaccinated against the disease. One test identifies bacterium in sputum samples, but it can be difficult to get people to produce sputum. Some doctors have failed to diagnose tuberculosis in patients who have HIV.
The test, named the Khatri test for the lab in which it was developed, can also monitor how a patient is responding to treatment. While this is also possible with a sputum test, people often cannot produce sputum at all as they improve. The next step will be using the test in clinical trials that monitor people’s progress as well as for diagnosis. According to the Centers for Disease Control and Prevention, tuberculosis kills 1.5 million people worldwide annually, and about 33 percent of the population of the world is infected with the disease.
Misdiagnosing or failing to diagnose a disease can affect a person’s prognosis. A doctor may fail to diagnose an illness because there is not an accurate test, as has been the case with tuberculosis, or for other reasons. For example, a person with cancer might not have a medical history that suggests cancer, or a doctor may dismiss a person’s symptoms. People who think that they may have been misdiagnosed due to negligence may want to discuss their situation with an attorney.