Medical residents score poorly in diagnosing and managing tuberculosis

Aug 3 2007

When quizzed about their knowledge in diagnosing tuberculosis and deciding on the best treatment, medical residents in Baltimore and Philadelphia get almost half the answers wrong, according to a survey by TB disease experts at Johns Hopkins and elsewhere.

In the survey, published online Aug. 2 in the British journal BMC Infectious Diseases, 131 medical residents were asked to answer 20 basic questions about the contagious lung disease, recently made the subject of international concern when a traveler was believed to have its most severe form.

According to researchers, the overall median test score for the training physicians, with one-half scoring higher and the other half scoring lower, was just 55 percent.

Results showed that the recent medical school graduates got three-fifths of the answers wrong (with a median score of 40 percent) for recognizing and treating latent TB, the most common form of the infection. In latent TB, a person is infected with the tubercle bacterium but lacks symptoms and is not contagious, yet is still at risk for developing active disease later on.

Just over half of the questions about diagnosing active TB, when an infected person develops TB-related symptoms and is more likely to infect others, were answered correctly (with a median score of 57 percent). Symptoms of active TB include fever, cough, night sweats and weight loss.

According to the U.S. Centers for Disease Control and Prevention, an estimated 10 million to 15 million Americans have latent TB and are at risk of developing active disease.

On two-thirds of the questions about the toxicity of current drug regimens and about the link between TB and HIV infection, physicians gave the right answer (with a median score of 63 percent for both questions.)

"Despite the poor results for trainees, people cannot assume that lack of comprehensive knowledge about tuberculosis leads to poor patient care," says lead study author Petros Karakousis, M.D. "Medical residents may be quick to consult experts in infection control, infectious diseases, or in pulmonary medicine to assist in diagnosis, isolation and treatment."

According to Karakousis, an assistant professor at The Johns Hopkins University School of Medicine and its Tuberculosis Research Center, "Our results demonstrate that improved training is needed about how best to diagnose and care for people with latent and active TB because physicians training at urban medical centers are most likely to be the first point of contact for people with previously undiagnosed TB."

Karakousis says large metropolitan areas are prone to more cases of TB because of social factors, including high rates of homelessness, drug use, incarceration and immigration, as well as HIV infection.

He points out that the survey results were not all bad, with most medical residents understanding the main facts about how Mycobacterium tuberculosis is transmitted (with a median score of 95 percent).

"Most people with active TB develop symptoms over weeks, so what is needed is more training in the outpatient setting and in the community in addition to the hospital wards, to recognize and treat this infection early and before it spreads," Karakousis says.