The Johns Hopkins Gazette: March 20, 2000
March 20, 2000
VOL. 29, NO. 28


TB Therapy Requires Experts, Hopkins Investigation Finds

By Kate O'Rourke
Johns Hopkins Gazette Online Edition

A study by infectious disease experts at Johns Hopkins concludes that public health doctors do a far better job of treating tuberculosis than do private-practice physicians. Results strongly suggest that private doctors are responsible for most of the drug-resistant TB cases emerging in the United States, the study's authors say.

"In the United States, TB is now uncommon enough and its treatment complex enough that it should only be treated by an expert," says Richard Chaisson, a professor of medicine and senior author of the study that appears in the March issue of Chest. "If this is not feasible, there needs to be training and adequate support in monitoring private physicians so they make fewer errors."

In the United States, the number of TB cases has dropped substantially in recent years, and many doctors have little experience with treating the disease properly. Antibiotics normally knock out the bacillus that causes TB, but without the proper combination of drugs for the proper amount of time, some bacilli become drug resistant, worsening the problem and complicating treatment. Good TB therapy generally requires a six-month drug regimen involving four drugs.

For several years, researchers have known that patients treated at clinics run by public health departments have better outcomes than do patients treated by private physicians. They didn't know, however, whether the clinics were better at treating their patients or whether the patients who received care at the clinics were just better at taking their medications.

To examine the treatment conundrum, experts at Hopkins collected the files of all infectious TB cases reported in Baltimore between January 1994 and December 1995. Excluding cases diagnosed after death and those with incomplete medical files, they examined the records of the remaining 110 cases, 34 treated by private physicians and 76 at the Tuberculosis Clinic at the Baltimore City Health Department.

The researchers found that 15 percent of the total had serious errors in their treatment for TB and that private physicians treated 77 percent of these patients. Of those who were treated erroneously, eight patients received inadequate doses of anti-TB drugs, four were put on inappropriate combinations of drugs, three were not treated for the full six months, and two were put on inadequate dosages as well as not treated long enough.

"Inappropriate treatment generally reflected a lack of familiarity with the treatment guidelines," said Chaisson. "Because in the United States, TB is so uncommon, most doctors will not see a single case of TB in any given year, whereas a city's health department may see up to 100 cases in a year. You can't expect a private physician to be up on all the guidelines compared to a group that sees TB patients all the time." According to Chaisson, the most efficient way to avoid treatment errors and the development of drug-resistant strains is to have all TB patients treated by a health department or by those specializing in TB treatment. If this is not possible, he says, private physicians who treat TB patients should be monitored.

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