A randomized trial of clinical outcomes for patients with drug-resistant tuberculous meningitis underscores that new diagnostic tools and treatments for the disease are critically needed, authors of a report in the July Clinical Infectious Diseases write. Their study found early identification of drug-resistance and intensified treatment to be pivotal in improving survival chances of people with the disease, the most fatal form of TB, that also is among the most difficult to detect. Even with treatment, the disease kills about a third of patients who have it the authors note.
Accounting for only about five percent of all cases of tuberculosis outside the lungs, tuberculous meningitis is most common in countries with limited health resources, and in children under four years old, but has risen among adults with the spread of HIV. Still no optimal treatment for drug-resistant tuberculous meningitis has been identified, or investigated.
Researchers randomized patients from two hospitals in Ho Chi Minh, Vietnam to standard or intensified treatment, that depended on the drug resistance identified in cerebrospinal fluid. They found significantly higher survival rates among patients whose disease was resistant to isoniazid who were given additional doses of rifampicin, particularly among those who were not also HIV-infected. The finding is important, researchers write, because tuberculosis that is resistant to treatment with isoniazid is increasing, and associated with poorer outcomes. Identifying the drug resistance early is essential they note, but while the World Health Organization recommends the Xpert MTB test for initial testing of cerebrospinal fluid for patients with tuberculous meningitis, the test does not currently detect isoniazid resistance.