What is the purpose of drug susceptibility testing (DST) in TB management?

• A. To identify resistance patterns and guide drug choices, enabling effective regimens.
• B. To determine HIV status.
• C. To monitor liver enzymes during treatment.
• D. To assess nutritional status.

Answer: (A)

Drug susceptibility testing in TB management is about identifying which drugs the tuberculosis bacteria are resistant to so the treatment can be tailored to use only effective medications. This makes the regimen more likely to cure the infection, reduces how long the person remains contagious, and helps prevent the spread and amplification of resistant strains by avoiding drugs that won’t work. DST is especially critical when there is a suspicion of multidrug-resistant TB, guiding the use of second-line or newer drugs to construct an effective plan. Tests can be phenotypic, showing how the bacteria grow in the presence of drugs, or genotypic, detecting mutations known to confer resistance, which can speed up decision-making. Other management aspects, such as determining HIV status, monitoring liver enzymes during therapy, or assessing nutritional status, are handled by separate tests and evaluations.