An article review: Diagnosis and treatment strategies for drug-resistant tuberculosis

The management of DR-TB has been altered by oral anti-TB drug regimens, which are more effective and less toxic, generally better tolerated, and improve adherence and efficacy
.
The principles for the treatment of DR-TB regimens are outlined in accordance with the latest WHO recommendations, and Table 1 shows the WHO steps to classify MDR-TB drugs and establish a long-term MDR-TB regimen
.

Table 1 constructs the WHO MDR-TB drug classification for long-term MDR-TB regimens

Treatment of DR-TB requires a regimen of at least 4 drugs to improve efficacy, reduce recurrence rates and prevent the further development
of drug resistance.

For patients with MDR-TB/rifampicin-resistant tuberculosis (RR-TB) (iFluoroquinolone resistance in ii drug susceptibility test (DST) not previously received second-line TB for more than 1 monthiii without extensive pulmonary tuberculosis disease (cavitation) or severe extrapulmonary tuberculosis (spine/central nervous system/miliary)], the recommended regimen is a short-course oral regimen containing bedaquinoline: Bdq (6 months)-LFX / during an intensive period of 4-6 months/ MFX-Z-E-HIGH-DOSE ISONIAZID(H)-ETO, CONTINUED ORAL LFX/MFX-CFZ-Z-E
for 5 months.
The intensification period can be extended from 4 months to 6 months (pending sputum smear and culture to turn negative), and continuation is recommended for 5 months
.
All drugs in this regimen are given once daily except for Bdq, once daily for the first 2 weeks and three times
a week for the next 22 weeks.
Fewer adjustments can be made (i.
e.
replacing Eto with Pto or Lfx with Mfx).

However, compared with Mfx, Lfx has fewer adverse events and less QTc prolongation, so it is often the drug
of choice.
It is important
to also have proactive anti-TB drug safety monitoring and management (aDSM) and to accurately record and manage all adverse events.

Patients outside of these conditions require individualized long-term treatment options
.
WHO-recommended drug prioritization groups aid in the design of this protocol (Table 1), using the following key principles, including at least three group A drugs (i.
e.
, Bdq, Lfx/Mfx, and Lzd) and at least one group B drug (Cs/Trd and/or Cfz).

If groups A and B drugs do not meet the regimen due to resistance or tolerance, group C drugs
are added.
The duration of the individualized longer regimen is 18 months
.

Bdq, pretonamid, and Lzd regimens (BPaL) for 6 to 9 months can be used in patients
with MDR-TB/RR-TB/Quasi-Extensively Resistant Tuberculosis (pre-XDR-TB) who have not been previously exposed to bedaquiline or Lzd (defined as < 2 weeks).
The use of BPaL schemes requires aDSM<b11>.

In addition, recent research evidence suggests that MDR-TB is one of the causes of post-TB lung disease, with up to 50% of patients developing obstructive, restrictive, or mixed lung impairment after TB treatment, reduced exercise tolerance and reduced quality of life during the 6 minute walk test, requiring pulmonary rehabilitation
.