TB patient classification based on drug testing

Type of drug resistance 

Description 

Mono-Drug Resistant 

Resistance to only one first-line anti-TB drug
(other then Rifampicin)

Rifampicin resistant

Resistance to Rifampicin (R) alone

H-Mono resistant 

(Most common)

Resistance to Isoniazid (H) alone

Poly drug resistant 

Resistance to ≥2 any TB drug 

(other than Rifampicin & Isoniazid)

MDR-TB

Resistance to Isoniazid (H) and Rifampicin (R)

Pre-XDR TB

MDR-TB + Fluoroquinolone (FQ)

XDR TB

Pre-XDR TB + Any Group A second-line drug
(Bedaquiline, Linezolide)

Presumptive MDR-TB

TB Patients with Treatment Failure- 

• Failure of new TB regimen (Category I)

• Failure of previously treated TB regimen (Category II)

Previously Treated TB Patients- 
Any TB patient previously treated with anti-TB drugs,
especially if:

• Loss to follow-up

• Relapse cases

• Re-treatment cases

Close Contacts of MDR-TB Cases- 

Household or close contacts of confirmed MDR-TB
patients, whether symptomatic or not.

Positive Follow-up Smear/ Culture During Treatment- 

Patients who are still smear-positive or culture-positive
at or after 2–3 months of treatment.

HIV-TB Co-infected Cases (High-Risk Groups)- 

Especially if treatment response is poor or patient is
deteriorating clinically.

Groups 

Drugs 

Group A

• Bedaquiline

• Linezolid

• Levofloxacin / Moxifloxacin

Group B

• Clofazimine

• Cycloserine / Terizidone

Group C

(These are add-on agents 

if A or B drugs are
not suitable)

• Delamanid

• Ethambutol

• Pyrazinamide 

• Imipenem-cilastatin / Meropenem

• Amikacin / Streptomycin

• Ethionamide / Prothionamide

• p-Aminosalicylic acid (PAS)