54

EDITORIAL

Multidrug Resistant Tuberculosis and Importance of DOTS
Iqbal Ahmad Khan

Correspondence:
Prof. Iqbal Ahmad Khan
Head of Department of community medicine /Public Health
Women Medical and Dental College, Abbottabad 
E-mail: profkhakwani@gmail.com

Received: May 01, 2019; Accepted: May 25, 2019

Globally millions of people become sick each year 
with tuberculosis and it is one of the top 10 causes of 

1 
death worldwide. According to World Health 
Organization (WHO), the incidence of tuberculosis 
was 10 million in 2017 and reported TB mortality was 

2 
1.6 million globally. Pakistan is one of the 30 high 
burden countries for tuberculosis worldwide with 
61% of TB burden in Eastern Mediterranean Region 
of WHO. In Pakistan, 510,000 new cases of TB 
emerge each year and around 15000 cases develop 

1
drug resistant tuberculosis annually.  
In recent years, prevalence of drug-resistant TB has 
increased and became a continued public health 
crisis worldwide. There are three forms of drug 
resistant cases of tuberculosis: RR-TB, (Rifampicin 
Resistant-Tuberculosis), MDR-TB (Multidrug 
Resistant-Tuberculosis) and XDR-TB (Extensively 
Drug Resistant-Tuberculosis). According to WHO, 
160684 cases of MDR/RR-TB (Multidrug Resistant/ 
Rifampicin Resistant) were reported in 2017 all over 
the world. Pakistan has fourth highest prevalence of 

2
multidrug resistant TB (MDR-TB) globally.  
Drug resistant tuberculosis is a potentially 
devastating threat to TB control as it gives 
emergence to the strains that cannot be cured by 

3 
standard first line anti-tuberculosis treatment. MDR-
TB cases are resistant to isoniazid and rifampicin. 
After developing resistant to first line therapy, 
patient is treated with prolonged and extensive 
therapy of second line injectable drugs. If patient 
develops resistance to second line injectable drugs 
then it is termed as extensively drug resistant-
tuberculosis (XDR-TB). At this level disease becomes 

3
virtually untreatable.
As treatment success remains low, at 55% globally, 
there is an urgent need to improve the quality of 
diagnosis, treatment and care for people with drug 
resistant tuberculosis. Key reasons for developing 
drug resistance among TB cases are: Delayed 

Progress is being made in diagnostic test 
technologies but still there is need to overcome 
questions related to validation and assessment of 
these technologies to make ideal diagnostic test 

4
available with high sensitivity and specificity levels.   
As previously reliance on passive case finding has not 
helped to stop TB pandemic. So active case finding 
and screening strategies instead of passive case 
finding of infectious cases are also needed to 
eradicate the disease. TB has been declared as global 
epidemic. The UN's first high-level meeting in 2018 
on TB, was given the title as “United to End TB: An 

1
Urgent Global Response to a Global Epidemic” .
TB DOTS (Directly observed treatment, short course) 
has been recommended by WHO since 1994, as a 
strategy to treat TB cases and to get control over its 
prevalence. TB DOTS had five components for 
effective treatment and control of disease as 
following: 

1. S u s t a i n e d  p o l i t i c a l  a n d  f i n a n c i a l  

commitment by the government

2. TB diagnosis with sputum smear microscopy 

3. Standardized short course treatment given 

under direct observation for 6-9 months

4. Uninterrupted and regular supply of anti TB 

drugs

5. Standardized recording and reporting of 
4

disease.
In 1999, WHO launched “TB DOTS-Plus” as a strategy 
to control TB resistance by adding second line drug 
into already adopted DOTS components because 
DOTS did not account for TB resistance cases rather 
caused MDR-TB when treatment was repeated 
among untreated cases for prolonged duration. 

diagnosis, unsupervised treatment, inappropriate 
drug regimens, lack of social support in the 
communities and lack of timely follow-ups. To close 
these gaps, much work is required for: drug 
susceptibility testing among diagnosed cases of TB, 
reducing under-diagnosis of TB cases, improving 
access and supervised continuous treatment, 
designing new diagnostics, new medicines and 
treatment regimens with higher efficacy and better 

2
safety.  



DOTS is the role of treatment supporter. Treatment 
supporter ensures that patient has taken right drugs 
in appropriate doses and enters its record in patient's 
treatment card. In stop TB strategy, patient 
supervision and support to complete treatment 
course without skipping any dose is the cornerstone 
of DOTS for achieving TB control with maximum 

5
treatment success rate globally.

REFERENCES
1. 	 Global Tuberculosis control report: World Health 

Organization; 2018.
2. 	 Walzl G, McNerney R, du Plessis N, Bates M, McHugh TD, 

Chegou NN, et al. Tuberculosis: advances and challenges in 
development of new diagnostics and biomarkers. 2018; 
18(7): e199–210. Available from: http://dx.doi.org/ 
10.1016/S1473-3099(18)30111-7

3. 	 Gandhi NR, Nunn P, Dheda K, Schaaf HS, Zignol M, van 
Soolingen D, et al. Multidrug-resistant and extensively drug-
resistant tuberculosis: a threat to global control of 
tuberculosis. 2010; 375(9728): 1830–43. Available from: 
http://dx.doi.org/10.1016/S0140-6736(10)60410-2

4. 	 Raviglione MC, Uplekar MW. WHO's new Stop TB Strategy. 
2006; 367(9514): 952–5.

5. 	 Fa M, Le C, Dacombe R, Mkopi A, Sinclair D. Interventions to 
increase tuberculosis case detection at primary healthcare 
or community-level services ( Review ). 2017; (11). 

DOTS-Plus ended in 2006 due to resource constraints 
and subsequently WHO decided to expand TB DOTS 
again, by redefining the TB DOTS with focus on TB 
diagnosis, treatment and care of patients. The global 
plan to stop TB by 2015 included TB control targets 
that were covered under the targets of Millennium 

 1
development goals (MDGs).  
After 2015, another global plan to end TB by 2020 
was “WHO End TB strategy” which emphasized on a 
need of paradigm shift for radical change in TB 
survillenc and to set targets to be met in coming 
years. The focus of End TB strategy is to improve tools 
for case finding among high risk population, 
treatment of new cases and detection of drug 
resistance among TB cases. It is also to be 
understood that only improving diagnostic 
technologies will not reduce disease transmission 
unless early detection of infection and treatment of 

1
cases will not be carried out.
DOTS are still considered effective for treatment of 
new cases of TB and prevention of RR-TB/MDR-TB. 
Failure to adapt DOTS in its true spirit is the leading 
cause of increased drug resistance cases of 
tuberculosis globally. The most important part of TB 

55