World Tuberculosis Day 2023: Pulmonologist Explains Drug-Resistant Tuberculosis & Its Treatment

On March 24, 1882, Dr Robert Kochs first discovered the bacteria that causes tuberculosis (TB). Since then, March 24 has been recognised as World Tuberculosis Day, with the slogan "YES! We can end TB" as its subject.

The air is a medium for the airborne transmission of the bacteria that cause tuberculosis (TB). Despite the fact that TB frequently impacts the lungs, it can also damage other organs like the brain, kidneys, or vertebrae. TB is usually curable and manageable, but if it is not correctly treated, a person may even lose their life. Drug-resistant TB results from the germs becoming immune to the drugs used to treat TB. The medication is no longer effective at killing TB bacteria as a consequence. In this article, Dr Ugandhar Bhattu. C, Consultant Interventional Pulmonologist, Yashoda Hospitals, Hyderabad, explains drug-resistant TB and its treatment.

What is Drug-Resistant Tuberculosis

Drug-resistant TB (DR-TB) is a form of tuberculosis that cannot be treated with first-line anti-tuberculosis drugs like Isoniazid (INH) and Rifampicin because Mycobacterium tuberculosis (MTB) is immune to them.

Also Read: Tuberculosis: Importance Of Early Diagnosis And Treatment

DR-TB is transmitted using the same techniques as drug-susceptible TB. TB is spread from one individual to another through the air. So, when a person with TB disease of the lungs or throat coughs, sneezes, speaks, or sings, the TB bacteria are released into the air. Those nearby could inhale these microorganisms and acquire the infection.

Causes of Drug-Resistant Tuberculosis

When the medications used to treat TB are improperly utilised or maintained, drug-resistant TB may develop. Examples of misuse or poor management of TB drugs include the following.

• Individuals don't always finish the entire TB treatment regimen.
• The wrong course of therapy is advised by medical experts.
• There are no successful treatments in the form of medicines.
• The standard of drugs is low.
• DR-TB is more typical among the following, who
• Do not get diagnosed with TB with sputum, culture & sensitivity. 
• Do not routinely take their TB medications.
• Take only some of their TB medications.
• Come from regions of the world where drug-resistant TB is frequent and relapse after receiving treatment for TB disease have interacted with a person who has drug-resistant tuberculosis.

Symptoms of Drug-Resistant Tuberculosis

Following are the symptoms of DR-TB.

• Chronic cough for more than two weeks duration.
• Fever 
• Loss of appetite
• Loss of weight
• Not responding to antibiotics.
• The patient may have an old history of TB.
• May be treated or not treated completely for the infection.

Treatment of Drug-Resistant Tuberculosis

Individually Drug Resistant TB (such as INH Resistant): This kind of DR-TB will be treated for six to nine months using Levofloxacin, Rifampicin, Pylizinamide, and Ethambutol. Rifampicin and INH both are resistant and hence not used in the Multidrug-resistant TB (MDR-TB) treatment regimen.

Short Oral Bedaquiline Regimen: You should have nine to 11 months of treatment, which is comprised of four to six months plus five months. 

Long Oral Bedaquiline regimen: In this regimen, you need to be treated for 18 to 20 months. 

Important Things To Note

To learn about the negative effects of second-line ATT medications, thorough monitoring and frequent blood tests are necessary.

MDR therapy must be avoided throughout any stage of pregnancy due to the high risk of teratogenicity (developmental defects on the foetus) it poses. Women of reproductive age have all been given the MDR-TB diagnosis. Pregnancy must be ruled out before beginning these treatments.

Diarrhoea, vomiting, rashes, photosensitivity, seizures, renal toxicity, liver damage, and mental problems are the most frequent side effects of these medications. 

The government provides free diagnostic services at the DOTS centre, including TrueNat, line probe assay on sputum, confirmation by cultures, identification of categories, and the beginning of various regimens according to the patient.

Take Home Message

MDR-TB showcases symptoms of cough and fever in patients with a previous history of TB and bacteriologically confirmed with culture and sensitivity of sputum. It is a dreaded disease to treat and has a poor prognosis. Bedaquiline and Delamanide are new drugs added to existing MDR-TB treatment.

Image Credits: freepik