Mycobacterium tuberculosis…the causative agent of Pulmonary Tuberculosis or PTB.

Introduction:

According to the World Health Organization ( WHO ), Pulmonary Tuberculosis or PTB is considered as a major health global concern. And it can be effectively treated in a short course of four months instead of a usual six months course treatment for susceptible pulmonary tuberculosis. The new four months treatment is considered a major novel breakthrough in the management for millions of pulmonary tuberculosis patients worldwide. The short course regimen for PTB patients will increase patient compliance, cost-effective, safe and reduce bacterial resistance.

Global Prevalence Rate of Pulmonary Tuberculosis:

It is estimated that there are 1.4 million deaths globally and 10 million new tuberculosis cases in 2019 as revealed by new statistical data. And its numbers are increasing this current year due to the novel coronavirus pandemic which cause the decrease of health care delivery and shortages of anti-TB medications or drugs to TB patients. Health authorities such as the World Health Organization or WHO set the goal of targeting to lower the case rate by 80% in the year 2030 and 90% in the year 2045 worldwide. In the Philiipines TB affected 2.5 million filipinos, and 1 million filipinos have active TB. And many filipinos don’t have the knowledge that they have TB. The Philippines garnered the 3rd highest prevalence rate globally and is next after South Africa and Lesotho as per World Health Organization ( WHO ) report last March of 2019.

History of Pulmonary Tuberculosis:

Dr. Robert Koch

Pulmonary tuberculosis or PTB is cause by an organism called Mycobacterium tuberculosis a pathogenic bacteria discovered by Dr. Robert Koch in March 24, 1882. The disease is very common in people that belongs to the lower socioeconomic status. And spread easily due to overcrowding of inhabitants living in a small quarters or space.The disease spread by droplet transmission and it can have varied signs and symptoms but commonly it presents with cough with or without bloodstreak/yellowish sputum, weight loss, night sweats and late afternoon fever.

TB vaccination dose given intradermal route to the patient.

Vaccination in the form of Bacilli Calmette-Guerin or BCG is given to children living in places or environment where TB prevalence is high to prevent TB in children, extrapulmonary TB and or tuberculous meningitis but BCG is not 100% protective.

Dr. Laertes B. Amihan do physical examination to an 8 month old girl with on and off cough for more than 3 weeks, late afternoon fever and with multiple lateral neck lymphadenopathies.

Clinical and Laboratory Diagnosis for Pulmonary Tuberculosis:

Patient or patients with Pulmonary Tuberculosis can be diagnose presumptively by clinical presentation of signs and symptoms accompanied with the patient’s medical history. Likewise using a simple patient’s chest X-ray and a confirmation test can be done using bacteriologic test such as Direct Sputum Smear Microscopy ( DSSM ) which is considered as the primary diagnostic test for TB, and TB culture or the WHO approved rapid diagnostic test Xpert MTB/Rif for TB. The above mentioned diagnostic tests are the most common tests performed and is available in private and government run health institution locally and used especially by under develop and developing countries around the globe including the Philippines. The diagnosis of pulmonary tuberculosis must be correlated with the clinical history, radiographic result and other laboratory parameters of the patient/s in order to arrive into a correct diagnosis. There are other more advance and sophisticated test available in other rich nations but its use is not cost effective especially in poor and under-develop countries.

Treatment:

Different types of oral drugs for Pulmonary TB treatment.

A. ) Standard Treament Regimen For Susceptible Pulmonary Tuberculosis: World Health Organization- WHO TB Guidelines .

 

The usual treatment course of susceptible pulmonary tuberculosis is a six months course daily intake which divided into 2 phases, namely an intensive phase 2 months daily chemotherapeutic treatment which uses a four drug combination ( INH or isoniazid, rifampicin, pyrazinamide and ethambutol or 2HRZE ) then followed by a 4 months of daily intake of isoniazid and rifampicin as continuation phase or maintainance treatment but before starting patient treatment, the patient must have baseline pretreatment diagnostics or laboratory tests.

B. ) Study 31/A5349:

Funded by the US-National Institute Of Health ( US-NIH ) and the National Institute Of Allergy and Infectious Diseases ( NIAID ) and the Centers For Disease Control and Prevention ( CDC ) Tuberculosis Trials Consortium ( TBTC ) in collaboration with the AIDS Clinical Trials GROUP ( ACTG ) conducted the largest drug susceptible Tuberculosis disease treatment trial. A Phase 3, open-label trial called Study 31/A5349, it is an international, randomized, controlled clinical trial that involved 2,500 patients with age of 12 and above included 214 HIV positive patients in 34 clinical sites from 13 different countries in Asia, Africa, South America and North America. The results of the novel TB treatment study revealed that a short course of 4 months daily treatment is as effective and safe compared with the existing 6 months standard treatment for susceptible pulmonary tuberculosis disease patients. The study used rifapentine with moxafloxacin plus isoniazid added with pyrazinamide or 2PHZM/2PHM for 8 weeks daily treatment and 9 weeks of daily treatment with rifapentine plus isoniazid added with moxifloxacin. The novel treatment for Susceptible TB has an 88% curing or efficacy rate compared to the standard 6 months regimen treatment for TB which has a 90% curing rate up to 12 months after treatment.

The result of the novel TB treatment Study 31/A5349 was presented today at the 51st Union World Conference On Lung Health which being held virtually from October 20 to 24, 2020. And for comment purposes regarding the fate of the novel TB treatment, the CDC’s Division of Tuberculosis Elimination Director , Philip LoBue and NIAID’s Division of AIDS Director, Carl Dieffenbach are also available for further queries.

Conclusion:

The Study 31/A5349 or the new short course regimen for the treatment of susceptible Pulmonary Tuberculosis ( PTB ) will be a new treatment strategy that can be used by clinician in the near future. The novel short course treatment regimen will increase patient compliance, decrease cost, improve the patient’s quality of life, reduce adverse drug reaction with more convenient to use especially during these times of uncertainties due to CoViD19 pandemic. Thus with the advent and introduction of the new short course 4 months daily treatment for susceptible TB in the physicians armamentarium in fighting against the ancient disease that troubles mankind up to the present time will result to a decrease in the incidence of Pulmonary Tuberculosis ( PTB ) globally in the years to come. Although Pulmonary Tuberculosis is curable but people must lean to the safe side of practicing prevention in order to avoid the disease…remember an old adage… ” An ounce of prevention is better than a pound of cure. “

Keep Safe And Stay Healthy Always!


Laertes B. Amihan MD