The chemotherapy regimens in pulmonary tuberculosis: stages, phases, consequences

Tuberculosis is the cause of a large number of deaths caused by a single microorganism (M. tuberculosis). The main problem in chemotherapy of the diseases are resistant to drugs strains of bacteria.

Under the regime of chemotherapy understand the optimal combination of drugs to treat TB, their doses, route of administration, rate of application and duration.

In this article we consider the features of the modes and principles of their selection.

Definition of the disease

Tuberculosis is one of the most serious diseases. It has been known since Ancient Greece, where it was called phtisis, which translates as "exhaustion".

Science has worked for many years on drugs, which would allow to prevent and treat tuberculosis.

Tuberculosis is the most infectious disease that is caused by M. tuberculosis (the tubercle Bacillus) and is accompanied by lung damage.

The bacteria that cause TB spread through the air when a sick person coughs, sneezes or coughing up phlegm. In order to become infected person needs to inhale only a few of these germs. But it should be remembered that transmission of infection possible by contact-household.

Tuberculosis affects not only the lungs, but other organs and tissues, e.g. eyes, bones, skin, urinary system, intestines.

What is the effect of the tubercle Bacillus on the body

There are two forms of the disease:

1. Open form. Mycobacteria present in the sputum or other discharge.
2. Closed form. Bacilli in the discharge not determined, the patient can not infect other people.

Also, TB can be primary and secondary.

Primary is characterized by the fact that it occurs as soon as the blood was the causative agent. It often affects children up to five years. In this case, the TB runs hard with very pronounced symptoms, however, patients are not dangerous to healthy people. In the lung granuloma is formed small in size. In some cases, tuberculous granuloma, it can self-heal. And sometimes it increases and within it a cavity (cavity) filled with blood. Her mycobacteria from the bloodstream are carried throughout the body.

Secondary tuberculosis occurs when the ill person was infected with another type of tuberculous mycobacteria, and got sick again, or if, when the worsening of the disease. The patient is very contagious to others. It needs to be hospitalized and treated with combined antibiotics.

Symptoms of tuberculosis:

1. Change the appearance of a person. The face is haggard and pale, the facial features become sharper, the cheeks fall and covered with an unnatural glow, his eyes an unhealthy Shine. There is a rapid weight loss.
2. Temperature. The main symptom of tuberculosis is low-grade fever that lasts for one month or more. In the evening the temperature may rise to thirty-eight degrees and be accompanied by chills. Above thirty-nine degrees the temperature rises in the later stages, when there is a lot of inflammation.
3. Cough. It is present almost constantly. In the initial stages he cough is dry and paroxysmal. When formed cavity and lungs exudate accumulates, it produces large amounts of phlegm. The cough passes into the wet.
4. The hemoptysis. This symptom may be indicative of infiltrative tuberculosis. In this case, need urgent surgical care.
5. Chest pain. This symptom appears in acute and chronic stages of tuberculosis.

Tuberculosis is dangerous complication such as pulmonary hemorrhage. It can also cause spontaneous pneumothorax and pulmonary insufficiency.

What is the chemotherapy regimen

A chemotherapy regimen is a combination of drugs to treat TB, their doses, route of administration, rate of application and duration. Under the chemotherapy of tuberculosis refers to the specific treatment that aims to destroy the bacteria or inhibit their reproduction.

Purposes

The main objectives of chemotherapy are:

• Prevention of selection of drug-resistant mycobacteria.
• The achievement of the earlier bazillionare sputum.
• Complete cure from TB.

This goal can be achieved only if simultaneously assign multiple drugs to which bacilli are sensitive.

Phases

The Ministry of health of the Russian Federation recommends a course of chemotherapy in two phases: intensive and continuation therapy. The tasks of these phases are different.

The first phase aims to eliminate symptoms of tuberculosis. It includes:

1. The greatest impact on the population of mycobacteria in order to cease bacterial excretion and prevent the development of resistance of bacteria to drugs.
2. The decrease in infiltrative and destructive changes in organs.

The second phase is the continuation phase of therapy. It is necessary to implement multiple tasks:

1. Suppression of persistent populations of bacilli.
2. The provision of further reducing the inflammatory changes and involution of tubercular process.
3. Recovery functionality.

That includes

Chemotherapy for the treatment of tuberculosis includes:

1. A combination of selected drugs.
2. The terms of their admission.
3. The timing and content of monitoring surveys.
4. Organizational forms of chemotherapy, which are determined on the basis of the group, which includes people with tuberculosis.

Modes

The chemotherapy regimens are standard and individual.

Individual mode includes such a combination of drugs, which are preserved drug sensitivity of the mycobacteria, after receiving the data of microbiological research.

Standard mode includes a combination of the most effective drugs considering the fact that the data determining drug susceptibility of mycobacteria known only after two or three months.

Currently, there are four standard mode.

Initial

The first mode is assigned to new patients. Intensive phase of treatment lasts two to three months using the four main drugs: Isoniazid, Rifampicin, Pyrazinamide, Ethambutol or Streptomycin.

The total duration of the basic treatment lasts six to seven months.

Second

The second mode is assigned for patients with relapse of tuberculosis and patients receiving inadequate chemotherapy more than one month.

Within two months of being used five main drugs: Isoniazid, Rifampicin, Pyrazinamide, Ethambutol and Streptomycin. And within a month four: Isoniazid, Rifampicin, Pyrazinamide and Ethambutol.

The total duration of treatment is eight to nine months.

The Second B

This mode is used for the treatment of patients with a high risk of development of drug resistance of mycobacteria.

Within two to three months apply to such drugs as Isoniazid, Rifampicin, Pyrazinamide, Ethambutol, Kanamycin, Fluoroquinolone.

Third

The third mode is recommended to patients with newly diagnosed small forms of tuberculosis with the absence of isolation of mycobacteria.

The intensive phase lasts two months and includes four drugs: Isoniazid, Rifampicin, Pyrazinamide, Ethambutol.

The total duration of treatment is six to eight months.

Fourth

This mode is assigned to patients who were isolated multidrug-resistant mycobacteria, and in chronic tuberculosis.

Treatment for individual chemotherapy regimens. The intensive phase lasts six months.

Selection of the optimal

Selection of the optimal mode is determined based on the following factors:

1. The nature of the regional drug sensitivity of mycobacteria to the drugs.
2. The infectiousness of a sick person.
3. The prevalence and severity of the disease.
4. Drug resistance of mycobacteria.
5. Dynamics of clinical and functional parameters.
6. The dynamics of the discharge.
7. Involution (resorption) local changes in the lungs.

Choosing the mode you need first to determine the indications for the use of TB drugs and an appropriate regime of chemotherapy. Then select the conditions of chemotherapy (hospital, sanatorium and outpatient conditions).

Professionals need to provide controlled patients receiving the combination of drugs throughout the period of treatment, and arrange follow-up care and periodic examination.

All of this must be decided individually for each patient. The choice of treatment dependspeculiarities of tuberculosis and capabilities of the facility.

If the patient has drug resistance

Resistance is a reduced sensitivity of mycobacteria to the extent that they are able to multiply when exposed to drugs at critical or higher concentration. The stability level is determined by this concentration of drug at which is observed the proliferation of mycobacteria.

For definitions of drug resistance used method of absolute concentrations on dense egg medium of Levenshtein-Jensen medium. M. tuberculosis having resistance to the medicine, capable of multiplying at such content of the drug in the environment that affects sensitive individuals a bacteriostatic or bactericidal effect.

Initial

The initial (primary) drug resistance is characterized by the fact that at the beginning of the examination phase, the strains of bacteria that have a pronounced resistance to one or more anti-TB drugs.

Such resistance occurs in cases where people are infected with mycobacteria that are already resistant to one or more TB drugs.

The frequency of primary drug resistance characterize the epidemiological status of the populations of Mycobacterium tuberculosis.

Acquired

With acquired or secondary resistance strains of bacteria become resistant to the medication during or after the course of chemotherapy. Improperly performed chemotherapy contributes to the emergence of drug-resistant mycobacteria.

Monoresistant

Monoresistance resistance is called the strain's resistance to one of the five main first-line drugs for treatment of tuberculosis.

Multidrug resistant

Polyresistance is a complex combination of resistance to any two drugs or more without simultaneous resistance to Isoniazid and Rifampicin.

Mixed

Combined totals of primary resistance and acquired resistance to determine its prevalence.

Summary

Tuberculosis is a very serious and dangerous disease. It can be transmitted anywhere, because M. tuberculosis can be transmitted as airborne droplets, contact and household way.

For the diagnosis of active TB is microscopic examination of sputum smear, x-ray or culture (sputum).

Treatment of tuberculosis is necessarily performed with multiple drugs. Each drug has different mechanisms of action.