How is tuberculosis treated?
The treatment of tuberculosis also poses a challenge due to the special characteristics of the bacteria (slow growth, relative insensitivity to damaging environmental influences, high mutation rates (alteration of the genetic material)). In the meantime, a treatment exists which has proven to be very effective, but requires a high degree of willingness on the part of the patient. The four standard drugs of tuberculosis treatment are: INH and rifampicin are given as a two-in-one combination for four months in the second phase.
There is a vaccination with mycobacteria, but its effectiveness is controversial and is not currently recommended by the StIKo (Standing Commission on Vaccination). Vaccination is carried out with mycobacteria of the strain BCG, which are less infectious to humans. After the vaccination, a temporary multiplication of the bacteria, which are injected under the skin, occurs.
Later, scarring occurs at the injection site. However, the protective effect is temporary, after several years the effect decreases significantly. Also, a positive result of the tuberculin test is now obtained, because the patient had contact with mycobacteria.
In very rare cases, the vaccination can be the cause of tuberculosis if the patient’s immune system is insufficient. A problem for medicine is the worldwide increasing number of bacteria that are resistant (= insensitive) to the usual drugs. These are bacteria that have had the chance to become resistant to the drugs through improper treatment.
In Germany, this affects about 2% of the bacteria. Much higher rates can be found in some former Eastern Bloc countries. There up to 60% can be affected.
- INH is a drug that inhibits the assembly of the special cell wall of the bacteria and therefore acts quite specifically only against mycobacteria. It is activated by enzymes of the bacteria and thus has comparatively few side effects. However, it does not reach pathogens that are present in human defence cells.
- Rifampicin is a drug that prevents new proteins from being produced in the bacterial cell.
It is also effective against pathogens that are present in the body’s own defence cells.
- Pyrazinamide is only effective against multiplying mycobacteria, which is why it can only be used sensibly in the initial phase of the disease. It works by disrupting the assembly of the cell wall, similar to INH. As a significant side effect, this drug can damage the liver.
- Ethambutol is also an antituberculotic agent that disrupts the assembly of the cell wall. However, it has a different point of attack than INH or pyrazinamide and thus has a useful complementary effect.
