Mycoplasma hominis

As Mycoplasma hominis is the name of a bacterial species that inhabits the human intestine as a commensal. The germ can sometimes cause urinary tract infections.

What is mycoplasma hominis?

Mycoplasma hominis is a member of the Mycoplasmataceae family. The mycoplasma or mycoplasma belong to the cell wallless bacteria and are related to the ureaplasma.

Mycoplasma hominis is the only reservoir used by humans. The type of bacteria may include a. in its intestinal flora. Since there is a proximity to the urogenital area, the pathogen triggers urinary tract diseases in some people.

The mycoplasma belong to the class of the Mollicutes (soft skin) and have a very small genome. Because of this, they are also interesting for genetics. If a disease occurs through Mycoplasma hominis or other mycoplasma, medicine is called a mycoplasma infection.

Occurrence, Distribution & Properties

Mycoplasmas are among the smallest types of bacteria. Mycoplasma hominis only reaches a size of 0.1 to 0.6 µm. The bacterium is endowed with both DNA and RNA. Although the mycoplasmas are considered to be extremely flexible, they have only a low osmotic resistance. Therefore, Mycoplasma hominis cannot be marked with a Gram stain. For this reason, the administration of beta-lactam antibiotics is unsuccessful in an infection with Mycoplasma hominis. They only have an effect on those bacteria from which a cell wall is built up that has a murein layer. The enzyme lysozyme, which occurs in the endosome, is also ineffective.

One of the typical characteristics of Mycoplasma hominis is that the bacterium cannot synthesize cholesterol, which is due to its altered metabolism. For this reason, the bacterial species needs a host cell in order to be able to grow. Furthermore, Mycoplasma hominis is equipped with special surface molecules. However, these are not pili. Nevertheless, as cytoadhesins, they allow attachment to the epithelium of the intestine.

Mycoplasma hominis is common all over the world. It is estimated that the Mollicutes have existed for 65 million years and have very efficient survival mechanisms. Since they only reach a tiny size, have no cell wall and are very simply equipped and malleable, they are considered to be perfectly equipped for a parasite existence. In doing so, they are able to adhere tightly to the membranes of their host cells. If necessary, they can also perform gliding movements and achieve mobility.

Mycoplasma hominis lives as commensals in the intestines and urogenital tracts of humans. In contrast to a regular parasite, a commensal feeds on the food residues of the host body. As a rule, however, the bacterium does not cause damage to the organism, although it uses the human body in its favor. If the person's immune system functions properly, Mycoplasma hominis cannot develop any pathogenic effects and is classified as non-pathogenic. Some of the mycoplasma can also be found on the genital mucosa.

Illnesses & ailments

Under certain circumstances, Mycoplasma hominis can develop disease-causing effects. This applies primarily to people who suffer from a local or general weakening of their immune system. This arises, for example, from treatment with antibiotic drugs. The same applies to surgical interventions, the birth process or cancer.

Local inflammation is sometimes triggered by Mycoplasma hominis. These include above all urethritis (inflammation of the urethra), inflammation of the renal pelvis, the uterus or vagina and the male prostate (prostate). In addition, progressive infections are possible, with people suffering from general symptoms or fever.

Furthermore, the mycoplasma can be transmitted through sexual intercourse. For this reason, mycoplasma infections are counted among the sexually transmitted diseases. However, it is controversial whether the bacteria are also responsible for infertility and miscarriages. The number of mycoplasmas on the genital mucosa depends on how sexually active the person is and how many sexual partners they have. For example, larger amounts of mycoplasma are found in people who frequently have sexual intercourse with alternating partners. In principle, antibodies against mycoplasma can be detected in the blood of around 95 percent of all middle-aged people.

The complaints caused by Mycoplasma hominis are often unspecific and only slightly pronounced. They also depend on the part of the body where the inflammation occurs. Most people experience a burning sensation when urinating, pain in the kidneys, or yellowish discharge.

It is not always easy to clarify the cause of an infection with Mycoplasma hominis, as the bacterium is also found in healthy people. It is possible to cultivate the germ on a special nutrient medium. Urine, swabs from the vagina or urethra of the woman and prostate secretion or ejaculate from the man can be used as test material.

Treatment of infection with Mycoplasma hominis is with antibiotics. However, not all agents of this type are suitable for therapy because the mycoplasmas do not have a cell wall. For example, the pathogens are resistant to penicillin. Instead, antibiotics such as erythromycin are used, which have different mechanisms of action.