Yeast infection

What is a yeast infection?

An infection with a yeast is a clinical picture that is caused by fungi (yeasts). The mushrooms can generally be assigned to the mushrooms. The fungi, in turn, form a core group of microbiology alongside bacteria, viruses, protozoa and algae. The yeast fungi (sprout fungi) are the most important species, the non-pathogenic (apathogenic) Saccharomyces or baker's or wine yeast fungus.

Furthermore, the facultatively pathogenic (pathogenic) species Candida, as well as Trichosporon and Cryptococcus can be distinguished. In medicine, facultative pathogens are disease-causing microorganisms that can cause an acute clinical picture, but do not do so in all cases. This in turn means that you do not have to automatically develop acute symptoms when infected with a yeast, but that asymptomatic death is also possible.

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  • Mushrooms
  • Yeast in the mouth

How is a yeast infection noticeable?

Certain symptoms can also occur with a yeast infection, which are included in the differential diagnostic procedure.


When the pathogen manifests on the skin, it can lead to reddening, flaking, inflammation, itching and oozing.

Read more on the topic: Yeast fungi on the skin

Mucous membrane

If the mucous membrane is affected, for example in the mouth and throat area, the appearance of a thrush appears. Here, the examining doctor notices raised, swollen and reddened areas of the mucous membrane, which are often covered with whitish coatings.

You might also be interested in the topic: Skin fungus

Genital fungus

The yeast often also affects the vagina, where it finds an ideal environment (vaginal fungus). This local manifestation is particularly noticeable through severe burning and itching. A creamy discharge and a noticeable odor in the vaginal genital area are also not uncommon. Of course, the vaginal fungus can also be transmitted to the male sex through sexual intercourse. Cardinal symptoms are an inflammatory reaction of the foreskin and the glans. Across the sexes, a genital fungus can lead to severe pain when urinating and sexual intercourse.

Read more on the topic: Yeast in the vagina

Internal organs

Gastrointestinal complaints such as diarrhea or abdominal pain, gas and heartburn can be signs of an intestinal fungal infection. The yeast pathogens are often absorbed via the gastrointestinal tract with the oral cavity as the primary site and through the genital tract.

Read more on the subject here: Yeast in the intestine

Another typical place for a yeast infestation is the nails. A manifestation on the skin and mucous membrane in connection with the symptoms described above in the area of ​​the body cavity openings should at least make the doctor think of a possible yeast infection. Other unspecific signs of an infectious event can also be a general decline in performance, fatigue and headaches.

How is a yeast infection treated?

Several principles can also be followed in the therapeutic approach to yeast infections. First, a trial with a specific antifungal agent can be initiated. Antimycotics (anti = against, mycotic = fungus) intervene in different metabolic processes of fungi and consequently inhibit them. This group of drugs can be administered either locally or systemically. Antifungal creams and ointments are used locally as part of conservative therapy. If these do not show the desired effects, you should switch to a more intensive systemic form of therapy.

Antimycotics are also differentiated according to their mechanism of action. On the one hand, they can form pores at specific points on the plasma membrane of fungi. Examples include nystatin and amphotericin B. Others (for example clotrimazole, itraconazole) inhibit the synthesis of ergosterol. Cell wall or RNA synthesis can also be inhibited. When choosing the right antifungal agent, factors such as the location and severity of the infection play a role.

On the side of the drug, a decision is made based on the above-mentioned mechanisms of action and the possible side effects. Side effects can include fever and headache, nausea and vomiting, stomach and intestinal discomfort. An existing pregnancy or the presence of severe liver disease are contraindicated for therapy with systemically active antimycotics.

You might also be interested in the topic: Treatment of vaginal thrush and anti-fungal medication

Duration and prognosis of a yeast infection

Depending on the localization, the prognosis and the duration of the disease and treatment are different.

Vaginal fungus

A vaginal fungus is usually a disease with a favorable prognosis. However, there are protracted courses with persistent symptoms for various reasons. The antifungal therapy should not be stopped early and should be carried out continuously. Refraining from sexual intercourse or protected sexual intercourse (with condoms) also have a preventive effect.

About 5-10% of all vaginal mycoses develop into protracted, persistent symptoms. If the sexual partner also suffers from a genital fungus (fungus on the penis), it must inevitably be treated with an antifungal agent. In the extreme case of a strong immune deficiency, a vaginal fungus can also spread systemically into the organ systems and trigger stubborn infections.

Read more on the topic: How contagious are yeasts?

Intestinal fungal infection

The intestinal fungus is usually a well treatable clinical picture with a favorable prognosis. With a productive use of the antimycotic therapy you can get an intestinal fungus infection under control within a few days to weeks. As with all other yeast infection manifestations, the healing success depends of course on the current state of performance of the immune system.

Especially in the case of intestinal fungal infections, a diet is used in addition to systemic drug therapy. Food containing sugar, wheat flour and alcohol should be avoided for about 4 weeks. The consumption of vegetables and whole grain products is intensified as part of this therapy principle. In some cases, this combination leads to quick relief of the symptoms. A few principles play a decisive role, especially preventive. Well-developed hygiene, a balanced diet and avoidance of nutrient deficiencies (especially zinc) have shown a preventive value.

Fungal infection in the mouth

If the infection with a yeast affects the lining of the mouth and throat, it is called oral thrush. This manifests itself on the lips, the tongue or the roof of the mouth. Here, too, a good prognostic outcome of the disease has been shown. Consistent therapy, however, also represents the essential importance of the therapy regime here.

There are a number of things you can do to prevent oral thrush. In children, pacifiers, teats and toys should be cleaned regularly. Good dental hygiene should also be followed. In elderly immunocompromised patients, prophylactic administration of antimycotics can be sought. Dental prostheses or all other foreign materials in the mouth area should also be cared for with great hygiene.

Read more on the topic: Oral thrush

Fungal infection on the glans

As in women, yeast infections in men (penis fungus with candida balanitis) respond well to antifungal therapy. Both women and men are usually the same pathogens, which is why they can be treated identically. Even if it is a very unpleasant clinical picture, the penis fungus heals within a few days with early and consistent therapy.

Basically, all manifestations of the fungal infection can cause relapses, which should be given another antimycotic therapy as soon as possible.


Infection with the best-known Candida species is primarily an infection with Candida albicans. This is by far the most common species worldwide. As normal inhabitants, they colonize the skin and in most cases also the mucous membranes of the human body.In this state, they do not pose a direct threat to the body, but rather fulfill an important function in a complex system of bacteria and fungi. If the microbial milieu on the skin and mucous membrane is out of balance (for example due to an immune deficiency), Candida albicans can transform itself into a hyphae and migrate into deeper tissues. Once there, an infectious process often unfolds. If this can be limited superficially and locally, it is called candidosis.

If manifested on the skin and mucous membrane, the familiar picture of mucocutaneous candidiasis or thrush can appear. If the immune system is severely weakened, the pathogen can spread locally in the blood and organ systems and ultimately lead to systemic mycosis.

The lesser known species Cryptococcus can be divided into the pathogens Cryptococcus neoformans and Cryptococcus gattii. The associated clinical picture is called cryptococcosis. The pathogens mentioned are usually found on grass and other plants. In the case of the pathogen Cryptococcus gattii in particular, it can be said that it is primarily found in tropical regions. If the pathogens get into the gastrointestinal tract after being absorbed by the feeding of birds (especially pigeons), they can initially multiply in a suitable environment. Humans become infected with the pathogens mainly through the excrement excreted by the birds or the contaminated dust from excretion products of the birds. In the vast majority of cases, a cryptococcus infection first affects the lungs. In the case of massive immunodeficiency, manifestations of the brain or meninges can also occur (meningoencephalitis). A massive immune deficiency occurs especially in autoimmune diseases such as AIDS.

How does the doctor recognize a yeast infection?

In the case of infections caused by the different types of yeast, different diagnostic methods are used.

In the case of an infection with Candida albicans, a microscopic examination can be considered as the initial diagnostic agent. The level of examination can be improved with the help of optical brighteners or silver coloring (Grocott). Nowadays, MALDI-TOF mass spectrometry is also increasingly used after previous culture. With this method, the proteins contained in the bacteria are separated and differentiated by a precise ion bombardment. It is also possible to examine mannan or glucan antigens, which can be specifically assigned to the Candida species. This diagnostic is usually obtained from a sample in the blood serum or from a bronchoalveolar lavage (BAL).

The diagnostic phase for a Cryptococcus infection is very similar. Fine methods such as microscopy, PCR or, as already mentioned above, antigen detection from the patient's serum are used here.