What causes Candida albicans?

Candida albicans is actually a pathogenic bacterium among the bacteria, but it cannot be said to be 100% pathogenic, so friends should also have a proper understanding of it. The factors that affect the pathogenicity of Candida albicans are related to many things, such as adhesion, dimorphic morphology, extracellular enzymes, etc. These will affect the pathogenic effect of Candida albicans, so friends should pay more attention.

Pathogenic mechanism

Candida is a conditionally pathogenic bacterium, and its pathogenicity is relative. Whether the disease occurs after invading the human body depends on the level of human immunity and the number and virulence of the infecting bacteria. Under normal circumstances, the Candida albicans that parasitize the human body are in the form of yeast cells and are generally not pathogenic. Under the influence of certain physiological and pathological factors of the body, the environment in the vagina or penis changes, and the body's resistance or immunity is reduced, Candida will multiply in large numbers and develop into hyphae, invading tissues. When it reaches a certain amount, the human body will become ill and cause clinical symptoms. These factors usually include pregnancy, diabetes, oral contraceptives, long-term use of broad-spectrum antibiotics, immunosuppressants and corticosteroids, which reduce the body's immunity, or change the vaginal environment. The glycogen content of women's vaginal epithelial cells increases, the acidity increases, and Candida albicans will multiply and cause Candida infection, such as vaginitis. Therefore, this disease is common in pregnant women, diabetic patients and patients receiving estrogen treatment. This fungus can also cause balanitis.

Factors affecting pathogenicity

The pathogenicity of Candida is related to the following factors: ① Adhesion; Adhesion is proportional to virulence, and Candida albicans has the strongest adhesion among the Candida genus; ② Dimorphic morphology: When infected, Candida albicans often appears in hyphae form. The virulence of the hyphae type is stronger than that of the yeast type; ③ Toxins: polysaccharide toxins on the surface of bacterial cells and another type called "Candida toxin" may be pathogenic factors; ④ Cell surface components; ⑤ Extracellular enzymes: Candida albicans can produce and secrete some enzymes, such as lysophospholipase, phospholipase and extracellular acid protease (CAP). Among them, CAP is the most important. CAP can not only hydrolyze protein, but also hydrolyze keratin and collagen, and has the function of promoting the adhesion of Candida albicans.

Related infections

Candida albicans infection first adheres to the host's epithelial cells, and then forms an infection focus under the action of the Candida albicans pathogenic factors mentioned above. Adhesion to epithelial cells is due to the presence of Candida albicans adhesion receptors on the host cell membrane surface, namely fucose and N-acetylglucosamine; Candida albicans cell walls have a variety of adhesion mediators, among which the more important ones are mannan-protein complex (MP) and chitin. Chitin is a three-dimensional polymer composed of (1-3, 1-6) β-glucan and N-acetylglucose receptors; the cell wall of Candida albicans has adhesion receptors of components such as fibrinogen and fibronectin. These components are widely distributed in the blood vessel walls, inflammation and wound healing sites, and have extremely strong adhesion. After adhering to Candida albicans, they can bridge the adhesion between Candida albicans and host cells, making it easier for Candida albicans to adhere to and invade the host.