Classification of fungal diseases

Principles of systematization

To properly divide all existing fungal infections into clear categories, specialists use three fundamental factors.

First, pathogen localization is evaluated — that is, the specific site in the body where the microorganism has established itself and is multiplying. Second, the nature of primary colonization is taken into account, showing exactly how the fungus attaches to the host tissues. Third, the presence of toxic-allergic properties plays a crucial role, determining whether the microorganism is capable of producing toxins or triggering hypersensitivity reactions.

Infectious lesions of the skin and appendages

The first two classification groups are associated with the external integument of the body. The severity here depends directly on how deeply the pathogen has penetrated.

1. Superficial mycoses. This group is also referred to as keratomycoses. This is the mildest form of invasion, where the destructive process is strictly limited. The pathogen does not penetrate deeply, multiplying exclusively in the uppermost layers of the skin and affecting only the hair cuticle.
2. Epidermophytoses. Another name for this category is dermatomycoses. Here, a much deeper involvement of structures is observed. The pathological process encompasses the entire epidermis and actively involves the skin and hair in the infectious process.

Deep invasions

Once the protective barriers are breached, fungal agents are capable of penetrating deeper structures of the organism, causing severe lesions.

• Subcutaneous mycoses (subcutaneous). In this scenario, the invasion does not stop at the epidermal level. The pathogen spreads deeper, involving the dermis, subcutaneous adipose tissue, and in some cases reaching the fascia and muscle tissue.
• Systemic mycoses (deep). This is the most serious form of the infectious process proper. The pathogen spreads throughout the body, directly targeting internal organs and various deep tissues of the macroorganism.

Special forms of interaction

In addition to classical infections, three specific groups of conditions are distinguished, depending on immune status or the toxic properties of fungi.

• Opportunistic mycoses. These diseases develop exclusively against the background of a marked decline in the patient's immune defense. They are caused by opportunistic microorganisms that are normally harmless to a healthy person.
• Fungal allergies. They manifest as various hypersensitivity reactions of the macroorganism to fungal antigens. Depending on the localization of the reaction, they may occur in the form of pneumoallergies or dermoallergies.
• Mycotoxicoses. A unique group of pathologies in which the infectious process is completely absent. The disease is a classic food poisoning caused by the ingestion of toxins produced by fungi outside the human body.

Class and exam questions

What else to study on this topic

• Mechanisms of primary tissue colonization
• Specifics of opportunistic infections in immunocompromised states
• Differences between pneumoallergies and dermoallergies
• The nature of toxic-allergic properties of pathogens

Other topics in the section "Superficial mycoses (pityriasis versicolor, piedra, etc.)"

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