How many types of skin ringworm are there and what are they? What are the symptoms?

Dermatophyte is a common disease in our lives. This disease often brings great distress to patients. So what are the types of dermatophyte? What are the symptoms?

1. Tinea capitis

This disease is a superficial fungal disease that occurs on the skin and hair of the head. In my country, tinea capitis is basically divided into four types, namely yellow tinea, white tinea, black dot tinea, and pustular tinea.

(I) Yellow ringworm

The pathogen of yellow ringworm is Trichophyton and its Mongolian variant. This disease is called fat sore in traditional Chinese medicine, commonly known as "bald sore" in my country, and "bald head" in the south. It is mainly prevalent in rural areas, more common in children aged 7 to 13 years old, with a male to female ratio of 9:1, but it can also occur in adults and adolescents.

(ii) White ringworm

In my country, ringworm is mainly caused by infection with Microsporum ferrugineum. It often causes epidemics in town nurseries or primary schools. Almost all of them occur in childhood. Illuminating the lesion with filtered ultraviolet light will reveal bright green fluorescence. Early fungal microscopic examination of dandruff is often positive.

(III) Black spot ringworm

The causative agent of this disease is Trichophyton rubrum or Trichophyton tonsurans. It mainly affects children, and its incidence rate is second only to ringworm white and ringworm yellow. The disease does not show fluorescence when tested with filtered ultraviolet light. Microscopic examination of the extracted hairs showed that 80% were Trichophyton rubrum and 20% were Trichophyton tonsurans.

(IV) Keratosis pilaris

Kerion is caused by infection with zoophilic fungi such as Microsporum gypseum or Microsporum capsici.

2. Tinea corporis

Except for the head, palms, soles, groin, private parts and nails, the skin diseases caused by dermatophytes infecting the smooth skin on the human body are collectively called tinea corporis. Also known as tinea corporis or ringworm. The common pathogens of this disease are Trichophyton rubrum, Trichophyton gypseum, Epidermophyton floccosum, Trichophyton rubrum and the pathogens of tinea capitis mentioned above.

Tinea corporis is more common in children and secondly in adolescents. Patients with tinea corporis feel severe itching, which may lead to bacterial infection after scratching. Scraping the scales around the lesion for microscopic examination may reveal hyphae or spores.

3. Tinea cruris (Tineacruris)

This disease can be regarded as a special type of tinea corporis occurring on the inner side of the upper thigh. The most common pathogen is Epidermophyton floccosum, but other dermatophytes can also cause the disease. Compared with tinea corporis, this disease has the following differences: first, the lesions of tinea cruris are rarely round or oval in shape, but mostly irregular or arc-shaped; second, the skin lesions of tinea cruris often manifest as lichenification or acute and subacute eczematous changes; third, tinea cruris is more likely to be complicated by bacterial infection; fourth, the itching of tinea cruris is more severe.

4. Tinea pedis

Tinea pedis is the most common superficial fungal disease caused by pathogenic fungi infecting the foot. It is commonly known as athlete's foot or dampness in my country. The main pathogens of this disease are Trichophyton rubrum, Epidermophyton floccosum, Trichophyton gypseum and Trichophyton rosea. In addition, cases caused by Candida albicans have also been reported frequently. Close skin contact with moisture and lack of ventilation leads to poor sweat evaporation. Tinea pedis lesions are generally divided into the following three types:

(I) Blister type: Deep blisters ranging in size from needle tips to millet grains can be seen between the toes and soles of the feet. The blister walls are thick and are sparsely or densely distributed. Adjacent rashes may fuse to form larger blisters. The blister fluid is naturally absorbed and turns into scales after drying.

(ii) Interdigital erosion type: It usually occurs between the toes, and the affected area is moist and sweaty. The rash initially appears as immersion, and due to itching or rubbing, the epidermis is damaged, and eventually turns into erosion, flushing and moistness. It may be accompanied by exudate, which often emits an unpleasant odor.

(III) Squamous and keratotic type: quite common, prone to invading the sole, sides, between the toes and heels. The skin lesions appear as scales, thickened keratin, roughness and hardening, with occasional cracks. The disease is particularly severe in winter. The patient suffers from severe itching, especially in the blister type and interdigital erosion type. The incidence of tinea pedis is related to the season. It is often lighter in winter and heavier in summer.

5. Tinea manuum (Tineamauns)

Tinea manuum is a superficial fungal disease that occurs on the palm of the hand, and its symptoms are similar to the "goose palm wind" in traditional Chinese medicine. It can be primary, but most of the time it is transmitted from tinea pedis itself. The pathogen is the same as that of tinea pedis, and the clinical manifestations are similar to those of tinea pedis.

7. Tinea versicolor

Because tinea versicolor presents alternating purple and white spots, traditional Chinese medicine named it "purple and white pityriasis versicolor". Due to the prevalence of sweating rashes in summer, it is also commonly known as pityriasis versicolor. The disease is caused by tinea versicolor fungi that parasitizes on the stratum corneum of the epidermis. Tinea versicolor usually occurs on the neck, chest and back. There are generally no subjective symptoms, and occasionally there is a slight itchy feeling when sweating.