Trichophyton rubrum - Clinical Manifestation

Clinical Manifestation of Trichophyton rubrum

Clinical manifestations of Trichophyton rubrum infection include:

1. Tinea pedis

2. Tinea unguium

3. Tinea manuum

4. Tinea cruris

5. Tinea corporis

6. Tinea barbae

7. Folliculitis

8. Extensive granuloma – mostly in immunocompromised (eg Cushing syndrome)

9. Id reaction

Tinea pedis

• tinea pedis, also known as athlete's foot, is a common clinical manifestation of Trichophyton rubrum infection

• infection of the foot, toes, interdigital web spaces

• warmth and moisture produced by the shoes aid in establishing and maintaining infection

• commonly seen in individuals wearing shoes for long hours

• symptoms include itching, scaling, cracking, redness, and in rare cases skin blisters to ulcerative 

• although any area of the foot may be infected, areas between toes are most commonly infected

• chronic cases may result in the moccasin foot in which the entire foot forms white scaly patches

• the moccasin foot is mostly asymptomatic with slightly erythematous plaques on the sole of the foot and is covered by hyperkeratotic scales

• can be divided into four categories -

  * chronic interdigital

  * plantar (moccasin foot)

  * acute ulcerative

  * vesiculobullous

Chronic interdigital

• most common

• occurs between toes

• syndromes include maceration, fissuring erythema, scaling in toe webs

• mostly found between the fourth and fifth toes

Plantar (moccasin foot)

• also known as a moccasin foot or hyperkeratotic

• occurs on the sole of the foot i.e. plantar and lateral surfaces

• associated with scaling or hyperkeratosis

Acute ulcerative

• usually affects the soles of the feet

• associated with maceration, denudation, oozing (pus) of the skin

• macerated lesions with scaly borders

Vesiculobullous

• less common mucocutaneous disease

• characterized by vesicles (less than 5-10mm), bullae (blisters) (larger than 5-10mm) formation

• these vesicles and bullae are fluid-filled lesions

• occurs near the instep and adjacent plantar surface

• pustules, which are sometimes formed, are small with clear vesicles

Complications of tinea pedis

In chronic cases, the skin may crack leading to bacterial skin infection and inflammation of the lymphatic vessels (lymphangitis, lymphadenitis). Trichophyton rubrum may also spread to infect the toenails resulting in a condition known as onychomycosis.

If the host develops a scratch reflex, it may lead to self-inflicted excoriations, and if not immediately washed, it may spread to other body parts/people or even infect nails.

Tinea unguium

• Trichophyton rubrum is one of the causative agents of tinea unguium

• also known as Distal subungual onychomycosis

• fungal infection of the nail (toenail or fingernail)

• invades the nail bed and underside of the nail plate

• symptoms include white, black, green, or yellow nail discoloration, thickening of the nail, separation of the nail from the nail bed

• in chronic cases, nails may become brittle with pieces or whole nails breaking off

• in untreated cases, the skin underneath and around the nail can become inflamed and painful

• no pain or other bodily symptoms unless the disease is severe

• does not necessarily require treatment but oral antifungal medicine is effective (associated with liver problems)

Complications of tinea unguium

The complication of tinea unguium, caused by Trichophyton rubrum, is cellulitis.

Tinea manuum

• tinea manuum, caused by Trichophyton rubrum, is a fungal infection of the hand

• maybe caused by transmission from other fungal infections such as athlete's foot or tinea cruris

• scaling is diffused on the palms or back and each rash looks different

• more prominent palmer creases which appear white in chronic cases

• nails may also be infected

• maybe itchy, look slightly raised with dry flaky thick skin on hand’s palm

• in cases where the back of the hands are infected, reddish circles resembling ringworm are present

• mostly only one hand is affected but Trichophyton rubrum infection may occur on both hands

Tinea cruris

• tinea cruris, caused by Trichophyton rubrum, is also known as jock itch, ringworm of the groin, scrot rot, eczema marginatum, gym itch, crotch itch

• it is a superficial fungal infection of the groin (upper inner thighs), and buttocks which is contagious and occurs predominantly in hot-humid climates

• symptoms include intense itchy red rash with a raised, scaly, and well-defined curved border

• may have some blistering, and weeping, with light colored center

• the rash may appear as flaking, peeling, iridescence, cracking, rippling skin which may appear tan, brown, or reddish in color

• hair follicles may also be involved resulting in papules, nodules, and pustules within the plaque

• in chronic cases, these plaques may reach the scrotum in men, mons pubis, and labia majora in women

• in the case of individuals using steroids for immunosuppression, the penis may also be affected

• the infection may also extend to the anus

Tinea corporis

• tinea corporis, caused by Trichophyton rubrum, is a fungal infection of the body – the arms and legs

• more common on glabrous skin i.e. where there is a lack of hair but may occur on any superficial part of the body

• marked by enlarging raised red rings with a light central area (ringworm_

• symptoms include itching, an elevated rash with scaly touch, hair loss in the infected area

• the skin surrounding the rash appears dry and flaky

Tinea barbae

• tinea barbae, caused by Trichophyton rubrum, is the fungal infection of the hair around the bearded area

• clinically manifests as a cutaneous granulomatous lesion (chronic inflammatory reaction) or  a follicular inflammation

• an important cause of folliculitis

• most common among agricultural workers (animal-to-human transmission)

• human to human transmission is less common

• affected area manifests as a pimple or blister, swelling and redness, and lumpy skin with crusting around hairs in the infected area

• in some cases, can be itchy and painful

• hairs on the infected area are effortless to pull out

Folliculitis

• Trichophyton rubrum infection may result in folliculitis

• may occur anywhere on hair-covered skin

• the condition appears as pimples with white tips

Id reaction

The infected individual becomes hypersensitive to constituents of Trichophyton rubrum and may develop dermatophytids. Dermatophytids are allergic manifestations associated with vesicles of the fingers and elsewhere on the body, especially the hands.

This condition is a response to circulating fungal antigens and the lesions do not contain fungal hyphae. Trichophytin skin test can detect this reaction.