Fungal Infections

Overview

Tinea manuum is a relatively rare dermatophyte infection that affects one or both hands. Although it is less commonly encountered than tinea pedis, which typically affects the feet, tinea manuum can be equally troublesome for those affected.

If left untreated, tinea manuum can lead to complications such as the spread of the infection to other parts of the body, including the nails, feet, or other skin sites. Additionally, the infection can be transmitted to others, particularly in communal or household settings.

Causes and Risk Factors

Tinea manuum is caused by a fungal infection that usually arises through contact with another infected body part, such as the feet (tinea pedis) or the groin (tinea cruris). The infection can also result from direct contact with an individual who has tinea, through casual contact or shared personal items. Exposure to infected animals or soil may likewise lead to tinea manuum, as certain fungi are commonly found in these environments. Transmission can occur through contaminated objects such as towels, gardening tools, or other personal effects.

The fungi responsible for tinea manuum are classified into two main categories. Zoophilic and geophilic dermatophytes are typically transmitted from animals or soil, and include species such as Trichophyton erinacei from hedgehogs, T. verrucosum from cattle, Microsporum canis from cats or dogs, and Nannizzia gypsea from soil. Anthropophilic dermatophytes, which are of human origin, include species such as T. rubrum, T. interdigitale, and Epidermophyton floccosum.

Certain individuals are more susceptible to developing tinea manuum, particularly those who engage in manual labour, experience excessive sweating (hyperhidrosis), or have pre-existing hand dermatitis.

Signs and Symptoms

The symptoms of tinea manuum vary depending on the type of fungus involved. In some cases, an acute inflammatory rash resembling tinea corporis may develop. This form is characterised by a raised border with central clearing, commonly referred to as ringworm, and is more often associated with zoophilic or geophilic fungi.

More commonly, tinea manuum presents as a slowly spreading area of dryness, peeling, and mild itching on the palm of one hand. This form, known as hyperkeratotic tinea, may lead to increased skin markings and often occurs alongside a similar infection in both feet, a phenomenon referred to as "one hand, two-foot syndrome." This pattern is typically caused by anthropophilic fungi.

In some instances, a blistering rash may develop on the edges of the fingers or palm. These blisters often appear in clusters, contain a sticky clear fluid, and may have a peeling edge, frequently accompanied by itching and burning sensations.

Diagnosis

Tinea manuum is primarily diagnosed through clinical examination. Differentiating tinea manuum from other skin conditions, such as hand dermatitis, is essential for effective treatment. Several clinical indicators assist in this distinction. Tinea manuum often affects only one hand, and when both hands are involved, the presentation is typically asymmetrical. Although increased skin markings may be observed in both dermatitis and chronic tinea manuum, the markings in tinea manuum appear white due to surface scaling. The infection may involve both the palm and the dorsum of the hand, and it may be accompanied by a fungal nail infection known as tinea unguium.

The diagnosis is confirmed by microscopy and culture of skin scrapings to detect the presence of dermatophytes.

Treatment Options

For mild cases, topical antifungal agents are generally effective. When the infection is resistant to topical treatments, oral antifungal medications such as terbinafine or itraconazole may be prescribed. Prescription management of antifungal therapies is available at the Centre for Medical and Surgical Dermatology. Early recognition and appropriate treatment can prevent complications and the spread of the infection.

When to Seek Medical Attention

Medical attention should be sought when a suspected fungal infection does not respond to over-the-counter antifungal treatments, when the infection is spreading to other body sites or to the nails, or when there is uncertainty about the diagnosis. A dermatologist can confirm the diagnosis through microscopy and culture and recommend appropriate prescription treatment. A referral from a family physician is typically required to access dermatology services.