Fungal Testing for Skin, Hair & Nails in London

What is Fungal Testing?

Fungal infections are among the most common skin, hair, and nail problems seen in dermatology. They can mimic eczema, psoriasis, or bacterial infections, making accurate diagnosis essential before treatment. At Skinhorizon Clinic, fungal testing is performed under consultant supervision to identify the exact organism responsible.

Our approach combines direct microscopy (looking for hyphae and spores), fungal culture (to identify the species), and, where relevant, Wood’s lamp examination (UV light fluorescence in scalp infections). This ensures that treatment is targeted — whether topical antifungals, oral medication, or combined therapy.

When is it recommended?

Fungal testing is indicated when symptoms suggest infection but diagnosis is uncertain, or before starting systemic antifungals. Typical scenarios include:

• Skin: Itchy, red, ring-shaped rashes (tinea corporis), athlete’s foot, jock itch
• Scalp: Patchy hair loss, scaling, broken hairs, suspected tinea capitis
• Nails: Thickened, discoloured, brittle nails suggesting onychomycosis
• Persistent rashes: Eczema or psoriasis-like patches not responding to steroids
• Recurrent infection: Patients with repeated episodes despite treatment

By confirming the presence and type of fungus, unnecessary treatments can be avoided, and the most effective medication can be prescribed.

How it works

1. Sample collection: Skin scrapings, nail clippings, or plucked hairs are taken from the affected site.
2. Direct microscopy: A potassium hydroxide (KOH) preparation is examined under the microscope for fungal elements.
3. Culture: Samples are sent to the lab where the fungus is grown to identify the exact species.
4. Wood’s lamp: For scalp infections, UV light may reveal fluorescence typical of certain fungi.
5. Interpretation: Consultant explains results and tailors treatment accordingly.

What can it help diagnose?

• Tinea corporis (ringworm)
• Tinea pedis (athlete’s foot)
• Tinea cruris (jock itch)
• Tinea capitis (scalp ringworm)
• Onychomycosis (fungal nail infection)
• Pityriasis versicolor

These conditions often overlap with non-fungal dermatoses. Confirming infection avoids inappropriate treatments (such as long-term steroids) and ensures prompt antifungal therapy.

Preparation

• Do not apply topical antifungal creams, ointments, or medicated nail lacquers for 3–5 days before testing.
• Avoid clipping nails too short before nail testing; we require sufficient sample.
• Do not wash affected areas with medicated cleansers just before your appointment.
• Bring a list of any recent antifungal medications (topical or oral).

Safety & limitations

The procedure is safe and painless; sample collection may cause mild temporary discomfort. Limitations include: microscopy may be negative if fungal load is low; culture takes 1–3 weeks; not all fungi fluoresce under Wood’s lamp. Sometimes repeat sampling is required if results are inconclusive.

Results & follow-up

Microscopy results may be available same-day, giving an early indication. Culture confirms the exact species within 1–3 weeks, guiding tailored antifungal therapy. Your consultant will discuss treatment options — including topical agents, oral antifungals, and supportive measures — and arrange follow-up if needed.

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Disclaimer: Diagnostic tests at Skinhorizon are provided only where clinically appropriate and must be interpreted by a qualified healthcare professional. Results alone do not replace a medical diagnosis, and further consultation may be required.