Skin Infection Diagnosis and Treatment in London

Understanding skin infection

The skin is the body’s largest organ and an important barrier against harmful microbes. When this defence is compromised—through cuts, eczema, insect bites, or a weakened immune system—organisms can invade and cause infection. Some infections are superficial and localised, while others can spread into deeper tissues or the bloodstream, leading to potentially serious complications.

Types of skin infection

Bacterial infections

Common bacterial infections include impetigo (crusted sores, often in children), cellulitis (red, painful swelling spreading in the skin), erysipelas, folliculitis, and boils/abscesses. They are most often caused by Staphylococcus aureus or Streptococcus pyogenes.

Viral infections

These include herpes simplex (cold sores, genital herpes), varicella-zoster virus (chickenpox and shingles), molluscum contagiosum, and viral warts caused by human papillomavirus (HPV).

Fungal infections

Also called “dermatophytoses” or “tinea” (ringworm), these infections include athlete’s foot, fungal nail infection, and ringworm on the body or scalp. Candida infections cause thrush and intertrigo (sore rashes in skin folds).

Parasitic infections

Examples include scabies (caused by the mite Sarcoptes scabiei) and lice infestations. These cause intense itching and can spread easily in close contact settings.

Symptoms and warning signs of Skin Infection

• Redness, swelling, heat, or tenderness of the skin.
• Pus, yellow crusting, or discharge from sores.
• Blisters or vesicles (common in viral infections).
• Scaling, cracking, and itching (often in fungal infections).
• Fever, chills, or lymph node swelling in more severe infections.
• Rapidly spreading redness, severe pain, or systemic unwellness—signs of urgent infection needing immediate care.

Skin Infection Diagnosis

A dermatologist usually makes the diagnosis based on clinical appearance. Additional investigations may include:

• Swabs for bacterial culture and sensitivity testing.
• Skin scrapings for fungal microscopy and culture.
• Viral PCR testing for herpes or varicella-zoster.
• Blood tests in severe or recurrent cases.

Skin Infection Treatment options

Bacterial infections

Treated with topical or oral antibiotics depending on severity. Abscesses may require drainage. Prompt treatment helps prevent complications such as cellulitis spreading into the bloodstream.

Viral infections

Cold sores and shingles may be managed with antiviral tablets or creams (acyclovir, valaciclovir). Warts and molluscum may need freezing (cryotherapy), topical agents, or occasionally curettage.

Fungal infections

Usually treated with topical antifungals (clotrimazole, terbinafine). Severe or nail/scalp infections often require oral antifungal tablets.

Parasitic infections

Scabies is treated with permethrin or ivermectin. Lice require topical insecticides or mechanical removal with fine combs.

Complications

Untreated or severe infections can cause abscesses, cellulitis, septicaemia, or post-infective scarring. Recurrent infections may be a sign of underlying conditions such as diabetes or immune deficiency.

Prevention and self-care

• Maintain good personal hygiene and wash hands regularly.
• Avoid sharing towels, razors, or clothing.
• Treat underlying skin conditions promptly (eczema, athlete’s foot).
• Keep wounds clean, covered, and protected.
• Strengthen immunity with a healthy diet, sleep, and exercise.
• Seek medical advice early if an infection does not improve.

Your first visit — what to expect

1. History: Review of symptoms, duration, previous treatments, medical history, and risk factors.
2. Examination: Inspection of the affected skin, with dermoscopy where relevant.
3. Tests: Swabs, scrapings, or cultures where diagnosis is unclear.
4. Management plan: Clear explanation of diagnosis and tailored treatment plan.
5. Follow-up: Advice on prevention, monitoring, and when to return if symptoms recur.

Reviewed by: Dr Mohammad Ghazavi, Consultant Dermatologist
Skinhorizon Clinic, 4 Clarendon Terrace, Maida Vale, London W9 1BZ
Last reviewed: 22 August 2025