Pruritus ani is the medical term for itching around the anus. It is a symptom, not a diagnosis, and can be due to a wide variety of causes - local, systemic, dermatological, or idiopathic. The chronic "itch–scratch cycle" often perpetuates symptoms even when the initial trigger has resolved.

📍 Local Causes

🚻 Poor perianal hygiene (or conversely, overzealous cleaning causing irritation).
💦 Excessive sweating and moisture retention (common in warm weather or obesity).
🔧 Anal fistula with persistent discharge.
🔴 Haemorrhoids causing mucous seepage.
🧬 Anal or perianal neoplasia (rare but important to exclude).
🦠 Viral warts (HPV-related).
🍄 Fungal infections such as Candida albicans.
🧴 Contact dermatitis (to soaps, deodorants, wipes).
🪱 Worm infestations (especially Enterobius vermicularis in children).
💊 Antibiotics → diarrhoea or candida overgrowth.

💡 Clinical Pearls: - Always exclude sinister causes (anal carcinoma, HIV-related lesions) in persistent or refractory pruritus ani. - Nocturnal itch in children → think of Enterobius (threadworms). - Many cases remain idiopathic, and managing the itch–scratch cycle with behaviour modification is key. - In resistant cases, dermatology or colorectal referral may be needed.

🌍 General/Systemic Causes

🍬 Diabetes mellitus (secondary infections, candidiasis).
💛 Obstructive jaundice (bile salt deposition in skin).
🧪 Hodgkin’s lymphoma (generalised pruritus).

🩺 Dermatological Causes

🕷️ Scabies.
🪳 Pediculosis (pubic lice).
🧴 Psoriasis (may involve perianal area).
🌿 Atopic eczema or lichen sclerosus.

🔍 Symptoms and Signs

🌙 Nocturnal worsening of itch (classic, esp. in worm infestation).
📝 History of triggers - antibiotics, diabetes, jaundice, skin disease.
👀 Perianal skin: may be normal, erythematous, moist, excoriated, or thickened.
🤲 PR exam and proctoscopy essential to rule out haemorrhoids, fissures, or fistulae.

🧪 Investigations

📊 FBC (Hb) - chronic blood loss/anaemia.
🧪 Urine dip and blood sugar - screen for diabetes.
🔬 Perianal scrapings for fungal microscopy.
🪱 Cellophane tape test in children (for pinworm ova).
📸 Consider biopsy if suspicious lesion.

💊 Treatment

Management is twofold: treat the underlying cause and provide symptomatic relief.

🧼 Maintain meticulous but gentle hygiene - avoid excessive scrubbing.
🥗 High-fibre diet & adequate hydration - prevent constipation and straining.
🩲 Loose, breathable cotton underwear - avoid sweating and chafing.
🚿 Wash with plain water or mild soap after defecation; pat dry (not rub).
🌿 Apply soothing agents (glycerine, witch hazel, zinc oxide barrier cream).
💊 Topical 1% hydrocortisone or mild steroid + local anaesthetic for short-term relief.
🪱 Anthelmintics (e.g., mebendazole) if pinworms suspected.
🍄 Topical antifungal if candida infection confirmed.

The content on this website is provided for educational and informational purposes only to support exam preparation (e.g., MLA, MRCP, USMLE) and learning. This is NOT medical advice, diagnosis, treatment, or professional guidance. It does not replace consultation with a qualified healthcare professional, official guidelines (e.g., NICE, GMC, BNF), or supervised clinical practice. Always verify information with current, authoritative sources. Makindo and its contributors accept no liability for any reliance on this content, including errors, omissions, or any resulting harm, loss, or consequences. By using this site, you agree to these terms.

Pruritis ani