Makindo Medical Notes

Pruritus Ani

Pruritus ani refers to itching in the perianal area and is a symptom of various underlying conditions.

Local Causes

• Poor hygiene
• Excessive sweating
• Anal fistula
• Haemorrhoids
• Neoplasia
• Warts
• Fungal infections
• Contact dermatitis (e.g., deodorants)
• Worm infestations
• Antibiotics (due to complications like diarrhoea or fungal infections)

General Causes

• Diabetes mellitus
• Obstructive jaundice
• Hodgkin's disease

Dermatological Causes

• Scabies
• Pediculosis (lice infestation)
• Psoriasis
• Atopic eczema

In many cases, pruritus ani is idiopathic or psychogenic. Often, an 'itch-scratch' cycle is created, where scratching exacerbates the symptoms, even after the initial cause has been resolved.

Symptoms and Signs

• Itching tends to worsen at night, regardless of the cause.
• A history of precipitating factors such as antibiotics, diabetes, or pruritus elsewhere may be present.
• The perianal skin may appear normal or could be inflamed, moist, or macerated.
• Digital rectal examination (PR) and proctoscopy are essential to rule out anal conditions such as fistulas.

Investigations

• Hemoglobin (Hb) levels
• Urine tests
• Blood sugar levels
• Perianal scrapings for fungal microscopy

Treatment

The treatment is specific to the underlying cause. Non-specific management includes:

• Maintaining good hygiene
• Following a suitable diet
• Wearing loose, breathable underclothes
• Gentle cleansing after defecation with simple soap
• Application of glycerine and witch hazel
• Topical hydrocortisone and local anesthetic creams for symptom relief

In some cases, pruritus ani may be challenging to treat and requires persistent management.