Pilonidal disease

• Pilonidal disease encompasses the acute presentation of a pilonidal abscess and the chronic condition pilonidal sinus. These are related conditions involving the natal cleft
• A pilonidal abscess is a painful, pus-filled infection that results from hair penetrating the skin. A chronic pilonidal sinus, on the other hand, is a persistent tract under the skin where hair and debris collect, often leading to recurrent infections.
• Causes:

  • Not clear
  • Could be due to occlusion of a hair follicle, damage to a hair follicle (causing hair to poke through surrounding skin), or someone born with a hole within the natal cleft that can trap and collect loose hair
  • Abnormal collection/growth of hair causing inflammation and formation of a pit which subsequently fills with more hair/dead skin/debris
  • Causes further inflammation resulting in a deep cavity in the subcutaneous tissue with a sinus tract that connects the pit to the surface of the skin
• Risk factors:

  • Male sex
  • Age 16-40
  • Coarse dark hair
  • Hirsutism (excessive hair)
  • Obesity
  • Diabetes
  • Caucasian
  • Jobs involving long seated periods e.g. lorry drivers
• Symptoms:

  • Acute abscess - pain, erythema and swelling in the natal cleft. May have systemic symptoms
  • Chronic disease - multiple infective episodes, may have chronic leakage
• Pilonidal disease is diagnosed clinically, and further tests are rarely required. In extensive disease with complex pits and sinuses, an MRI scan can be performed to delineate disease and aid surgical planning.
• In recurrent disease, it is appropriate to test for diabetes.
• Antibiotics can be used to treat small abscesses acutely or for low-grade septic episodes.
• Presentation:

  •Can be asymptomatic (one or more non tender pits in midline of natal cleft)

  •Can be chronically discharging (serous or purulent discharge, irritated skin from discharge)

  •Can present as acute abscess (painful, tender lump in or near natal cleft, fluctuant, purulent discharge, may be associated fever/cellulitis)
• General management for all:

  • Advice on reducing risk of recurrence
  • Hygiene
  • Buttock hair removal
• Management:

  • Asymptomatic disease: watch and wait
  • Chronic discharging disease: refer to surgeons for treatment (e.g. excision and laying open or excision and primary closure of the tract), analgesia
  • Acute pilonidal abscess: admit urgently under surgeons for incision and drainage, analgesia
• Rarely a self limiting disease and surgery is mainstay of treatment