General management

The management of an abscess is largely dependent on its site, extension and underlying disease. Treatment of any underlying disease is paramount e.g. diverticular disease, lung carcinoma.

Early and appropriate antibiotics may obviate the need for surgical intervention. A toxic picture indicates the need for blood cultures to optimize antibiotics and further investigation with regard to surgery.

History and clinical findings usually indicate the abscess site. Other techniques include:

• abdominal radiography: may show ileus, soft-tissue mass or chest effusion secondary to subphrenic abscess
• gastrointestinal contrast study may show leak at site of perforation
• ultrasound, very versatile for all soft tissue abscesses
• CT scan, the investigation of choice for cranium, chest or pelvis
• radionuclide scintigram with indium-labelled leukocytes; however, does not differentiate between infection and general inflammation

Surgical treatment depends on site:

• skin lesions may require simple incision and drainage with or without packing of the cavity
• abdominal lesion may be approached with:
  • ultrasound or CT guided percutaneous drainage with catheters left in situ for a prolonged period
  • laparotomy and definitive drainage with closed drainage post-operatively
• pancreatic abscess requires the entire wound to be left open and repeatedly repacked

Collapse of the cavity post-operatively can be checked by injecting contrast medium down the drain. All pus should be sent for culture and the pyogenic membrane should be sent for histology to rule out malignant transformation.