appendix mass

Last reviewed 01/2018

An appendix mass is an inflamed appendix with an adherent covering of omentum and small bowel. The history is similar to that of appendicitis with a longer duration since onset. Examination reveals a mass in the right iliac fossa.

There is debate whether an appendix mass should require early surgery, or, whether conservative treatment is most appropriate. An alternative in those with a well-defined abscess at presentation is CT-guided drainage. CT drainage has become a successful way of deferring operation in those who are not otherwise fit for surgery.

Conservative management includes:

  • nil by mouth
  • antibiotics, e.g. metronidazole 500mg/8h i.v. and cefuroxime 750mg/8h i.v.
  • the size of the mass should be marked out and surgery is indicated if either:
    • the mass enlarges or
    • small bowel obstruction supervenes due to adhesions or
    • the patient becomes more toxic, e.g. increased pulse, increased WCC, increased pain, increased temperature

It is usual to do a delayed appendicectomy 6-8 weeks later, even if the mass resolves on conservative treatment. However, about 15-20% of patients will be readmitted with similar symptoms before the 'interval appendicectomy'.

Note that it is important to exclude a colonic carcinoma in those beyond middle age when symptoms settle. Barium enema or colonoscopy are first-line investigations.