Appendicitis in adults - Guideline for the Investigation and Management of

Publication: 01/01/2009  --
Last review: 25/10/2019  
Next review: 25/10/2022  
Clinical Guideline
CURRENT 
ID: 1415 
Approved By: Improving Antimicrobial Prescribing Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2019  

 

This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.

Guideline for the Investigation and Management of appendicitis in adults

  • Treatment Algorithm
  • Summary
    Appendicitis in adults

    Diagnostic criteria

    • Appendicitis typically presents with colicky periumbilical pain lasting 4-6 hours, which then moves to the right iliac fossa and becomes sharp.
    • Tenderness in the right iliac fossa with such a history is highly suggestive of acute appendicitis.

    Investigations

    • FBC
    • CRP
    • blood cultures x2 (if systemic signs/symptoms of infection)
    • Urinalysis
    • Pregnancy test (to exclude pregnancy)
    • USS abdomen/CT as clinically indicated
    • Operative pus sample (ideally not a swab) if appropriate.

    Non-antimicrobial/Surgical treatment

    • Screen for severe sepsis and manage according to LTHT guideline if present (detail.aspx?id=886)
    • If appendicitis strongly suspected, appendicectomy should be performed without delay. Choice of procedure will be made on a case by case basis by the surgeon.

    Empirical antimicrobial treatment
    In Adults <65yrs: IV Cefuroxime Description: Description: electronic Medicines Compendium information on Cefuroxime 1.5g 8-hourly plus IV Metronidazole Description: Description: electronic Medicines Compendium information on Metronidazole 500mg 8-hourly
    In Adults ≥65 yrs: IV Piperacillin/tazobactam Description: Description: electronic Medicines Compendium information on Piperacillin/tazobactam 4.5g 8-hourly.

    Allergy to penicillins and/or cephalosporins (if not previously tolerated cephalosporins):
    IVCiprofloxacin 400mg 12-hourly   plus IV Metronidazole Description: Description: electronic Medicines Compendium information on Metronidazole 500mg 8-hourly.

    Duration is determined by operative findings

    Normal appendix: Macroscopically normal appendix and no other evidence of infection. No post-operative antibiotics.

    Localised/Simple disease: 2 further post operative doses

    Generalised/Complicated disease: 4 days therapy (review route 48h)

    Oral switch See also LTHT oral switch guidance document

    Oral regimens: PO Co-Amoxiclav Description: Description: electronic Medicines Compendium information on Co-Amoxiclav (Amoxicillin-Clavulanate) (Amoxicillin-Clavulanate) 625mg 8-hourly
    Allergy to penicillins (and previously tolerated cephalosporins): PO Cefalexin Description: Description: electronic Medicines Compendium information on Cefalexin 500mg 8-hourly plus PO Metronidazole Description: Description: electronic Medicines Compendium information on Metronidazole 400mg 8-hourly.
    Allergy to penicillins (and NOT previously tolerated cephalosporins): PO Ciprofloxacin Description: Description: electronic Medicines Compendium information on Ciprofloxacin 500mg 12-hourly plus PO Metronidazole Description: Description: electronic Medicines Compendium information on Metronidazole 400mg 8-hourly.

    Back to top

    Background

    Appendicitis is the most common cause of acute abdominal pain requiring surgical intervention. Approximately 10% of the UK population will develop this disease at some time. In England, approximately 50,000 operations for appendicitis take place annually in the UK. Appendiceal inflammation is thought to occur when the lumen of the appendix is obstructed for example by faecoliths or lymphoid hyperplasia. Bacterial invasion and infection of the obstructed appendix result in an inflammatory process. Bacteriologic studies in appendicitis usually show mixed intestinal flora. Enteric bacteria e.g. Escherichia coli, Enterococcus sp., Bacteroides sp. and Pseudomonas sp. are the most common organisms associated with appendicitis.

    Acute appendicitis can be complicated by perforation with generalized peritonitis or abscess formation which requires a different approach to localized appendiceal infection. Despite advances in imaging and laboratory studies in recent years, patient history and physical examination remain the cornerstone of diagnosis.

    Back to top

    Clinical Diagnosis

    Diagnosis

    History and examination.

    • Appendicitis typically presents with colicky periumbilical pain lasting 4-6 hours, which then moves to the right iliac fossa and becomes sharp [Evidence level A].
    • Tenderness in the right iliac fossa with such a history is highly suggestive of acute appendicitis [Evidence level A].
    • Descriptors of peritoneal irritation (rebound and percussion tenderness, guarding and rigidity) and migration of pain are the strongest discriminators [Evidence level B]
    • Appendicitis can present in many other ways and can be difficult to diagnose, particularly in women [Evidence level B].
    • Appendicitis may be found to be the cause of acute peritonitis at the time of laparotomy [Evidence level B].

    Back to top

    Treatment
    Non-Antimicrobial Treatment
    • Screen for severe sepsis and manage according to LTHT guideline
    • If appendicitis strongly suspected, appendicectomy should be performed without delay [Evidence level A]
    • Laparoscopic appendicectomy has some advantages to open appendicectomy – the choice of procedure will be made on a case by case basis by the surgeon.

    Back to top

    Empirical Antimicrobial Treatment

    Antimicrobial therapy for appendicitis is usually empirical because routine microbiological sampling is not recommended. Empirical regimens should have activity against the organisms that commonly complicate appendicitis i.e. faecal flora. Occasionally complicated cases require reoperation and microbiological sampling is undertaken, empirical therapy may need adjusting to cover the causative organisms in this situation.

    Empirical therapy:

    In Adults <65yrs: IV Cefuroxime Description: Description: electronic Medicines Compendium information on Cefuroxime 1.5g 8-hourly plus Metronidazole Description: Description: electronic Medicines Compendium information on Metronidazole 500mg 8-hourly [Evidence level B]

    In Adults ≥65 yrs: IV Piperacillin/tazobactam Description: Description: electronic Medicines Compendium information on Piperacillin/tazobactam 4.5g 8-hourly [Evidence level C].

    Allergy to penicllins and/or cephalosporins: IV Ciprofloxacin 400mg 12-hourly plus IV Metronidazole Description: Description: electronic Medicines Compendium information on Metronidazole 500mg 8-hourly [Evidence level D]

    Duration of antimicrobial therapy is determined by operative findings as documented in the operation note.

    Normal appendix: Macroscopically normal appendix and no other evidence of infection: No post-operative antibiotics.

    Localised/Simple disease: 2 further post-operative doses [Evidence level D]

    Generalised/Complicated disease: 4 days therapy (review route 48h) [Evidence level D]

    If the patient has known multi-resistant gram negative bacteria, the empiric treatment should be discussed with Microbiology to take these into account.

    Back to top

    Duration of Treatment

    Normal appendix: Macroscopically normal appendix and no other evidence of infection: No post-operative antibiotics.
    Localised/Simple disease: 2 further post-operative doses [Evidence level D]
    Generalised/Complicated disease: 5 days therapy (review route 48h) [Evidence level D]

    Back to top

    Switch to oral agent(s)

    See LTHT oral switch guidance document
    Oral regimens: PO Co-Amoxiclav Description: Description: electronic Medicines Compendium information on Co-Amoxiclav (Amoxicillin-Clavulanate) (Amoxicillin-Clavulanate) 625mg 8-hourly [Evidence level D]

    Allergy to penicillins (and previously tolerated cephalosporins): PO Cefalexin Description: Description: electronic Medicines Compendium information on Cefalexin 500mg 8-hourly plus PO Metronidazole Description: Description: electronic Medicines Compendium information on Metronidazole 400mg 8-hourly. [Evidence level D]

    Allergy to penicillins (and NOT previously tolerated cephalosporins): PO Ciprofloxacin Description: Description: electronic Medicines Compendium information on Ciprofloxacin 500mg 12-hourly plus PO Metronidazole Description: Description: electronic Medicines Compendium information on Metronidazole 400mg 8-hourly. [Evidence level D]

    Back to top

    Treatment Algorithm

    Back to top

    Treatment Failure
    Please contact Microbiology if the patient is not responding to the recommended antimicrobial regimens.

    Back to top

    Provenance

    Record: 1415
    Objective:
    • To provide evidence-based recommendations for appropriate investigation of appendicitis.
    • To provide evidence-based recommendations for appropriate antimicrobial therapy of appendicitis.
    • To recommend appropriate dose, route of administration and duration of antimicrobial agents.
    • To advise in the event of antimicrobial allergy.
    • To set out criteria for referral for surgery or specialist input.
    Clinical condition: Appendicitis
    Target patient group: Adults
    Target professional group(s): Pharmacists
    Secondary Care Doctors
    Secondary Care Nurses
    Adapted from:

    Evidence base

    References

    1. Baird D, Kontovounisios C, Rashid S, Tekkis P. Acute appendicitis BMJ 2017;357:j1703 doi: https://doi.org/10.1136/bmj.j1703
    2. Mui, L. M., C. S. Ng, et al. (2005). "Optimum duration of prophylactic antibiotics in acute non-perforated appendicitis." ANZ J Surg 75(6): 425-8.
    3. Cohn, S. M., P. A. Lipsett, et al. (2000). "Comparison of intravenous/oral ciprofloxacin plus metronidazole versus piperacillin/tazobactam in the treatment of complicated intraabdominal infections." Ann Surg 232(2): 254-62.
    4. Andersen, B.R., Kallehave, F.L., Andersen, H.K. (2005). Antibiotics versus placebo for prevention of postoperative infection after appendicectomy. The Cochrane Database of Systematic Reviews, Issue 3.
    5. Gladman, M. A., Knowles, C. H., Gladman, L. J., Payne, J. G. (2004) Intra-operative culture in appendicitis: traditional practice challenged. Ann R Coll Surg Engl. 86(3): 196–201

    Approved By

    Improving Antimicrobial Prescribing Group

    Document history

    LHP version 2.0

    Related information

    Not supplied

    Equity and Diversity

    The Leeds Teaching Hospitals NHS Trust is committed to ensuring that the way that we provide services and the way we recruit and treat staff reflects individual needs, promotes equality and does not discriminate unfairly against any particular individual or group.