Appendicitis (acute inflammation of the appendix) is thought to be caused by infection secondary to obstruction of the lumen of the appendix.  The main causes of obstruction are faecolith (hard mass of faecal matter), normal stool, and lymphoid hyperplasia (secondary to viral infection).  Other causes include fragments of indigestible food, mucus, parasites, and/or tumours.  Appendicitis is one of the most common causes of an acute abdomen in adults and children in the UK. It accounts for more than 40,000 hospital admissions in England every year. Appendicitis is most common between the ages of 10–20 years but can occur at any age, and is slightly more common in men than women, with a male to female ratio of 1.4 to 1.  Appendicitis may resolve spontaneously, but complications, such as perforation, are more likely if the appendix is not removed


When to suspect appendicitis

  1. Take a history
    1. The classic symptoms of appendicitis are:
      1. Abdominal pain — this is the most common presenting complaint in people with acute appendicitis:
        1. Typically a peri-umbilical or epigastric pain that worsens during the first 24 hours (becoming constant and sharp) and migrates to the right iliac fossa (RIF)
        2. The pain is worsened by movement (such as coughing and driving over speed bumps)
        3. In children, if asked to hop the child will refuse as this causes pain
      2. Anorexia — this is almost always present
      3. Nausea
      4. Constipation
      5. Vomiting — profuse vomiting may indicate development of peritonitis
  2. Perform a physical examination
    1. The classic signs of appendicitis are:
      1. Tenderness on percussion
      2. Guarding (muscular rigidity at the RIF)
      3. Rebound tenderness
      4. Facial flushing
      5. Dry tongue
      6. Halitosis
      7. Low-grade fever (not more than 38°C), and/or
      8. Tachycardia
    2. Less common peritoneal signs include:
      1. Rovsing's sign — palpation of the left lower quadrant increases the pain felt in the right lower quadrant
      2. Psoas sign — extending the right thigh with the person in the left lateral position elicits pain in the right lower quadrant
      3. Obturator sign — internal rotation of the flexed right thigh elicits pain in the right lower quadrant
    3. A rectal examination is not routinely recommended in primary care
  3. Be aware that the classic features of appendicitis may not always be present — see the section on Atypical presentation of appendicitis for more information
  4. Assess the person for signs of complications:
    1. Tachycardia and sudden relief of pain may be signs of a perforated appendix
    2. A palpable abdominal mass and swinging pyrexia may be signs of an appendix abscess
    3. Profuse vomiting, high fever (more than 40°C), severe abdominal tenderness, and absent bowel sounds may be signs of peritonitis
  5. Exclude other possible causes of abdominal pain  e.g. if a gynaecological cause is suspected, consider performing a pelvic examination (if appropriate)


Atypical presentation of appendicitis

Be aware that the classic presentation of appendicitis appears in only about 50% of people and can be influenced by the following:

  1. Older age — even with advanced inflammation, pain may be minimal and fever absent. The person may also present with confusion and shock
  2. Young age — infants and young children may show only vague abdominal pain and anorexia, and may seem withdrawn
  3. Pregnancy  displacement of the appendix by the gravid uterus can result in an atypical presentation:
    1. Right lower quadrant pain and tenderness dominate in the first trimester. In the latter part of pregnancyright upper quadrant or right flank pain may occur
    2. Nausea and vomiting are often present but may be mistaken for pregnancy-related symptoms
  4. The anatomical position of the appendix (which can vary considerably in non-pregnant people):
    1. A retrocaecal/retrocolic appendix may present with right loin pain and tenderness and a positive psoas test.  Muscular rigidity and tenderness to deep palpation are often absent because of protection from the overlying caecum
    2. A pre-ileal and post-ileal appendix may present with vomiting and diarrhoea
    3. A subcaecal and pelvic appendix may present with suprapubic pain and urinary frequency; diarrhoea and tenesmus may be present due to rectal irritation; abdominal tenderness may be lacking, but rectal or vaginal tenderness may be present on the right side; microscopic haematuria and leukocytes may be present on urinalysis
    4. A long appendix with tip inflammation in the left lower quadrant may cause pain in that region



There is no single investigation that can completely rule out appendicitis; however, the following may be useful to support the diagnosis and/or rule out differential diagnoses:

  1. Pregnancy test — to exclude pregnancy, including ectopic pregnancy, in women of childbearing potential
  2. Urine dipstick test — to help exclude a urinary tract infection. Be aware that this may be abnormal in about 50% of people with acute appendicitis because of inflammation adjacent to the right-sided urinary tract and bladder. See UTIs in childrenUTIs in men and UTIs in women for more information
  3. FBC and CRP — to rule out infection:
    1. Full blood count — neutrophil predominant leucocytosis is present in 80–90% of people with appendicitis
    2. CRP — raised levels may be present, but normal levels do not exclude the diagnosis of appendicitis


Management of suspected appendicitis

Arrange immediate hospital admission if appendicitis is suspected

  • Have a very low threshold for admitting:
    • Infants and young children
    • Elderly people
    • Pregnant women
    • People with signs of complications


NOTEAppendicectomy is the treatment of choice in secondary care for people with appendicitis


Abdominal Pain Poster


Blood tests / Phlebotomy

If your practice does not have a practice nurse who is trained to take bloods, you can refer a patient to the Pathology Department at East Kent Hospitals for a blood test (find details here)

Alternatively, Buckland Hospital (Dover) and the Royal Victoria Hospital (Folkestone) both operate a walk-in service where no appointment is necessary, except for if the patient requires a Glucose Tolerance Test (GTT).  In the event that a GTT is required, please call 01304 222552 (for Buckland) and 01303 854484 (for Royal Victoria) to arrange a suitable appointment

Please ensure that the patient remembers to take with them their blood test form to the walk-in centres

Advice and Guidance is being made available for all specialties, and is being provided by consultant specialists at East Kent Hospitals.  To make a request or to check to if a query has been answered, you will need to log in via the electronic Referral System (eRS)

Click here for the "how to access" e-Referral Advice and Guidance Manual for instructions on how to make a request and check responses

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