[18] Acute Appendicitis Flashcards
What is appendicitis?
Inflammation of the appendix
What causes appendicitis?
Direct luminal obstruction
What is appendicitis secondary too?
Usually faecolith, but may also be due to lymphoid hyperplasia, impacted stool, or an appendiceal or caecal tumour
Who does acute appendicitis usually affect?
Those in their second or third decade
What is the lifetime risk of acute appendicitis?
7-8%
What are the risk factors for acute appendicitis?
Family history
Ethnicity
Environmental - more common during Summer
What % of risk of appendicitis does genetics account for?
Around 30%
How does ethnicity affect the risk of acute appendicitis?
It is more common in Caucasians, yet ethnic minorities are at greater risk of perforation if they do get it
What are the symptoms of acute appendicitis?
Abdominal pain
Nausea and vomiting
Anorexia
Diarrhoea or constipation
Describe the pain in acute appendicitis
It is initially peri-umbilical, dull, and poorly localised, but later migrates to the right iliac fossa, where it is well-localised and sharp
Describe the timing of the vomiting in appendicitis
It is typically after the pain, not preceding it
What may be found on examination in acute appendicitis?
Patients may be tachycardic, tachypnoeic, and pyrexical
When examining the abdomen, the most specific findings are rebound tenderness and percussion pain at McBurney’s point, as well as potential signs of guarding if perforated
Where is McBurneys point?
2/3 of the way between the umbilicus and the ASIS
How might an appendiceal abscess present on examination?
RIF mass
What ‘textbook signs’ may be found on examination in acute appendicitis?
Rovsing’s sign
Psoas sign
What is Rovsing’s sign?
RIF pain on palpation of the LIF
What is the psoas sign?
RIF pain with extension of the right hip
What does psoas sign suggest?
An inflamed appendix abutting psoas major muscle in a retrocaecal position
How useful in clinical signs of appendicitis in diagnosis?
They have a poor predictive value alone, but are stronger in concert
What is required in females of reproductive age with suspected appendicitis?
Pelvic examination, to assess for any potential gynaecological pathology
What is the most important differential diagnoses to consider in acute appendicitis in the younger female patient?
Gynaecological pathology, especially ectopic pregnancy or ovarian cyst rupture
What are the other gynaecological differential diagnoses of acute appendicitis?
Pelvic inflammatory disease
What are the renal differential diagnoses of acute appendicitis?
Ureteric stones
Urinary tract infection
Pyelonephritis
What are the gastrointestinal differential diagnoses of acute appendicitis?
Diverticulitis
IBD
Mesenteric adenitis
Meckel’s diverticulum
What are the urological differential diagnoses of acute appendicitis?
Testicular torsion
What investigations may be done in suspected acute appendicitis?
Urinalysis
Blood tests
Imaging
Why should urinalysis be done for all patients with suspected appendicitis?
To exclude UTI or any other renal/urological causes
What finding on urine dipstick can be present in appendicitis?
Leucocytes
What urine test is vital for any woman of reproductive age?
Pregnancy test
What blood tests will be done in suspected acute appendicitis?
FBC and CRP
Baseline blood tests required for pre-operative assessment
Serum ß-hCG
Why are FBC and CRP done in suspected acute appendicitis?
To assess for raised inflammatory markers (raised WCC and CRP)
When will a serum ß-hCG be done in suspected acute appendicitis?
If ectopic pregnancy still has not been excluded
Is imaging required to diagnose or treat appendicitis?
No, as most cases should be a clinical diagnosis
When might imaging be used in suspected acute appendicitis?
If the clinical features are inconclusive, and an alternative diagnosis is sought
What imaging can be used in acute appendicitis?
Trans-abdominal ultrasound
CT scan
Why is a CT scan useful in elderly patients with suspected appendicitis?
Due to the potential of malignancy causing appendicitis, as treatment would be different
What is the advantage of trans-abdominal ultrasound in acute appendicitis?
Good sensitivity and specificity
Who is trans-abdominal USS most useful in with acute appendicitis?
Children
Why is trans-abdominal ultrasound most useful in children with acute appendicitis?
Less abdominal fat
Will be exposed to lower levels of radiation
What is the purpose of risk stratification scores in appendicitis?
They attempt to assist in the diagnosis of appendicitis
Give two examples of risk stratification scores in appendicitis?
Alvarado score
Appendicitis Inflammatory Response Score
What is it important to consider when using risk stratification scores for appendicitis?
The score should only be used to assist the surgeon in their decision making, and should not replace their clinical judgement
What does the Appendicitis Inflammatory Response Score aim to triage patients into?
Low risk
Intermediate risk
High risk
What are the parameters in the Appendicitis Inflammatory Response Score?
Vomiting - 1 point
RIF pain - 1 point
Pyrexical (>38.5) - 1 point
WBC - 10-14.9 = 1 point, >15 = 2 points
Polymorphonuclear leukocytes - 70-84% = 1 point, >85% = 2 points
CRP - 10-49 = 1 point, >50g = 2 points
Rebound tenderness or guarding - light = 1 point, medium = 2 points, strong = 3 points
How many points is considered to be low risk in the AIR score?
0-4
What management is required for low risk appendicitis according to the AIR score?
No intervention required
How many points is considered to be medium risk in the AIR score?
5-8
What management is required for medium risk appendicitis according to the AIR score?
Inpatient observation or further imaging
How many points is considered to be high risk in the AIR score?
9-12
What management is required for high risk appendicitis according to the AIR score?
Surgical exploration recommended
What is the current definitive treatment for acute appendicitis?
Laparoscopic appendicetomy
Should conservative antibiotic therapy be used in uncomplicated appendicitis?
There is some debate about this - a Cochrange analysis found that whilst appendectomy should remain the standard treatment, further research is still warranted. Primary antibiotic treatment for simple inflamed appendix can be successful, but has a failure rate of 25-30% in one year
Why is appendicitis sometimes treatable with antibiotics, and sometimes not?
The current theory suggests that appendicitis appears in two seperate forms - one type is a simple reversible inflammation, whilst a second type will rapidly progress to gangrene and perforation. The former can be treated successfully with antibiotics, the latter requires surgical intervention
What findings appear to predict antibiotic success?
CRP <60
WBC <12 x 10^9
Age <60
Why is laparoscopic appendectomy the gold standard for treating appendicitis?
Due to a very low morbidity from the procedure, and the risk of possible readmission if treated with antibiotic therapy alone
What is the additional advantage of a laparoscopic appendectomy in females?
It allows for better visualisation of the uterus and ovaries
What should be done when any removed appendix following appendicitis?
It should be sent to histopathology to look for malignancy
What malignancies typically arise in the appendix?
Carcinoid
Adenocarcinoma
Mucinous cystadenoma
What should be done during a laparoscopic appendectomy, as per any laparoscopic procedure?
The entirety of the abdomen should be inspected for any other evident pathology, including checking for any Meckel’s diverticulum present
What approach to appendectomy may be used in pregnancy?
An open approach
What is the advantage of a laparoscopic appendectomy over an open approach?
A laparoscopic approach has been shown to reduce hospital stay and has an earlier return to baseline activity
What is the mortality associated with appendicitis in developed health systems?
Low - 0.09 - 0.24%
What are the complications of acute appendicitis?
Perforation
Wound infection
Appendix mass
Pelvic abscess
What causes an appendix mass after appendicitis?
The omentum and small bowel adhere to the appendix
What is involved in the traditional management of an appendix mass after appendicitis?
Conservative approach with antibiotics
What % of cases of appendicitis are complicated by a pelvic abscess?
9.4%
Where are pelvic abscesses following appendicitis more common?
In perforation
How does a pelvic abscess present?
Fever with palpable RIF mass
What does a pelvic abscess typically require for confirmation?
US scan or CT scan
How are pelvic abscesses managed?
Usually with antibiotics and percutaneous drainage of abscess
What is immediate surgery for pelvic abscesses associated with?
Increased morbidity and ileo-caecal resection
What follow up is recommended after conservative treatment for pelvic abscesses?
Follow-up with CT scan for patients over >40years
Why is follow up with CT scan recommended for patients >40 years with pelvic abscesses?
Due to around 2% prevalence of concurrent malignancy
