Appendicitis Flashcards
Definition
Acute inflammation of the appendix - complicated (perforated) or uncomplicated
How common?
Most common cause of acute abdomen
Most common abdo surgical emergency (50,000 acute appendicectomies/yr)
Lifetime risk 7-8% (8.6%M, 6.7%F)
Who’s affected?
Any age (10-20yr most common)
Rare before age 2 (appendix larger)
Frequent Abx users
Pathophysiology
Luminal obstruction of appendix - most commonly due to faecolith
Other causes of obstruction: lymphoid hyperplasia (during infection), impacted stool, foreign body, appendicael/caecal tumour
Obstruction –> appendix distention –> bacterial overgrowth –> suppurative inflammation, fills with mucus and swells –> pressure increases in appendix occluding small vessels –> ischameia –> necrosis –> appendiceal rupture –> peritonitis –> sepsis –> death
Risk factors
FHx (3 fold increase) Summer Caucasian Bacterial infection Malignancy of appendix (rare)
Symptoms
Abdominal pain Nausea Vomitiing Anorexia constipation (sometimes diarrhoea) Fever (low grade) general malaise
Abdominal pain in appendicitis
Initially: dull poorly localised periumbilical pain
Worsens and localises over 24-48hrs to: RIF - sharp, well localised pain
Worsened by movement e.g. coughing, driving on uneven roads, hopping
Signs
IN RIF:
- Tenderness
- Rebound tenderness
- Percussion pain
- Guarding
Signs:
- McBurney’s sign
- Rosving’s sign
- Psoas sign
- Obturator sign
If severe –> sepsis (hypotension, tachycardia)
McBurney’s point
2/3rd way from umbilicus to right ASIS
Maximal point of tenderness, rebound tenderness, percussion pain and guarding in appendicitis
Rosving’s sign
RIF pain on LIF palpation
Psoas sign
passive extension of right thigh with patient in left lateral position –> pain in RIF
Psoas sign
passive extension of right thigh with patient in left lateral position –> pain in RIF
Obturator sign
passive internal rotation of flexed right thigh –> pain in RIF
Differentials
GI: IBD, Meckel’s diverticulum, diverticular disease, gastroenteritis, constipation, intussusception, intestinal obstruction, gastroenteritis, biliary colic, cholecystitis, pancreatitis
Renal: ureteric stones, UTI, pyelonephritis
Gynaecological: ruptured ovarian cyst, ectopic pregnancy, pelvic inflammatory disease
Urological: testicular torsion, epididymo-orchitis
Investigations
Bloods: FBC (neutrophil predominant leucocytosis in 80-90%), CRP may be raised
Urine dipstick: exclude UTI
Pregnancy test: exclude ectopic
Imaging: USS, CT (highly sensitive and specific)
