Peritonitis

Question 1

Define peritonitis

Answer 1

Inflammation of the peritoneum

Question 2

Aetiology of peritonitis

Answer 2

Infectious:
GI perforation:
External:
- Abdominal trauma
- Ingestion of sharp foreign body
- Endoscopy
- Surgery
Spontaneous bacterial peritonitis
- E. Coli
- Klebsiella
- Streptococcus

Leakage of sterile body fluid into peritoneum (which may become subsequently infected)
- Blood: endometriosis, abdominal trauma
- Gastric juice: peptic ulcer, gastric carcinoma
Bile: liver biopsy
- Urine: pelvic trauma
- Menstruum: salpingitis
- Pancreatic juice: pancreatitis
Sterile abdominal surgery

Question 3

What may cause perforation that can lead to peritonitis

Answer 3

Boerhaaves perforation
Peptic ulcer rupture
Gastric carcinoma rupture
Appendicitis
Diverticulitis
Meckel diverticulum
IBD
Intestinal infarction
Intestinal strangulation
Colorectal carcinoma
Meconium peritonitis
Cholecystitis

Question 4

Symptoms of Peritonitis

Answer 4

Abdominal pain (generalised → localised due to involvement of somatically innervated parietal peritoneal layer, | exacerbated by movement)
Bloating
Nausea and vomiting
Fever

Question 5

Signs of Peritonitis on examination

Answer 5

Diffuse abdominal tenderness
Patient lying still
Guarding / rigid abdomen
Rebound tenderness
Sinus tachycardia

Rovsing’s sign (palpation of the LIF causes pain in the RIF)
Psoas sign (extending the right thigh to the left lateral position elicits RLQ pain)
Obturator sign (internal rotation of the flexed right thigh elicits pain in the RLQ)

Question 6

Investigations for Peritonitis

Answer 6

FBC, CRP, Blood cultures, U&Es, LFTs

US: ?ascites
Ascitic tap: >250 polymorphonucleate cells per uL
Erect CXR: pneumoperitoneum
AXR: dilated oedematous intestines

Question 7

Management for peritonitis

Answer 7

Treat the cause of peritonitis

Supportive:
- IV fluids
- Correct electrolytes
- Abx: piptazobactam (tazocin)or cefotaxime

Surgery (exploratory laparotomy + lavage of peritoneum)

Question 8

Prophylaxis for peritonitis

Answer 8

Prophylaxis: ciprofloxacin + propranolol (beta blocker)

If you have an ascites and a protein (not SAAG) of ≤15g/L, then START prophylaxis

Question 9

Complications of peritonitis

Answer 9

Sequestration of fluid and electrolytes → electrolyte disturbance, hypovolaemia
Hypovolaemia → shock, acute renal failure
Peritoneal abscess
Sepsis