Diverticular Disease


Definition. A weakness in the bowel wall allowing a herniation of the mucosa and submucosa usually at the site where a nutrient vessel penetrates thorough the muscularis. The cause is unknown.

Classical Triad of

  • Fever
  • Leukocytosis
  • Left lower quadrant pain

Risk factors:

  • Age
  • Abnormal Gut Motility (including constipation)
  • Family History
  • Role of NSAIDs is questionable

Incidence ↑

  • ↑incidence with age
  • Inflammatory episode (diverticulitis) < 5% before 40 yo, 60% by 85yrs
  • Present in 1/3 of those at age 45 and 2/3 by age 85

Westernised Societies.

M=F. But males are more likely to suffer diverticulitis.

Sigmoid colon most commonly affected although any part of the gut can be involved.

Common Clinical Entities:


  • Pyrexia
  • Abdominal Tenderness
  • Leukocytosis

Diverticular haemorrhage

  • Classically painless (bright red/wine coloured stool)
  • May be life threatening esp. in elderly

Diverticular Perforation

  • Hippocratic facies
  • Rigid abdomen
  • Very unwell



  • Pyrexia
  • Abdominal Pain:
    • Mild (localized) - Diverticulitis
    • Severe (generalized) - Perforation ± feculent peritonitis
  • Back Pain:
    • Beware perforation
  • Altered bowel habit
  • Nausea/Vomiting
  • Dysuria/Frequency
  • Ask about NSAIDS / Steroids



  • Pyrexia
  • Loss of abdominal movement on respiration
  • Abdominal Tenderness
    • Generalised Tenderness
    • Localised Tenderness
    • Localised Guarding
    • Generalised Guarding
    • Abdominal distension
    • Renal angle tenderness
    • Percussion/Rebound tenderness
    • ↓/Absent bowel sounds
    • PR exam (± pelvic exam)


  • FBC - ↑ WCC?
  • U&E - electrolyte abnormalities/co-existing renal disease
  • Coag (APTT/PTT) - bleeding diathesis, anti-coagulant therapy
  • Erect CXR - Free air present in 70% of perforations
  • PFA - Dilated loops of bowel (obstruction). Check - air in Rectum?
  • MSU - Pyuria - UTI/Haematuria - renal colic
  • PR - Frank blood?

Differential diagnoses

  • Inflammatory Bowel Disease
  • Crohn's Disease
  • Ulcerative Colitis
  • Non-specific colitis
  • Ischaemic Colitis
  • Neoplasia (conditions may co-exist in up to 12%)
  • Adenocarcinoma
  • Leiomyosarcoma
  • Infective Colitis C. Diff C. Diff 027
  • Appendicitis
  • Renal Disease
  • UTI
  • Irritable bowel syndrome


  • Diverticular abscess
    • Systemically unwell, swinging pyrexia, palpable mass
  • Perforation
    • Generalised peritonitis
    • Feculent peritonitis
  • Fistula formation
    • Colovesical = PUO, UTI in Male, Recurrent UTI in female, Pneumaturia
    • Colovaginal (particularly common post hysterectomy) = Faeces PV
    • Colocutaneous
    • Fistula may be neoplastic in the context of diverticular disease
  • Obstruction
    • Secondary to : stricture formation, adhesion formation (prior surgery), occult neoplasm
  • Haemorrhage
    • May be occult
    • entire colon may be full of blood
    • the rectum alone may hold as much as 400mls of blood and clot before the urge to defecate is felt
    • is an arterial bleed from damage to the nutrient vessels within the diverticulae
    • may be very brisk (life threatening)
    • ultimately 80% self-limiting


Acute (severe) presentation

  • Follow ATLS guidelines
  • ABCs
  • Supplemental Oxygen
  • IV access
  • FBC/U&E/Coag
  • Group and Cross Match 2 Units if actively bleeding
  • IVF resuscitation
  • IV Antibiotics (no evidence for in mild cases):
    • Co-amoxiclav 1.2g IV
    • Metronidazole 500mg IV
  • ± Urinary Catheter (urine output)
  • ± NG tube to exclude upper GI cause for bleeding
  • Keep patient fasting ± theatre
  • Bowel rest & antibiotics if admission varranted

Mild disease:

  • Treat as an out patient
  • Liquid diet for 7 to 10 days
  • Analgesia, broad spectrum antibiotics (metronidazole+Ciprofloxacin) are unproven and probably not indicated but our surgical colleagues insist
  • Mandatory surgical OPD follow up
    • Will need colonoscopy after few weeks


Wide degree of severity of presentations overall a diagnosis of exclusion

  • Hinchey grade II or above
  • Systemically unwell or measurable metabolic upset
  • Alteration in more than one vital sign
  • Clinical evidence of any complications of diverticulitis
    • Intra abdominal Abscess, Perforation, Fistula
    • Obstruction, Haemorrhage
  • Unable to confidently exclude serious differentials:
    • Appendicitis, Colitis, Neoplasia
  • Need for IV antibiotics

Hinchey Classification of Clinical Stages of Perforated Diverticular Disease





Pericolic Inflammation Local lower left quadrant tenderness


Pericolic Intra abdominal retroperitoneal abscess Local lower left quadrant tenderness


Generalised Purluent Peritonitis Diffuse abdominal tenderness, rebound


Generalised Feculent Peritonitis Diffuse abdominal tenderness, rebound

Pitfalls :

  • A disease of the elderly who already have reduced physiological reserve
  • Failure to recognize the significance of the possible blood loss or potential for blood loss
  • ß blockade
  • Regular Paracetamol masking pyrexia
  • Right lower quadrant pain may be a redundant diverticular sigmoid colon


  • Overall Mortality 1-5%
  • Of complicated diverticulitis 15% percent require surgery
  • 1/3 get better and become asymptomatic
  • 1/3 get better but have non-specific symptoms
  • 1/3 will have second episode
  • Of those with a second episode up to 60% will experience complications
  • Only 10% are asymptomatic following second attack

Hospitalisation also warranted:

  • Unable to tolerate oral hydration
  • Systemic signs such as fever,tachycardia etc. develop
  • Immunocompromised patients
  • Severe pain requiring IV analgesia

Discharge advice

  • Complete course of antibiotics
  • High Fibre Diet
  • Long term Weight reduction, Exercise
  • Return if symptoms do not settle


  • Usually do not perform endoscopy until 6 weeks post discharge
  • Usually will not make the diagnosis in the acute setting with a Ba Enema (risk of perforation and barium peritonitis)

Surgical options

  • Order a CT !
  • Percutaneous drainage of abscesses
  • Surgical drainage of abscess
  • Colonic resection
  • Laparoscopic washout

Content by Dr Trajan Cuellar and Dr Syed Aliu Naqi. Last review Dr ÍOS 20-Aug-2023.