Table of Contents
- diverticula are herniations of the mucosa and submucosa or the entire wall thickness through the muscularis and in Western cultures, 95-95% involve the sigmoid colon, while in those living in Africa and Asia, prevalence is only 0.2% of the population and it mainly affects the right side!
- adolescent cases are rare and generally associated with genetic disorders involving connective tissues in particular, such as:
- Ehlers-Danlos syndrome
- Marfan's syndrome
- Meckel's diverticulum is a rare congenital form but can present in adults
- prevalence is increasing in the Western cultures and now are found in over 25% of patients undergoing colonoscopy, with prevalence increasing with age with prevalence being ~5% in those adults under 40 years, ~30% by age 60 years and 65% by age 85 years.
- thought to be caused by low-fiber diet which is the highest risk factor for diverticular disease. The resultant low-bulk stool leads to increased segmentation of the colon during propulsion, causing increased intraluminal pressure and formation of diverticula.
- affluent, mainly indoor societies in which passing flatus is regarded as being anti-social, may be an important contributor due to the gas pressures resulting from flatus retention and colonic contractions - perhaps it is better out than in!
- risk increases with steroids and aging presumably due in part to impaired collagen maintenance.
- complications of diverticular disease include:
- 15% of those with diverticular disease will develop lower GIT bleeding - of these, 1/3rd will develop massive bleeding.
- usually sudden onset of painless, bright red or wine colored stools and is often massive but usually stops spontaneously
- initial presentation may be as perforation and peritonitis
- mortality following free perforation and generalised peritonitis exceeds 20%
- diverticulitis +/- abscess formation +/- perforation +/- fistula formation
- may result in altered bowel habit, lower abdominal pain, tenesmus, flatulence, distension, fevers, ureteric irritation,
initial Mx in ED
- initial assessment as per the patient with acute abdominal pain in the ED
- if rectal bleeding is the main presentation, then Mx as per lower GIT bleeding
- nil orally or minimal ice chips to rest gut
- iv fluids
- bloods for FBE, U&E, consider CRP (and LFT's and lipase if R abdominal pain, consider blood cultures if temp > 38.5degC)
- iv analgesia
- consider anti-emetics if no evidence of bowel obstruction (see large bowel obstruction)
- strict fluid balance chart
- consider NGT if frequent vomiting
- consider IDC if clinical dehydration, or impaired renal function
- ECG if over 50 years age or risk of IHD
- plain AXR is unlikely to be helpful unless one suspects other diagnoses such as bowel obstruction or sigmoid volvulus
- contact surg team to decide on further Mx and possible CT abdomen
- patients with known diverticular disease and mild symptoms may be considered for discharge on broad spectrum antibiotics without imaging
- pelvic USS may be preferred over CT scan for women of child bearing age
- CT abdomen with iv and oral contrast is now the gold standard for non-invasive diagnosis of diverticulitis
- the two most common CT findings in uncomplicated diverticulitis are:
- colonic wall thickening (wall thickness > 3 mm on the short axis of the lumen)
- pericolic fat stranding
- an identifiable inflamed diverticulum may also be visible
- CT may fail to demonstrate early, mild cases of diverticulitis.
- CT findings in complicated diverticulitis may include:
- the presence of an abscess (defined as a fluid-containing mass with or without air and an enhancing wall)
- contained or free extraluminal air bubbles or pockets
- CT with rectal contrast is usually required to visualise fistulae, however, this is rarely performed
antibiotic Mx of diverticulitis
mild diverticulitis suitable for outpatient Mx
- augmentin duo forte i bd for 5-7 days
- if penicillin HS, then cephalexin 500mg qid plus metronidazole 400mg bd for 5-7 days
moderate diverticulitis warranting admission and iv Rx
- iv amoxicillin with clavulonic acid is usual preference if available and covers Enterococcus whereas ceftriaxone doesn't and doesn't have dosing complexities and ototoxicity of gentamicin
- iv ampicillin 1g 6h PLUS iv metronidazole 500mg 12h PLUS iv gentamicin 4-6mg/kg/day adjusted to age, creatinine clearance and gentamicin levels
- iv ceftriaxone + iv metronidazole is an option for those sensitive to penicillins
- if HS or C/I then contact infectious diseases team to decide on alternative Rx
- continue iv for 5-7 days then change to oral regime once clinical condition is improving and tolerating oral fluids for at least 24 hours
- as for moderate but increase iv ampicillin dose to 2g per dose
abscess on CT scan
- surg team to consider interventional radiology to drain it, or resort to bowel resection
diverticulitis.txt · Last modified: 2021/12/15 01:27 by gary1