Diverticulosis thought to be due to increased intraluminal pressure due to American diet (low fiber, high fat, high carbs). Obesity and sedentary lifestyle are RF.
Diverticulitis due to erosion thru wall from thickened poop. Anaerobic bacteria: Bacteroides, Peptostreptococcus, Clostridium, Fusobacterium. GN rods such as E.Coli. (this was the reason for triple abx – GP, GN, Anaerobes: Amp/Gent/Flagyl).
Usually in the older population (>50yo), though it is trending in younger population, particularly male and obese. Recurrence rate 20-40%.
LLQ pain, fever, leukocytosis (45% will have normal WBC). 30% have diarrhea, 50% have constipation. N/V (60%), anorexia (40%), urinary symptoms (10% – due to adjacent inflammation). Tenderness only in LLQ + absence of vomiting + CRP > 50mg/L has a LR + 18 (Lameris, 2010).
CT preferred imaging study, though do not necessarily need if patient has prior hx and similar presentation. CT will recurrence if initial therapy does not improve symptoms. CT findings: retroperitoneal fat stranding (most sensitive); does not require contrast (IV or PO) for fat stranding (Tack, 2005), though can miss ischemia or abscess.
Ultrasound: hypoechoic peridiverticular inflammatory reaction ‘Dome sign‘ , mural/peridiverticular abscess formation w/wo gas, bowel wall thickening > 4mm at point of maximal tenderness, presence of diverticula in surrounding segments.
Uncomplicated: inflammation of the diverticula. Complicated (10-20%): inflammation with: abscess, stricture, obstruction, fistula, or perforation. Hinchey stages: Stage I: small, confined pericolic/mesenteric abscess, Stage II: larger abscesses, often confined to pelvis; Stage III: perforated diverticulitis with large abscess; Stage IV: free perforation with fecal contamination of peritoneal cavity, generalized peritonitis.
Uncomplicated: Clear liquid diet (2-3d) + oral antibiotics. 70-100% success rate, specifically if uncomplicated confirmed with CT. Complicated: Admission, bowel rest, IV antibiotics.
Antibiotics: Outpatient (7-14d): Metronidazole 500mg q8h + Cipro 500mg q12h, or Levofloxacin 500mg qd or Clindamycin 300mg q6h or Bactrim DS q12 or Augmentin 875mg q12 or Moxifloxacin 400mg qd. Also Cefoxitin or Cefazolin + Metro. Single vs double agent regiments?: same efficacy (Kellum, 1992). Inpatient: Unasyn 3g q6h or Zosyn 3.35g q6h/4.5g q8 or Ertapenem 1g qd or Timentin 3.1g q6h or Moxifloxacin 400mg qd or Metronidazole 500mg q6h + Levofloxacin 750mg qd or Cipro 400mg q12h. Also Cefepime +Metro.
Most abscess Stage II or > 4cm require percutaneous drainage. Perforation has high mortality rate, consider emergent exploratory surgery. Stage III mortality rate 13%, Stage IV 43%.
No abx at all?: Chabok, 2012: CT-confirmed uncomplicated diverticulitis. Randomized into admission with IV fluids alone vs IV fluids + abx. 623 pts. No difference in hospital LOS (3d median), no statistical difference in complications (1.9% vs 1.0%, p=0.302), recurrent diverticulitis at 1y (16%). Though 10 from no-abx group crossed over into abx group due to increased pain.
Regardless, needs colonoscopy in 6 weeks after resolution due to CT scan unable to differentiate carcinoma.
No evidence backing cessation of seeds/nuts for prevention (Strate, 2008). Recommended high fiber diet for possible prevention.
Small fat-filled sacs near lining of colon. Can become inflamed due to torsion or venous thrombosis. Generally younger population (average 35yo). Presents with sharp pain with n/v, appears similar to appendicitis, normal labs. Usually benign, self-limiting course. Tx: pain management and f/u in 1 week.