P1: RLJ/OZN P2: KUF
0521779407-D-01 CUNY1086/Karliner 0 521 77940 7 June 13, 2007 7:41
Diverticulitis 495➣diverticula (plural)
➣diverticulosis (presence of diverticula)
➣diverticulitis (inflammation caused by micro perforation of a
diverticulum)
■Diverticula develop in the bowel at sites of potential weakness where
other structures penetrate circular smooth muscle
■Most diverticula occur in colon related to low residue diets,
decreased stool volume, increased intraluminal pressure, increased
colonic wall tension
■Colonic diverticula are mostly acquired starting at age 30–40 years
■Colonic diverticula always form on mesenteric side of antimesen-
teric teniae (bands of longitudinal smooth muscle) at sites of passage
of neurovascular bundle to submucosa
■Other diverticula – descending duodenum at site of penetration of
wall by bile and pancreatic ducts at papilla of Vater
■Some diverticula are congenital – most importantly, Meckel’s diver-
ticula in preterminal ileum – usually presents with hemorrhage in
teenage years
■Rare diverticula – congenital giant colonic or duodenal diverticula
(usually present with hemorrhage).
■Associated diseases – very rare – scleroderma
■Usual presentations – note: diverticulitis and diverticular hemor-
rhage rarely occur simultaneously
■Diverticulitis – usually pain, typically left lower quadrant, occasion-
ally palpable mass and rebound (rare)
■Diverticular hemorrhage – painless bleeding without other signs or
symptoms
■Diverticula are never the cause of persistently guaiac positive stools
and/or chronic anemia; other causes must be consideredtests
Diverticulitis
■Basic tests
➣Elevated WBC common but sepsis rare
■Imaging tests
➣CT scan of abdomen usually shows focal colonic wall thickening,
stranding of mesenteric fat, and occasionally an abscess.
➣CT is the most helpful – use IV, PO and rectal contrast if colonic
diverticulitis is suspected
➣Plain abdominal radiographs – essentially useless but inexpen-
sive