GI: Small Intestine & Colorectal Flashcards
Congenital Duodenal Obstruction
- MC form?
- define
- what would you see on xray
- MC etiology?
MC=Duodenal atreisa
*complete absence of closure of a portion of the duodenum–>leading to gastric outlet obstruction
DOUBLE BUBBULE*
malformatoin can be a narrowing (stenosis), absence or malrotation of a portion of the intenstine
MCC=vascular compromise (ischemia) in utero
Duodenal atreisa is MC associted with?
downs syndrome + other congential abnormalities
Jejunoileal atresia MC associated with?
CF
intestinal Malrotation -define -locations? -dev during? CM
small intestine lacks normal posterior attachment (top)
**intestine twists upon itself–making a volvulus–and is defined by location: sigmoid, mid-gut, cecal, even gastric
*dev during neonatal period
define volvulus
- what can develop if left untreated
- which parts are MC invovled (adults vs kids)
- when a loop of intestine twists around itself
- mesentery that supports it–is obstructed–and if prolonged can lead to ischemia
- colonic twisting***
- twists at its mesenteric attachment site— why ishcemia can occur and MC leads to obstruction of vascular supply
untreated–perforation and/or ischemia
MC involved= sigmoid colon (75%) and cecum (25%)-adults
MC kids=midgut and ileum
what causes cecal volvulus
congenital lack of fixation of the right colon and tends to occur in younger patients
Meckel Diverticulum
- define
- what is the MC s/s?
- what can occur with it ?
(ileal)
* outpocketing of all layers of the small intestinal wall–MC ileum (lower intestines)
* congenital–left over from the yolk sac/umbilical cord
* pouch may contain ectopic gastric or pancreatic tissue–>that secretes digestive hormones–>leading to bleeding
“rule of 2s”
most are asympto
MC symptom is PANLESS rectcal bleeding
intestinal obstruction, intussusception and volvulus can occur
in adults may cause diverticulutis
MC congenital anomaly of the GI tract!!!****
Rule of two
- list them (7)
- for what dz
Mickel Diverticulum 2% of the population 2x more common in males 2 years MC age at presentation 2% symptopatic 2 inches in length 2 types of ectopic tissue (gastric or pancreatic) 1/2 present before age 2--- the rest usually in first 2 decades life
what is the MC congenital defect of the GI tract?
Meckel Diverticulum
Intussusception
- define
- MC where/how
- can lead to if not tx?
- typical CM buzzword?
telescoping (invagination) of a proximal segment of intestine into a distal segment— causing obstruction
MC occurs at the ileocolic junction–>ileum telescopes into the cecum and part of the ascending colon by collapsing through the ileocecal valve
can lead to: bleeding, necrosis, bowel perforation if not treated
blood supply compromise obstructoin–>ischemia–>bleeding–>necrosis–>perforation
CM– currant jelly stools. +abd pain +irritability +vomiting q
what is the MCC of bowel obstruction in children 6MO-4 years
intussuscpetion
what is meconium
substance that fills the intestine before birth
-thick black and tarry looking
meconim ileus assoc with?
CF–20%
wht is more severe: meconium ileus or meconium plug
ileus
meconium ileus
- what is it
- types
meconium causes intestinal obstruction because the it is extra thicker and stickier than normal–cannot pass–lads to ischemia
- extra thick secretions from CF creates thicker meconium–gets stuck in terminal ileum–peristalsis fails to propel this thru–becomes impacted
- small intestine will dilate since impacting is in terminal ileum–distention/backup into SI
- large intestines will appear collapsed–since cannot propel forward into LI
types:
1. simple
2. complex: medical emergency***** it is so plugged it cannot be moved and ischemia occurs
Meconium plug syndorme
transiet
think of it like a fecal impaction but for babies
*delayed passage of meconium with intestianl dilation
**not as serious as meconium ileum– this is transient and will pass with time or laxative
distal intestinal obstruction syndrome
-anatomic location of obstruction
characterized by complete or incomplete intestinal obstruction of viscid fecal accumulation in the terminal ileum and proximal colon
define aganglionic
NS innervating a certain part of the colon is not there– leads to colon enlargement
Hirschsprung DZ
- define/also called?
- MC affects what area
- tx
also called: congenital aganglionic megacolon
**functional (secondary to motility issue) “obstruction” of the colon
“obstruction” aka pseudoobstruction bc something is not physically blocking the colon it is just extremely enlarged because the portion below the swollen colon lacks NS innervation so it cannot perform peristalsis
- absecence of PSYMP nervous system intrinsic ganglionic cells— this is needed for normal peritalsis
- abnormally innervated colon impairs fecal movements–>colon obstruction and distention
MC affects the rectum—- narrowed rectum and swollen sigmoid colon****
tx: surgrey– remove affected part of the bowel
Anorectal malformations
- name them
- associated with
- when are they IDed
anorectal stenosis
imperforate anus–>no butthole on outside
anorectcal atresia–>ends in blind pouch
rectcal atresia–>ends in blind pouch
- assoc with other congenital developmental anomalies
- IDed in routine physical exam
- tx with dilations for stenosis or surgery for other malformations
celiac dz
-what is it
-what grains?
-
autoimmune dz
- damages small intestinal villous epithelium when gluten ingested
- GLUTEN=protein component in wheat rye malt and barley
*dietary, genetic and immunologic factors
*
patho steps for celiac dz—
gluten intolerance–>T cell, AB and complement activated:
A: PRIMARY EFFECTS: direct villus injury–>decr surface area–>inflammatory enteritis–>OSMOTIC diarrhea–>SECRETORY diarrhea–>decr absoprtion of proteins and decr electrolytes
B: SECONDARY EFFECTS: mucosal damage of proximal bowel–>decr intestinal homrones–>decr pancreatic function–>decr CHO absoprtion, protein absoprtion and fat absoprtion–>malnutriotn
Constipation -deinfe primary secondary two basic etiologies
infreq or difficlt defecation
Primary:
- normal transit functional
- slow transit
- pelvic floor or outlet dysfunction
Secondary:
-caused by many diff factors: diet, medications, dzs, aging
<3 BMs/weeek ***
- disordered movement–of the stool thru colon/anus/rectum
- slow colonic transit: dz, drugs SE, etc
fecal impaction
MC where
large hard mass of stool that gets stuck so badly in colon or rectum that PT cannot push it out
- can be very severe
- more common in older aduts— imp cause of abdominal pain in elderly
*MC in distal rectum
name some drugs that cause constpation
name motor disorders that can cause constipation
outlet delay dz causing constpation?
verapamil
opioids
DM
colorectcal CA
hypothryoid
Hirschsprung’s dz
diarrhea
- define
- acute
- chronic
- mild
- moderate
- severe
- large volume vs small volume— what is the cause for each
- rapid transit of bowel contents so there is insufficent time for reabsoprtion of water to firm feces
- stools=loose and liquid
- passed more frequently (usually>3/day)
- acute: <2 weeks (usually infectious)
- chronic: >2 weeks, usually >4 weeks
- Mild: 3 or less/ day
- mod: 4+ stool/day with local s/s: abdom cramps, nausea, tenesmus
- severe: 4+/day with systemic symtpms: fever, chills, dehydration
large volume: excess amt of water or secretions or both in the intestines
small volume: usually results from excessive intestinal motility