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
what is responsible for the absoprtion of 90% of all nutrients?
SI
where is Vit B and K absoprted?
colon
name the different types of diarrhea
osmotic
inflammatory/infectious/infiltrative
abrnomal GI motility
secretory
Osmotic diarrhea
- define
- causes and ex
- typical CM
- additional water is pulled into the GI tract
- something is pulling the water into the colon
- *anytime something is not digested/absorbed– it pulls water in
CAUSES
1) ingestion: antacids, laxatives, sugar free candies
2) maldigestion: pancreatic insuff, diassacch insufficency
3. Malabsoprtion: CHO malabsoprtion, congenital choridorrhea
CM:
- abdmoinal distention
- blaoting
- flautlence due to increased colonic gas production
Disorders of intestinal transit diarrhea
- define
- causes + ex
contents move through intetines too quickly for normal water absoprtion to occur
causes
1) rapid transit–insuff contact time: intestinal resection, hyperT, IBS-D
Secretory Diarrhea
- define
- causes + ex
- CM
epithelial cells lining the intestines actively secrete more water than they absorb–causing large volumes of fluid diarrhea and rapid dehydration
causes:
1) bacterial endotoxins: Vibrio cholerae, E. coli
2) Secretagogoues: bile acids, fatty acids, ethanol, prostaglandins, gastrin, calcitonin
CM:
- high volume (>1L/day) of watery diarrhea
- dehydration
- elect imabal
drugs that cause diarrhea
- Cholinesterase inhibitors
- Selective serotonin reuptake inhibitors
- Angiotensin II-receptor blockers
- Proton pump inhibitors
- Nonsteroidal anti-inflammatory
- Metformin
- Allopurinol
- Orlistat
- Lactulose
- Antacids–mag
- Rx’s for constipation
Exudative Diarrhea
-define
inflammatory
Causes:
1) increased passage of body fluids into lumen due to inflammatory intestinal mucosal damage–UC, CD
describe visceral pain
- patho? causes?
- ex
vague
dull
poorly localized
PATHO:
- inflammation ischemia or distention that causes it
- can start diffuse/midline–stemming from embryological bilateral innvervation of organs
EX:
-early appendicitis
-
describe parietal pain
- patho? causes?
- ex
sharp, localized
PATHO:
- parietal peritoneum inflammation or irritation
- complete involement of the parietal peritoneum
- pain can become more diffuse in advnaced dz
EX: -late stages of appendicitis: \+localized RLQ pain \+rebound tenderness \+rigidity
Describe referred pain
- patho/causes
- ex
Distant to orginial pathology
PATHO:
-related usually to embryological origins
EX:
MI presenting as epigastric pain
pancreatitis with back pain
reff pain to the shoulder is involving what nerve
irritation of phrenic nerve
stomach can have reff pain to?
shoulders
pancreas can have ref pain to?
left sohulder
back
GB can have ref pain to?
right subscapular area
list the types and ex for each of LGIB
- anatomic–diverticulosis
- Vascular–radiation induced, ischemic,
- neoplasm
- inflammatory—infectious or non infectius
* infectious: salmonella, shigella
* noninfectious: CD
what is there incr levels of if GIB?
BUN (blood urea nitrogen)
because there is protein in the blood— we digest it absorb it… increases our BUN
what is the typical lab work indication for a GIB?
BUN»»»
creatinine stays same
what anatomical parts are part of the UGIB
duodenum
stmoach
esophagus
intestinal obstruction
- define
- types
- MC in woh
- CM for small intestinal obstruction vs large
- MCC? adults and kids and then other general causes
any condition that prevents flow of chyme through the intestinal lumen
SIMPLE: mechanical blockage of the lumen
FUNCTIONAL: aka paralytic ileus
- failure of intestinal motlity
- often occurs after intestinal or abdominal surgery, pancreatitits, or hypokalemia
MC in adults
CM for Small intestinal ob:
- colicky (episodic) pains
- N/V— usually bilious
CM for large intestinal ob:
-hypogastric pain and distention
MCC in adults is:
- intestinal adhesions
- colin CA
MCC kids:
1. intussusuception
other general causes:
- hernias
- IBD–CD
- Diverticulitis
- Volvulus
- Impacted feces
intestinal adhesions
bans of firbous tissue in abd cavity that can come after abd or pelvic surgery
list the patho steps when an intestional obstruction occurs
gas and fluid build up proximal to obstruction–>distention that causes:
A) Pressure on diagraphm–>decr respiratory volume–>atelectasis–>pneumoina
B) Colicky abdominal pain–>N/V (decr food intake), decr nutrient abs, decr CHO reserves–KETOSIS–>loss of water and electrolytes–dehydration, hypok, hypochloremia,
when does acidosis start in a PT with intesitanl obstruction
late in the prcess or if the obstruction is low
when does alkalosis start in a PT with an intestinal obstruction
Early in process or if obstruction is high
Inflammatory bowel Dz
- general definiton for IBD
- general cause
Ulcerative colitis and Crohn’s dz
IBD: chronic, replasing, inflammator bowel disorders
RF genetics, environmental factors, alterations of epithelieal barrier functions, altered imune reactions to intestinal flora
CAUSE FOR BOTH: acute on chronic inflammatory response
- tissue immune cells activated
- cytokines + inflammation
- disrupt mucosal barrier
- T cell medicated response
* **this cycle continues
Ulcerative Colitis
- define
- locations MC
- dz is defined by
- where does it start
- general s/s
chronic inflamma dz that causes ulcerations of colonic mucosa
- begins in the rectum–>may extend proximally all the way to the entire colon
- defined by the LOCATION and severity
- intermittent periods of remision and exacerabtion
CM:
- diarrhea (10-20/day)
- urgency
- bloody stools **NOT SEEN IN CD*
- cramping
which has bloody stools– UC or CD>
UC
Chohn Dz -define -location -causes? -what can develop -
granulomatous colitis, ileocolitis or regional enteritis
- idiopathic inlflam disorder
- affects ANY part of GI tract
- casues SKIP LESIONS
-can cause fissues tht extend into the lymphatics**
s/s simialr to UC except no bloody stool
B12 anemia can develop bc ileum is point of origin always (ilitiis)
CD:
- site of origin
- patttern of progression
- thickness of inflammation
- s/s
- complications
- radiographic findings
- rick of colon CA
- surgery
- site of origin–terminal ileum
- patttern of progression–skip lesions/irregular
- thickness of inflammation–transmural (full thickness)
- s/s–crampy abd pain
- complications–fistulas, abscess, obstruction
- radiographic findings–string sign on barium X-ray
- rick of colon CA–slight increase
- surgery–for complications like strictures
UC:
- site of origin
- patttern of progression
- thickness of inflammation
- s/s
- complications
- radiographic findings
- rick of colon CA
- surgery
- site of origin–rectum
- patttern of progression–proximally contiguously
- thickness of inflammation–submucosa or mucosa
- s/s–bloody diarrhea
- complications–hemorrhage, toxic megacolon
- radiographic findings–lead pipe colon on barium XR
- rick of colon CA–marked incr (more than CD)
- surgery–curative
microscopic colitis
relatively common cause of nonbloody diarrhea
*chronic watery watery diarrhea–everyday
FORMS:
- Lymphocytic
- causd by inflammation due to invasion of lymphocytes (meds or infection can trigger) - Collagenous
- thick layer of collagen along with inflammation
IBS
- define
- characterixed by?
- F or M mC?
- assoc with?
- causes
- mainfestations
- s/s relieved?
disorder of brain-gut interaction
*recurrent abd pain with altered bowel habits
F»>M
assoc with:
- stress
- anxiety
- depression
- reduced quality of life
possible causes: bc really unsure what causes it
- visceral hypersensitivity or hyperalgesia
- abnormal intestinal permeability, motiltiy and secrertion
- postinflammatory (infectious or noninfectious)
- alteration in gut microbiota (dysbiosis)
- Food allergy/intolerance
- psychological factors
CM:
- lower abdominal pain or discomfort and bloating
- some s/s can be grouped:
1. diarrhea-predominant
2. constipation predominant
3. alternating C and D
s/s usually relieved with defication and DO NOT INTERFR WITH SLEEP ***
No cure—–
PT is waking up at night with s/s— what do you think of
chronic colitis
*not being woken up is more IBS
Diverticula define
-MC where
herniations of mucosa through the muscle layers of colon wall
- ESP sigmoid
- form at weak points in colon wall
diveticulosis
asymptomatic diverticular dz
diverticulitis
inflammatory stage of diverticulosis
-can cause fistula, bleeding, asbcess, obstruction perforation it it becomes complicated
appendicitis define causes complications tests?
inflammation of the vermiform appendix
causes: obstruction (fecaliths), FB, infection
periumbilical or epigastric pain
**rebound tenderness to RLQ
most serious complications: peritonitits, perf and abscess formation
Obturator: flexion + inteneral rotation of hip
Psoas: irritation to the iliopsoas group of hip flexsors with hip flexion or hyperextension
Rovsing: palpLLQ–>pain in RLQ
Mesenteric Vascular Insufficiency
aka?
-vasc supply to stomach and intestines comes from?
-typical CM?
ischemia
blood supply to the stomach and intestine:
- celiac artery
- superior and inferior mesenteric arteries
PAIN OUT OF PROPORTION TO `EXAM**
what is very commonly associated with UC
Primary Sclerosing Cholangitis
