Gastrointestinal Disorders

1
Gastrointestinal


Disorders
2
Disorders of Nutrition

• Alterations in Ingesting Digesting
  Absorbing Eliminating

3
Ingestion

• Anorexia
• Pica
• Nausea Nausea
• Esophageal Atresia
• Tracheoesopheal fistula

• Cleft lip/palate
• Anorexia Nervosa
• Pyloric Stenosis
• Projectile Vomiting

4
Maldigestion

• Lactic Deficiency
• Pancreatitis
• Cystic Fibrosis

5
Malabsorption

• Intestinal Parasites
• Gastrectomy Loss of Stomach as Reservoir
  for Food Dumping Syndrome Loss of Intrinsic
  Factor
• Celiac Disease (Sprue)
• Cholecystitis/Cholelithiasis
• Regional Enteritis (Crohns Disease)

6
Elimination

• Diarrhea Osmotic Changes Secretory Changes
  Mucosal Damage Altered Motility
• Crohns Disease
• Ulcerative Colitis

7
Basic Structure of the GI tract
PSNS
SNS
longitudinal muscle
Myenteric plexus
Circular muscle
Submucosal plexus
Submucosa
Lumen
8
Enteric Nervous System Influenced by ANS
PSNS
SNS
Pelvic nerves
NE
Ach
ENTERIC NERVOUS SYSTEM Myenteric
Submucosal
Smooth muscle
Secretory Cells
Endocrine Cells
Blood Vessels
9
Gastric Motility
LES
fundus
pylorus
receptive relaxation
Antrum
approx 3 contractions per minute
10
Control of Gastric Emptying
PSNS
SNS

-
GASTRIC EMPTYING
-
-
secretin
-
CCK
Duodenal acid
Duodenal fats
Duodenal hypertonicity
11
Small and Large Bowel Motility

• Small Intestine
• 2-4 hours to traverse
• Segmental contractions to mix
• Peristaltic waves to move forward
• Large Intestine
• Slow progression at 5-10 cm per hour
• Segmental contractions produce haustra
• 1-3 mass movements per day

12
Secretion in the Stomach

• Parietal Cells
• HCL
• Intrinsic Factor
• Chief Cells
• Pepsinogen
• Surface epithelia and mucous cells
• HCO3- and mucus

13
Control of Acid Secretion
Vagus Mast Cells G cells
Ach Histamine Gastrin
muscarinic receptor
H2 receptor
gastrin receptor
Gastric Parietal Cell
Acid Secretion
14
Secretion in the Small Intestine

• Secretions from Pancreas
• HCO3-, Proteases, Lipases, Amylases
• Secretion from Gallbladder
• Bile acids, pigment, phospholipid
• Secretions from intestinal epithelia
• Brush border enzymes

15
Brush Border Enzymes
Lactase lactose glucose, galactose Sucrase su
crose fructose, glucose Dextrinase cleaves
amylose branch points Glucoamylase
maltose glucoses
Only Monosaccharides are Absorbed
16
Digestion and Absorption of Proteins

• Pepsin 15 of peptide bonds broken
• Pancreatic proteases
• Trypsin
• Chymotrypsin
• Carboxypeptidases
• Brush Border
• Peptidases cleave into 1 to 4 aa chains

17
Digestion and Absorption of Fat

• Bile salts are amphipathic molecules that break
  up large fat globs into droplet
• Lipase are water soluble - only work at surface
  of droplet
• Triglycerides --------gt FFA and glycerol
• Bile forms micelles with FFA to keep soluble.
• FFA are lipid soluble so absorb directly

18
Reabsorption of Bile

• Bile is reabsorbed at terminal ileum
• Passive diffusion and active transport
• Transported to liver via portal blood
• ALL reabsorbed bile is taken up on first pass by
  liver
• Entire bile pool circulates 2 to 5 times per
  meal. 5-10 lost per day in stool

19
GI Disorders
20
Dysphagia

• Neuromuscular pharynx
• Stricture or tumor Progressive solid food
  dysphagia
• Achalasia esophageal motility disorder, loss of
  peristalsis in lower 2/3 plus impaired LES
  relaxation
• Mallory-Weiss syndrome mucosal tears at distal
  esophagus, bleeding, pain

21
Oropharyngeal vs Esophageal

• Nasal regurgitation
• Airway obstruction with eating
• Coughing when swallowing
• Immediate regurgitation
• Hoarse voice

• No airway distress
• Late regurgitation
• Chest pain _at_ meals
• Frequent heartburn
• Presence of collagen disease
• Presence of Left supraclavicular node

22
Dyspepsia

• Present with heartburn, indigestion, epigastric
  distress
• Up to 2/3 will have no identifiable cause
• One-half will have relief from placebo
• Symptom profile does not differentiate between
  GERD, PUD, and non-ulcer dyspepsia (functional)
• Physical exam is rarely helpful

23
Diagnosis

• NSAID suspect PUD and treat
• Helicobacter pylori urea breath test or biopsy
  during endoscopy
• GERD Trial of H2 therapy
• Functional may improve with agents that increase
  motility
• Zollinger-Ellison syndrome gastrin level

24
PUD with H. pylori

• H. pylori is nearly always a factor in non-NSAID
  peptic ulcer disease
• Conventional therapy with H2 blockers or H pump
  inhibitors has a 75-80 one-year recurrence rate
• Treatment for H. pylori reduced recurrence rate
  to less than 5

25
Acute Infectious Diarrhea
High fever? Bloody diarrhea?
YES
NO
Noninflammatory
Inflammatory
watery large volume periumbilical pain
small volume LLQ pain fecal leukocytes
Shigella, Salmonella, C. difficile, E. coli
(bad) Campylobacter, HIV- associated
Viral rotavirus, Norwalk S. aureus food
poisoning Giardia
Rehydrate, symptomatic
Culture and treat
26
Chronic Diarrhea Stool Studies

• Stool Osmolality normal gap lt 50
• Laxative screen Mg, PO4, SO4
• Fecal leukocytes Inflammatory disease
• Ova and parasites Giardia, cryptosporidium
• Fecal Fat analysis gt 10 g/24 hrs indicates
  malabsorption
• Fecal weight gt 1000 g is secretory

27
Osmotic Diarrhea Lactase Def.

• Incidence
• 90 of Asian Americans
• 95 of Native Americans
• 50 of Mexican Americans
• 60 of Jewish Americans
• 25 of other Caucasians
• DX empiric trial of lactose-free diet for two
  weeks

28
Inflammatory Bowel Disease

• Ulcerative Colitis
• Involves only the colon and rectum
• Mucosal layer is affected
• Hallmark is bloody diarrhea and lower abdominal
  cramps
• Associated with increased cancer risk after 8-10
  years of disease

29
Assess UC Disease Severity

• Number of stools per day
• Hematocrit
• Sed rate
• Albumin level

30
Crohn Disease

• Intermittent bouts of fever, diarrhea, and RLQ
  pain
• May have RLQ mass, tenderness
• Can affect any portion of GI tract
• 30 are small bowel only
• 50 are small and large bowel
• 15-20 are large bowel only

31
Crohn Disease

• Transmural process in the intestinal wall
  predisposes to fistula formation
• If suspected, obtain upper GI series with small
  bowel follow through plus either colonoscopy or
  barium enema
• Suggestive findings are ulcerations, strictures,
  and fistulas
• RX stop smoking, drugs similar to UC

32
Compare and Contrast CD UC

• Ulcerative ColitisContinuous ulcerationof
  mucosa of colonColon, rectum distalWatery
  diarrhea has mucus/pus may be bloody
  commonProned to develop colon carcinomarare
  abcess/fistula formation

• Crohns Disease Skip Lesions
  (granulomatous) Terminal ileum
  Diarrhea/Constipation Alternates Less
  Bloody Malignant Potential(not totally
  determined)
• Proned to Develop Abcesses Fistula
  formation

33
Motility Diarrhea IBS

• Irritable bowel syndrome is a chronic (gt3months)
  functional disorder with no identifiable
  pathology
• Fluctuations in stool frequency and consistency
  (no nocturnal diarrhea)
• Perceived abd distention, bloating, pain
• Often associated with anxiety or depression

34
IBS

• It is not IBS if fever, bloody stools, nocturnal
  diarrhea, or weight loss are present
• Consider checking CBC, sed rate, albumin, and
  stool for occult blood to rule out inflammatory
  disease, consider lactose-free trial.
• RX restrict caffeine, gas producing food, high
  fiber. Rx depression

35
Occult GI Bleeding

• Detected by FOBT worry colorectal CA
• Indicated for iron deficiency anemia in males or
  postmenopausal females
• Unless SS suggest Upper GI etiology (heartburn,
  dyspepsia PUD) start with colonoscopy (or barium
  enema)
• If no source, follow with endoscopy

36
Acute Abdominal Pain

• Tension spasm, associated with intense
  peristalsis (irritant, infection, obstruction)
• Ischemia intense constant pain (bowel
  strangulation, volvulus adhesion)
• Inflammation first localized to serosa covering
  inflamed part then extends to abdominal wall
  causing reflex muscle spasms (rigidity,
  involuntary guarding)

37
Assessment of the Pain

• Is it nongastric? consider aortic aneurysm,
  ectopic pregnancy, PID, kidney
• Is it an acute surgical abdomen?
• Involuntary guarding, rigidity
• Absent bowel sounds
• Is there shock

38
Localization of Abdominal Pain

• Stomach, duodenum mid epigastric
• Small bowel periumbilical
• Colon low abdomen, midline
• Rectum sacrum and perineum
• Gallbladder mid epigastric radiates to RUQ or
  right scapula
• Pancreas mid epigastric radiate to back
• Appendix RLQ, but variable

39
Bowel Obstruction

• Presentation
• Pain, distention, vomiting, obstipation
• Evaluation
• Flat and upright abdominal film
• Small bowel less urgent
• intestinal tube, decompression
• Large bowel urgent, danger of cecal perf
• immediate surgical consult

40
Types of Bowel Obstruction

• Mechanical Obstruction Adhesions
  Tumors Impaction Strangulated Hernia
  Volvulus Twisting Intussusception
  (telescoping)

• Functional Obstruction Bowel Manipulation
  (surgery) Narcotic Anesthesia
  Peritonitis

41
Itis from TOP to BOTTOM
itis Etiology Clinical Findings esophagitis ref
lux (GERD) - pain after meals -
heartburn gastritis -PUD ASA, ETOH -
epigastric pain H. pylori regional enteritis ?
Etiology - diarrhea with (Crohn) blood and
mucus ulcerative colitis ? Etiology - bloody
diarrhea
42
Itis from TOP to BOTTOM
itis Etiology Clinical Findings diverticulitis
low fiber diet low abdominal pain,
fever appendicitis obstruction - RLQ pain,
fever fecalith - rebound pain peritonitis per
foration - severe pain, ileus bowel ischemia -
guarding, rigid pancreatitis biliary disease -
pain to back, shock ETOH - high lipase, amylase
43
Itis from TOP to BOTTOM
itis Etiology Clinical Findings cholecystitis c
holelithiasis - RUQ pain -
steatorrhea hepatitis viral, acute ETOH -
jaundice, big liver - high AST, ALT -
flu-like symptoms
44
Appendicitis

• Etiology
• Obstruction by fecalith, inflammation
• Presentation
• RLQ pain (classic, but may be anywhere), NV,
  fever, diarrhea, RLQ tenderness
• Evaluation CBC, abdominal ultrasound
• RX immediate surgical consult

45
Diverticulitis

• Etiology
• Microperforation with peridiverticular
  inflammation
• Presentation
• Elderly with LLQ pain, severe constipation,
  nausea, fever
• Evaluation
• CBC, abd film, CT if peritoneal signs
• Rx NPO, antibiotics, IV fluids

46
Liver, biliary, and pancreatic anatomy
47
Acute Pancreatitis

• Etiology unknown
• Associated with ETOH, biliary disease
• Presentation
• Severe epigastric and back pain
• Evaluation
• CBC, glucose, calcium, electrolytes, amylase,
  lipase (renal studies)
• Severity index

48
Severity Scale Pancreatitis

• During first 48 hours
• HCT drop of gt10
• BUN rise gt5 mg/dl
• PaO2 lt 60
• Calcium lt 8 mg/dl
• Fluid sequestration of gt 6 liters

• Initially
• Age over 55
• WBC gt 16,000
• Blood glucose gt 200
• Base deficit gt 4
• Serum LDH gt350
• AST gt 250

49
Pancreatitis Severity
Mortality Rate
Number of criteria
1 16 40 100
0-2 3-4 5-6 7-8
50
Cholecystitis

• Etiology
• 95 associated with stone in cystic duct
• Presentation
• Often obese female, fever, RUQ pain with scapular
  or epigastric pain, colicky, NV
• Evaluation
• CBC, RUQ ultrasound, HIDA scan
• RX Prompt cholecystectomy

51
Steatorrhea

• Pancreatic steatorrhea
• gt 90 of exocrine function lost
• Bile salt deficiency
• decreased ileal reabsorption (Crohn)
• blocked secretion (cholestasis)
• Bacterial overgrowth syndromes
• stasis of small bowel contents
• Mucosal defects Celiac disease (sprue)

52
Jaundice

• Jaundice occurs with bilirubin level gt 3 mg/dl
  (normal 0.2-1.2)
• Increased RBC breakdown
• Impaired liver uptake of bilirubin
• Impaired excretion of bilirubin

53
Functions of the Liver

• Nutrient metabolism (glucose, protein, fat, fat
  soluble vitamins)
• Production of serum proteins and enzymes
  (albumin, clotting factors etc.)
• Detoxification of hormones, drugs
• Bile synthesis (conjugation of bilirubin)
• Urea synthesis

54
Structure of liver lobule
55
Manifestations of Liver Dysfunction

• Impaired protein synthesis
• bleeding (clotting factor deficiency)
• edema (hypoproteinemia)
• immune deficiency (substrate for antibody)
• Accumulation of toxins and hormones
• feminization (excess estrogens)
• poor metabolism of drugs
• spider nevi (estrogen)

56
Manifestations of Liver Dysfunction

• Inadequate bile synthesis
• increased bilirubin level
• jaundice
• Inadequate urea synthesis
• increased blood ammonia level (NH3)
• hepatic encephalopathy
• Release of marker enzymes into blood
• AST (SGOT)
• ALT (SGPT)

57
High Direct Bilirubin

• Hepatocellular injury
• hepatitis
• drugs
• hemochromatosis
• Alpha-1 antitrypsin deficiency
• Cholestasis
• stones, tumors, strictures
• cholangitis

58
Acute Hepatitis

• Etiology acute liver inflammation and cellular
  injury viral, toxic
• Presentation jaundice, anorexia, fatigue,
  diffuse abd discomfort, dark urine
• Evaluation History of viral or toxin exposure,
  AST, ALT, Alk phos, bilirubin, serology for viral
  hepatitis

59
Viral Hepatitis
Type A B(D) C E Transmission oral-fecal blood
and blood and oral-fecal body fluids body
fluids Risk contaminated sexual, IV sexual,
IV waterborne food Prognosis good more
severe 85 chronic ? 5 carrier BD
more severe
60
Acute Toxic Hepatitis

• Etiology exposure to hepatotoxin or its
  metabolite
• Evaluation No definitive tests
• history of exposure is important
• negative viral serology screen
• improvement after discontinuing drug
• if alcohol is the toxin, AST gt ALT, 21

61
Chronic Alcoholic Liver Disease

• Etiology chronic, heavy ETOH exposure
• Only 15-20 of alcoholics develop liver disease
• Men gt 4-6 drinks/day, Women gt 3-4/day
• Pathogenesis unknown
• Presentation
• fatty liver
• hepatitis
• cirrhosis

62
Cirrhosis of the Liver

• Fibrotic liver
• loss of hepatocellular functions
• obstruction to bloodflow from the gut
• Etiology
• Chronic alcohol use (most common)
• Biliary (obstruction in bile drainage)
• Postnecrotic (viral, toxic hepatitis)
• Cardiac (right heart failure, liver congestion)

63
Liver Cirrhosis
From GI tract
cell failure
jaundice bleeding low albumin -edema immune
deficient estrogen excess encephalopathy
Portal vein
To vena cava
portal hypertension ascites esophageal
varices hemorrhoids anorexia
Hepatic vein
64
Treatment Monitoring

• Abstinence from alcohol
• Restore nutrition (high protein diet unless
  hepatic encephalopathy)
• Monitor PT, AST, ALT, albumin, bilirubin
• Vitamin K
• Abnormal PT despite vitamin K indicates a
  severely compromised liver

65
Treatment Monitoring

• Ascites
• caput medusae flow outward from navel
• sodium restriction
• spironolactone
• monitor for spontaneous bacterial peritonitis
• If ascites is present, high likelihood of
  esophageal varices

66
Treatment Monitoring

• Hepatic Encephalopathy
• Altered mental status due to accumulation of
  toxins, including ammonia (NH3)
• Precipitated by GI bleed, drugs, increased
  shunting of blood around liver
• Monitor NH3 level
• lactulose
• withhold protein

67
Liver Cancer

• May and usually does have similar clinical
  manifestations to cirrhosis. Liver cancer is
  almost always metastatic. The survival rate s
  less than 5.

68
Balloon tamponade of esophageal varices
69
Study Well Do GREAT Next Week

• The End..