patho ch 38 39 digestive system

Structure, Function, and Alterations Structure, Function, and Alterations of the Digestive Systemof the Digestive System

Chapters 38 & 39Chapters 38 & 39

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Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc.Mosby items and derived items © 2010, 2006 by Mosby, Inc., an affiliate of Elsevier Inc. 22

Gastrointestinal TractGastrointestinal Tract MouthMouth EsophagusEsophagus StomachStomach Small intestineSmall intestine Large intestineLarge intestine RectumRectum Anus Anus


Gastrointestinal Tract Functions: Gastrointestinal Tract Functions: OverviewOverview

Breaks down ingested foodBreaks down ingested food Prepares food for uptake by the bodyPrepares food for uptake by the body’’s cellss cells Provides body waterProvides body water Eliminates wastes Eliminates wastes Controlled by hormones and the autonomic Controlled by hormones and the autonomic

nervous system (except for chewing, nervous system (except for chewing, swallowing, and defecation) swallowing, and defecation)

Video of digestion

http://www.youtube.com/watch?v=Z7xKYNz9AS0


Gastrointestinal TractGastrointestinal Tract


StomachStomach


Gastric MotilityGastric Motility SwallowingSwallowing GastrinGastrin CholecystokininCholecystokinin MotilinMotilin Secretin Secretin Gastric emptyingGastric emptying


Gastric SecretionGastric Secretion The stomach secretes large volumes of The stomach secretes large volumes of

gastric juicesgastric juices MucusMucus AcidAcid EnzymesEnzymes HormonesHormones Intrinsic factorIntrinsic factor Gastroferrin Gastroferrin


Gastric Pits and Gastric GlandsGastric Pits and Gastric Glands


Gastric SecretionGastric Secretion Phases of gastric secretionPhases of gastric secretion

Cephalic phaseCephalic phase Gastric phaseGastric phase Intestinal phaseIntestinal phase

Enzymes, Proteins and Carbohydrates

http://www.youtube.com/watch?v=vFiavuyk31s


Small IntestineSmall Intestine 5 to 6 meters long5 to 6 meters long Three segmentsThree segments

DuodenumDuodenum Jejunum-last sight for nutrient absorption Jejunum-last sight for nutrient absorption IleumIleum

• Ileocecal valveIleocecal valve PeritoneumPeritoneum

Peritoneal cavityPeritoneal cavity


Small IntestineSmall Intestine Muscle layersMuscle layers

Outer—longitudinalOuter—longitudinal Inner—circular Inner—circular

Mucosal folds (plica)Mucosal folds (plica) Villi Villi MicrovilliMicrovilli

Brush borderBrush border Lamina propriaLamina propria LactealLacteal


Intestinal Digestion and Intestinal Digestion and AbsorptionAbsorption

Hydrochloric acidHydrochloric acid PepsinPepsin Intestinal enzymes Hormones and their actions on small intestineHormones and their actions on small intestine

Peptide YY – delays emptyingPeptide YY – delays emptying Secretin – stimulates pancreasSecretin – stimulates pancreas Enteroglucagon – insulin release, lipolysis, ketogenesisEnteroglucagon – insulin release, lipolysis, ketogenesis Pancreatic polypeptide – decreases pancreatic bicarb, Pancreatic polypeptide – decreases pancreatic bicarb,

enzymesenzymes

http://www.youtube.com/watch?v=URHBBE3RKEs&feature=relmfu


Large IntestineLarge Intestine CecumCecum AppendixAppendix ColonColon

AscendingAscending TransverseTransverse DescendingDescending SigmoidSigmoid

RectumRectum AnusAnus


Large IntestineLarge Intestine


Intestinal BacteriaIntestinal Bacteria Stomach environment is relatively sterile Stomach environment is relatively sterile

because of secreted stomach acidbecause of secreted stomach acid Bile acid secretion, motility, and antibody Bile acid secretion, motility, and antibody

production keep bacterial numbers in the production keep bacterial numbers in the duodenum to a minimumduodenum to a minimum

A low concentration of aerobes in the jejunumA low concentration of aerobes in the jejunum Anaerobic bacteria distal to the ileocecal Anaerobic bacteria distal to the ileocecal

valvevalve Anaerobes are 95% of the fecal flora in the colonAnaerobes are 95% of the fecal flora in the colon


Accessory Organs of DigestionAccessory Organs of Digestion


Hepatic Portal CirculationHepatic Portal Circulation


Secretion of BileSecretion of Bile Alkaline, bitter-tasting, yellowish green fluid Alkaline, bitter-tasting, yellowish green fluid

that contains bile salts, cholesterol, bilirubin, that contains bile salts, cholesterol, bilirubin, electrolytes, and waterelectrolytes, and water

Formed by hepatocytes and secreted into the Formed by hepatocytes and secreted into the bile canaliculibile canaliculi

Enterohepatic circulationEnterohepatic circulation Recycling of bile saltsRecycling of bile salts


Vascular and Hematologic Vascular and Hematologic Liver FunctionsLiver Functions

Blood storageBlood storage Bacterial and foreign particle removalBacterial and foreign particle removal Synthesizes clotting factorsSynthesizes clotting factors Produces bile to absorb fat-soluble vitaminsProduces bile to absorb fat-soluble vitamins Metabolizes fatsMetabolizes fats


Vascular and Hematologic Vascular and Hematologic Liver FunctionsLiver Functions

Metabolizes proteinsMetabolizes proteins Metabolizes carbohydratesMetabolizes carbohydrates Metabolic detoxificationMetabolic detoxification Storage of minerals and vitaminsStorage of minerals and vitamins


GallbladderGallbladder A sac-like organ that lies on the inferior A sac-like organ that lies on the inferior

surface of the liversurface of the liver Function is to store and concentrate bile Function is to store and concentrate bile

between mealsbetween meals Gallbladder holds about 90 ml of bileGallbladder holds about 90 ml of bile


Exocrine PancreasExocrine Pancreas Composed of acini and networks of ducts that Composed of acini and networks of ducts that

secrete enzymes and alkaline fluids to assist secrete enzymes and alkaline fluids to assist in digestionin digestion

Pancreatic ductPancreatic duct Ampulla of VaterAmpulla of Vater


Exocrine PancreasExocrine Pancreas


Exocrine PancreasExocrine Pancreas SecretionsSecretions

Potassium, sodium, bicarbonate, magnesium, Potassium, sodium, bicarbonate, magnesium, calcium, and chloridecalcium, and chloride

EnzymesEnzymes Trypsinogen, chymotrypsinogen, and Trypsinogen, chymotrypsinogen, and

procarboxypeptidaseprocarboxypeptidase Trypsin inhibitorTrypsin inhibitor Pancreatic Pancreatic αα-amylase-amylase Pancreatic lipasePancreatic lipase


Aging and the Digestive FunctionAging and the Digestive Function Tooth enamel and dentin wear downTooth enamel and dentin wear down Teeth are lostTeeth are lost Periodontal diseasePeriodontal disease Gum recessionGum recession Osteoporotic bone changesOsteoporotic bone changes Number of taste buds declineNumber of taste buds decline Sense of smell diminishes Sense of smell diminishes Salivary secretion decreasesSalivary secretion decreases Decreased esophageal and gastric motilityDecreased esophageal and gastric motility


Clinical Manifestations of Clinical Manifestations of Gastrointestinal DysfunctionGastrointestinal Dysfunction

AnorexiaAnorexia A lack of desire to eat despite physiologic stimuli A lack of desire to eat despite physiologic stimuli

that would normally produce hungerthat would normally produce hunger VomitingVomiting

The forceful emptying of the stomach and The forceful emptying of the stomach and intestinal contents through the mouthintestinal contents through the mouth

Several types of stimuli initiate the vomiting reflexSeveral types of stimuli initiate the vomiting reflex



NauseaNausea A subjective experience associated with a number of A subjective experience associated with a number of

conditionsconditions Common symptoms: hypersalivation and tachycardiaCommon symptoms: hypersalivation and tachycardia

RetchingRetching Nonproductive vomitingNonproductive vomiting

Projectile vomitingProjectile vomiting Spontaneous vomiting that does not follow nausea or Spontaneous vomiting that does not follow nausea or

retching retching



ConstipationConstipation Infrequent or difficult defecationInfrequent or difficult defecation PathophysiologyPathophysiology

• Neurogenic disorders, functional or mechanical Neurogenic disorders, functional or mechanical conditions, low-residue diet, sedentary lifestyle, conditions, low-residue diet, sedentary lifestyle, excessive use of antacids, changes in bowel habitsexcessive use of antacids, changes in bowel habits



DiarrheaDiarrhea Increased frequency of bowel movementsIncreased frequency of bowel movements Increased volume, fluidity, weight of the fecesIncreased volume, fluidity, weight of the feces

• May be protectiveMay be protective Major mechanisms of diarrheaMajor mechanisms of diarrhea

• Osmotic diarrheaOsmotic diarrhea• Secretory diarrheaSecretory diarrhea• Motility diarrheaMotility diarrhea



Systemic effects of GI dysfunctionSystemic effects of GI dysfunction Manifestations of diarrheaManifestations of diarrhea

• Dehydration, electrolyte imbalance, metabolic acidosis, and Dehydration, electrolyte imbalance, metabolic acidosis, and weight lossweight loss

Manifestations of acute bacterial or viral infectionManifestations of acute bacterial or viral infection• Fever, with or without cramping pain Fever, with or without cramping pain

Manifestations of inflammatory bowel diseaseManifestations of inflammatory bowel disease• Fever, cramping pain, bloody stools Fever, cramping pain, bloody stools

Manifestations of malabsorption syndromesManifestations of malabsorption syndromes• Steatorrhea (fat in the stools) and diarrheaSteatorrhea (fat in the stools) and diarrhea



Abdominal painAbdominal pain A symptom of a number of GI disordersA symptom of a number of GI disorders Parietal painParietal pain Visceral painVisceral pain Referred painReferred pain

Biochemical mediators of the inflammatory Biochemical mediators of the inflammatory response response (histamine, bradykinin, and (histamine, bradykinin, and serotonin) serotonin) stimulate organic nerve endings stimulate organic nerve endings producing abdominal pain producing abdominal pain



GI bleedingGI bleeding Upper GI bleedingUpper GI bleeding

• Esophagus, stomach, or duodenumEsophagus, stomach, or duodenum Lower GI bleedingLower GI bleeding

• Below the ligament of Treitz, or bleeding from the Below the ligament of Treitz, or bleeding from the jejunum, ileum, colon, or rectumjejunum, ileum, colon, or rectum

HematemesisHematemesis HematocheziaHematochezia MelenaMelena Occult bleedingOccult bleeding


Disorders of MotilityDisorders of Motility DysphagiaDysphagia

Difficulty swallowingDifficulty swallowing TypesTypes

• Mechanical obstructionsMechanical obstructions• Functional obstructionsFunctional obstructions

AchalasiaAchalasia• Denervation of smooth muscle in the esophagus and Denervation of smooth muscle in the esophagus and

lower esophageal sphincter relaxationlower esophageal sphincter relaxation


Disorders of MotilityDisorders of Motility Gastroesophageal reflux disease (GERD)Gastroesophageal reflux disease (GERD)

The reflux of chyme from the stomach to the esophagusThe reflux of chyme from the stomach to the esophagus If GERD causes inflammation of the esophagus, it is called If GERD causes inflammation of the esophagus, it is called

reflux esophagitisreflux esophagitis A normal functioning lower esophageal sphincter maintains A normal functioning lower esophageal sphincter maintains

a zone of high pressure to prevent chyme refluxa zone of high pressure to prevent chyme reflux Conditions that increase abdominal pressure can contribute Conditions that increase abdominal pressure can contribute

to GERD to GERD ManifestationsManifestations

• Heartburn, regurgitation of chyme, and upper abdominal Heartburn, regurgitation of chyme, and upper abdominal pain within 1 hour of eatingpain within 1 hour of eating


Gastroesophageal Reflux DiseaseGastroesophageal Reflux Disease


Hiatal HerniaHiatal Hernia


Disorders of MotilityDisorders of Motility Intestinal obstruction and ileusIntestinal obstruction and ileus

An intestinal obstruction is any condition that An intestinal obstruction is any condition that prevents the flow of chyme through the intestinal prevents the flow of chyme through the intestinal lumen or failure of normal intestinal motility in the lumen or failure of normal intestinal motility in the absence of an obstructing lesionabsence of an obstructing lesion

An ileus is an obstruction of the intestinesAn ileus is an obstruction of the intestines ManifestastionsManifestastions

• Colicky pain, vomiting, distention, hypovolemia, Colicky pain, vomiting, distention, hypovolemia, metabolic acidosismetabolic acidosis


GastritisGastritis Inflammatory disorder of the gastric mucosaInflammatory disorder of the gastric mucosa Acute gastritisAcute gastritis

H. pylori,H. pylori, NSAIDs NSAIDs Chronic gastritisChronic gastritis

Chronic fundal gastritisChronic fundal gastritis Chronic antral gastritisChronic antral gastritis

• Signs and symptoms of chronic gastritis often do not Signs and symptoms of chronic gastritis often do not correlate with the severity of the disease correlate with the severity of the disease


Peptic Ulcer DiseasePeptic Ulcer Disease A break or ulceration in the protective A break or ulceration in the protective

mucosal lining of the lower esophagus, mucosal lining of the lower esophagus, stomach, or duodenumstomach, or duodenum

Acute and chronic ulcersAcute and chronic ulcers SuperficialSuperficial

Erosions Erosions DeepDeep

True ulcersTrue ulcers


Peptic Ulcer DiseasePeptic Ulcer Disease Duodenal ulcersDuodenal ulcers

Most common of the peptic ulcersMost common of the peptic ulcers Developmental factorsDevelopmental factors

• H. pyloriH. pylori infection infection Toxins and enzymes that promote inflammation and Toxins and enzymes that promote inflammation and

ulcerationulceration• Hypersecretion of stomach acid and pepsinHypersecretion of stomach acid and pepsin• Use of NSAIDsUse of NSAIDs• High gastrin levelsHigh gastrin levels• Acid production by cigarette smokingAcid production by cigarette smoking


Gastric UlcerGastric Ulcer Tends to develop in the antral region of the Tends to develop in the antral region of the

stomach, adjacent to the acid-secreting stomach, adjacent to the acid-secreting mucosa of the bodymucosa of the body

PathophysiologyPathophysiology The primary defect is an increased mucosal The primary defect is an increased mucosal

permeability to hydrogen ionspermeability to hydrogen ions Gastric secretion is normal or less than normalGastric secretion is normal or less than normal


Stress UlcerStress Ulcer Stress ulcer is a peptic ulcer that is related to Stress ulcer is a peptic ulcer that is related to

severe illness, neural injury, or systemic severe illness, neural injury, or systemic traumatrauma Ischemic ulcersIschemic ulcers Cushing ulcersCushing ulcers

• Ulcers that develop as a result of a burn injuryUlcers that develop as a result of a burn injury ManifestastionsManifestastions

• Bleeding most commonBleeding most common


MalabsorptionMalabsorption Syndromes Syndromes Inadequate digestionInadequate digestion Pancreatic insufficiencyPancreatic insufficiency Lactase deficiencyLactase deficiency Bile salt deficiencyBile salt deficiency Gluten-sensitive enteropathyGluten-sensitive enteropathy


Inflammatory Bowel DiseasesInflammatory Bowel Diseases Chronic, relapsing inflammatory bowel Chronic, relapsing inflammatory bowel

disorders of unknown origindisorders of unknown origin GeneticsGenetics Alterations of epithelial barrier functionsAlterations of epithelial barrier functions Immune reactions to intestinal floraImmune reactions to intestinal flora Abnormal T-cell responsesAbnormal T-cell responses


Ulcerative ColitisUlcerative Colitis Chronic inflammatory disease that causes ulceration of the Chronic inflammatory disease that causes ulceration of the

colonic mucosa colonic mucosa Sigmoid colon and rectumSigmoid colon and rectum

Suggested causesSuggested causes Infectious, immunologic (anticolon antibodies), dietary, Infectious, immunologic (anticolon antibodies), dietary,

genetic (supported by family studies and identical twin genetic (supported by family studies and identical twin studies)studies)

Symptoms - diarrhea (10-20/day), bloody stools, crampsSymptoms - diarrhea (10-20/day), bloody stools, cramps TreatmentTreatment

Broad-spectrum antibiotics and steroidsBroad-spectrum antibiotics and steroids Immunosuppressive agentsImmunosuppressive agents SurgerySurgery

Increased colon cancer risk demonstratedIncreased colon cancer risk demonstrated


Crohn DiseaseCrohn Disease Granulomatous colitis, ileocolitis, or regional enteritisGranulomatous colitis, ileocolitis, or regional enteritis Idiopathic inflammatory disorder; affects any part of the Idiopathic inflammatory disorder; affects any part of the

digestive tract, from mouth to anusdigestive tract, from mouth to anus Difficult to differentiate from ulcerative colitisDifficult to differentiate from ulcerative colitis

Similar risk factors and theories of causationSimilar risk factors and theories of causation Causes Causes ““skip lesionsskip lesions”” Ulcerations can produce longitudinal and transverse Ulcerations can produce longitudinal and transverse

inflammatory fissures that extend into the lymphaticsinflammatory fissures that extend into the lymphatics Anemia may result due to malabsorption of vitamin BAnemia may result due to malabsorption of vitamin B1212 and folic and folic

acidacid Treatment is similar to ulcerative colitisTreatment is similar to ulcerative colitis


Diverticular Disease of the ColonDiverticular Disease of the Colon DiverticulaDiverticula

Herniations of mucosa through the muscle layers Herniations of mucosa through the muscle layers of the colon wall, especially the sigmoid colonof the colon wall, especially the sigmoid colon

DiverticulosisDiverticulosis Asymptomatic diverticular diseaseAsymptomatic diverticular disease

DiverticulitisDiverticulitis The inflammatory stage of diverticulosisThe inflammatory stage of diverticulosis

ManifestationsManifestations Low abdominal pain, diarrhea, constipation, fever, Low abdominal pain, diarrhea, constipation, fever,

leukocytosisleukocytosis


AppendicitisAppendicitis Inflammation of the vermiform appendix Inflammation of the vermiform appendix Possible causesPossible causes

Obstruction, ischemia, increased intraluminal Obstruction, ischemia, increased intraluminal pressure, infection, ulceration, etc.pressure, infection, ulceration, etc.

ManifestationsManifestations Epigastric and right lower quadrant pain, rebound Epigastric and right lower quadrant pain, rebound

tendernesstenderness Nausea, vomiting, fever, leukocytosisNausea, vomiting, fever, leukocytosis

Most serious complication is peritonitisMost serious complication is peritonitis


Vascular InsufficiencyVascular Insufficiency Blood supply to the stomach and intestineBlood supply to the stomach and intestine

Celiac axisCeliac axis Superior and inferior mesenteric arteriesSuperior and inferior mesenteric arteries Two of three must be compromised to cause Two of three must be compromised to cause

ischemiaischemia Mesenteric venous thrombosisMesenteric venous thrombosis Acute occlusion of mesenteric artery blood Acute occlusion of mesenteric artery blood

flowflow Chronic mesenteric insufficiencyChronic mesenteric insufficiency


ObesityObesity Obesity is an increase in body fat massObesity is an increase in body fat mass

Body fat index >30Body fat index >30 A major cause of morbidity, death, and A major cause of morbidity, death, and

increased health care costsincreased health care costs Risk factor for many diseases and conditionsRisk factor for many diseases and conditions


ObesityObesity HypothalamusHypothalamus Hormones that control appetite and weightHormones that control appetite and weight

Insulin, ghrelin, peptide YY, leptin, adiponectin, Insulin, ghrelin, peptide YY, leptin, adiponectin, and resistinand resistin

Leptin resistanceLeptin resistance HyperleptinemiaHyperleptinemia


Anorexia Nervosa and Anorexia Nervosa and Bulimia NervosaBulimia Nervosa

Anorexia nervosaAnorexia nervosa Person has poor body image disorder and refuses Person has poor body image disorder and refuses

to eatto eat Person can lose 25% to 30% of ideal body weight Person can lose 25% to 30% of ideal body weight

due to fat and muscle depletiondue to fat and muscle depletion Can lead to starvation-induced cardiac failureCan lead to starvation-induced cardiac failure In females, characterized by absence of three In females, characterized by absence of three

consecutive menstrual periodsconsecutive menstrual periods Binge eating/purgingBinge eating/purging



Bulimia nervosaBulimia nervosa Body weight remains near normal but with Body weight remains near normal but with

aspirations for weight lossaspirations for weight loss FindingsFindings

• Recurrent episodes of binge eatingRecurrent episodes of binge eating• Self-induced vomitingSelf-induced vomiting• Two binge-eating episodes per week for at least 3 monthsTwo binge-eating episodes per week for at least 3 months• Fasting to oppose the effect of binge eating, or excessive Fasting to oppose the effect of binge eating, or excessive

exerciseexercise

Continual vomiting of acidic chyme can cause Continual vomiting of acidic chyme can cause pitted teeth, pharyngeal and esophageal pitted teeth, pharyngeal and esophageal inflammation, and tracheoesophageal fistulaeinflammation, and tracheoesophageal fistulae

Overuse of laxative can cause rectal bleedingOveruse of laxative can cause rectal bleeding



StarvationStarvation Decreased caloric intake leading to weight lossDecreased caloric intake leading to weight loss Short-term starvationShort-term starvation

• Glycogenolysis Glycogenolysis • GluconeogenesisGluconeogenesis

Long-term starvationLong-term starvation• Marasmus - inadequate intake of both Marasmus - inadequate intake of both protein and and

calories• Kwashiorkor - inadequate intake of protein but adequate Kwashiorkor - inadequate intake of protein but adequate

(or at least not starvation level) (or at least not starvation level) caloric intake

http://everything2.com/title/protein

http://everything2.com/title/calories

http://everything2.com/title/caloric+intake


Manifestations of Liver DiseaseManifestations of Liver Disease Portal hypertensionPortal hypertension AscitesAscites Hepatic-encephalopathyHepatic-encephalopathy Jaundice-someone who is jaundice over Jaundice-someone who is jaundice over

the entire body is called ictoricthe entire body is called ictoric Hepatorenal syndromeHepatorenal syndrome


Liver DisordersLiver Disorders Portal hypertensionPortal hypertension

Abnormally high blood pressure in the portal venous system due to Abnormally high blood pressure in the portal venous system due to resistance to portal blood flow resistance to portal blood flow

• PrehepaticPrehepatic• IntrahepaticIntrahepatic• Posthepatic Posthepatic

ConsequencesConsequences• VaricesVarices

Lower esophagus, stomach, rectumLower esophagus, stomach, rectum• SplenomegalySplenomegaly• AscitesAscites• Hepatic encephalopathyHepatic encephalopathy


Hepatic EncephalopathyHepatic Encephalopathy

Accumulation of toxins related to liver failure Accumulation of toxins related to liver failure cause disruption of neurotransmissioncause disruption of neurotransmission Ammonia-bacterial urease acting on gut proteinsAmmonia-bacterial urease acting on gut proteins Neurotoxins: result from hepatic failureNeurotoxins: result from hepatic failure

SymptomsSymptoms Personality changesPersonality changes ConfusionConfusion Memory lossMemory loss Stupor, coma, deathStupor, coma, death


Liver DisordersLiver Disorders Jaundice (icterus)Jaundice (icterus)

Obstructive jaundiceObstructive jaundice• Extrahepatic obstructionExtrahepatic obstruction• Intrahepatic obstructionIntrahepatic obstruction

Hemolytic jaundice Hemolytic jaundice • Prehepatic jaundicePrehepatic jaundice• Excessive hemolysis of red blood cells or absorption of a Excessive hemolysis of red blood cells or absorption of a

hematomahematoma


Viral HepatitisViral Hepatitis Systemic viral disease that primarily affects Systemic viral disease that primarily affects

the liverthe liver Hepatitis AHepatitis A

• Formally known as infectious hepatitisFormally known as infectious hepatitis Hepatitis BHepatitis B

• Formally known as serum hepatitisFormally known as serum hepatitis Hepatitis C, D, E, GHepatitis C, D, E, G


Hepatitis AHepatitis A Can be found in the feces, bile, and sera of Can be found in the feces, bile, and sera of

infected individualsinfected individuals Usually transmitted by the fecal-oral routeUsually transmitted by the fecal-oral route Risk factorsRisk factors

Crowded, unsanitary conditionsCrowded, unsanitary conditions Food and water contaminationFood and water contamination


Hepatitis BHepatitis B Transmitted through contact with infected Transmitted through contact with infected

blood, body fluids, contaminated needlesblood, body fluids, contaminated needles Maternal transmission if the mother is Maternal transmission if the mother is

infected during the third trimesterinfected during the third trimester Hepatitis B vaccine prevents transmission Hepatitis B vaccine prevents transmission

and development of hepatitis Band development of hepatitis B


Hepatitis CHepatitis C Responsible for most cases of post-Responsible for most cases of post-

transfusion hepatitistransfusion hepatitis Also implicated in infections related to IV drug Also implicated in infections related to IV drug

useuse 50% to 80% of hepatitis C cases result in 50% to 80% of hepatitis C cases result in

chronic hepatitischronic hepatitis


HepatitisHepatitis Hepatitis DHepatitis D

Depends on hepatitis B for replication Depends on hepatitis B for replication Hepatitis EHepatitis E

Fecal-oral transmissionFecal-oral transmission Developing countriesDeveloping countries

Hepatitis GHepatitis G Recently discoveredRecently discovered Parenterally and sexually transmittedParenterally and sexually transmitted


CirrhosisCirrhosis Irreversible inflammatory disease that Irreversible inflammatory disease that

disrupts liver function and even structuredisrupts liver function and even structure Decreased hepatic function from nodular and Decreased hepatic function from nodular and

fibrotic tissue synthesis (fibrosis)fibrotic tissue synthesis (fibrosis) Biliary channels become obstructed and Biliary channels become obstructed and

cause portal hypertension; due to the cause portal hypertension; due to the hypertension, blood shunted away from the hypertension, blood shunted away from the liver, and a hypoxic necrosis developsliver, and a hypoxic necrosis develops


CirrhosisCirrhosis

AlcoholicAlcoholic Oxidation of alcohol damages hepatocytesOxidation of alcohol damages hepatocytes

Biliary (bile canaliculi)Biliary (bile canaliculi) Cirrhosis begins in bile canaliculi and ductsCirrhosis begins in bile canaliculi and ducts Primary biliary cirrhosis (autoimmune)Primary biliary cirrhosis (autoimmune) Secondary biliary cirrhosis (obstruction)Secondary biliary cirrhosis (obstruction)

PostnecroticPostnecrotic Consequence of chronic diseaseConsequence of chronic disease


Disorders of the PancreasDisorders of the Pancreas PancreatitisPancreatitis

Inflammation of the pancreasInflammation of the pancreas Associated with several clinical disorders (alcohol Associated with several clinical disorders (alcohol

intake and cholelithiasis)intake and cholelithiasis)• Caused by injury or damage to pancreatic cells and ducts, Caused by injury or damage to pancreatic cells and ducts,

causing a leakage of pancreatic enzymes into the pancreatic causing a leakage of pancreatic enzymes into the pancreatic tissuetissue

These enzymes cause autodigestion of pancreatic These enzymes cause autodigestion of pancreatic tissue and leak into the bloodstream to cause injury to tissue and leak into the bloodstream to cause injury to blood vessels and other organsblood vessels and other organs


Disorders of the PancreasDisorders of the Pancreas PancreatitisPancreatitis

Manifestations and evaluationManifestations and evaluation• Epigastric pain radiating to the backEpigastric pain radiating to the back• Fever and leukocytosisFever and leukocytosis• Hypotension and hypovolemiaHypotension and hypovolemia

Enzymes increase vascular permeabilityEnzymes increase vascular permeability• Characterized by an increase in a patientCharacterized by an increase in a patient’’s serum s serum

amylase levelamylase level Chronic pancreatitisChronic pancreatitis

• Related to chronic alcohol abuseRelated to chronic alcohol abuse


Cancer of the Gastrointestinal Cancer of the Gastrointestinal Tract NOT ON TESTTract NOT ON TEST

EsophagusEsophagus StomachStomach Colon and rectumColon and rectum LiverLiver GallbladderGallbladder PancreasPancreas


Good to KnowGood to Know Hormones and actions in small intestineHormones and actions in small intestine Pathophysiology of the following diseasesPathophysiology of the following diseases

Ulcers, inflammatory diseases, obstructive Ulcers, inflammatory diseases, obstructive diseasesdiseases

Body system with correct diagnostic test to Body system with correct diagnostic test to determine normal/abnormal funtiondetermine normal/abnormal funtion Liver, GB, pancreas, GI structures, GI functionLiver, GB, pancreas, GI structures, GI function

patho ch 38 39 digestive system

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