GASTROINTESTINAL, LIVER, BILIARY TRACT AND PANCREAS PATHOLOGY Flashcards
Most common craniofacial malformation in the newborn?
Cleft lip/palate
Why does a cleft lip/palate occur
Failure of fusion of fetal nasal and maxillary processes
Cleft lip/palate etiology
Genetic factors and some evidence for environmental (maternal medications, smoking, etc.)
How many cleft lip/palate cases are linked to genetic syndromes (example)
30% (The best known syndrome with cleft lip/palate is 22q11 deletion syndrome (DiGeorge syndrome))
Dental Carries (Tooth Cavities)
Erosion of the hard outer layer of the tooth (the enamel) by acids produced by bacteria
Risk factors for dental carries (tooth cavities)
- Poor oral hygiene
- Structural abnormalities (promoting plaque formation)
- Sugary foods
- Lack of saliva (to buffer bacterial acid)
- Genetics?
Pulpitis
The cavity in the tooth enamel erodes through the dentin layer and into the the tooth pulp. This is when dental (painful) (bacteria can infect)
Gingivitis
Inflammation of the gums caused by bacterial plaques on and around the teeth (inflammation of the gums)
Periodontitis
Severe gingivitis where the gum retracts from the teeth
Effects of periodontitis
- Teeth loosening or falling out
- Bad breath
- Infection spread to rest of jaw
- Potential sepsis
Sepsis
Bacterial infection of the blood (can be life-threatening)
Potential effects from severe dental infections (e.x. pulpitis, periodontitis) where bacteria move into the blood
- Sepsis
- Bacteria can lodge (E.x. lodge on heart valves forming biofilms > infectious endocarditis)
Stomatitis
Inflamed/sore mouth
Recurrent aphthous stomatitis (‘canker sores’)
What is it? Cause?
- Discrete, painful mouth ulcers that usually spontaneously resolve within 2 weeks
- Unknown cause
Infectious stomatitis
Pocket of fluid bound by squamous mucosa
Infectious stomatitis (Herpes virus - ‘Cold sores’)
Typically starts as a vesicle initially, and may later ulcerate
Infectious stomatitis (Candida fungus - ‘oral thrush’)
Who does this effect?
Can affect infants, the immunosuppressed and users of inhaled corticosteroids
Oral cavity neoplasm
What cell type do they affect
- Vast majority are squamous
Leukoplakia
Persistent white patch mouth lesion
Erythroplakia
Persistent red patch mouth lesion
Causes for mouth lesions
Heavy consumption of alcohol and with tobacco use (cause concern for squamous cell carcinoma)
Squamous cell carcinoma
Occurs when the oral squamous epithelium acquires genetic mutations, mainly from toxins, human papillomavirus (HPV) or
radiation
2 main types of squamous cell carcinoma
What types? Where do they tend to occur?
1) Associated with alcohol and tobacco use (tongue)
2) Associated with associated with HPV infection (oropharynx (tonsils location))
3) Other (radiation, UV, immunosupression)
squamous cell carcinoma progression
Dysplasia (increasing grade) > squamous cell carcinoma in situ > invasive squamous cell carcinoma > metastasis to neck regional lymph nodes and/or distant metastases
Sialadenitis
Inflammation of salivary glands (can lead to gingivitis)
Sialadenitis causes
2 types of causes and examples
Infectious causes:
- Bacterial ( S. aureus ), viral (mumps)
Non-infectious causes:
- Sjögren syndrome (autoimmune): inflammation of salivary and lacrimal glands
- Sialolithasis (stones in salivary gland)
- Therapeutic radiation
Salivary gland neoplasms
- Benign (commonly pleomorphic adenoma)
- Malignant (commonly mucoepidermoid carcinoma)
Hiatus hernia
What is it? cause?
- Displacement of portion of the stomach above the diaphragm
- Cause unkown (genetics?)
Types of hiatus hernias
Types; definition; prevalence
Sliding hernia:
- 95% prevalence
- Sliding of gastroesophageal junction and cardia of stomach upwards
Paraesophageal hernia:
- 5% prevalence
- Portion of stomach protruding upward and
forming pocket beside esophagus (caused by prior surgery)
Achalasia
What is it? Effects?
Degeneration of the ganglion cells in the
myenteric plexus (distal esophagus)
Achalasia effects
Prevents the lower esophageal sphincter
from relaxing and decreases peristalsis in
the distal esophagus (dysphagia)
Achalasia causes
- Primary cause unknown
- Can occur secondary to parasitic infection
Varices
Dilation of submucosal veins of the distal esophagus
Varcies effects
The dilated veins can rupture, which can lead to life threatening bleeding
Varcies causes and treatment
Cause: Hepatic cirrhosis (causes hypertension in the portal vein system is the commonest cause)
Treatment: Endoscopically or with medications
Esophagitis
Inflammation of the esophagus (mainly of the squamous lining)
Gastroesophageal Reflux Disease (GERD)
Reflux of gastric contents into esophagus that causes a chemical esophagitis
Increased pressure in the stomach + insufficient lower esophageal sphincter tone
Gastroesophageal Reflux Disease (GERD) causes
Very numerous causes and risk factors are known, common ones include: smoking, alcohol abuse, obesity, pregnancy, excessive caffeine use
Esophagitis causes
- GERD
- Infectious causes: viral (herpes simplex virus), fungal (Candida)
- Ingestion of irritating substances (some pills/medications, bleach, others)
- Inflammatory conditions/allergy (eosinophilic esophagitis)
- Various autoimmune diseases
Barrett Esophagus
- A complication of GERD (exacerbated by excessive alcohol and/or tobacco use)
- Due to chronic irritation
- The intestinal metaplasia has a risk of progression to dysplasia and then to esophageal adenocarcinoma
-Some patients with Barrett esophagus require biopsy screening for early detection and treatment of dysplasia/adenocarcinoma
Most common esophageal carcinomas
Types; location; risk factors
Squamous cell carcinoma
- Upper-mid esophagus
- Risk factors: alcohol and tobacco
Adenocarcinoma
- Distal esophagus
- Risk factors: GERD and Barrett esophagus; obesity and smoking also
Signs/symptoms of esophageal carcinoma:
- Occult gastrointestinal bleeding (anemia)
- Unintentional weight loss
- Progressive difficulty swallowing (dysphagia)
- Pain on swallowing (odynophagia)
Gastritis
Inflammation of the mucosal lining of the stomach (acute or chronic)
Acute gastritis
Type of lymphocytes; causes
- Neutrophils present
- Causes: Drugs (aspirin), alcohol, severe
physiologic stress (burns, trauma, etc.)
Chronic gastritis
Lymphocytes; causes
- Increased lymphocytes and plasma cells
- Causes: Helicobacter pylori infection and autoimmune gastritis (two most common); also autoimmune/inflammatory conditions
Gastropathy
Injury to the stomach lining in the setting of little or no inflammation
- Erosion or ulceration
- Causes: chemical; vascular injuries; physiological stress
Peptic ulcer disease
Ulceration of gastric or duodenal mucosa in the
setting of acute or chronic gastritis
Causes: H. pylori, reduced mucosal barrier, drugs, others
Peptic ulcer disease complications
- Hemorrhage > melena, iron deficiency anemia, hematemesis
- Perforation > peritonitis
- Penetration > ulcer penetrates into pancreas
- Scarring > stenosis > obstruction
Helicobacter Gastritis
What is it (cause)? Risk factors?
Caused by infection by Helicobacter pylori (fecal oral transmitted; bacterium hides in the gastric mucus)
Risk factors:
- Longstanding infection risk factor for malignancy
Parietal cells
Produce HCl and intrinsic factor
Chief cells
Produce pepsinogen
G cells
Produce gastrin
Autoimmune Gastritis
Immune system recognizes parietal cells as foreign and destroys them
Autoimmune Gastritis effects
- Stomach and fundus chronically inflamed
and atrophic - Parietal cells destroyed (and chief cells as bystanders)
- G cells produce lots more gastrin
Autoimmune Gastritis consequences
1) Inability to Absorb B12
2) Increased Risk of Gastric Adenocarcinoma
3) Increased Risk of Gastric Well Differentiated Neuroendocrine Tumor
Autoimmune Gastritis consequence: Inability to Absorb B12
- No intrinsic factor > the body cannot absorb vitamin B12 > megaloblastic anemia
- Chronic lack of vitamin B12 can also lead to
irreversible nerve damage
Treatment:
* Diagnosis of autoimmune gastritis
* Supplementation with vitamin B12
Autoimmune Gastritis consequence: Increased Risk of Gastric Adenocarcinoma
- Chronic inflammation, atrophy
and intestinal metaplasia in the fundus/body
increases risk of gastric adenocarcinoma - High levels of gastrin are produced by G cells because of the lack of stomach acid being produced
- Elevated gastrin > carcinogenesis
- Solution: Biopsy screening for intestinal
metaplasia and early gastric adenocarcinoma
Autoimmune Gastritis consequence: Increased Risk of Well-Differentiated Neuroendocrine Tumor
High production of gastrin → proliferation of stomach endocrine cells → neuroendocrine tumor
Solution: Good prognosis (low risk of spread) → removal
Gastric adenocarcinoma risk factors
- H. pylori gastritis
- Autoimmune gastritis
- Nitrosamine exposure
Gastric adenocarcinoma histological classification
Intestinal type: forms polypoid mass or tumor
Diffuse type: Spreads over wall
Mixed type: Bit of both
Gastric adenocarcinoma metastasis
- Lymph node
- Bilateral ovarian spread
Gastric lymphoma most common type
MALT lymphoma
MALT lymphoma
Progression? Cause?
Progression: Slow (low grade) but can transform into high grade
Cause: H. pylori infection
Meckel’s Diverticulum
Developmental disorder of small intestine where a portion of the vitelline duct remains open (rule of 2: population affected; developing symtopms; etc.)
Celiac disease
Gluten allergy (products of gluten breakdown trigger allergic response)
- Malabsorption results from damage to small intestine mucosa (excess lymphocytes in epithelium; atrophy of villi; inflammation)
Inflammatory Bowel Disease
2 diseases characterized by recurrent inflammation of the intestines: Crohn’s and Ulcerative Collitis
IBD etiology
Uknown
Crohn’s and UC similarities
- Common in caucasians
- Familial predisposition
- Extra-intestinal manifestations (arthritis, skin lesions, liver)
- Predispose to dysplasia and carcinoma
Crohn’s Disease
Inflammation involving all layers of the bowel wall (causes deep ulcers, strictures, fistulas, and adhesions)
Crohn’s Disease
Location; inflammation pattern; granulomas
Location: Often right colon and small intestine (anus involved; rectum spared)
Inflammation pattern: Patchy and discontinuous
Granulomas: Many cases have granulomas in the bowel wall
Ulcerative Colitis
Inflammation involving only the mucus (shallow ulcers) → may stop peristalsis if severe
Ulcerative Colitis
Location; Inflammation pattern; granulomas
Location: Starts in the rectum and proceeds proximally (rectum and left colon)
Inflammation pattern: continuous
Granulomas: No
Diverticular disease
Outpouching of the bowel that forms a blind ended segment
True diverticula: Meckel diverticulum (all layers of the bowl wall)
False diverticula: Acquired (only mucus)
Diverticulus disease complications
Diverticulosis = Many diverticula
- Wall of the diverticula is quite thin → bleeding
Diverticulitis = Inflammation of diverticula
- Pouches become obstructed with stool → bacteria trapped → inflammation
Colorectal adenocarcinoma
Commoness? Risk factors? Cause? Metastasis method? Assessment?
Commoness: Top 3 most common malignancy and cause of death for men and women
Risk factors: General (age, obesity, smoking, etc.)
Cause: tend to be IBD-associated; genetic syndromes)
Metastasis method: via lymphatics or blood
Assessment: Colonoscopy screening (neoplastic colon polyps)
Jaundice/Hyperbilirubinemia
A symptom (not disease) describing yellow discolouration of the skin, eyes and mucosa
Jaundice classification
- Pre-hepatic (E.x. hemolysis of RBC releases bilirubin)
- Hepatic (E.x. liver damaged → bilirubin build up)
- Post-hepatic (E.x. bile cannot be excreted)
Bilirubin
Function; “life cycle”
Bilirubin helps digest fats
Hemoglobin breakdown → heme and globulin → heme loses iron → bilirubin → binds to albumin → conjugated in the liver →excreted into bile
Hemochromatosis
Autosomal recessive disorder of iron metabolism preventing the liver from regulating iron
Hemochromatosis effects
Iron builds up and leaves scaring, liver failure, increased carcinoma risk
Hepatitis A
Transmission; effects; symptoms; vaccine
Transmission: Fecal-oral
Effects: Acute infection (if severe → liver failure)
Symptoms: asymptomatic or mild
Vaccine: Preventative
Hepatitis B
Virus type; transmission; effects; symptoms; vaccine
Virus type: DNA
Transmission: Fluid
Effects: chance of chronic infection; scarring and cirrhosis; carcinoma
Symptoms: 2/3 asymptomatic
Vaccine: Preventative
Hepatitis C
Virus type; transmission; effects; symptoms; vaccine
Virus type: RNA
Transmission: Fluid
Effects: likely chronic infection; cirrhosis; major risk factor of carcinoma
Vaccine: None
Hepatitis E
Virus type; transmission; effects
Similar to A
Virus type: RNA
Transmission: Fecal-oral
Effects: Acute
Hepatitis D
Requires co-infection with hepatitis B (similar transmission and symptoms; greater liklihood of liver failure)
Cirrhosis
- Common end stage of many liver diseases (chronic liver disease causing scarring)
- Liver is not able to regenerate and perform normal functions (Resulting in: portal hypertension, jaundice, bleeding, etc.)
Clinical features of cirrhosis
JAG H BEEP:
- Jaundice (cannot metabolize bilirubin → yellow coloration)
- Ascites (low serum albumin and portal hypertension → fluid in peritoneal cavity)
- Gynecomastia (cannot detoxify estrogen → male breasts)
- Hematemesis (esophageal bleeding → vomiting/passing blood)
- Bleeding (No clotting factors →easily bruise)
- Edema (low plasma oncotic pressure (no albumin) → swelling)
- Encephalopathy (cannot remove toxins → unconsioucness)
- Pleural effusion (low albumin → fluid in pleural cavity)
Gallstones (cholelithiasis)
Stones in gall bladder
Types of gallbladder stones
- Cholesterol stones (most common)
- Pigment stones
- Mixed stones
Cholesterol stones
What are they? Risk factors?
Excess cholesterol secretion by the liver
Risk factors (4 F’s): Female, Over Forty, Fertile, Fat
Cholelithiasis complications
- Cholecystitis
- Stones obstruct bile duct (jaundice; ascending cholangitis)
- Obstruction of bowel
- Risk factor for gall bladder cancer
Chronic Pancreatitis
What is it? Causes? Effects?
Persistence of inflammation (after original inciting agent removed)
Potential causes: Cystic fibrosis, alcohol
Effects: fibrosis, exocrine/endocrine insufficiency
Pancreatic ductal adenocarcinoma (PDAC)
Diagnosis?
Very difficult to detect early (usually asymptomatic) eventually presents with jaundice because of obstruction of the common bile duct
At diagnosis: Often already metastatic; poor prognosis
Pancreatic well differentiated neuroendocrine tumors (WDNETs)
Malignant tumors arising from endocrine cells of pancreatic islets
Diagnosis: Better prognosis than PDAC, but can metastasize and kill
