Esophagus (Week 10)

Question 1

How long is the esophagus?

Answer 1

~ 25cm

Question 2

Where is the esophagus located?

Answer 2

posterior to trachea

begins at inferior end of laryngopharynx and ends in superior portion of stomach

Question 3

The esophagus pierces the diaphragm through the ______________

Answer 3

esophageal hiatus

Question 4

What type of cells are in the epithelium of the esophagus?

Answer 4

squamous stratified

Question 5

What is the name of the resident dendritic cells that reside in the esophagus’ epithelium?

Answer 5

Langerhans cells

Question 6

Lymphoid nodules (containing B cells and T cells) are found in the ____________ of the esophagus

Answer 6

lamina propria

Question 7

Cardiac glands, that secrete mucous to protect the esophagus, are found where?

Answer 7

lamina propria

Note: there are 2 clusters (near pharynx and stomach)

Question 8

What type of connective tissue is found in the submucosa of the esophagus?

Answer 8

dense, irregular fibroelastic connective tissue

Question 9

What are the different layers of the muscularis of the esophagus?

Answer 9

upper 1/3 = mostly skeletal muscle

middle 1/3 = mixed

lower 1/3 = mostly smooth muscle

Question 10

True or False: We see the adventitia of the esophagus until it pierces the diaphragm, after which it is serosa

Answer 10

True

Question 11

What are the major arteries that supply the esophagus?

Answer 11

• thoracic branches of the aorta (superiorly)
• branches of the left gastric artery (inferiorly)

Question 12

What are the major veins that drain the esophagus?

Answer 12

• azygous vein
• portal venous system via the left gastric veins

Question 13

The __________ compresses the esophagus superiorly to some extent

Answer 13

larynx

Question 14

What muscles are involved in “pushing food down” when swallowing?

Answer 14

• cricopharyngeus muscle
• the rest of the inferior pharyngeal constrictor muscle

Question 15

when an out-pouching develops and food gets stuck in the weak spot just above the cricopharyngeus muscle

Answer 15

Zencker Diverticulum

Note: out-pouching occurs due to cricopharyngeus muscle over-tightening

Question 16

What are the three stages of deglutition (swallowing)?

Answer 16

1) voluntary stage
2) pharyngeal stage
3) esophageal stage

Question 17

Describe the voluntary stage of deglutition (swallowing)

Answer 17

after chewing, food is voluntarily squeezed/rolled posteriorly into the pharynx by pressure of the tongue upward and backward against the palate

Question 18

Describe the pharyngeal stage of deglutition (swallowing)

Answer 18

• a reflex controlled by the brain stem (medulla), triggered by food in the pharynx (tactile stimulation)
• soft palate is pulled upwards (prevents food from getting into nose)
• palatopharyngeal folds pulled together, creating a sagittal slit for food to pass with ease

Question 19

Describe the esophageal stage of deglutition (swallowing)

Answer 19

• trachea is closed (respiration inhibited temporarily), as vocal chords are brought together and larynx is raised and epiglottis covers vocal chords
• upper esophageal sphincter relaxes
• peristaltic contraction of pharynx

Question 20

Where is the swallowing center? What does it do?

Answer 20

medulla (brain stem)

coordinates activity from vagal nuclei with other centers (e.g., inhibits respiratory center)

Question 21

Where does the swallowing center receive sensory inputs from?

Answer 21

pharynx and esophagus

Question 22

How long is the pharyngeal swallowing stage?

Answer 22

less than 2 seconds

Note: Therefore, only interrupts respiration for a very small amount of time

Question 23

_____________ results from distension of the esophagus by retained food, or by reflux of gastric contents into the esophagus; continues until all the food has emptied into the stomach

Answer 23

Secondary peristalsis

Question 24

Where is the lower esophageal sphincter located?

Answer 24

1-2 cm below diaphragm

2-5 cm above juncture with stomach

Question 25

True or False: The lower esophageal sphincter (LES) relaxes ahead of the peristaltic wave to allow easy propulsion of food into the stomach and to prevent reflux

Answer 25

True

Question 26

At rest, is the pressure high or low at the upper esophageal sphincter (UES)?

Answer 26

high

Question 27

At rest, is the pressure high or low at the lower esophageal sphincter (LES)?

Answer 27

low (so that food can pass through)

Question 28

After food has passed into the stomach, is pressure high or low in at the lower esophageal sphincter (LES)?

Answer 28

high

Question 29

What causes relaxation of the lower esophageal sphincter (LES)?

Answer 29

nitric oxide (NO) and VIP-secreting branches of the vagus nerve

Question 30

What are some types/groups of pathologies that can occur in the esophagus?

Answer 30

1) dysphagic/motility diseases 2) inflammatory diseases 3) metaplastic/neoplastic diseases (future lectures) 4) vascular diseases (future lectures)

Question 31

a motility/obstructive disorder whereby swallowing contractions are too powerful (high amplitude esophageal contractions), visceral pain from the esophagus is well-localized, and excess distension causes intense and brief chest pain

Answer 31

Nutcracker esophagus

Question 32

In Nutcracker esophagus, the ___________ layer of smooth muscle contracts before the ___________ layer

Answer 32

outer longitudinal, inner circular

Question 33

a motility disorder of the esophagus characterized by a dysfunction of inhibitory nerves resulting in minor obstruction or chest pain

Answer 33

diffuse esophageal spasm Note: this is very common

Question 34

a motility disorder of the esophagus characterized by increased tone of the lower esophageal sphincter (LES) due to impaired smooth muscle relaxation (aka LES won't relax), and aperistalsis of the esophagus

Answer 34

achalasia Note: If inhibitory neurons do not release NO or VIP after swallowing, the LES won't relax properly

Question 35

__________ (primary/secondary) achalasia may be associated with diabetic autonomic neuropathy, malignancy, and infections (e.g., from tropical countries)

Answer 35

Secondary

Question 36

____________ (primary/secondary) achalasia is idiopathic and caused by failure of distal esophageal inhibitory neurons

Answer 36

Primary

Question 37

How does achalasia present clinically?

Answer 37

- dysphagia (difficulty swallowing) - chest pain - regurgitation

Question 38

True or False: Achalasia increases mortality, especially when malignancy is involved

Answer 38

False Achalasia does NOT affect mortality, UNLESS malignancy is involved

Question 39

What is the treatment for achalasia?

Answer 39

- botox - myotomy

Question 40

Other causes of dysphagia may include iron-deficiency anemia or chronic reflex disease. How do these conditions cause dysphagia?

Answer 40

they can sometimes cause fibrosis or non-malignant growths that obstruct the esophagus

Question 41

True or False: Worsening dysphagia and reflux symptoms need to be investigated to ensure that the patient has not developed esophageal cancer

Answer 41

True

Question 42

an inflammatory condition of the esophagus that is usually a sign of immunosuppression involving HSV, cytomegalovirus (CMV) or fungal organisms (candidiasis = most common)

Answer 42

infectious esophagitis

Question 43

an inflammatory condition of the esophagus which may be due to Crohn's disease (rare), scleroderma, or eosinophilic esophagitis

Answer 43

autoimmune esophagitis

Question 44

In eosinophilic esophagitis, there are ______ eosinophils/per high-power field

Answer 44

>15

Question 45

True or False: Eosinophilic esophagitis is an emerging disease, with increasing incidence (both children and adults)

Answer 45

True

Question 46

Describe the pathophysiology of eosinophilic esophagitis

Answer 46

- Th2 response with an abundance of IL-4, IL-5, and IL-13 in the serum and in affected tissue - often a history of atopic illness (e.g., asthma, eczema) during or before GI symptoms - food intolerances/allergies = major inciting factors

Question 47

What are the clinical features of eosinophilic esophagitis in children?

Answer 47

- nausea - vomiting - small for age - weight loss (severe cases) - heartburn/reflux (in older children)

Question 48

What are the clinical features of eosinophilic esophagitis in adults?

Answer 48

- dysphagia (difficulty swallowing) - food impaction - chest pain (possible) - heartburn that is usually resistant to PPI treatment

Question 49

How is eosinophilic esophagitis diagnosed?

Answer 49

- endoscopy - IgE levels elevated

Question 50

What is the most frequent cause of esophagitis?

Answer 50

reflux esophagitis (reflux of gastric contents into the lower esophagus)

Question 51

True or False: In reflux esophagitis, the histology of the esophagus is normal (e.g., stratified squamous epithelium)

Answer 51

True Note: Stratified squamous epithelium is resistant to abrasion from food but is sensitive to acid

Question 52

True or False: Decreased LES tone or increased abdominal pressure can contribute to GERD

Answer 52

True

Question 53

What are some aggravating factors for reflux esophagitis?

Answer 53

- alcohol and tobacco use - obesity - CNS depressants - pregnancy - hiatal hernia - delayed gastric emptying - increased gastric volume

Question 54

What are some findings associated with reflux esophagitis?

Answer 54

- hyperemia (increased blood flow to esophagus) - mild eosinophilic infiltration - basal zone hyperplasia** exceeding 20% of total epithelial thickness - elongation of lamina propria papillae (severe cases) - Barrett's esophagus* in more severe cases (patches of red, velvety mucosa; can be pre-malignant in rare cases and should be followed over time via endoscopy)

Question 55

What are the clinical features of reflux esophagitis?

Answer 55

- dysphagia - heartburn - regurgitation (less frequently) - chronic GERD may be punctuated by severe chest pain attacks (rare)

Question 56

How is reflux esophagitis treated?

Answer 56

proton pump inhibitors or H2 histamine receptor antagonists

Question 57

True or False: Severity of symptoms and disease duration in reflux esophagitis is closely related to the degree of histological damage

Answer 57

False Only disease duration is closely related to degree of histological damage (severity of symptoms is not necessarily related to degree of histological damage)

Question 58

Heartburn that increases in severity and is accompanied by dysphagia is a red flag for _______________

Answer 58

esophageal carcinoma

Question 59

What are some food triggers for reflux esophagitis?

Answer 59

- coffee and tea - choclate - spicy food - beer, wine, other forms of alcohol - fried or greasy foods - mint - tomatoes or tomato-based food - sweets and high-glycemic foods Note: over-eating and stress can also trigger reflux