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Flashcards in Esophageal Pathophysiology Deck (41)
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0
Q

Three muscles in the upper esophageal sphincter?

A

Inferior pharyngeal constrictor
Cricopharyngeus
Cervical esophagus
(all striated muscle)

1
Q

Two types of muscle in the esophagus?

A

Striated (skeletal) muscle at the top, smooth muscle for most of it.

2
Q

How is breathing related to lower esophageal sphincter (LES) function? In what condition will this not well?

A

In inhaling, contraction of diaphragm will squeeze the LES at the esophageal hiatus.
This won’t work well when patient has a hiatal hernia.

3
Q

Does the esophagus have a serosal layer? Why is that significant?

A

No. Not having a serosal layer means… cancer spreads more easily to lymphatics.

4
Q

2 nuclei in brain from which motor signals for swallowing originate?

A

Skeletal muscle: Nucleus ambiguus.

Smooth muscle: Dorsal motor nucleus (of CN X)

5
Q

Important: The dorsal motor nucleus (DMN) sends two different types of signals to smooth muscle when swallowing. Where do they come from, what are they, where do they go, and when?

A

Caudal DMN first sends inhibitory signals to smooth muscle.
Raustral DMN then sends activating signals to smooth muscle.
This happens in waves -> peristalsis.

6
Q

What kinds of synapses (i.e. which neurotransmitter) are used for inhibitory and excitatory signaling to esophagus smooth muscle?

A

Excitatory: Cholinergic
Inhibitor: Non-cholinergic (the picture says NO)

7
Q

What’s the LES doing most of the time? What happens when you swallow?

A

Having basal tone.

When there’s swallowing, relaxation is induced by NANC inhibitory neurons (using NO).

8
Q

What happens when you burp, or otherwise when the stomach is distended and stuff needs to get out?

A

Transient LES Relaxation (TLESR).

9
Q

What’s dysphagia?

A

Sensation of swallowing being abnormal.

10
Q

What’s odynophagia?

A

Pain when swallowing.

11
Q

What’s globus?

A

Sensation of something being stuck in throat.

12
Q

What is regurgitation?

A

Effortless return of material into the esophagus (not to be confused with vomiting, which is forceful)

13
Q

When a patient says “I have heartburn,” you should ask…

A

“What do you mean by heartburn?”

14
Q

What is achalasia?

A

Impaired esophageal motility.

15
Q

What parts (UES, esophagus, LES) don’t work in achalasia?

A

UES relaxes, but the peristalsis of the esophagus doesn’t happen.

16
Q

What’s the pathophysiology of achalasia?

A

Loss of myenteric inhibitory, NO-ergic neurons in the esophagus. - demonstrating the importance of the relaxation phase of peristalsis.
May be a autoimmune, viral, or neurodegenerative process.
(why they disappear just in the esophagus, we have no idea)

17
Q

Achalasia histology?

A

Inflammation in the myenteric plexus of the esophagus followed by scarring.

18
Q

What’s pseudoachalasia? Causes?

A

Mimicking of achalasia due to various cancers, surgery, benign tumors, etc.

19
Q

Treatments for achalasia?

A

Meds - not very effective
Botox injection - effect is very transient.
Pneumatic dilation
Heller myotomy (cut the LES)

20
Q

What’s the Montreal definition of GERD?

A

> 2 episodes of heartburn a week.

Adversely affecting patient’s well-being.

21
Q

Why is decreased salivation related to GERD?

A

Saliva has antacid in it.

22
Q

3 things that can cause GERD? (there are probably more)

A

Hiatal hernia - very common.
Reduced LES tone.
Delayed gastric emptying.

23
Q

In patients WITHOUT hiatal hernia, main cause of GERD is…

A

TLESR

24
Q

In patients WITH hiatal hernia, main cause of GERD…

A

is still TLESR, but other causes like strain and low LES pressure are almost as common

25
Q

What is one discreet GERD-related phenomenon that obesity increases?

A

TLESR

due to increased intra-abdominal pressure

26
Q

What does esophagus look like normally? Can it look normal in GERD?

A

“Pearly white”

Yes, patients with GERD can a normal looking esophagus.

27
Q

2 types of anti-secretory meds?

A

Proton-pump inhibitors (PPIs)

H2 antagonists

28
Q

Important lifestyle changes to help GERD?

A

Weight loss.

Avoid nighttime meals.

29
Q

Odynophagia with a irregular looking esophagus on barium swallow x-ray is bad.

A

Yeah, it might be cancer, which has a tendency to quickly metastasize.

30
Q

What is Barrett’s esophagus? What is required for diagnosis?

A

Squamous -> columnar metaplasia of the esophagus.

Diagnosis requires that you see this both in endoscopy and histology.

31
Q

Why do we care about Barrett’s esophagus?

A

It’s a precursor lesion to adenocarcinoma of the esophagus.

32
Q

Really fine detail?: 2 morphogenetic factors that might be involved in the squamous -> columnar metaplasia of Barrett’s esophagus?

A

CD-X and BMP-4

it’s tiny on the slide, but he did read it…

33
Q

3 candidate cells of origin in Barrett’s esophagus?

A

Squamous epithelium via transdifferentiation.
Stem cells (Basal layer, submucosal, hematopoetic?)
Residual embryonic tissue at GE junction

34
Q

Treatments for cancerous lesions of the esophagus?

A
Endoscopic resection (just cut it out. Curative if local.)
Radiofrequency ablation (burn away all the stuff, cut out remaining lesions later)
35
Q

What does eosinophilic esophagitis classically look like on endoscopy?

A

“trachea-like” fibrous rings
eosinophilic exudate (but it looks like pus, grossly)
food stuck in esophagus

36
Q

Common presenting symptoms of eosinophilic esophagitis?

A
Dysphagia
Food impaction
Heartburn
Chest pain
(abdominal pain and odynophagia)
37
Q

Pathophysiology of eosinophilic esophagitis?

A

Seems to be Type 2 Helper T cell (Th2)-mediated and happens in atopic (allergy-prone) patients.
Lots of cytokines: IL-13, IL-4, IL-5

38
Q

What’s the chemokine that attracts eosinophils to the esophagus?

A

Eotaxin-3 (induced by IL-13 made by Th2 cells)

39
Q

Treatment for esinophilic esophagitis? (4 things)

A

Avoid common food allergens.
Dilation
PPIs
Topical steroids

40
Q

What are 2 diseases that can cause fibrosis of the esophagus?

A

Eosinophilic esophagitis

Scleroderma