,USMLE Step 3 – Gastroenterology High-
Yield Notes | Complete Review for Exam
Prep 2025/2026.
Dysphagia
Difficulty swallowing
Odynophagia
Painful swallowing
- infectious process -- HIV, HSV, Candida, CMV
Clinical presentation for Achalasia
-young nonsmoker
-dysphagia with solids & liquids
-regurgitation of food particles
-possible aspiration of previously eaten material
-progressively worsens
Diagnostic tests for Achalasia
Best initial: Barium swallow
Most accurate: Esophageal manometry
--absense of normal esophageal peristalsis
--high pressure at lower esophageal sphincter (LES)
Treatment for Achalasia
Best initial: surgical myotomy, or pneumatic dilation if surgery is unsuccessful
If pt refuses surgery or pneumatic dilation then Botulinum toxin injection
Mechanism for botulinum toxin
Inhibits release of acetylcholine at NMJ -- inhibiting nicotinic receptors, relaxing all skeletal muscle
Clinical presentation for Esophageal Cancer
-pt >50 yo, usually smoker and/or drinker
-dysphagia with solids, then liquids later
-heme positive stool or anemia
-weight loss
Diagnostic tests for Esophageal Cancer
,Best initial: endoscopy
Barium swallow if endoscopy is not available
NOT Manometry
Most accurate: biopsy
Treatment for esophageal cancer
Best initial: surgical resection
Chemotherapy based on 5-fluorouracil
Etiology of peptic strictures (rings & webs)
-repetive exposure of esophagus to acid
-previous use of sclerosing agents for variceal bleeding
Diagnostic testing for peptic strictures
barium study
Differential for peptic strictures
-Plummer-Vinson syndrome
-Schatzki ring (peptic stricture)
-Peptic stricture
Definition and treatment for Plummer-Vinson syndrome
-proximal stricture in context of iron deficiency anema
-more common in middle aged women
-assoc with squamous cell esophageal cancer
**Best initial therapy -- Iron replacement
Definition and treatment for Schatzki ring.
-distal ring of esophagus; presents with intermittent symptoms of dysphagia
**Best initial therapy -- penumatic dilation
Definition and treatment for peptic stricture
-Results from acid refulx
-Treat with pneumatic dilation
Clinical presentation of zenker diverticulum
-patient with dysphagia and horrible breath (2/2 food rotting at back of esophagus 2/2 dilation for the
posterior pharyngeal constrictor muscles
Diagnostic test(s) and therapies for Zenker diverticum
Best inital test -- barium study
Best initial therapy -- surgical resection
***avoid perforation. DO NOT put an endoscope or NGT in Zenker
, Clinical presentation of Diffuse Esophageal Spasms (nutcraker esophagus)?
-severe chest pain without RFs for ischemic hear disease
-pain occurring after drinking a cold beverage
Diagnotic testing for diffuse esophageal spasms
Most accurate: Manometry which will show periodic high amplitude, nonperistaltic waves
-Barium studies may show corksew pattern (only if in episode is in process
Treatment for diffuse esophageal spasm
Calcium Channel Blockers and nitrates
What cardiac issue is a esophageal spasm similar to?
-Prinzmetal variant angina (treatment is same)
Clinical presentation of Scleroderma (progressive systermic sclerosis)
-Usually symptoms of reflux
Diagnostic test for scleroderma
-Manometry showing absence of peristaltic waves in lower 2/3 of esophagus and significant decrease in
LES tone
Treatment for scleroderma
Proton pump inhibitors
Esophageal candidiasis presentation
odynophagia in an HIV + pt with CD4 count <100
Diagnosis and treatment of esophageal candidiasis
empiric fluconazole
Clinical presentation of esophagitis
pain with swallowing as food rubs against the esophagus
Differential for esophagitis
-Esophageal Candidiasis in HIV positive patients
-Pill induced: doxycycline, bisphosphonates (alendronate)
Diagnostic testing and treatment of Esophagitis
-If HIV negative -- endoscopy
-If HIV positive w/ <100 CD4 cells give fluconazole
Treatment of pill induced esophagitis?
Yield Notes | Complete Review for Exam
Prep 2025/2026.
Dysphagia
Difficulty swallowing
Odynophagia
Painful swallowing
- infectious process -- HIV, HSV, Candida, CMV
Clinical presentation for Achalasia
-young nonsmoker
-dysphagia with solids & liquids
-regurgitation of food particles
-possible aspiration of previously eaten material
-progressively worsens
Diagnostic tests for Achalasia
Best initial: Barium swallow
Most accurate: Esophageal manometry
--absense of normal esophageal peristalsis
--high pressure at lower esophageal sphincter (LES)
Treatment for Achalasia
Best initial: surgical myotomy, or pneumatic dilation if surgery is unsuccessful
If pt refuses surgery or pneumatic dilation then Botulinum toxin injection
Mechanism for botulinum toxin
Inhibits release of acetylcholine at NMJ -- inhibiting nicotinic receptors, relaxing all skeletal muscle
Clinical presentation for Esophageal Cancer
-pt >50 yo, usually smoker and/or drinker
-dysphagia with solids, then liquids later
-heme positive stool or anemia
-weight loss
Diagnostic tests for Esophageal Cancer
,Best initial: endoscopy
Barium swallow if endoscopy is not available
NOT Manometry
Most accurate: biopsy
Treatment for esophageal cancer
Best initial: surgical resection
Chemotherapy based on 5-fluorouracil
Etiology of peptic strictures (rings & webs)
-repetive exposure of esophagus to acid
-previous use of sclerosing agents for variceal bleeding
Diagnostic testing for peptic strictures
barium study
Differential for peptic strictures
-Plummer-Vinson syndrome
-Schatzki ring (peptic stricture)
-Peptic stricture
Definition and treatment for Plummer-Vinson syndrome
-proximal stricture in context of iron deficiency anema
-more common in middle aged women
-assoc with squamous cell esophageal cancer
**Best initial therapy -- Iron replacement
Definition and treatment for Schatzki ring.
-distal ring of esophagus; presents with intermittent symptoms of dysphagia
**Best initial therapy -- penumatic dilation
Definition and treatment for peptic stricture
-Results from acid refulx
-Treat with pneumatic dilation
Clinical presentation of zenker diverticulum
-patient with dysphagia and horrible breath (2/2 food rotting at back of esophagus 2/2 dilation for the
posterior pharyngeal constrictor muscles
Diagnostic test(s) and therapies for Zenker diverticum
Best inital test -- barium study
Best initial therapy -- surgical resection
***avoid perforation. DO NOT put an endoscope or NGT in Zenker
, Clinical presentation of Diffuse Esophageal Spasms (nutcraker esophagus)?
-severe chest pain without RFs for ischemic hear disease
-pain occurring after drinking a cold beverage
Diagnotic testing for diffuse esophageal spasms
Most accurate: Manometry which will show periodic high amplitude, nonperistaltic waves
-Barium studies may show corksew pattern (only if in episode is in process
Treatment for diffuse esophageal spasm
Calcium Channel Blockers and nitrates
What cardiac issue is a esophageal spasm similar to?
-Prinzmetal variant angina (treatment is same)
Clinical presentation of Scleroderma (progressive systermic sclerosis)
-Usually symptoms of reflux
Diagnostic test for scleroderma
-Manometry showing absence of peristaltic waves in lower 2/3 of esophagus and significant decrease in
LES tone
Treatment for scleroderma
Proton pump inhibitors
Esophageal candidiasis presentation
odynophagia in an HIV + pt with CD4 count <100
Diagnosis and treatment of esophageal candidiasis
empiric fluconazole
Clinical presentation of esophagitis
pain with swallowing as food rubs against the esophagus
Differential for esophagitis
-Esophageal Candidiasis in HIV positive patients
-Pill induced: doxycycline, bisphosphonates (alendronate)
Diagnostic testing and treatment of Esophagitis
-If HIV negative -- endoscopy
-If HIV positive w/ <100 CD4 cells give fluconazole
Treatment of pill induced esophagitis?
