A 62-year-old man is referred to a gastroenterologist because of difficulty swallowing for the past 5 months. He has difficulty swallowing both solid and liquid foods, but there is no associated pain. He denies any shortness of breath or swelling in his legs. He immigrated from South America 10 years ago. He is a non-smoker and does not drink alcohol. His physical examination is unremarkable. A barium swallow study was ordered and the result is given below. Esophageal manometry confirms the diagnosis. What is the most likely underlying cause of this patient’s condition?

Pharyngoesophageal diverticulum

Gastroesophageal reflux disease

Squamous cell carcinoma of the esophagus

A 46-year-old woman comes to the emergency department because of intermittent abdominal pain and vomiting for 2 days. The abdominal pain is colicky and diffuse. The patient's last bowel movement was 3 days ago. She has had multiple episodes of upper abdominal pain that radiates to her scapulae and vomiting over the past 3 months; her symptoms subsided after taking ibuprofen. She has coronary artery disease, type 2 diabetes mellitus, gastroesophageal reflux disease, and osteoarthritis of both knees. Current medications include aspirin, atorvastatin, rabeprazole, insulin, and ibuprofen. She appears uncomfortable. Her temperature is 39°C (102.2°F), pulse is 111/min, and blood pressure is 108/68 mm Hg. Examination shows dry mucous membranes. The abdomen is distended and tympanitic with diffuse tenderness; bowel sounds are high-pitched. Rectal examination shows a collapsed rectum. Her hemoglobin concentration is 13.8 g/dL, leukocyte count is 14,400/mm3, and platelet count is 312,000/mm3. An x-ray of the abdomen is shown. Which of the following is the most likely cause of this patient's findings?

Colonic diverticular inflammation

A 37-year-old man presents to the physician because of dysphagia and regurgitation for the past 5 years. In recent weeks, it has become very difficult for him to ingest solid or liquid food. He has lost 3 kg (6 lb) during this time. He was admitted to the hospital last year because of pneumonia. Three years ago, he had an endoscopic procedure which partially improved his dysphagia. He takes amlodipine and nitroglycerine before meals. His vital signs are within normal limits. BMI is 19 kg/m2. Physical examination shows no abnormalities. A barium swallow X-ray is shown. Which of the following patterns of esophageal involvement is the most likely cause of this patient’s condition?

Absent peristalsis and impaired lower esophageal sphincter relaxation

Abnormal esophageal contraction with normal lower esophageal sphincter relaxation

Severely weak peristalsis and patulous lower esophageal sphincter

Poor pharyngeal propulsion and upper esophageal sphincter obstruction

Sequenced inhibition followed by contraction of the musculature along the esophagus

A 47-year-old man presents with recurrent epigastric pain and diarrhea. He has had these symptoms for the last year or so and has been to the clinic several times with similar complaints. His current dosage of omeprazole has been steadily increasing to combat his symptoms. The pain seems to be related to food intake. He describes his diarrhea as watery and unrelated to his meals. Blood pressure is 115/80 mm Hg, pulse is 76/min, and respiratory rate is 19/min. He denies tobacco or alcohol use. An upper endoscopy is performed due to his unexplained and recurrent dyspepsia and reveals thickened gastric folds with three ulcers in the first part of the duodenum, all of which are negative for H. pylori. Which of the following is the best next step in this patient's management?

Somatostatin receptor scintigraphy

A 45-year-old woman comes to the physician because of progressive difficulty swallowing solids and liquids over the past 4 months. She has lost 4 kg (9 lb) during this period. There is no history of serious illness. She emigrated to the US from Panama 7 years ago. She does not smoke cigarettes or drink alcohol. Cardiopulmonary examination shows a systolic murmur and an S3 gallop. A barium radiograph of the chest is shown. Histopathologic examination of the esophageal wall is most likely to show which of the following?

Absence of myenteric plexus neurons

Presence of intranuclear basophilic inclusions

Atrophy of esophageal smooth muscle cells

Infiltration of eosinophils in the epithelium

Presence of metaplastic columnar epithelium

A 28-year-old male presents to his primary care physician with complaints of intermittent abdominal pain and alternating bouts of constipation and diarrhea. His medical chart is not significant for any past medical problems or prior surgeries. He is not prescribed any current medications. Which of the following questions would be the most useful next question in eliciting further history from this patient?

"Can you tell me more about the symptoms you have been experiencing?"

"Does the diarrhea typically precede the constipation, or vice-versa?"

"Is the diarrhea foul-smelling?"

"Please rate your abdominal pain on a scale of 1-10, with 10 being the worst pain of your life"

"Are the symptoms worse in the morning or at night?"

GI motility disorders for USMLE Step 2 CK: High-Yield Internal Medicine Lessons

Esophageal Dysmotility - Unruly Swallowing

Achalasia: Failure of LES to relax + loss of peristalsis.
- Cause: Degeneration of inhibitory neurons in Auerbach's plexus.
- Barium swallow shows a "bird-beak" appearance.
- Manometry is diagnostic: ↑ LES pressure, incomplete relaxation.
Diffuse Esophageal Spasm (DES): Uncoordinated, strong contractions.
- Presents with intermittent chest pain and dysphagia.
- Barium swallow reveals a "corkscrew" or "rosary bead" esophagus.
- Manometry: High-amplitude, simultaneous contractions.

⭐ Exam Favorite: Chagas disease, caused by Trypanosoma cruzi, can destroy the myenteric plexus, leading to secondary achalasia.

Gastroparesis - The Stomach on Strike

Delayed gastric emptying without mechanical obstruction. Often linked to poor glycemic control in diabetics.

Etiology: Idiopathic (~50%), Diabetes Mellitus (autonomic neuropathy), post-surgical (vagal injury), medications (opioids, anticholinergics).
Clinical Features: Nausea, vomiting of undigested food, early satiety, bloating, abdominal pain.
Diagnosis: First, rule out mechanical obstruction with EGD. Gold standard is a gastric emptying study (scintigraphy) showing >10% retention at 4 hours.
Management:
- Dietary modification: Small, frequent, low-fat, low-fiber meals.
- Prokinetics: Metoclopramide, Erythromycin.

⭐ Erythromycin acts on motilin receptors to promote gastric emptying, but its effectiveness can decrease over time due to tachyphylaxis.

Gastric Emptying Scintigraphy in Gastroparesis

Ileus & Pseudo-obstruction - Deceptive Standstills

Paralytic Ileus: Functional, non-mechanical bowel hypomotility.
- Causes: Post-op (common), hypokalemia, sepsis, opiates.
- Clinical: N/V, absent bowel sounds, no flatus/stool.
- AXR: Uniformly dilated loops of both small & large bowel.
Ogilvie's Syndrome (ACPO): Acute colonic pseudo-obstruction. Massive dilation without a physical blockage.
- Risk: Elderly, sick patients (trauma, infection).
- AXR: Cecal diameter >10-12 cm indicates high perforation risk.

⭐ Ogilvie's Syndrome: If conservative management fails, administer IV neostigmine. Must exclude mechanical obstruction first to prevent perforation.

Ogilvie's syndrome: X-ray and CT findings

Irritable Bowel Syndrome - The Sensitive Gut

Chronic functional GI disorder characterized by abdominal pain and altered bowel habits. Core pathophysiology involves visceral hypersensitivity and gut-brain axis dysregulation.
Diagnosis of Exclusion: Based on Rome IV criteria-recurrent abdominal pain (≥1 day/week in last 3 months) with ≥2 of:
- Related to defecation
- Change in stool frequency
- Change in stool form (Bristol Stool Scale)
Subtypes: Predominant constipation (IBS-C), diarrhea (IBS-D), or mixed (IBS-M).
Management: Lifestyle/dietary changes (low FODMAP), fiber, antispasmodics, and targeted therapy for constipation or diarrhea.

⭐ Alarm features warranting further investigation include rectal bleeding, nocturnal diarrhea, unintentional weight loss, anemia, and age of onset >50 years.

High-Yield Points - ⚡ Biggest Takeaways

Achalasia presents with dysphagia to solids and liquids and a "bird's beak" on barium swallow, resulting from the loss of the myenteric plexus.

GERD is most often caused by transient LES relaxation; its main complication is Barrett's esophagus, a precursor to adenocarcinoma.

Diabetic gastroparesis is a state of delayed gastric emptying without obstruction; treat with metoclopramide.

Hirschsprung disease is a congenital aganglionosis of the colon; diagnose with rectal biopsy.

Diffuse esophageal spasm appears as a "corkscrew" esophagus on imaging.

Continue reading on Oncourse

CONTINUE READING — FREE

or get the app

App Store|Google Play