POSTPARIATRIC HYPOS MCQ Flashcards
What is Roux-en-Y Gastric Bypass (RYGB)?
A type of bariatric surgery for BMI ≥ 40 kg/m² or ≥ 35 kg/m² with comorbidity
Complications include stomal stenosis, marginal ulcers, bowel obstruction, dumping syndrome, gallstones, hernias, malnutrition, and postbariatric hypoglycemia.
What percentage of RYGB patients experience postbariatric hypoglycemia about 1 year after surgery?
2%
Symptoms occur 1-3 hours after simple carbohydrate consumption.
What are the autonomic symptoms of postbariatric hypoglycemia?
- Tremors
- Palpitations
- Hunger
- Sweating
Neuroglycopenic symptoms include weakness, confusion, and altered consciousness.
What are some mechanisms contributing to postbariatric hypoglycemia?
- Increased levels of GLP-1 and gastric inhibitory peptide
- Increased sensitivity of β-cells to GLP-1
- Increased pancreatic islet-cell mass
- Increased insulin sensitivity after weight loss
- Inappropriate insulin secretion
- Abnormal response to hypoglycemia
The condition is multifactorial.
How do symptoms of dumping syndrome differ from postbariatric hypoglycemia?
In dumping syndrome, symptoms start within minutes to 60 minutes after calorie-dense food ingestion.
What is required for the diagnosis of postbariatric hypoglycemia?
Detailed history including:
* Symptoms during episodes
* Frequency and timing relative to meals
* Presence of nocturnal symptoms
* Dietary history
Fingerstick glucose measurements are inaccurate <70 mg/dL for diagnosis; use plasma glucose postprandially.
What is the preferred diagnostic test for postbariatric hypoglycemia?
Mixed-meal test using the patient’s triggering food.
A positive test shows normal fasting glucose, early hyperglycemia, then hypoglycemia <50 mg/dL.
What dietary modifications are crucial for managing postbariatric hypoglycemia?
Low-simple carb, high-protein, high-fiber diet.
Referral to a dietitian is recommended and resolves hypoglycemia in most cases.
What is the first-line treatment for postbariatric hypoglycemia?
Dietary changes are effective in resolving hypoglycemia episodes.
What is the preferred initial pharmacotherapy for postbariatric hypoglycemia if dietary changes are insufficient?
Acarbose (25 mg with each meal).
Other medications include Nifedipine, diazoxide, and octreotide.
What surgical options may be considered if medical therapies fail for postbariatric hypoglycemia?
- Gastrostomy tube placement
- Gastric outlet restriction
- Roux-en-Y gastric bypass reversal
What is involved in a 72-hour fast for diagnosing hypoglycemia?
Supervised monitoring for hypoglycemia symptoms, with tests including glucose, insulin, C-peptide, proinsulin, and β-hydroxybutyrate.
What are the indications for a 72-hour fast?
- Atypical symptoms
- Fasting-induced episodes
- Postprandial symptoms >4 hours after a meal
- Symptoms <1 year after surgery
Why is the Oral Glucose Tolerance Test (OGTT) not suitable for evaluating postbariatric hypoglycemia?
Due to the risk of dumping syndrome.
What is a limitation of the OGTT?
Up to 10% of healthy individuals can have glucose <50 mg/dL (<2.8 mmol/L) without symptoms during this test.
