Hipoglucemia diagnostico diferencial. Etiologia.
🩺 Hypoglycemia
Hypoglycemia is defined as a plasma glucose level <70 mg/dL (3.9 mmol/L). Symptoms typically begin below this threshold and intensify with lower glucose levels. It can be classified as:
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Fasting hypoglycemia
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Postprandial (reactive) hypoglycemia
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Factitious or iatrogenic hypoglycemia
🔍 Etiology of Hypoglycemia
1. Drug-Induced Hypoglycemia (Most common cause)
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Insulin (exogenous overdose or timing mismatch)
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Sulfonylureas (e.g., glipizide, glyburide)
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Meglitinides (e.g., repaglinide)
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Quinine, pentamidine, β-blockers (mask symptoms), salicylates
2. Endocrine Disorders
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Adrenal insufficiency (↓ cortisol → impaired gluconeogenesis)
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Hypopituitarism (↓ GH and ACTH → hypoglycemia)
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Insulinoma or other pancreatic β-cell tumors
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High insulin, high C-peptide, high proinsulin
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Non-insulinoma pancreatogenous hypoglycemia syndrome (NIPHS)
3. Critical Illness
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Sepsis → ↑ glucose utilization, ↓ gluconeogenesis
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Renal failure → ↓ insulin clearance, impaired gluconeogenesis
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Hepatic failure → ↓ glycogen stores and gluconeogenesis
4. Alcohol-Related Hypoglycemia
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Occurs 6–36 hrs after binge drinking, especially with poor oral intake
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Alcohol inhibits gluconeogenesis (via NAD⁺ depletion)
5. Reactive/Postprandial Hypoglycemia
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Occurs 1–3 hrs after eating
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More common in:
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Post–gastric bypass patients
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Early type 2 diabetes (exaggerated insulin response)
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6. Autoimmune Hypoglycemia
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Insulin autoimmune syndrome (Hirata’s disease)
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Antibodies against endogenous insulin
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Rare, more common in East Asian populations
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7. Factitious Hypoglycemia
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Surreptitious insulin or sulfonylurea use
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Labs:
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High insulin, low C-peptide (if exogenous insulin)
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High insulin, high C-peptide (if sulfonylurea)
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⚠️ Whipple’s Triad (for true hypoglycemia diagnosis)
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Symptoms of hypoglycemia
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Low plasma glucose (<55 mg/dL or 3.0 mmol/L)
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Relief of symptoms after glucose administration
📝 Summary – Hypoglycemia
🔍 Chief Complaint:
Episodes of dizziness, sweating, and confusion suggestive of hypoglycemia.
📋 Assessment – Hypoglycemia
Definition:
Hypoglycemia is defined as a blood glucose level <70 mg/dL (3.9 mmol/L). Clinically significant symptoms often appear when levels fall below this threshold.
Diagnosis is supported by Whipple’s Triad:
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Symptoms consistent with hypoglycemia
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Documented low plasma glucose
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Resolution of symptoms after glucose administration
🧠 Etiological Considerations:
1. Drug-Induced (Most Common)
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Exogenous insulin use (overdose or timing mismatch)
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Sulfonylureas (e.g., glibenclamide, glipizide)
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Meglitinides, quinine, β-blockers, salicylates
2. Endocrine Causes
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Adrenal insufficiency (↓ cortisol → ↓ gluconeogenesis)
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Hypopituitarism (↓ ACTH/GH)
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Insulinoma (pancreatic β-cell tumor; ↑ insulin, C-peptide, proinsulin)
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NIPHS (Non-insulinoma pancreatogenous hypoglycemia syndrome)
3. Critical Illness
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Sepsis, hepatic failure, renal failure
4. Alcohol-Induced Hypoglycemia
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Inhibits gluconeogenesis via NAD⁺ depletion
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Especially in patients with poor oral intake
5. Postprandial (Reactive) Hypoglycemia
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Occurs 1–3 hrs post-meal
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Seen in gastric bypass patients, early diabetes
6. Autoimmune Hypoglycemia
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Insulin autoimmune syndrome (rare, antibodies to endogenous insulin)
7. Factitious Hypoglycemia
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Surreptitious insulin or sulfonylurea use
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Labs:
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↑ insulin + ↓ C-peptide → exogenous insulin
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↑ insulin + ↑ C-peptide → sulfonylurea
🧪 Recommended Workup
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Plasma glucose (during symptoms)
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Insulin, C-peptide, proinsulin levels
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Sulfonylurea screen
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Cortisol (AM) and ACTH
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LFTs, RFTs
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β-hydroxybutyrate (↓ in hyperinsulinemic states)
🧭 Plan & Recommendations
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Record and document glucose levels during episodes
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Rule out medication-related causes
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Consider 72-hour fasting test if insulinoma is suspected
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Endocrinology referral if autoimmune or tumor etiology suspected
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Patient education on hypoglycemia recognition and management
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