Hypoglycemia

From Anvita Health Wiki

Contents 1 More Specific Terms 2 Introduction 3 Etiology 4 Clinical-manifestations 5 Laboratory 6 Radiology 7 Complications 8 Differential-diagnosis 9 Management 10 More General Terms 11 Additional Terms 12 References

More Specific Terms

• familial hyperinsulinemic hypoglycemia; persistent hyperinsulinemic hypoglycemia of infancy (PHHI); congenital hyperinsulinism
• leucine-induced hypoglycemia; leucine-sensitive hypoglycemia of infancy

Introduction

• Also see Whipple's triad

Etiology

• reactive:

• within 1st 5 hours after eating
• infrequent, over (self diagnosed);

• rarely true hypoglycemia ( glucose < 50 mg/dL)

• gastrointestinal surgery

• vagotomy, pyloroplasty, gastrectomy, gastrojejunostomy

• early diabetes (unusual)
• idiopathic "functional" hypoglycemia

• fasting:

• more than 5 hours after eating
• more common form of hypoglycemia
• pharmacologic agents

• insulin (including surreptitious injection)
• oral hypoglycemics
• quinine ( intravenous for cerebral malaria)
• alcohol impairs gluconeogenesis
• propranolol (often in hemodialysis patients)
• salicylates (mostly children)
• pentamidine in undernourished AIDS patients
• disopyramide ( Norpace)

• elderly non- diabetics with liver or renal failure

• haloperidol

• renal insufficiency
• severe malnutrition
• pregnancy (generally asymptomatic)
• hepatic failure: cirrhosis
• septicemia
• insulinoma:

• may be benign or malignant

• may occur as component of MEN-1

• nesidioblastosis in children

• hormone deficiency

• adrenal insufficiency (more common in children)
• growth hormone deficiency
• thyroxine deficiency
• catecholamine deficiency
• glucagon deficiency (unusual)

• abdominal tumors

• mesenchymal tumor: abdomen, pelvis, thorax
• carcinoma of the adrenal, kidney, GI tract
• hepatoma
• may be secondary to IGF-2

• glycogen storage disease
• systemic carnitine deficiency
• congestive heart failure
• leukemia may result in artifactual hypoglycemia

• leukocyte consumption of glucose, use NaF tubes

• anti-insulin & anti- insulin receptor antibodies

Clinical-manifestations

• plasma glucose levels < 50 mg/dL usually, but not always produce hypoglycemia

• fasting young, healthy women may have serum glucose levels < 50 mg/dL without symptoms
• poorly controlled diabetics may experience symptoms of hypoglycemia > 70 mg/dL

• cholinergic symptoms

• sweating

• adrenergic symptoms

• anxiety
• hunger
• diaphoresis
• tachycardia
• tremulousness
• PVC's
• irritability
• hyperthermia
• palpitations
• hypothermia

• neurologic symptoms

• headache
• behavioral changes
• cognitive change
• seizures
• coma
• hemiparesis
• aphasia
• visual changes
• Babinski's sign

• * syncope is NOT a manifestation

Laboratory

• serum glucose

• hypoglycemia is defined as laboratory serum glucose or plasma glucose < 50 mg/dL (not portable monitor)
• fasting serum glucose of < 50-60 mg/dL may occur in asymptomatic normal people [3]

• known diabetic

• serum alcohol
• cortisol level
• liver function tests
• urea nitrogen
• serum creatinine

• non- diabetic

• serum insulin

• serum insulin > 6 mU/ mL in association with serum glucose < 50 mg/dL in males & < 40 mg/dL in females indicates hyperinsulinemia

• insulin antibodies
• C-peptide levels (obtain when glucose is < 50 mg/dL)

• C-peptide level > 0.2-0.4 nM suggests a beta-cell lesion ( insulinoma)
• plasma insulin in the absence of plasma C-peptide suggests surreptitious injection of insulin

• sulfonylurea level if serum insulin & serum C-peptide are inappropriately increased for degree of hypoglycemia
• anti- insulin receptor antibodies if insulin is increased, no insulin antibodies & C-peptide is normal or low

• 72 hour fast

• increased serum insulin & serum C-peptide in the absence of insulin antibodies & measurable serum sufonylureas indicates insulinoma

• 5 hour glucose tolerance test is rarely used
• increased serum insulin-like growth factor-2 ( serum IGF-2) suggests mesenchymal tumor
• 5 hour glucose tolerance test: (NOT useful)

• serum glucose < 50 mg/dL with symptoms of hypoglycemia occurs commonly in normal individuals

Radiology

• CT of abdomen not routinely indicated unless carcinoma suspected

Complications

• even mild hypoglycemia associated with increased mortality in critically ill patients
• severe hypoglycemia is associated with increased risk of cardiovascular disease & death [6]

Differential-diagnosis

• self diagnosed hypoglycemia

• anxiety
• panic attacks
• hyperventilation
• pheochromocytoma

• neurologic manifestations of hypoglycemia

• seizure disorder
• psychosis
• drug or alcohol intoxication
• transient ischemic attack or stroke
• etiologies of coma

Management

• acute therapy

• 6-12 oz of juice or non diet soda if awake
• 50 mL of 50% glucose IV: followed by 10% glucose IV until patient is able to eat
• repeated boluses of 50% glucose may be required
• fructose is alternative to glucose
• glucagon 1 mg IV or IM if unresponsive

• treatment of underlying disorder

• pseudo (self diagnosed) hypoglycemia

• high protein diet, frequent meals

• discontinue use of alcohol
• discontinue or decrease sulfonylureas

• substitute with metformin or shorter-acting sulfonylurea (i.e. glypizide)

• adjust insulin dose
• discontinue other offending pharmacologic agents
• patients with renal failure not on dialysis require higher carbohydrate diets with more frequent feedings
• patients on dialysis may benefit from a decrease in dialysis glucose concentration
• patients with hepatic failure require continuous intravenous glucose until recovery has begun
• malnutrition requires adequate nutrients
• cortisol replacement for adrenal insufficiency
• insulinomas & mesenchymal tumors

• consult endocrinology & surgery
• non operable insulinomas may be managed with

• diazoxide
• thiazides

• tumor debulking & chemotherapy for mesenchymal tumors

• counseling may benefit anxiety disorder

More General Terms

• sign/symptom

Additional Terms

• glucose in serum/plasma
• hyperglycemia
• hypoglycemic agent
• Whipple's triad (Whipple's criteria)

References

1. Saunders Manual of Medical Practice, Rakel (ed), WB Saunders, Philadelphia, 1996, pg 668-670
2. Mayo Internal Medicine Board Review, 1998-99, Prakash UBS (ed) Lippincott-Raven, Philadelphia, 1998
3. Medical Knowledge Self Assessment Program (MKSAP) 11, 14, 15, American College of Physicians, Philadelphia 1998, 2006, 2009
4. Egi M et al Hypoglycemia and outcome in critically ill patients. Mayo Clin Proc 2010 Mar; 85:217. PMID: [1]
5. Neonatal hypoglycemia Maine Medical Center (MMC) [2]
6. Zoungas S et al, Severe Hypoglycemia and Risks of Vascular Events and Death N Engl J Med 2010; 363:1410-1418 <PubMed> PMID: [3] <Internet> [4]
7. National Guideline Clearinghouse Neonatal hypoglycemia: initial and follow up management. Barbara Bush Children's Hospital at Maine Medical Center ngc-guideline: [5]
   - Evaluation and management of adult hypoglycemic disorders: an Endocrine Society clinical practice guideline. The Endocrine Society ngc-guideline: [6]

hypoglycemia