Approach to a patient with dizzy spells

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Approach to a patient with dizzy spells

• Rola Zamel
• R5, Endocrine

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• Consult
• 40 YOM with recurrent dizzy spells that improves
  after eating
• ? Hypoglycemia.

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• Definition of Dizziness
• "Dizziness" is a nonspecific term often used by
  patients to describe symptoms.
• The most common disorders lumped under this term
  include
• 1- Vertigo
• 2- Nonspecific "dizziness"
• 3- Presyncope
• 4- Disequilibrium
• 5- Other rare causes

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• Causes of dizziness
• 1- Vertigo
• - 50 of patients with dizziness seen in
  different settings primary care, dizziness
  clinic and ER
• Peripheral
• Central
• Migraine
• Non-specific

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• 2- Psychiatric disorder
• - 10 in ER, 15 in primary care and 20 in
  dizziness clinic

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• 3- Presyncope
• 5-15
• Causes of presyncope/syncope
• Cardiovascular
• arrhythmic causes
• non arrhythmic HOCM, AS

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• Non-Cardiovascular
• Reflex mechanisms
• Orthostatic hypotension
  ( Pheochromocytoma and adrenal
  insufficiency)
• Undiagnosed seizures
• Improperly diagnosed syncope confusional
  states eg. d/t hypoglycemia, stroke

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• drug induced loss of consciousness (
  alcohol, illicit drugs)
• - Rare causes (Carcinoid)
• - Syncope of unknown origin 50 of patients
  presenting to the hospital

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• 4- Others
• - Disequilibrium
• - Hyperventilation
• - Multicausal
• - Unknown

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• Evaluation
• 1- Hx/ PE
• Confirm Dx
• Cause
• Complication

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• Labs
• Hypoglycemia
• Evaluation and management of hypoglycemia is
  recommended only in patients in whom Whipples
  triad is documented
• J Clin Endocriol Metab, March 2009, 94 (3)709-728

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• Whipples triad
• 1- Symptoms, signs or both consistent with
  hypoglycemia
• 2- Low plasma glucose concentration
• 3- Resolution of those symptoms or signs after
  the plasma glucose concentration is raised

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• In patients with hypoglycemia without diabetes
  apply the following strategy
• A- Pursue clinical clues (Hx, P/E, labs) to
  potential hypoglycemic etiologies- drugs,
  critical illnesses, hormone deficiencies,
  nonislet cell tumors

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• B- In absence of above, DDx include exogenous and
  endogenous hyperinsulinemia ???
• 1- measure plasma glucose, insulin, C-peptide,
  proinsulin and B-hydroxybutyrate concentrations
  and screen for OHA during an episode of
  spontaneous hypoglycemia
• 2- and observe the plasma glucose response to iv
  injection of 1 mg glucagon
• 3- also measure insulin Abs

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• 4- when spontaneous hypoglycemic episode cannot
  be observed, formally recreate the circumstances
  in which symptomatic hypoglycemia is likely to
  occur, i.e. during a fast of up to 72h or after a
  mixed meal

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• The findings of symptoms, signs or both with
  plasma concentrations of
• gluc lt 3.0 mmol/L,
• insulin of at least 3.0 uU/ml,
• C-peptide of at least 0.6ng/ml and proinsulin
  of at least 5.0pmol/L document endogenous
  hyperinsulinism
• - B-hydroxybutyrate levels of 2.7 mmol/L or less
  and an increase in plasma glucose of at least
  25mg/dl after iv glucagon indicate mediation of
  the hypoglycemia by insulin ( or by an IGF)

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• 5- In patients with documented fasting or
  postprandial endogenous hyperinulinemic
  hypoglycemia, negative screening for OHA, and no
  circulating insulin Abs ?? localize insulinoma
  CT, MRI, transabdominal or endoscopic US and if
  necessary selective pancreatic arterial calcium
  injections with measurements of hepatic venous
  insulin levels

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• Carcinoid syndrome
• Definition
• A constellation of symptoms mediated by
  various humoral factors elaborated by some
  carcinoid tumors
• - Usually with intestinal carcinoid if liver mets
  or in bronchial or extra intestinal carcinoid

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• CF
• 1- Episodic flushing is the clinical hallmark of
  the carcinoid syndrome
• Occurs in 85 of patients
• Typical flush starts suddenly and lasts 30 sec-30
  min
• Typically involve face, neck and upper chest and
  is associated with mild burning sensation

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• Severe flushes are accompanied by a fall in blood
  pressure and rise in pulse rate
• Flushes can be spontaneous or provoked by eating,
  EtOH
• 2- Venous telangiectasia late in the disease,
  mostly on the nose, upper lip and malar areas
• 3- Secretory diarrhea in 80 of patients, not
  related to the flushing episodes

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• 4- Bronchospasm 10-20 of patients with
  carcinoid syndrome, usually during flushing
  episodes
• 5- Cardiac valvular lesions

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• Diagnosis of Carcinoid syndrome
• The most useful initial diagnostic test for the
  carcinoid syndrome is to measure 24-hour urinary
  excretion of 5-HIAA, which is the end product of
  serotonin metabolism
• 75 sensitive and 100 specific

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• 3- Screen for pheo and adrenal insufficiency if
  indicated

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• References
• 1- Uptodate Approach to patient with dizziness
• 2- JCEM, Evaluation and management of adult
  hypoglycemic disorder An Endocrine Society
  clinical practice guideline
• 3- Uptodate Clinical features of the carcinoid
  syndrome