Neuropathy Autonomic Neuropathy 2 — Questions and Answers
Question 1: Pure autonomic failure (Bradbury-Eggleston syndrome) is characterized by which pathological finding?
- Lewy bodies in peripheral autonomic neurons (Correct answer)
- Demyelination of vagus nerve
- Inflammatory infiltrate in sympathetic ganglia
- Amyloid deposits in dorsal root ganglia
Correct answer: Lewy bodies in peripheral autonomic neurons
Pure autonomic failure is associated with Lewy body accumulation in peripheral autonomic neurons without central nervous system involvement.
Question 2: Gustatory sweating (Frey's syndrome) after eating is a form of autonomic neuropathy associated with damage to which nerve?
- Facial nerve
- Auriculotemporal branch of trigeminal nerve (Correct answer)
- Glossopharyngeal nerve
- Hypoglossal nerve
Correct answer: Auriculotemporal branch of trigeminal nerve
Frey's syndrome results from aberrant reinnervation of the auriculotemporal nerve, causing sweating during eating instead of salivation.
Question 3: Which medication class is first-line for symptomatic orthostatic hypotension in autonomic neuropathy?
- Beta-blockers
- ACE inhibitors
- Midodrine (alpha-1 agonist) (Correct answer)
- Diuretics
Correct answer: Midodrine (alpha-1 agonist)
Midodrine, an alpha-1 adrenergic agonist, increases peripheral vascular resistance and is first-line for symptomatic orthostatic hypotension.
Question 4: Diabetic neurogenic bladder due to autonomic neuropathy first manifests as which urodynamic abnormality?
- Detrusor overactivity (urgency incontinence)
- Impaired bladder sensation and increased capacity (Correct answer)
- Bladder neck obstruction
- External sphincter dyssynergia
Correct answer: Impaired bladder sensation and increased capacity
Early diabetic neurogenic bladder shows impaired sensation, increased bladder capacity, and reduced detrusor contractility.
Question 5: Multiple system atrophy (MSA) is distinguished from pure autonomic failure by which feature?
- Presence of orthostatic hypotension
- Involvement of the central nervous system with cerebellar or parkinsonian features (Correct answer)
- Onset after age 70
- Response to fludrocortisone treatment
Correct answer: Involvement of the central nervous system with cerebellar or parkinsonian features
MSA involves both autonomic failure and central nervous system degeneration (cerebellar ataxia or parkinsonism), unlike pure autonomic failure.
Question 6: Which gastrointestinal motility drug is commonly used to treat diabetic gastroparesis?
- Ondansetron
- Metoclopramide (Correct answer)
- Loperamide
- Cholestyramine
Correct answer: Metoclopramide
Metoclopramide is the only FDA-approved medication for diabetic gastroparesis and works as a dopamine antagonist and prokinetic agent.
Neuropathy Autonomic Neuropathy 2
Pure autonomic failure (Bradbury-Eggleston syndrome) is characterized by which pathological finding?