SHM Converge Scientific Abstract ePoster Gallery-Refractory Orthostatic Hypotension and Sinus Bradycardia Unmasking Central Adrenal Insufficiency With Suspicion for Al Amyloidosis

Pdf Summary

This case describes a patient with persistent orthostatic hypotension and sinus bradycardia in whom the cause was not explained by a primary cardiac conduction problem alone. The diagnostic reasoning favored a combination of central adrenal insufficiency, medication effects, and possible autonomic dysfunction from suspected AL amyloidosis.<br /><br />Key evidence supported secondary adrenal insufficiency: the cosyntropin test was abnormal, ACTH was low, electrolytes were largely near normal, and blood pressure improved after stress-dose hydrocortisone. The normal pituitary MRI suggested a functional or suppressive central process rather than a structural pituitary lesion. Coexisting thyroid abnormalities and menstrual irregularity raised concern for broader hypothalamic-pituitary axis involvement.<br /><br />Medication review was also important. Lithium, fluphenazine, and chronic opioid exposure could all contribute to bradycardia, hypotension, or endocrine suppression. Lithium and fluphenazine were stopped and aripiprazole was started, but orthostasis and bradycardia persisted, indicating these drugs were not the sole cause.<br /><br />A faint monoclonal lambda light-chain signal on urine immunofixation raised suspicion for AL amyloidosis, especially in the setting of autonomic symptoms, low-voltage ECG findings, and marked thyroid function variability. Although echocardiography was normal, this does not exclude early amyloid disease. Cardiac MRI was deferred to outpatient follow-up.<br /><br />Overall, the case emphasizes several clinical lessons: severe orthostasis can occur in central adrenal insufficiency even without major electrolyte abnormalities; heart-rate response and blood-pressure response help distinguish autonomic or endocrine causes from pacemaker-responsive bradycardia; thyroid test instability should prompt consideration of infiltrative or hypothalamic-pituitary disease; and even a subtle monoclonal protein signal may be clinically meaningful. The hospitalist’s role was central in integrating telemetry, orthostatic vitals, endocrine testing, medication changes, and specialty recommendations into a coherent inpatient plan.

Asset Subtitle

Casey Giblin

Meta Tag

Author List Casey Giblin, Sulaiman Paika

Category Clinical Vignettes

Concept Secondary Adrenal Insufficiency

Concept Orthostatic Hypotension

Concept Bradycardia

Concept AL Amyloidosis

Concept ACTH

Distinguished Non-Finalist

Presenter Organization Abrazo Arrowhead Hospital, AZ

Presenting Author Casey Giblin

Track Adult

Keywords

orthostatic hypotension

sinus bradycardia

central adrenal insufficiency

cosyntropin test

low ACTH

hydrocortisone response

medication-induced bradycardia

AL amyloidosis

autonomic dysfunction

hypothalamic-pituitary axis

Secondary Adrenal Insufficiency

Orthostatic Hypotension

Bradycardia

AL Amyloidosis

ACTH