Examkin

Soru

Zorluk: OrtaEndocrinology and Metabolism

A 45-year-old patient is undergoing evaluation for secondary causes of hypertension and electrolyte abnormalities. The physician orders a plasma aldosterone concentration and plasma renin activity panel. Match the following laboratory profiles to their most likely underlying etiology.

  • Elevated aldosterone, suppressed renin, hypokalemiaAldosterone-producing adrenal adenoma
  • Elevated aldosterone, elevated renin, normokalemiaUnilateral renal artery fibromuscular dysplasia
  • Suppressed aldosterone, suppressed renin, hypokalemiaChronic consumption of authentic licorice
  • Suppressed aldosterone, elevated renin, hyperkalemiaAutoimmune adrenalitis

Cevap

Elevated aldosterone/suppressed renin matches adrenal adenoma. Elevated aldosterone/elevated renin matches fibromuscular dysplasia. Suppressed aldosterone/suppressed renin matches licorice consumption. Suppressed aldosterone/elevated renin matches autoimmune adrenalitis.
Matching these conditions correctly requires analyzing the physiological feedback loop of the RAAS pathway. Autonomous mineralocorticoid activity (whether from an adenoma or an exogenous source like licorice) will always suppress renin. If the aldosterone itself is the source, aldosterone is high (primary hyperaldosteronism). If something else is acting at the mineralocorticoid receptor, both renin and aldosterone are suppressed (apparent mineralocorticoid excess). Conversely, if the system is driven by renal hypoperfusion, renin is high, driving aldosterone high. If the adrenal gland fails, aldosterone is low, leaving renin unsuppressed and highly elevated.

Adım Adım Çözüm

1
Determine if the aldosterone and renin levels are moving in the same or opposite directions.
Opposite directions suggest a primary adrenal issue; same directions suggest a secondary (renin-driven) or exogenous issue.
This establishes whether the pathology originates in the adrenal gland or upstream in the RAAS pathway.
2
Evaluate the 'Elevated aldosterone, suppressed renin' profile.
Matches Primary Hyperaldosteronism (Aldosterone-producing adrenal adenoma).
Autonomous production of aldosterone causes negative feedback on renin.
3
Evaluate the 'Elevated aldosterone, elevated renin' profile.
Matches Secondary Hyperaldosteronism (Unilateral renal artery fibromuscular dysplasia).
Primary increase in renin (due to perceived renal hypoperfusion) drives the elevation in aldosterone.
4
Evaluate the 'Suppressed aldosterone, suppressed renin, hypokalemia' profile.
Matches Apparent Mineralocorticoid Excess (Chronic consumption of authentic licorice).
An alternative mineralocorticoid source (cortisol bypassing degraded 11b-HSD2) suppresses both native renin and aldosterone while still causing hypokalemia.
5
Evaluate the 'Suppressed aldosterone, elevated renin, hyperkalemia' profile.
Matches Primary Adrenal Insufficiency (Autoimmune adrenalitis).
Primary failure of the adrenal gland eliminates aldosterone, removing negative feedback and causing profound renin elevation due to volume depletion.

Anahtar Kavram

Interpretation of Renin-Angiotensin-Aldosterone System (RAAS) laboratory profiles
Bu soruyu puanla

Konular

Endocrinology and Metabolism

Bu konudan daha fazla soru