21 PRIMARY ALDOSTERONISM IN A PATIENT WITH IDIOPATHIC INTRACRANIAL HYPERTENSION. (1st January 2005) - Dougherty, G. N.
Abstract : Background: Among adults with idiopathic intracranial hypertension (IIH, or pseudotumor cerebri), there is a preponderance of overweight, middle-aged women who often have a history of mild-moderate hypertension. Recently (Am J Med Sci 2002;324:45), two such women with IIH were found to have primary aldosteronism (PAL): one with adrenal adenoma; the other bilateral adrenal hyperplasia. Herein we report a third case of an overweight woman having established IIH and hypertension in whom the diagnosis of PAL was recently made. Case Presentation: A 49-year-old woman with a long-standing history of documented arterial hypertension and IIH (opening CSF pressure of 330 mm H2O; bilateral optic disk edema; severe headaches with visual field defects; without causation) was referred to the Cardiology Clinic because of poorly controlled hypertension (170/110 mm Hg) despite multiple medications. Episodic hypokalemia was seen in the past, but not at the time of referral. Cardiovascular examination was noncontributory, including the absence of an epigastric bruit. An aldosterone:renin ratio was obtained and found to be 72 (serum aldosterone 23 ng/dL: plasma renin activity 0.32 ng/mL/h; normal < 20). Abdominal CT scan did not reveal an adrenal adenoma. Selective sampling of the right (R) and left (L) adrenal (Ad) vein (V) revealed: (Table ) AdV aldosterone values < 800 ng/dL are considered normal. These findings indicate excessive aldosterone production from both adrenal glands likely due to bilateral hyperplasia. The patient was placed on an aldosterone receptor antagonist, spironolactone (75 mg po qd), with satisfactory control of her blood pressure. Central actions of aldosterone, expressed via its cytosolic receptor found in epithelial cells of the choroid plexus, include its influence on CSF K+ and blood pressure regulation. Conclusion: The presence of IIH in a middle-aged, overweight woman with arterial hypertension should raise the prospect of coexistent PAL. Screening for PAL includes the aldosterone:renin ratio while adrenal vein sampling provides a definitive diagnosis.