(1.09) Treat One But Injure Another: Adrenalectomy Unmasking Kidney Disease

Primary aldosteronism (PA) is due to aldosterone-producing adenomas or bilateral hyperaldosteronism in the adrenal glands that classically presents with hypertension and hypokalemia. Treatment of PA is a documented but lesser-known cause of chronic kidney disease (CKD) and hyperkalemia, which we will present in this case.



Case(s) Description :

58-year-old man with hypertension, diabetes, CKD, and PA treated with a right adrenalectomy one month ago presented for new asymptomatic hyperkalemia 5.2-6.1 mmol/L and creatinine rise from 1.4 mg/dL to 1.8 mg/dL. Prior PA evaluation showed elevated aldosterone:renin ratio, right lateralization on adrenal vein sampling, and hypokalemia 3.2-3.6 mmol/L. Since adrenalectomy, his creatinine progressed from 1.1-1.4 mg/dL to a new baseline of 1.6-1.9 mg/dL. ACTH stimulation, thyroid function tests, aldosterone levels, and renal ultrasound were within normal limits. Blood pressure and diabetes remained within goal. Patient did not have NSAID exposure, contrast studies, or changes in any urinary habits to suggest a specific etiology. Adrenalectomy was concluded to be the etiology of new onset hyperkalemia and decreased estimated glomerular filtration rate (eGFR).

Discussion :

This patient experienced progression of CKD and hyperkalemia after definitive treatment of PA with an adrenalectomy. There are a few proposed mechanisms of how PA induces kidney damage. One is that hyperfiltration from sodium retention and thus higher circulating volume to the kidneys causes accrued kidney damage. Another is aldosterone directly causes kidney damage. Hyperfiltration during PA masks the underlying decreased eGFR until the PA is treated. Both adrenalectomy and mineralocorticoid receptor antagonists in treating PA have demonstrated this outcome.

Treatment of PA is a documented but lesser-known cause of CKD that should be considered in initial workup for decreased eGFR. Patients with PA may have structural kidney damage despite normal eGFR due to hyperfiltration. Awareness of decline in eGFR after initiating treatment for PA is crucial in preventing poor outcomes.