7677 A Novel Cause of Resistant Hypertension: Paraganglioma and Conn's Syndrome

Abstract Disclosure: H.F. Belal: None. R.M. Minns: None. J.M. Chehade: None. C.A. Koch: None. Background: Concomitant hyperaldosteronism (PA) and pheochromocytoma (PHEO) are extremely rare causes of hypertension. We present a novel case of concurrent PA and paraganglioma (PARA). Clinical Case: A 37 year old Ghanaian female with prior history of hypertension presented on referral with asymptomatic resistant hypertension and hypokalemia. Patient had developed hypokalemia (2.7 mEQ/L, 3.5-5.1 mEQ/L) after caesarean section for pre-eclampsia; discharged with hydralazine, labetalol and nifedipine. Labs on initial consultation showed hypokalemia 2.7 mEQ/L (3.5-5.1 mEQ/L), elevated plasma aldosterone 133.4 ng/dL (0.0-30.0 ng/dL), renin 0.815 ng/mL/hr (0.167-5.38 ng/mL/hr), elevated norepinephrine 1139 pg/mL (0-874 pg/mL), elevated chromogranin A 175.6 ng/mL (0.0-101.8 ng/mL); normal epinephrine, dopamine, DHEAS. Twenty-four-hour urine (volume 2,700 ml): elevated normetanephrine 967 mcg/24 hr (131-612 mcg/24 hr); normal urine metanephrine and free cortisol. Adrenal CT and MRI revealed left adrenal lesion 1.3 x 1.2 x 1.1 cm (pre-contrast Hounsfield Unit 13, absolute washout 74%), adjacent extra-adrenal 1.8 x 1.6 x 1.6 cm lesion near left renal vein chain (MRI T2 hyperenhancement) and no right adrenal lesions. She was started on prazosin 1 mg qd, spironolactone 25 mg qd, telmisartan 40 mg qd and potassium chloride 20 mEq TID for three weeks prior to left adrenalectomy and left retroperitoneal mass resection. Pathology revealed left adrenal cortical adenoma and left retroperitoneal PARA (positive synaptophysin, chromogranin, S100; preserved SDHB expression; Ki67 index 2%). Postoperatively blood pressure was controlled with amlodipine alone. Postoperative plasma/24 hour urine aldosterone, metanephrine, catecholamine and plasma renin, potassium were all normal. Conclusion: This is the first case, to our knowledge, of extra-adrenal PARA and Conn's Syndrome. Mao et al reviewed 7724 adrenal masses and found fifteen cases of concurrent PA and PHEO, but no concurrent PA and PARA [1]. Hypokalemia is rare yet more common (87%) in concurrent PA/PHEO than PA alone (28%)[1]. Management of concurrent PA and PHEO is primarily focused on medical bridging to a surgical cure while conserving adrenal function. As our case demonstrates, while exceedingly rare, it is important to work up adrenal masses to ensure that concurrent lesions are not missed. We propose a potential mechanism for concurrent lesions of PHEO/PARA could be concurrent germline mutations in genes triggering PA and in genes triggering PPGL syndromes.2References: 1. Mao JJ, Baker JE, Rainey WE, Young WF, Bancos I. Concurrent Pheochromocytoma and Primary Aldosteronism: A Case Series and Literature Review. J Endocr Soc. 2021;5(8):bvab107. 2. Kimura N, Koch CA, et al. Extraadrenal paragangliomas. pp.190-195. in: Lloyd RV et all. (Eds). WHO classification of tumors of endocrine organs (4th edition). IARC, Lyon 2017 Presentation: 6/2/2024