Aldosterone-producing Multiple Micronodules With Several Different KCNJ5 Pathogenic Variants

Primary aldosteronism (PA) is the most common form of secondary hypertension. Recently, the genetic analysis of aldosterone-producing adenoma, a major cause of PA, has revealed several causative genes. Herein, we present a case of a 27-year-old Japanese female with PA. She was referred to our hospital with hypertension and hypokalemia (serum potassium, 2.8 mEq/L [2.8 mmol/L]). PA was diagnosed using several confirmatory tests. Computed tomography showed no apparent tumor in either adrenal gland. Adrenal vein sampling showed aldosterone overproduction in the right adrenal gland. Laparoscopic right adrenalectomy was performed, her blood pressure normalized, and the hypokalemia improved after surgery. Pathological findings revealed multiple aldosterone-producing micronodules with diameters of <5 mm. DNAs were extracted from 4 different micronodules and analyzed for KCNJ5. Two micronodules had a T158A pathogenic variant, 1 had a G151R pathogenic variant, and 1 had no pathogenic variant in the KCNJ5 gene. In summary, in our case, multiple nodules were present in 1 adrenal gland, and genetic heterogeneity was identified. No recurrence on the left side has been observed over 17 years following the surgery.