Adachi Masanori, Muroya Koji, Asakura Yumi, Sugiyama Kenji, Homma Keiko, Hasegawa Tomonobu
Department of Endocrinology and Metabolism, Kanagawa Children's Medical Center, Yokohama, Japan.
Horm Res Paediatr. 2014;82(2):138-42. doi: 10.1159/000358197. Epub 2014 May 10.
Familial hyperaldosteronism type III (FH-III) is a rare autosomal dominant disease for which five missense mutations in KCNJ5 have been identified. FH-III has a wide phenotypic variability from spironolactone-responsive hyperaldosteronism to massive adrenal hypertrophy with drug-resistant hypertension. This variation has mainly been attributed to genotype, because, in contrast to other genotypes (G151R, T158A, I157S, and Y152C), (1) FH-III patients with G151E have shown milder phenotype, and (2) G151E-harboring cells were found to have rapid lethality due to much larger sodium conductance of the encoded channel (Kir3.4), which prevents adrenal hypertrophy.
Here we describe the clinical course of a sporadic case of FH-III, with de novo G151R mutation.
The patient developed polyuria at around 1.5 years of age and developed hypertension and hypokalemia by 4 years of age. Thereafter, spironolactone treatment successfully ameliorated hyperaldosteronism for 7 years with no discernible adrenal enlargement.
Diverse clinical severity in FH-III cannot be defined solely by KCNJ5 genotype.
III型家族性醛固酮增多症（FH-III）是一种罕见的常染色体显性疾病，已在KCNJ5基因中鉴定出5个错义突变。FH-III具有广泛的表型变异性，从螺内酯反应性醛固酮增多症到伴有耐药性高血压的巨大肾上腺肥大。这种变异主要归因于基因型，因为与其他基因型（G151R、T158A、I157S和Y152C）相比，（1）携带G151E的FH-III患者表现出较轻的表型，（2）发现携带G151E的细胞由于编码通道（Kir3.4）的钠电导大得多而具有快速致死性，这可防止肾上腺肥大。
在此我们描述了一例散发的FH-III病例的临床过程，该病例存在新发的G151R突变。
该患者在1.5岁左右出现多尿，4岁时出现高血压和低钾血症。此后，螺内酯治疗成功改善醛固酮增多症达7年，且未发现肾上腺明显增大。
FH-III的不同临床严重程度不能仅由KCNJ5基因型来定义。
