title: Resolution of hypertension during pregnancy in familial hyperkalemia and hypertension with the WNK4 Q565E mutation.
abstract: OBJECTIVE
  Secondary hypertension during pregnancy usually carries high maternal and fetal morbidity and mortality rates. A rare form of monogenic hypertension is familial hyperkalemia and hypertension, which is caused by mutations in the kinases WNK1 or WNK4 and other unknown molecular defects. The purpose of the study was to examine the course of pregnancy in hypertensive women with familial hyperkalemia and hypertension.
  
  
  METHODS
  We prospectively studied 2 pregnancies of a woman with familial hyperkalemia and hypertension and the Q565E WNK4 mutation (pregnancies 1 and 2) and retrospectively studied the course of 2 pregnancies in another woman who was an affected member of this largest family described in the literature.
  
  
  RESULTS
  Both women had hypertension (170-190/105-110 mm Hg), hyperkalemia (5.3-6.0 mmol/L), and hypercalciuria, all of which were well controlled by thiazides. During pregnancies, thiazides were discontinued; throughout the pregnancy, the blood pressure remained normal at 120 to 130/75 to 85 mm Hg; however, hyperkalemia and hypercalciuria, which were documented in pregnancies 1 and 2, persisted. Renin and aldosterone levels (which were measured in pregnancies 1 and 2) rose towards their end. Four normal infants were born. A woman with familial hyperkalemia and hypertension of unknown molecular defect who had 2 pregnancies with hypertension exacerbation and premature deliveries was described previously.
  
  
  CONCLUSIONS
  In familial hyperkalemia and hypertension with the WNK4 mutation, pregnancy ameliorates hypertension; however, hyperkalemia and hypercalciuria persist. This dissociation may shed light on the pathogenesis of familial hyperkalemia and hypertension, on pregnancy-related hypertension, and on the mechanism of action of WNK4 kinase, a major regulator of cellular ion transport.
authors.affiliation: Department of Medicine E,Sheba Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Hashomer, Israel.
authors.forename: Haim
authors.initials: H
authors.lastname: Mayan
authors.forename: Meir
authors.initials: M
authors.lastname: Mouallem
authors.forename: Miriam
authors.initials: M
authors.lastname: Shaharabany
authors.forename: Rachel
authors.initials: R
authors.lastname: Pauzner
authors.forename: Zvi
authors.initials: Z
authors.lastname: Farfel
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D006947:Hyperkalemia / Q000235:genetics* / Q000503:physiopathology; D006973:Hypertension / Q000235:genetics* / Q000503:physiopathology; D008875:Middle Aged; D009154:Mutation; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000503:physiopathology*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*
chemical_list: D017346:Protein Serine-Threonine Kinases; C433806:WNK4 protein, human