Chronic hypokalaemia in a hypertensive patient.
Bottom Line: Hypokalaemia in hypertensive patients is a 'red flag' bringing to mind various classic secondary and genetic causes related to both hypokalaemia and hypertension.We encountered a patient who had an unusual cause for his disturbance that, to our knowledge, has not been described in hypertensive patients.
Affiliation: HELIOS-Klinikum, Berlin, Germany.
Hypokalaemia in hypertensive patients is a 'red flag' bringing to mind various classic secondary and genetic causes related to both hypokalaemia and hypertension. We encountered a patient who had an unusual cause for his disturbance that, to our knowledge, has not been described in hypertensive patients.
No MeSH data available.
Related in: MedlinePlus
Mentions: Gitelman et al. described such a syndrome in 1966 . They observed three patients with hypokalaemia, hypomagnesaemia, mild metabolic alkalosis and potassium wastage. Two were sisters and the parents were related. This state-of-affairs resulted in a more careful family history in our patient and so we constructed a family tree (Figure 1). We found that our patient had married a first cousin and that three of his wife's brothers were dead. We could not trace the tree to back generations. We believed our patient had a constellation consistent with Gitelman's syndrome. We have no explanation for any kidney stones since our affected persons should excrete less calcium and more magnesium, which should protect from kidney stones. Our chief-of-service pointed out that Cruz et al.  had found Gitelman's mutations in the Na–Cl cotransporter earlier and that Gitelman's mutations protected from hypertension, which was exactly the opposite of what our patient had. In addition, Cruz et al.  observed that the NCCT genotype was a significant predictor of blood pressure, with homozygous mutant family members having significantly lower age- and gender-adjusted systolic and diastolic blood pressure than those of their wild-type relatives. Heterozygous children, but not adults, had significantly lower blood pressure than those of the wild-type relatives. Their findings provided a formal demonstration that inherited mutations that impair renal salt handling lower blood pressure in humans. So what? Our patient was hypertensive and not hypotensive? The words ‘hypertension’ and Gitelman's syndrome occur in a sole report involving central nervous system increases in blood pressure .
No MeSH data available.