Gitelman's Syndrome

At a Glance

The clinical presentation of Gitelman’s syndrome is often nonspecific. There may be evidence of polyuria and polydipisa, salt craving, muscle cramping, and malaise, as well as growth impairment in children. The usual age of diagnosis is mid- to late-teens and young adult. This is in contrast to that of Bartter syndrome, which may mimic Gitelman’s syndrome but presents in the first few years of life.

What Tests Should I Request to Confirm My Clinical Dx? In addition, what follow-up tests might be useful?

Plasma laboratory findings of hypokalemia, hypomagnesemia, and metabolic alkalosis with associated urinary wasting of both Mg and K.(Table 1)

Table 1
hypokalemic metabolic alkalosis with low Mg High levels of urine Mg and K Genetic Testing may be helpful

Are There Any Factors That Might Affect the Lab Results? In particular, does your patient take any medications – OTC drugs or Herbals – that might affect the lab results?

This disease may mimic Bartter syndrome or diuretic use (abuse).

What Lab Results Are Absolutely Confirmatory?

Lab results that are absolutely confirmatory include:

low potassium and magnesium

metabolic alkalosis

high levels of urine Mg and K

What Tests Should I Request to Confirm My Clinical Dx? In addition, what follow-up tests might be useful?

Follow-up testing is needed to confirm normalization of K and Mg with oral supplements