Figure 3.

Patients with variants in MT-TI or MT-TF have Gitelman syndrome-like electrolyte abnormalities. (A–G) Serum and urinary electrolyte values in patients by pathogenic variant. Dotted lines represent upper and lower limits of normal. For the fractional excretion of magnesium (FEMg) and urinary calcium excretion, lower limits of normal were not available; therefore, only the upper limit of normal is depicted in panels (B) and (D). Upper limit of normal for FEMg applies to hypomagnesemic individuals only and these are on the basis of Elisaf et al.⁷⁵ Black circles (•), without supplementation; open circles (^), with supplementation; gray circle in panel (D), a child (individual 3.III.2); upper limit of normal for this age is 2.2 mmol/mmol Ca²⁺/creatinine. FEMg is calculated by: serum creatinine×urinary magnesium/(serum magnesium×urinary creatinine)×100%.