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Equations

Scores

Transtubular Potassium Gradient (TTKG)

  Units: US SI
Serum Osm mOsm/L
Urine Osm mOsm/L
Serum K mg/dL
Urine K mg/dL
TTKG

Transtubular Potassium Gradient (TTKG) = (POsm * UPotassium ) / (PPotassium x UOsm)

Note that this formula is valid only when Uosm >300 and UNa >25. This test can help determine the source of potassium imbalance.