[Potentialisation of hyperkalemia effects by cinacalcet-induced hypocalcemia on dialysis]

We report on two patients on chronic hemodialysis, who presented with typical symptoms of hyperkalemia (lower limb paresia and characteristic electrocardiogram [ECG]) for an only mildly increased kalemia (6.1 and 6.2 mEq/L), values that are frequently seen in asymptomatic patients on chronic hemodialysis. Their common denominator was a concomitant hypocalcemia (7.5 et 6.4mg/dL) induced by cinacalcet treatment. Hypocalcemia has very likely precipitated the occurrence of clinical and electrocardiological manifestations of hyperkalemia. This observation is in agreement with previous publications showing that, in other clinical situations than the use of cinacalcet, hypocalcemia potentiates the effect of hyperkalemia on muscle membrane. Nephrologists should be aware of this complication and pay most attention in their patients on chronic dialysis with a calcemia less than 8mg/dL induced by cinacalcet treatment.