Spurious electrolyte disorders: a diagnostic challenge for clinicians.

Spurious electrolyte disorders refer to an artifactually elevated or decreased serum electrolyte values that do not correspond to their actual systemic levels. When a clinician is confronted with a case of electrolyte disturbance, the first question should be whether it is an artifact. Spurious electrolyte disorders (pseudohyponatremia, pseudohypernatremia, pseudohypokalemia, pseudohyperkalemia, pseudohypomagnesemia, pseudohypophosphatemia, pseudohyperphosphatemia, pseudohypocalcemia and pseudohypercalcemia) are not infrequently observed in clinical practice. The recognition that an electrolyte disturbance may be an artifact may prevent inappropriate therapeutic interventions that could potentially have unfavorable outcomes. Clinicians must be alert to the possibility of spurious laboratory abnormalities when faced with conflicting laboratory values or measurements that are discordant with the clinical presentation. Moreover, in the presence of conditions that predispose to spurious electrolyte disorders, the normal measured electrolyte levels should raise the suspicion that true electrolyte disorders may be present.