Isolated hyperphosphatemia as an early manifestation in asymptomatic multiple myeloma

Abstract

Usual presentation of multiple myeloma with symptoms like bone pains, renal failure or recurrent infections do not pose much of a diagnostic challenge, but difficulties arise when symptoms are vague and spurious results of laboratory investigations complicate the clinical picture. Hyperphosphatemia is usually observed in cases that have high disease burden (tumor lysis syndrome) or impaired renal functions; however its occurrence with solitary plasmacytoma or early stages (low burden) with preserved renal functions is unlikely and probably best explicable on account of pseudohyperphosphatemia- a laboratory error that results from interference in colorimetric estimation of serum phosphate because of existence of paraproteins in these patients. We, hereby, report a case where evaluation of asymptomatic hyperphosphatemia led to the final diagnosis of multiple myeloma.