Light Chain Multiple Myeloma Diagnosed via Urine Protein Discrepancy.

BACKGROUND

Discrepancies between routine urinalysis and 24-hour urine protein quantification often indicate atypical pathologies. Light chain multiple myeloma (LCMM) secretes free light chains and may present conflicting urine protein results.

METHODS

Laboratory analysis was performed, including a urinary immunoglobulin light chain test and a reduction assay to analyze the differences in proteinuria patterns.

RESULTS

The urinary immunoglobulin light chain test revealed a large amount of λ-type Bence Jones protein (6,660 mg/L), strongly suggestive of LCMM. This finding highlighted the presence of significant non-albumin proteinuria, which is characteristic of LCMM.

CONCLUSIONS

Systematic laboratory analysis and clinical collaboration are essential for accurate diagnosis. The identification of urinary protein discrepancies and the use of biochemical assays are crucial in resolving diagnostic challenges. By integrating clinical and laboratory findings, healthcare providers can achieve accurate diagnoses and improve patient care.