The Utility of Elevated Serum Lactate Dehydrogenase in Current Clinical Practice.

OBJECTIVE Because of its wide tissue distribution, elevation of serum lactate dehydrogenase (LD) is a nonspecific finding. Although serum LD is still included in the prognosis and staging of metastatic melanoma and germ cell tumors, its nonspecificity has led to decreased usefulness. METHODS In this study, we analyzed the serum LD assays performed in a 726-bed hospital during a 1-year period and reviewed charts of patients with serum LD of >3 standard deviations (SD). RESULTS Of 312 patients with elevated serum LD, only 9 were patients with melanoma and germ cell tumors. The other 303 patients had other malignancies, chronic conditions, and sepsis. CONCLUSION Elevated serum LD (even >3 SD) is an extremely nonspecific finding that does not contribute to clinical management in a majority of patients. As such, serum LD testing should be retired from routine clinical order sets and restricted in use.