Significance of Increased Alkaline Phosphatase and Lactate Dehydrogenase Activities Coincident with Normal Serum Bilirubin

Abstract

Abstract The diagnostic significance of a simultaneous increase in the activities in serum of alkaline phosphatase (ALP) and lactate dehydrogenase (LD) with normal serum bilirubin has been studied in 202 hospital patients. Of these cases, 28% were due to congestive heart failure or myocardial infarction, 25% to malignancy, and 16% to various hepatobiliary disorders. Fewer cases were due to bone fractures with large hematomas, pulmonary embolism, renal failure, or malabsorption syndrome. These biochemical changes in the patients with malignancies did not necessarily signify the presence of hepatic or bony metastases. Hypercalcemia occurred only in this group of patients, and was thus of considerable diagnostic importance. Neither the other tests performed with the SMA 12/60 or the ratios between LD and ALP gave diagnostically useful results.