No abstract

As part of the Nordic Reference Interval Project we present reference intervals for alanine transaminase (ALT), aspartate transaminase (AST), creatine kinase (CK), lactate dehydrogenase (LD), alkaline phosphatase (ALP), gamma-glutamyltransferase (GT), amylase (AMY) and pancreatic type of AMY in blood of adult males and females. A total of 3036 reference persons, all of whom considered themselves to be in good health, were recruited by 102 Nordic clinical biochemical laboratories. Exclusions were undertaken on the basis of predefined biochemical and clinical criteria. Enzyme activities in serum and plasma were measured in the different laboratories using various commercially available routine measurement systems at 37 degrees C. Only results obtained with the International Federation of Clinical Chemistry (IFCC) compatible measuring systems were selected for estimation of the enzyme reference intervals. The final number of results on each enzyme varied from 459 (LD) to 2300 (ALT). The 2.5 and 97.5 percentile reference limits were calculated by a non-parametric method in accordance with the IFCC recommendations, using the Refval 4.0 data program. Statistical partitioning testing was undertaken to decide whether the reference intervals ought to be partitioned according to gender and/or age. For most of the enzymes, but not for all, the upper reference limits were found to be higher than those that have been in general use until now.

No abstract

ExtractAn infant suffering from metabolic acidosis attributable to hyperlactatemia (6.1 mmol/liter) accompanied by hyperalaninemia (1 mmol/literj and hyperserinemia (0.6 mmol/literj is described. The urinary excretion of lactate and pyruvate was greatly elevated; the lactate to pyruvate ratio was normal. The urine showed low levels of citrate, isocitrate, and cis-aconitate, and low or normal levels of a-oxoglutarate, succinate, malate, and methylmalonate. Aspartate was slightly elevated in serum and urine, indicating a corresponding increase of its a-ketoacid oxaloacetate. These patterns of organic acids and amino acids suggested an in vivo defect in the oxidation of pyruvate. Fibroblasts cultured from skin biopsy from the patient metabolized radioactive pyruvate (final concentration 0.04-2 mmol/liter) to CO, at rates from 5 to 17% of that of fibroblasts from normal control subjects. Enzyme studies with fibroblast sonicates revealed a severe deficiency of the pyruvate dehydrogenase complex (about 8% of normal), and this error was localized to the first unit of the complex, i.e., the pyruvate dehydrogenase (about 4% of normal). Fibroblasts from both parents metabolized pyruvate to CO, at a slightly reduced rate, suggesting parental heterozygosity.

No abstract