Creatine kinase-MB mass concentration versus creatine kinase-B activity for the detection of acute myocardial infarction in patients with slightly elevated total creatine kinase activity in serum.

Objective: The diagnostic value of creatine kinase-MB mass concentration (CK-MB mass) was compared with that of creatine kinase-B (CK-B) activity in patients with suspected acute myocardial infarction (AMI) but with total serum CK activity only slightly above the reference range.

Design: One hundred consecutive blood samples with total CK activity between 120 and 360 U l-1 and CK-B activity > or = 9 U l-1 were analysed. Electrophoresis of CK isoenzymes was also performed.

Recurrent transient hyperphosphatasemia of infancy in an adult.

We report a case of recurrent transient hyperphosphatasemia in a 29-year-old man with immune deficiency. He had serum alkaline phosphatase (ALP; EC 3.1.

Local immunoglobulin production in synovial tissue in patients with Lyme borreliosis.

A study was made to find out whether immunoglobulins are produced locally in synovial tissue in patients with Lyme borreliosis. Synovial fluid specimens from six patients with Lyme borreliosis were compared with those from 25 patients with rheumatoid arthritis, psoriatic arthritis, unspecified oligoarthritis or arthrosis (control group). Agarose electrophoresis revealed local oligoclonal IgG and IgM bands in the synovial fluid of two patients with Lyme borreliosis, but no local bands were observed in the control group.

Further characterization of a heat-stable alkaline phosphatase with low sensitivity to L-phenylalanine.

A heat-stable alkaline phosphatase, hitherto found in two families with inherited hyperphosphatasemia, was further characterized. The enzyme was similar to serum placental alkaline phosphatase from pregnant women concerning its apparent affinity constant (Km) for 4-nitrophenyl phosphate and its reactivity with H7 monoclonal anti-placental alkaline phosphatase (PLAP) antibodies, but different in the following respects: it exhibited greater heat stability, a higher pH optimum, lower sensitivity to inhibition by L-phenylalanine, and no reactivity with C2 monoclonal anti-PLAP antibodies. The low sensitivity to L-phenylalanine suggests that the enzyme might correspond to a rare phenotype of placental alkaline phosphatase found in human term placenta.

Inherited occurrence of a heat stable alkaline phosphatase in the absence of malignant disease.

We describe a family with an inherited persistent elevation of serum alkaline phosphatase activity in the absence of malignant disease, observed for at least 15 yr. Isoenzyme studies revealed that this increased activity was due to an enzyme which showed similarities to serum placental alkaline phosphatase from pregnant women having the following properties: high heat stability; reactivity to anti-placental alkaline phosphatase antiserum; lack of inhibition by L-homoarginine; moderate inhibition by EDTA; and lack of interaction with wheat germ lectin. The enzyme was less sensitive than placental alkaline phosphatase to inhibition by L-phenylalanine, L-tryptophan, L-leucine, L-leucyl-glycyl-glycine and L-phenylalanyl-glycyl-glycine.