The amount of a phosphatidylinositol 5-phosphate 4-kinase type-2 beta when measured in blood serum. The trait is level of phosphatidylinositol 5-phosphate 4-kinase type-2 beta in blood serum (OBA_2042898, an Ontology of Biological Attributes identifier). Also known as: blood serum phosphatidylinositol 5-phosphate 4-kinase type-2 beta amount.