The amount of a heterogeneous nuclear ribonucleoprotein K (human) when measured in cerebrospinal fluid. The trait is level of heterogeneous nuclear ribonucleoprotein K (human) in cerebrospinal fluid (OBA_2058295, an Ontology of Biological Attributes identifier). Also known as: cerebrospinal fluid heterogeneous nuclear ribonucleoprotein K (human) amount.