Testing for Antiphospholipid Antibody (aPL) Specificities in Retrospective ?Normal? Cerebral Spinal Fluid (CSF)

摘要

Antiphospholipid antibodies (aPL) have been found in the blood of patients with systemic andneurological disease. The rare reports of aPL in cerebral spinal fluid (CSF) have been limited mostly toIgG and IgM anticardiolipin (aCL). Our published finding of IgA aPE in the CSF of a young strokevictim prompted us to establish “normal” CSF aPL values for a panel of aPL, which included aCL,antiphosphatidylserine (aPS), antiphosphatidylethanolamine (aPE) and antiphosphatidylcholine (aPC).CSF samples were tested by ELISA for IgG, IgM and IgA aPL. In addition, the CSF samples weretested for activity in the presence and absence of phospholipid (PL) binding plasma-proteins. A total of24 data points were obtained for each CSF sample.We tested 59 CSF samples obtained from 59 patientswho were undergoing evaluation for systemic or neurologic diseases. All CSF samples had normalprotein, glucose and cell counts. Ten of the 59 CSF samples (17%) had elevated aPL optical density(OD) values an order of magnitude higher than the other 49 CSF samples for one or more aPLspecificity and/or isotype. One CSF sample had both PL-binding protein dependent and independentIgG aPE activity. Another CSF sample showed both IgG aPE and aPC reactivity. The remaining eightCSF samples showed single aPL findings; IgG aPE (5), IgG aPC (1), IgG aCL (1) and IgM aPC (1).Seven of 10 patients with elevated CSF values were females. As expected, most “normal” aPL ODvalues were substantially lower in CSF than those we have reported in blood samples from volunteerblood donors.