Cerebrospinal Fluid Lysophosphatidylcholine Species for Distinguishing Narrowing of the Lumbar Spine

Abstract

ContextReoperation, sometimes multiple, is common with progressively worse outcomes in patients with degenerative lumbar spine diseases. Lysophosphatidylcholine (LPC), a precursor of lysophosphatidic acid, in the cerebrospinal fluid (CSF) is a possible biomarker for neuropathic pain and discriminating neuropathic pain caused by lumbar spinal canal stenosis (LSCS) from other etiologies. This study aimed to explore this possible use of LPC species in the CSF. DesignUsing liquid chromatography-tandem mass spectrometry, we measured six LPC species, (16:0), (18:0), (18:1), (18:2), (20:4), and (22:6), in the CSF. Setting[Multi-site observational study] ParticipantsPatients with LSCS (n=137) and persistent spinal pain syndrome (PSPS, n=22). InterventionsCSF collection using lumbar puncture. Outcome MeasuresWe compared the LPC values between the groups and determined the cutoff levels that could efficiently discriminate the groups with high accuracy. ResultsThe levels of all measured LPC species were significantly higher in the LSCS group than the PSPS group. Four LPC species demonstrated more than 0.80 area under the curve obtained from the receiver operating characteristic curve analysis. Although the specificity of cutoff levels for the six LPC species was low to moderate, their sensitivity was consistently high. ConclusionThe existing diagnostic protocols combining physical examinations and morphological imaging studies for lumbar spinal pain have limited sensitivity. Measuring LPC species in the CSF is a promising objective laboratory test and could be suitable for detecting the presence of lumbar spinal stenosis and can help indications for surgery.