Cerebrospinal fluid and serum concentrations of beta‐trace protein during pregnancy

Abstract

SummaryWe conducted a prospective observational study among a cohort of 40 term parturients undergoing spinal anaesthesia for elective Caesarean section, to determine the concentration of b-trace protein in cerebrospinal fluid (CSF) and serum. Serum and CSF samples, taken at the time of dural puncture, were assayed by nephelometry. The mean serum b-trace protein concentration was 0.39 mg.l )1 and the mean CSF concentration was 27.9 mg.l )1 , giving a mean ratio of CSF to serum concentration of 76. This ratio is higher than that published for non-pregnant females and for males because of both a higher mean CSF and a lower mean serum b-trace protein concentration. The concentration correlated positively with both serum creatinine and gestational age. If these concentrations are used to estimate the normal range, we propose that the nephelometric measurement of b-trace protein might prove a useful diagnostic test for cerebrospinal fluidcutaneous fistula in parturients. Reports of cerebrospinal fluid-cutaneous fistulae (CSFCF) complicating epidural anaesthesia are uncommon [1]. However, in our experience, fluid leakage at the site of epidural needle insertion for combined spinal-epidural anaesthesia is not uncommon [2]. A fast and accurate test to detect CSF in such fluid would be valuable, given concern that meningitis might complicate the clinical picture [3]. The nephelometric assay of b-trace protein is considered the best method of detecting CSF rhinorrhoea and otorrhoea [4], and concentrations of serum and CSF b-trace protein have been determined for healthy male and female patients. However, the CSF concentration of b-trace protein has not been studied in the pregnant population. b-trace protein (prostaglandin D synthase) is an abundant brain-specific protein, comprising about 3% of the total CSF protein [5]. It is synthesised by both the choroid plexus and the leptomeninges [4], and is normally found in CSF in concentrations 35 times higher than in serum. This ratio is the highest of all the CSF-specific proteins, making b-trace protein an ideal marker for the detection of CSF [6,7].

CSF prostaglandin D synthase is reduced in excessive daytime sleepiness

“…The discrepancy between our finding of low CSF L-PGDS levels (which has been replicated in repeated measurements) and the recent report of increased serum levels in narcoleptic patients cannot be explained yet [11]. The finding of discrepant serum and CSF L-PGDS concentrations was recently found to be useful to detect CSF leaks [12]. Similarly, earlier reports found that CSF L-PGDS levels can be used in conjunction with CSF/serum albumin ratio to distinguish between different neurological pathologies associated with CSF protein increase and blood-brain barrier dysfunctions [13].…”

Expression of lipocalin-type prostaglandin D synthase in preeclampsia patients: a novel marker for preeclampsia

“…16,18 -20) L-PGDS/ β-trace is also abundant in various types of biological fluids such as cerebrospinal fluid, ascites, seminal plasma, and amniotic fluid. [21][22][23][24][25][26] Although the biological role of this enzyme or its prostanoid product remains unclear, several studies have shown L-PGDS to be increased in patients with renal insufficiency, 13,27,28) diabetes mellitus, 29,30) hypertension, 31) angina 32) and osteoarthritis. 33) In addition, Taba et al 34) showed that laminar shear stress loading onto endothelial cells caused increased expression of mRNA for L-PGDS.…”

CSF proteomic analysis reveals persistent iron deficiency‐induced alterations in non‐human primate infants

“…Prostaglandin D synthase (PGD synthase) is an abundant brain‐specific protein and is used as a marker of CSF during fetal development (McArthur et al. 2005).…”