Cerebrospinal Fluid Total Protein Concentrations Research Articles

Time of Day Influences Concentrations of Total Protein and Albumin in Cerebrospinal Fluid in HIV.

The accumulation of soluble proteins and metabolites during wakefulness and their clearance during sleep via the glymphatic system occurs in healthy adults and is disturbed in some neurological conditions. Such diurnal variations in the cerebrospinal fluid (CSF) proteins produced outside the central nervous system and entering via the blood-brain barrier (BBB) have not been evaluated in people with HIV (PWH). CSF and blood were collected in 165 PWH at six US centers between 2003 and 2007. The time of collection was compared to CSF albumin, globulin, and total protein concentrations using bivariate and multivariate regression. Participants all took antiretroviral therapy (ART) and were mostly middle-aged (median age 44.0 years) men (78.8%), with AIDS (77.0%), plasma HIV RNA ≤ 200 copies/mL (75.8%), and immune recovery (median CD4+ T-cell count 414/µL). CSF was collected at median 1:10 p.m. (range 9:00 a.m. to 5:20 p.m.) and within a median of 15 min of blood collection. A later time of CSF collection was associated with higher total protein (p = 0.0077) and albumin (p = 0.057) in CSF but not in serum, and was additionally associated with higher CSF globulin (p = 0.013). The glymphatic clearance of albumin, globulin, and total protein is preserved in PWH. The analyses of soluble biomarkers in CSF should account for the time of collection.

Cerebrospinal fluid protein in Guillain-Barré syndrome: Need for age-dependent interpretation.

Background and purposeElevated cerebrospinal fluid (CSF) total protein in patients with acute ascending paresis is indicative of Guillain–Barré syndrome (GBS). Recent studies showed that the outdated, but still widely used upper reference limit (URL) for CSF total protein of 0.45 g/L leads to false‐positive results, mainly as a result of lack of age‐adjustment. The objective of this study was to assess the frequency of increased CSF total protein in adult GBS patients according to a new age‐dependent URL.MethodsPatients with GBS treated at the Medical University of Innsbruck between 2000 and 2018 were included in this study. Demographic, clinical, electrophysiological and CSF data were obtained from patients' medical charts. Frequency of increased CSF total protein depending on disease duration was compared using the conventional URL of 0.45 g/L and the age‐dependent URL.ResultsNinety‐seven patients with GBS aged 57 ± 18 years, comprising 38% women, underwent CSF sampling within a median of 6 days after symptom onset. The median CSF total protein concentration was 0.65 g/L and correlated with disease duration. Overall, 74% of patients had elevated CSF total protein levels using the conventional URL, as opposed to 52% applying the age‐dependent URL. At 0–3, 4–7, 8–14 and >14 days after disease onset, elevated CSF total protein was found in 46%, 84%, 78% and 100% of patients using the conventional URL, and in 32%, 53%, 65% and 64% of patients using the age‐dependent URL. In multivariate analysis, significant predictors of elevated CSF total protein were disease duration and the demyelinating GBS variant. Similar results were obtained for CSF/serum albumin quotient (Qalb).ConclusionFewer true‐positives for CSF total protein and Qalb must be considered in suspected GBS, especially in the early disease course.

Changes of cerebrospinal fluid protein concentrations and gait patterns in geriatric normal pressure hydrocephalus patients after ventriculoperitoneal shunting surgery

Normal pressure hydrocephalus (NPH) was the first type of dementia ever described that can be treated using ventriculoperitoneal shunting surgery. Three typical clinical symptoms of NPH include gait disturbance, progressive cognitive dysfunction, and urinary incontinence. Although there are articles that have discovered several cerebrospinal fluid (CSF) protein biomarkers associated with NPH; however, studies examining individual and total protein concentrations from the ventricular CSF before and after shunting surgery are lacking. This study used proteomics to calculate the CSF individual and total protein concentrations before, and one week, one month and three months after the shunting surgery. Parameters of cadence, step length, walking speed, and percentages of single- and double-limb support in a gait cycle were measured. Protein concentrations associated with anti-oxidation, aging, and in the prevention of neurotoxic agent production increased by at least 2-folds after the surgery, indicating that the brain may become less susceptible to neurodegeneration. These proteins were alpha-1B-glycoprotein, apolipoproteins A-1 & A-IV, prostaglandin-H2 D-isomerase, alpha-1-antitrypsin, and serotransferrin. In gait analysis, lower cadence, decreased double-limb support, longer step length, and increased single-limb support were observed after the surgery, indicating a more stable walking balance. These changes lasted for a period of at least 3 months. As a result, shunting surgery may be recommended for geriatric patients with confirmed diagnosis of normal pressure hydrocephalus.

Cerebrospinal fluid:serum glucose ratio in the ventricular and lumbar compartments: implications for clinical practice.

Calculation of the cerebrospinal fluid:serum glucose (CSF:SGlu ) ratio is part of the routine cerebrospinal fluid (CSF) work-up. Reference values have been defined for lumbar CSF, but are lacking for ventricular CSF. The objective of this study was to investigate whether the CSF:SGlu ratio is similar in lumbar and ventricular compartments, and to determine cut-off values for CSF:SGlu ratio in ventricular CSF. We included CSF samples that were collected by either lumbar puncture or ventricular drainage, with a red blood cell count <500/μL, normal white blood cell count and age-related normal total protein content, with simultaneously withdrawn serum sample and time to laboratory processing of ≤2 h. This resulted in 1808 sample pairs. Glucose concentrations in CSF and serum were measured by enzymatic spectrophotometry. The CSF:SGlu ratio was similar in ventricular and lumbar compartments after controlling for age, sex, time between sample withdrawal and laboratory processing, CSF white blood cell and red blood cell count, CSF total protein and serum glucose concentration using a multiple linear regression model. Lower limits for CSF:SGlu ratio in the ventricular compartment, defined as 5th percentile, were 0.51 for patients with serum glucose concentration < 100 mg/dL, 0.45 for those with serum glucose concentration ≥ 100 mg/dL and <150 mg/dL, and 0.36 for those with serum glucose concentration ≥150 mg/dL. The CSF:SGlu ratio was similar in the ventricular and lumbar compartments, and depended mainly on time to laboratory processing and absolute serum glucose levels. Previously established lower limits for CSF:SGlu ratio in lumbar CSF can be also applied for ventricular CSF.

Reaction of complement factors and proteasomes in experimental encephalitis

Herpes simplex virus type 1 (HSV-1) encephalitis causes a deleterious inflammation and elevated intracranial pressure. As a step towards examining the origin of the inflammation, we here report the response of circulating proteasomes and complement factors in blood and cerebrospinal fluid (CSF) in rats infected with HSV-1. Infection was via the nasal route, with 1.1 × 104 plaque-forming units of HSV-1 strain 2762 given in one or both nostrils. A sandwich enzyme-linked immunosorbent assay was used to study the level of 26S proteasomes and their complex formation with complement factors 3 and 4. HSV-1 infection in the rat causes a complex formation between complement factors and proteasomes, which we designate compleasomes. In the first experiment, with HSV-1 given in both nostrils, compleasomes containing complement factors 3 and 4 increased significantly in both blood plasma and CSF. The concentration of proteasomes in plasma was similar in controls and infected rats (320 ± 163 vs. 333 ± 125 ng/ml). In the second experiment, with HSV-1 given in one nostril, CSF levels were 1 ± 1 ng/ml in controls and 56 ± 22 ng/ml in the HSV-1 group, whereas the total protein concentration in CSF remained the same in the two groups. The compleasome response was limited to CSF, with a highly significant difference between infected rats and controls (n = 11, p < 0.001). It was possible to mimic the reaction between proteasomes and complements 3 and 4 in vitro in the presence of ATP.

An update of the Mayo Clinic cohort of patients with adult primary central nervous system vasculitis: description of 163 patients.

Primary central nervous system vasculitis (PCNSV) is an uncommon condition in which lesions are limited to vessels of the brain and spinal cord. Because the clinical manifestations are not specific, the diagnosis is often difficult, and permanent disability and death are frequent outcomes. This study is based on a cohort of 163 consecutive patients with PCNSV who were examined at the Mayo Clinic over a 29-year period from 1983 to 2011. The aim of the study was to define the characteristics of these patients, which represents the largest series in adults reported to date. A total of 105 patients were diagnosed by angiographic findings and 58 by biopsy results. The patients diagnosed by biopsy more frequently had at presentation cognitive dysfunction, greater cerebrospinal fluid total protein concentrations, less frequent cerebral infarcts, and more frequent leptomeningeal gadolinium-enhanced lesions on magnetic resonance imaging (MRI), along with less mortality and disability at last follow-up. The patients diagnosed by angiograms more frequently had at presentation hemiparesis or a persistent neurologic deficit or stroke, more frequent infarcts on MRI and an increased mortality. These differences were mainly related to the different size of the vessels involved in the 2 groups. Although most patients responded to therapy with glucocorticoids alone or in conjunction with cyclophosphamide and tended to improve during the follow-up period, an overall increased mortality rate was observed. Relapses occurred in one-quarter of the patients and were less frequent in patients treated with prednisone and cyclophosphamide compared with those treated with prednisone alone. The mortality rate and degree of disability at last follow-up were greater in those with increasing age, cerebral infarctions on MRI, angiographic large vessel involvement, and diagnosis made by angiography alone, but were lower in those with gadolinium-enhanced lesions on MRI and in those with cerebral amyloid angiopathy. The annual incidence rate of PCNSV was estimated at 2.4 cases per 1,000,000 person-years. PCNSV appears to consist of several subsets defined by the size of the vessels involved, the clinical characteristics at presentation, MRI findings, and histopathological patterns on biopsy. Early recognition and treatment may reduce poor outcomes.

Urinary trypsin inhibitor levels are reduced in cerebrospinal fluid of multiple sclerosis and neuromyelitis optica patients during relapse

BackgroundNeutrophil-mediated inflammation plays an important role in the pathogenesis of multiple sclerosis (MS) and neuromyelitis optica (NMO). Concentrations of urinary trypsin inhibitor (UTI) have attracted attention as a useful index of the status of inflammatory response. Evidence suggests serum UTI levels are increased in some inflammatory diseases, but little attention has been paid to cerebrospinal fluid (CSF) levels of UTI. ObjectiveTo measure CSF concentration of UTI and determine its relationship with disease activity in MS and NMO. MethodsCSF UTI was measured by an enzyme-linked immunosorbent assay in 18 MS patients, 28 NMO patients and eight controls. ResultsCSF UTI concentrations in MS and NMO groups were both significantly lower than those in controls. Expanded disability status scale scores of MS and NMO revealed a trend of increased disease disability with decreased CSF UTI level. The CSF UTI concentrations were not significantly associated with CSF white blood cell counts, total protein, glucose and chlorine concentrations in MS and NMO subgroups. ConclusionsOur results indicate a reduced UTI level in CSF of MS and NMO patients. The levels were associated with the severity of the two demyelinating diseases during relapse.

Tumor necrosis factor-α and interleukin-6 concentrations in cerebrospinal fluid of dogs after seizures.

BackgroundIdiopathic and acquired epilepsy are common in dogs. Up to 30% of these dogs are refractory to pharmacological treatment. Accumulating experimental evidence indicates that brain immune response and presence of inflammatory mediators decrease the threshold for individual seizures and contribute to epileptogenesis.HypothesisDogs with seizures have higher cerebrospinal interleukin‐6 (IL‐6) and tumor necrosis factor‐α (TNF‐α) concentrations compared to dogs with no seizures.MethodsA prospective double blinded study; cerebrospinal fluid (CSF) and serum IL‐6, TNF‐α and total protein (TP) concentrations were measured by a blinded investigator for the study group and CSF IL‐6 and TNF‐α levels and TP concentrations were measured in the control group (CG).AnimalsDogs presented with seizures that had enough CSF collected to allow analysis were included in the study group. Twelve apparently healthy, quarantined, stray dogs served as control (CG).ResultsCerebrospinal fluid TNF‐α and IL‐6 concentrations were significantly higher (P = .011, P = .039) in dogs with seizures (0 ± 70.66, 0.65 ± 10.93 pg/mL) compared to the CG (0 ± 19, 0.73 ± 0.55 pg/mL). When assessing cytokine concentrations of specifically the idiopathic epilepsy (IE) dogs compared to the CG, only TNF‐α concentrations (8.66 ± 62, 0 ± 19 pg/mL) were significantly higher (P = .01). CSF TP concentrations were not significantly higher in the study dogs compared to the CG.Conclusions and Clinical ImportanceHigher TNF‐α and IL‐6 concentration in the CSF of dogs with naturally occurring seizures. The higher supports the hypothesis that inflammatory processes through certain mediators play a role in the pathogenesis of seizures in dogs.

Specificity of elevated cerebrospinal fluid bilirubin in the investigation of subarachnoid haemorrhage.

The spectrophotometric examination of cerebrospinal fluid for bilirubin is an established investigation in patients with suspected subarachnoid haemorrhage. This study assesses the diagnostic specificity of an elevated cerebrospinal fluid bilirubin and how this may be influenced by the presence of oxyhaemoglobin and the concentration of cerebrospinal fluid total protein. One thousand cerebrospinal fluid spectroscopy reports were reviewed. Electronic patient records were examined to determine the clinical outcome in patients with an elevated cerebrospinal fluid bilirubin. Forty-four out of 1000 cerebrospinal fluid scans showed an increase in cerebrospinal fluid bilirubin unrelated to elevated serum bilirubin concentrations. This was associated with subarachnoid haemorrhage in 16 (36%) cases. Subarachnoid haemorrhage was confirmed in 5/17 (29%) patients positive for cerebrospinal fluid bilirubin alone and in 11/27 (41%) patients positive for both cerebrospinal fluid bilirubin and oxyhaemoglobin. At cerebrospinal fluid total protein concentrations <1 g/L, the specificity for subarachnoid haemorrhage improved: 4/9 (44%) vs. 1/8 (13%) with an increase in cerebrospinal fluid bilirubin alone; 6/10 (60%) vs. 5/17 (29%) in patients with increases in both bilirubin and oxyhaemoglobin. While an increase in cerebrospinal fluid bilirubin may be considered consistent with subarachnoid haemorrhage, the likelihood that a subarachnoid haemorrhage has occurred is influenced by the presence of oxyhaemoglobin and the concentration of total protein in the cerebrospinal fluid.

Cerebrospinal fluid total protein cannot reliably distinguish true subarachnoid haemorrhage from other causes of raised cerebrospinal fluid net bilirubin and net oxyhaemoglobin absorbances.

In cerebrospinal fluid (CSF) spectrophotometry, if the net bilirubin absorbance (NBA) and net oxyhaemoglobin absorbance (NOA) are both raised with a visible oxyhaemoglobin peak, the revised national guidelines for analysis of CSF bilirubin advise interpreting the results as 'Consistent with subarachnoid haemorrhage (SAH)' regardless of the CSF total protein concentration of the specimen. We wanted to study the range of CSF total protein concentrations found in confirmed SAH to establish if the CSF total protein value can give further guidance on the likelihood of SAH. Consecutive cases from five different hospital sites were included if the CSF NBA was greater than 0.007 AU and the NOA was greater than 0.02 AU with a visible oxyhaemoglobin peak. For the cases identified, the laboratory information management system and patient records were interrogated to identify the total protein concentration of the CSF specimen and whether SAH had ultimately been confirmed or excluded by other methods and supporting evidence. Results from 132 patients were included. The CSF total protein range in confirmed SAH was 0.23-3.08 g/L with a median concentration of 0.7 g/L (n = 51). In the SAH excluded group, the CSF total protein range was 0.43-29 g/L with a median concentration of 1.9 g/L (n = 81). Although confirmed SAH was not associated with the very highest concentrations of CSF total protein, a definite CSF protein cut-off concentration above which SAH could reliably be excluded cannot be recommended.

Increased interleukin-17 in the cerebrospinal fluid in sporadic Creutzfeldt-Jakob disease: a case-control study of rapidly progressive dementia

BackgroundInflammatory responses in the cerebrospinal fluid (CSF) of patients with sporadic Creutzfeldt-Jakob disease (sCJD) remain elusive.MethodsWe conducted a case-control study, in which 14 patients with sCJD, 14 with noninflammatory neurological disorders, and 14 with autoimmune encephalitis were enrolled. We used the suspension array system to measure the concentrations of 27 cytokines in CSF. The cytokine titers of the three groups were compared, and the correlation between the relevant cytokine titers and clinical parameters was investigated in the patients with sCJD.ResultsLevels of the two cytokines interleukin (IL)-1 receptor antagonist and IL-17 were significantly elevated in the patients with sCJD compared with those in the patients with noninflammatory neurological disorders: IL-17 levels in sCJD were approximately ten times higher than in the noninflammatory neurological disorders (mean, 35.46 vs. 3.45 pg/ml; P < 0.001) but comparable to that in encephalitis (mean, 32.16 pg/ml). In contrast, levels of classical proinflammatory cytokines such as IL-12(p70) and tumor necrosis factor-α were increased only in encephalitis. Although not significant, IL-17 titers tended to be higher in the patients with shorter disease duration before CSF sampling (r = -0.452; P = 0.104) and in those with lower CSF total protein concentrations (r = -0.473; P = 0.086).ConclusionsIL-17 is significantly increased in CSF in sCJD, which can be an early event in the pathogenesis of sCJD.

Quantitative Analysis of Cerebrospinal Fluid Brain Derived Neurotrophic Factor in the Patients with Multiple Sclerosis

Multiple sclerosis (MS) is the most common cause ofnontraumatic neurological disability in Europe and North America. Growth factor expression could participate in the repair process of the demyelinating disease. Among growth factors, brain derived neurotrophic factors (BDNF) has been demonstrated to play an important role in neuronal and axonal survival. In the central nervous system (CNS), neurons are the main source of BDNF. Another potential source are activated astrocytes, which are present in inflamed areas in the CNS as shown in MS. In this study, total protein concentration (TPC) and BDNF levels in the cerebrospinal fluid (CSF) samples from the patients with MS (n = 48) and control subjects (n = 53) were measured using a Bio-Rad protein assay and enzyme linked immunosorbent assay (ELISA). No significant change in the CSF TPC of patients with MS was seen as compared to normal CSF. The presence of BDNF in the CSF samples was shown by Western blot. Using ELISA, it was shown that the level of BDNF in the MS CSF is higher than in normal CSF. It is concluded that BDNF is a constant component of human CSF. Moreover, it could be implicated in the pathophysiology of MS.

Blood–brain‐barrier disruption in chronic canine hypothyroidism

Central nervous system (CNS) manifestations of hypothyroidism have been associated with cerebrovascular complications. Reports of cerebrospinal fluid (CSF) abnormalities are rare in hypothyroid dogs. The aim of this study was to determine if chronic hypothyroidism causes blood-brain-barrier (BBB) abnormalities that are detectable using indirect CSF biomarkers. The study included 18 normal, euthyroid, female mixed-breed dogs. Hypothyroidism was induced by (131) iodine administration in 9 dogs; 9 served as untreated controls. Evaluations included physical and neurologic examination, complete CSF analysis, serum and CSF protein electrophoresis, measurement of plasma vascular endothelial growth factor (VEGF) and serum S-100B concentrations, and calculation of CSF albumin quota (AQ) and were conducted at baseline and 6, 12, and 18 months after induction of hypothyroidism. Data were analyzed using repeated measures ANOVA. At baseline, differences between groups were not detected for any variable. Throughout the study, controls dogs remained free of neurologic disease and had test variables that remained within reference intervals. Two hypothyroid dogs developed CNS signs during the study, and evidence of cerebrovascular disease was found at necropsy. At 12 and 18 months, the CSF total protein, VEGF, S-100B, and fractional albumin concentrations, and AQ were significantly higher (P<.04) in hypothyroid dogs than controls. Among test variables assayed in serum or plasma, the only significant difference was a higher S-100B concentration in hypothyroid dogs (P=.003) at 18 months. BBB integrity is disrupted in chronic hypothyroidism. Significant increases in CSF concentrations of VEGF and S100-B in hypothyroid dogs indicate dysfunction in both endothelial and glial elements of the BBB.

Selenium Concentration in Cerebrospinal Fluid Samples from a Paediatric Population

Selenium is an important trace element for brain function. Our objective was to analyse cerebrospinal fluid (CSF) selenium (Se) in 89 paediatric patients. We also studied correlations between Se and other biochemical variables (age, CSF protein concentrations and glutathione peroxidase activity and plasma Se values). Cerebrospinal fluid Se values showed a significant negative correlation with the age of patients (r = -0.476; p < 0.0001), and positive with CSF total protein concentrations and GPX activity (r = 0.446, p < 0.001; r = 0.431; p = 0.001, respectively). No association was observed between plasma and CSF Se concentrations. Median CSF Se values were 32 times lower when compared with those for plasma. In conclusion, CSF Se concentrations depend on age and total CSF protein values. The association observed between CSF Se and GPX activity suggests that Se quantification might be a reflection of some Se-dependent protein function. Cerebrospinal fluid Se values were independent of serum Se concentrations.

Heparin interference in the cerebrospinal fluid protein assay measured with a pyrogallol red–molybdate complex

Background Increased cerebrospinal fluid (CSF) total protein is a useful indicator of meningeal or central nervous system disease. Occasionally the primary care physicians added heparin to CSF samples to avoid clotting. The aim of this study is to investigate the interference of heparin on CSF total protein measurement. Methods CSF specimens were collected from 230 in-patients with various diseases and analyzed by the Vitros 950 PROT slide and the Toshiba TBA-120FR assay. After adding 0, 0.0625, 0.25, 0.5, 0.75, 1, 2 and 4 IU/ml of heparin that was diluted in 20 µl of normal saline to 180 µl of CSF aliquots, CSF total protein concentrations were determined again by the 2 assay systems in the absence or presence of protamine. Results At low (< 40 mg/dl) and mildly increased (40–< 100 mg/dl) CSF total protein, the measured protein concentrations significantly decreased up to 91% when 4 IU/ml of heparin was added to the samples before being analyzed by the Toshiba TBA-120FR assay. At moderately increased (100–< 200 mg/dl) and high (≥ 200 mg/dl) CSF total protein, 62% and 27% decreases were found, respectively. Only 1–8% decline was found when 4 IU/ml of heparin was added to the samples before being analyzed by the Vitros 950 PROT assay. Addition of protamine partially reversed the interference of heparin. Conclusions The interference of heparin in the CSF total protein assay is dependent on the reaction principle, especially when the CSF total protein level is normal to mildly elevated.

Strong interference of hemoglobin concentration on CSF total protein measurement using the trichloroacetic acid precipitation method

Among other methods, trichloroacetic acid precipitation is used to quantify total protein in cerebrospinal fluid (CSF). We analyzed the influence of hemoglobin on total protein concentration assayed by the trichloroacetic acid method and compared the results to the benzethonium chloride method. Four CSF samples were spiked with different amounts of hemoglobin, leading to overestimation of protein concentration when assayed by the trichloroacetic acid method. Using the benzethonium chloride method, measurement of protein concentration was minimally disturbed. In addition, albumin and total protein concentrations were measured in 135 clinical samples. The total protein/albumin ratio remained constant when protein was measured with the benzethonium chloride method, while ratios increased when protein was assayed by the trichloroacetic acid method. Strong interference by hemoglobin leads to overestimation of the total protein concentration in CSF when assayed by the trichloroacetic acid method and may lead to false conclusions when evaluating the blood-brain barrier.

HYALURONAN IN THE CEREBROSPINAL FLUID OF PATIENTS WITH SPINAL TUMOR

The clinical significance of hyaluronan (HA) levels in the cerebrospinal fluid (CSF) of patients with spinal tumor (ST) was evaluated in order to clarify whether HA concentrations in the CSF of patients with ST differ according to such factors as the tumor site and histopathological diagnosis. CSF samples were obtained from 40 patients with ST who had undergone myelography and CSF examinations retrospectively. The HA levels were determined using a sandwich-binding protein assay. The total protein (TP) levels were also determined. The HA and TP concentrations in CSF were significantly higher in patients with extramedullary tumor than in patients with intramedullary tumor. There was a significant correlation between HA and TP concentrations in CSF patients with ST. A HA assay for CSF is therefore considered to be potentially useful for estimating the localization of ST.

Clinical characteristics of multiple sclerosis in Taiwan: a cross-sectional study

This study reviewed the clinical characteristics of multiple sclerosis (MS) in Taiwanese patients from 1993 to 2001. Of the 75 MS patients with a mean age of onset of 35.6±12.6 years, the female-to-male ratio was 4.4 (61/14). In 42 (56%) optico-spinal MS (OS-MS) patients, the age of onset (37.6±11.1 years) tended to be older than conventional MS (C-MS) patients (33.1±14.1 years, P = 0.08). In 60 cerebrospinal fluid (CSF) specimens, raised IgG index (>0.7) and oligoclonal bands were noted in 26 (43.3%) and two (3.3%) cases, respectively. The frequency of raised IgG index was lower in OSMS (31.3%) than in C-MS (57.1%, P = 0.07). The CSF total protein concentrations were significantly higher in OS-MS (64.5 mg/dL) than in C-MS (46.6 mg/dL, P = 0.047). The mean annual relapse rate was 54.1%, and was significantly higher within the first year (59.7%, P<0.001). The mean annual relapse rate in OS-MS (62.7%) was significantly higher than in C-MS (41.2%, P = 0.01). The differences in the annual relapse rate and total protein concentration in CSF between OS-MS and C-MS suggest probably two distinct immunopathogenesis. The higher first year relapse rate of MS patients in Taiwan may address the importance of early intervention with immunomodulatory therapy.

High Resolution Protein Electrophoresis of 100 Paired Canine Cerebrospinal Fluid and Serum

This study was performed to investigate the diagnostic relevance of cerebrospinal fluid (CSF) high resolution electrophoresis. The laboratory technique was applied to 100 paired samples of canine CSF and serum, with paired samples tested during the same analytical run, as recommended in human medicine. Ninety four of the dogs had a neurological disease and 6 healthy dogs served as a control group. A strong linear correlation between CSF total protein concentration and the albumin quota (AQ) was found in the control group and in the inflammatory (infectious or noninfectious), neoplastic, and miscellaneous groups: AQ = 0.015 CSF total protein ‐ 0.102, r= 0.990. This correlation suggests that an increased CSF total protein concentration can be an indicator of blood brain barrier dysfunction. The highest median AQ value was found in the aseptic suppurative meningitis group, but no statistical differences were found between this and the other groups. The AQ, calculated with this technique, did not provide any additional information. Moreover, although unexpected, the electrophoretic profiles were not characteristic of any particular disease. In conclusion, this study did not confirm high resolution electrophoresis of paired CSF and serum samples to be a valuable ancillary diagnostic tool for canine neurological diseases.

Determination of 5-methyltetrahydrofolate in cerebrospinal fluid of paediatric patients: Reference values for a paediatric population

Background Cerebral folate deficiency (CFD) has been described as a neurological syndrome associated with low 5-methyltetrahydrofolate (5-MTHF) values in cerebrospinal fluid (CSF) with normal folate concentrations in plasma. Our aim was to analyse CSF 5-MTHF concentrations in a paediatric control population and in patients with various neurological disorders. Methods We studied plasma and CSF samples from 63 paediatric controls (age range: 2 days to 18 years, average: 3.8 years) and from 165 patients (age range: 1 day to 22 years, average: 5.0 years) with severe epileptic encephalopathies of unknown origin, movement disorders, Rett syndrome and mitochondrial diseases. CSF 5-methyltetrahydrofolate was analysed by reverse phase HPLC with fluorescence detection (excitation: 295 nm and emission: 355 nm). Result A negative correlation between 5-MTHF values and age of controls was observed ( r = − 0.468; p < 0.0001) and reference values were therefore stratified into 3 age groups. Regarding patients, 122 out of 165 showed normal CSF 5-MTHF values while 43 showed decreased values ranging from profound to mild deficiencies. Increased CSF total protein values were associated with the presence of low 5-MTHF concentrations ( χ 2 = 7.796; p = 0.005). Conclusions The application of this method has been useful for the establishment of reference values and for diagnosis of CFD in paediatric patients. Furthermore, increased CSF total protein concentrations should be considered as a marker of a possible CFD.