5-methyltetrahydrofolate and Cerebellar-Diseases

To describe the phenotype and the response to folinic acid supplementation of cerebral folate deficiency (CFD) in adults, a disorder diagnosed on low 5-methyltetrahydro-folate (5MTHF) in cerebrospinal fluid (CSF), which can correspond to a inherited disorder of folate metabolism (IDFM) or to a metabolic consequence of various neurological diseases.. We conducted a retrospective study on 224 adult patients with neurological symptoms who had a 5MTHF CSF dosage, collecting their neurologic and neuroimaging data.. 69 patients had CFD (CSF 5MTHF level < 41 nmol/L), 25 of them had severe CFD (sCFD; ≤25 nmol/L) with adult onset neurological symptoms in 41%. 56% of sCFD patients had an underlying identified neurologic disorder, mainly mitochondrial diseases, hepatic encephalopathy and primary brain calcifications (no identified IDFM), the others were classified as undiagnosed. sCFD patients presented most frequently pyramidal syndrome (75%), movement disorders (56%), cerebellar syndrome (50%) and intellectual disability (46%). MRI findings mostly showed white matter abnormalities (WMA; 32%) and calcifications (12%), and were normal in 23%. The clinico-radiological phenotype of sCFD patients was not clearly different from non CFD patients in terms of manifestations frequency. However, their neurological picture was more complex with a higher number of combined neurological symptoms (4.7±1.6 vs 3.4±1.7, p = .01). In Magnetic Resonance Spectroscopy (MRS), Choline/Creatine (Cho/Cr) ratio was lower in sCFD patients (n = 7) compared to non-CFD patients (n = 73) (p = .005), with good sensitivity (71%) and excellent specificity (92%). Among twenty-one CFD patients treated with folinic acid, nine had a sustained improvement, all with sCFD but one (50% of sCFD patients improved). In two undiagnosed patients with extremely low 5MTHF CSF values, MRI WMA and low Cho/Cr ratios, folinic acid treatment leaded to a dramatic clinical and radiological improvement.. CSF 5MTHF dosage should be considered in patients with mitochondrial diseases, primary brain calcifications and unexplained complex neurological disorders especially if associated with WMA, since folinic acid supplementation in patients with sCFD is frequently efficient.

Topics: Adolescent; Adult; Aged; Calcinosis; Cerebellar Diseases; Child; Child, Preschool; Female; Folic Acid; Folic Acid Deficiency; Follow-Up Studies; Humans; Infant; Infant, Newborn; Intellectual Disability; Magnetic Resonance Imaging; Male; Middle Aged; Mitochondrial Diseases; Mutation; Proteins; Retrospective Studies; Tetrahydrofolates; White Matter; Young Adult

Cerebral folate deficiency (CFD) may be underdiagnosed, as it manifests with various non-specific neurological symptoms. The diagnosis of CFD requires a determination of 5-methyltetrahydrofolate (5MTHF) in the cerebrospinal fluid (CSF), which is available in a limited number of specialized laboratories. In clinical biochemistry laboratories, total folate (TF) determination in serum or plasma is routinely performed by automated analyzers. The aim of this study is to determine whether the automated assay of CSF TF is a helpful screening tool for CFD.. We analyzed CSF samples collected from 73 pediatric patients. We measured CSF TF, serum TF, and CSF 5MTHF in 73, 70, and 48 patients, respectively. The assay of 5MTHF was conducted by a newly developed system utilizing liquid chromatography-tandem mass spectrometry (LC-MS/MS). We investigated the correlation between TF and 5MTHF in the CSF.. There was a strong positive correlation between CSF TF and 5MTHF (ρ=0.930, p<0.0001, n=48). Age was negatively correlated with CSF TF (ρ=-0.557, p<0.0001, n=51), serum TF (ρ=-0.457, p=0.0008, n=51), and CSF 5MTHF (ρ=-0.387, p=0.0263, n=33), but not with the CSF/serum TF ratio.. The automated assay of CSF TF is helpful to estimate CSF 5MTHF. The CSF TF assay may have a significant impact on the early diagnosis of CFD, because clinicians have better access to it than the 5MTHF assay.

Topics: Adolescent; Cerebellar Diseases; Child; Child, Preschool; Chromatography, High Pressure Liquid; Early Diagnosis; Folic Acid; Folic Acid Deficiency; Humans; Infant; Reference Values; Tandem Mass Spectrometry; Tetrahydrofolates