Vasilios C. Constantinides

Cerebrospinal Fluid TAR DNA-Binding Protein 43 Combined with Tau Proteins as a Candidate Biomarker for Amyotrophic Lateral Sclerosis and Frontotemporal Dementia Spectrum Disorders

Background: Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are nowadays recognized as spectrum disorders with a molecular link, the TAR DNA-binding protein 43 (TDP-43), rendering it a surrogate biomarker for these disorders. Methods: We measured cerebrospinal fluid (CSF) levels of TDP-43, beta-amyloid peptide with 42 amino acids (Aβ42), total tau protein (τT), and tau protein phosphorylated at threonine 181 (τP-181) in 32 patients with ALS, 51 patients with FTD, and 17 healthy controls. Double-sandwich commercial enzyme-linked immunosorbent assays were used for measurements. Results: Both ALS and FTD patients presented with higher TDP-43 and τT levels compared to the control group. The combination of biomarkers in the form of the TDP-43 × τT / τP-181 formula achieved the best discrimination between ALS or FTD and controls, with sensitivities and specificities >0.8. Conclusion: Combined analysis of TDP-43, τT, and τP-181 in CSF may be useful for the antemortem diagnosis of ALS and FTD.

CSF biomarkers β-amyloid, tau proteins and a-synuclein in the differential diagnosis of Parkinson-plus syndromes

INTRODUCTION Differential diagnosis of Parkinson-plus patients (PSP, CBD, MSA) and Parkinsons disease (PD) patients is often not straightforward, particularly in atypical cases or at the initial stages of the diseases. Classic CSF biomarkers (amyloid-beta - Aβ42, tau protein - τT and phosphorylated tau protein - τP-181) are established biomarkers in the diagnosis of Alzheimers disease (AD). CSF a-synuclein (α-syn) has emerged as a promising biomarker in patients with Parkinsonism. The aim of this study was to analyze the CSF biochemical profile of patients with Parkinsonism. METHODS We analyzed the CSF biomarker profile (Aβ42, τT, τP-181, α-syn) and all relevant ratios in 68 patients with Parkinsonism (19 PSP, 15 MSA, 17 CBD, 17 PD) and 18 controls, diagnosed by latest established diagnostic criteria. RESULTS CBD patients exhibited elevated τT and decreased Aβ42 compared to the other groups. Five CBD, one PSP patient and one control had a typical AD CSF profile. After exclusion of these patients, the τT/Aβ42 ratio was significantly elevated in MSA patients compared to PD patients and provided excellent specificity and adequate sensitivity in their differential diagnosis. CONCLUSION CSF biochemical profile analysis is important in distinguishing AD patients with a CBS phenotype from non-AD CBS patients. The τT/Aβ42 ratio is useful in the differential diagnosis of MSA from PD.

Migraine and tension-type headache triggers in a Greek population

Migraine and tension type headache are the two most common primary headaches. The purpose of this study was to detect differences in clinical characteristics and headache triggers and in a Greek cohort of 51 migraineurs and 12 patients with tension-type headache. (TTH) Migraine patients had a significantly lower age at headache onset and frequency, higher mean visual analogue scale (VAS) and greater maximum duration of headache episodes compared to TTH patients. They did not differ from (TTH) patients in quality of headache, laterality of pain, way of headache installation and progression and temporal pattern of headaches. Nausea, vomiting and phonophobia were more frequent in migraine. Triggering of headaches by dietary factors was associated with migraine, whereas there was no difference between the two groups in any of the other headache triggers. Stress, both physical and psychological, were particularly common in both patient groups.

Simple linear brainstem MRI measurements in the differential diagnosis of progressive supranuclear palsy from the parkinsonian variant of multiple system atrophy

Differential diagnosis of progressive supranuclear palsy (PSP) and the parkinsonian variant of multiple system atrophy (MSA-P) from Parkinson’s disease (PD) can be difficult, particularly in atypical cases or early in the disease course. The Magnetic Resonance Parkinsonism Index (MRPI) utilizes linear and surface (planimetry) measurements and has been proposed as a dual MRI biomarker, with high values indicative of PSP and low values of MSA. The aim of this study was to examine the utility of simple linear MRI brainstem measurements, without the use of MRI planimetry, in the diagnosis of patients with Parkinsonism and compare them to the MRPI. A total of 51 patients (PSP: 24, MSA-P: 9, PD: 18) and 15 healthy controls were included. Simple linear MRI distances of brainstem structures were measured. These included midbrain and pons diameters as well as superior cerebellar peduncle (SCP) and middle cerebellar peduncle (MCP) widths. All relevant indices, including ratios and products, were also calculated. The SCP by midbrain product (SCP × midbrain) provided improved sensitivity (100 vs. 91%) and identical specificity (98%) for the diagnosis of PSP, compared to the MRPI. Neither the MRPI nor any of the linear measurements were able to discriminate MSA-P from PD. The SCP by midbrain product is a novel, potent MRI biomarker for PSP.

Anti-NMDA receptor encephalitis presenting as isolated aphasia in an adult

ABSTRACT Anti-NMDA receptor (NMDA-r) encephalitis is a relatively rare cause of autoimmune encephalitis with divergent clinical presentations. We report a case of an adult patient with anti-NMDA-r encephalitis presenting with isolated, abrupt-onset aphasia. Her condition remained unaltered over a period of 6 months. The patients’ electroencephalogram findings were typical for NMDA-r encephalitis; however, her magnetic resonance imaging and cerebrospinal fluid analysis were normal. She responded well to immunotherapy, and aphasia eventually resolved. The natural course of the present case contradicts the rapidly progressive nature of typical NMDA-r encephalitis. Furthermore, it broadens the clinical spectrum of anti-NMDA-r encephalitis, to incorporate isolated, nonprogressive aphasia.

Recognition of Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) in Two Oligosymptomatic Sisters with Low CADASIL Scale Scores and a Venous Dysplasia: Report of a Novel Greek Family

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) due to mutations of the NOTCH3 gene is the most common cause of inherited cerebral small-vessel disease and one of the genetic causes of migraine with aura. The so-called CADASIL scale has been proposed as a clinical screening tool, and a score of 15 or higher seems useful in identifying patients with high probability of carrying NOTCH3 mutations. We studied a novel Greek family with clinical features compatible with CADASIL. Genetic analysis of NOTCH3 in the 2 living patients revealed the R182C mutation. Both patients had low scores (12 and 14) in the CADASIL scale, probably due to their relatively young age (38 and 37 years, respectively) at which cognitive decline and external capsule involvement have not developed yet. Another unusual feature in the second patient was a venous dysplasia in the parietal lobe. Observations presented here add to the notion that the CADASIL scale, although useful, probably needs a revision, taking into account the patients age at which the score is calculated.

MRI Planimetry and Magnetic Resonance Parkinsonism Index in the Differential Diagnosis of Patients with Parkinsonism

BACKGROUND AND PURPOSE: Differential diagnosis of multiple system atrophy, progressive supranuclear palsy, and corticobasal degeneration from Parkinson disease on clinical grounds is often difficult. MR imaging biomarkers could assist in a more accurate diagnosis. We examined the utility of MR imaging surface measurements (MR imaging planimetry) in the differential diagnosis of patients with parkinsonism. MATERIALS AND METHODS: Fifty-two patients with Parkinson-plus (progressive supranuclear palsy, n = 24; corticobasal degeneration, n = 9; multiple system atrophy, n = 19), 18 patients with Parkinson disease, and 15 healthy controls were included. Corpus callosum, midbrain, and pons surfaces; relevant indices; and the Magnetic Resonance Parkinsonism Index were calculated. Corpus callosum subsection analysis was performed, and the corpus callosum posteroanterior gradient was introduced. RESULTS: A Magnetic Resonance Parkinsonism Index value of >12.6 discriminated progressive supranuclear palsy from other causes of parkinsonism with a 91% sensitivity and 95% specificity. No planimetry measurement could accurately discriminate those with multiple system atrophy with parkinsonism from patients with Parkinson disease. A corpus callosum posteroanterior gradient value of ≤191 was highly specific (97%) and moderately sensitive (75%) for the diagnosis of corticobasal degeneration versus all other groups. A midbrain-to-corpus callosum posteroanterior gradient ratio of ≤0.45 was highly indicative of progressive supranuclear palsy over corticobasal degeneration (sensitivity 86%, specificity 88%). CONCLUSIONS: MR imaging planimetry measurements are potent imaging markers of progressive supranuclear palsy and promising markers of corticobasal degeneration but do not seem to assist in the diagnosis of multiple system atrophy with parkinsonism.

Novel PANK2 mutation in the first Greek compound heterozygote patient with pantothenate-kinase-associated neurodegeneration

Pantothenate-kinase-associated neurodegeneration is the most common autosomal recessive form of neurodegeneration with brain iron accumulation. Less than 100 mutations in PANK2 gene (20p13) are responsible for classic and atypical cases. We report here the first Greek case of atypical pantothenate-kinase-associated neurodegeneration, confirmed by molecular analysis that revealed two trans-acting mutations. Our findings highlight the possible role of rare variants contributing to disease risk and possibly to variable clinical phenotype.