Vascular parkinsonism or idiopathic NPH? New insights from CSF pressure analysis.

Differential diagnosis between vascular parkinsonism (VP) and idiopathic normal pressure hydrocephalus (iNPH) is particularly challenging due to similar clinical and neuroradiological features. The objective of this study is to differentiate VP with radiological evidence of ventricular enlargement (REVE) from iNPH on the basis of cerebrospinal fluid (CSF) hydrodynamics. CSF pressure components were investigated in patients with a clinical diagnosis of VP and REVE. Data of eight patients (seven men; age 76 ± 3.9 years; disease duration 26.5 ± 15.6 months) were evaluated. CSF opening pressure values were normal in all patients. Also, mean CSF pressure values during short-term monitoring were normal, except in one patient. Four out of the eight patients had raised values of pulse wave amplitude (PWA) during the opening phase (mean ± SD 57.1 ± 19.9 mmH2O), meanwhile during short-term monitoring, seven out of the eight patients showed raised values of mean PWA (76.8 ± 23 mmH2O). We found that most of patients with clinical characteristics of VP and REVE showed elevated PWA during the short-term monitoring of CSF pressure as observed in iNPH patients. Patients clinically identified as VP may be part of the clinical spectrum of iNPH.

Sporadic motor neuron disease in a familial novel SOD1 mutation: incomplete penetrance or chance association?

Cu/Zn superoxide dismutase (SOD1) gene mutations have been reported in familial and sporadic amyotrophic lateral sclerosis (ALS). We report a novel G61R SOD1 mutation in a patient with a distinct phenotype including prominent lower motor neuron dysfunction, proximal weakness and atrophy with asymmetrical onset in the thigh and buttock and relentless clinical course. The G61R mutation segregated in three unaffected relatives including the 80-year-old mother and two of the proband's siblings. Potential mechanisms include an autosomal dominant condition with reduced penetrance or a chance association.

Screening for Fabry disease in unknown origin axonal polyneuropathy: to do or not to do, this is the question!

Fabry disease (FD) is a systemic X-linked lysosomal disorder. A 'peripheral nerve variant' of FD has been hypothesized in subjects with neuropathy, without the early manifestations of the classic phenotype. A cohort of undiagnosed neuropathy patients with chronic polyneuropathy of undetermined aetiology and demyelinating neuropathy, unresponsive to immunomodulating treatment, were screened for FD. A total of 103 patients (64% males), were enrolled. No typical pathogenetic mutations for FD were identified. We are aware that the study sample was very small, but only a large, unfeasible theoretical sample size could demonstrate a statistically significant increased prevalence of FD in neuropathy patients, as peripheral neuropathy of undetermined cause is uncommon and there is a low prevalence of FD in the general population. Therefore, we are of the opinion that including tailored FD screening in the neuropathy diagnostic work-up, particularly when there are additional clinical characteristics, should be considered.