Acute/subacutae demyelinating polyneuropathy in Parkinson's Disease patients on levodopa-carbidopa intestinal gel therapy: systematic review with new case report.

Polyneuropathy (PNP) is a known complication of levodopa-carbidopa intestinal gel (LCIG) therapy of advanced Parkinson's Disease (PD). The overall prevalence of PNP in PD is estimated to be 42.1% (as shown in a review by Romagnolo et al. 2018), and the most common type is chronic axonal polyneuropathy. There is a group of acute/subacute onset demyelinating polyneuropathies, which is far less common, although it seems to be an important factor leading to the rapid discontinuation of LCIG treatment. In this systematic review, we present data on demyelinating polyneuropathy with acute/subacute onset; we identified nine papers including prospective assessments and case reports, with detailed information on 15 patients. In all patients, despite treatment with corticosteroids, intravenous immunoglobulins (IVIG) or plasma exchange (PE), the LCIG therapy was terminated. We also present a case of subacute demyelinating polyneuropathy with effective treatment and continuation of LCIG therapy.

Neuroimaging in Parkinson's Disease: necessity or exaggeration?

INTRODUCTION: Neuroimaging plays an increasingly important role in the diagnosis of parkinsonian syndromes. AIM OF THE STUDY: In this paper, the authors elaborate on the necessity of using magnetic resonance imaging (MRI) in Parkinson's Disease (PD) and its potential role in differential diagnosis versus other neurodegenerative parkinsonian syndromes such as dementia with Lewy bodies, multiple system atrophy, progressive supranuclear palsy and corticobasal syndrome. STATE OF THE ART: The currently known characteristic abnormalities are listed and tabulated, current recommendations are summarised and sample images are provided. As routine MRI scanning in PD remains controversial, the authors' aim is to show the pros and cons in clinical practice. Additionally, the rationale for functional imaging examination, including [123I]-FP-CIT SPECT (DaTSCAN) and [99mTc]- HMPAO-SPECT, [18F]-FDG-PET, [123I]-mIBG-SPECT is discussed. CLINICAL VIGNETTE: This paper is accompanied by two illustrative clinical cases in which neuroimaging studies played a key role in diagnosis and further management. CONCLUSIONS: Neuroimaging can be helpful in differentiating PD from both atypical and symptomatic parkinsonism. Nevertheless, extensive neurological assessment in a majority of PD cases is sufficient to make a diagnosis. A network of specialists in movement disorders should be established in order to enable better, faster and more precise diagnosis of parkinsonism.