Early electrophysiological findings in Fisher-Bickerstaff syndrome. / Hallazgos electrofisiológicos precoces en síndrome Fisher-Bickerstaff.

INTRODUCTION: The term Fisher-Bickerstaff syndrome (FBS) has been proposed to describe the clinical spectrum encompassing Miller-Fisher syndrome (MFS) and Bickerstaff brainstem encephalitis. The pathophysiology of FBS and the nature of the underlying neuropathy (demyelinating or axonal) are still subject to debate. This study describes the main findings of an early neurophysiological study on 12 patients diagnosed with FBS. PATIENTS AND METHODS: Retrospective evaluation of clinical characteristics and electrophysiological findings of 12 patients with FBS seen in our neurology department within 10 days of disease onset. Follow-up electrophysiological studies were also evaluated, where available. RESULTS: The most frequent electrophysiological finding, present in 5 (42%) patients, was reduced sensory nerve action potential (SNAP) amplitude in one or more nerves. Abnormalities were rarely found in motor neurography, with no signs of demyelination. The cranial nerve exam revealed abnormalities in 3 patients (facial neurography and/or blink reflex test). Three patients showed resolution of SNAP amplitude reduction in serial neurophysiological studies, suggesting the presence of reversible sensory nerve conduction block. Results from cranial MRI scans were normal in all patients. CONCLUSION: An electrophysiological pattern of sensory axonal neuropathy, with no associated signs of demyelination, is an early finding of FBS. Early neurophysiological evaluation and follow-up are essential for diagnosing patients with FBS.

Reversible acute leukoencephalopathy as a form of presentation in cerebral amyloid angiopathy.

BACKGROUND: Cerebral amyloid angiopathy (CAA) may present as cerebral haemorrhage, cerebral infarction and periventricular white matter lesions. Reversible leukoencephalopathy is a rare manifestation of CAA. AIMS OF THE STUDY: To describe two patients with reversible acute leukoencephalopathy as the first manifestation of CAA. PATIENTS: Two consecutive patients were admitted to our neurology department with transient focal neurological symptoms. They showed reversible focal leukoencephalopathy on magnetic resonance imaging (MRI). CAA was finally diagnosed in both, and pathologically confirmed in one. The latter patient showed multiple foci of petechial bleeding in the cortex and subcortex in T2-weighted GRE sequences, suggestive of CAA. CONCLUSION: Reversible acute focal leukoencephalopathy may be an infrequent clinical and radiological pattern of CAA.

18F-FDG PET/CT in the evaluation of POEMS syndrome.

In POEMS syndrome the identification and biopsy of an osteosclerotic lesion or a lymph node typical of Castleman's disease (CD) is essential to establish the diagnosis and plan appropriate treatment. We report four patients in whom the localisation and identification of diagnostic bone lesions or lymphadenopathies were guided by fluorodeoxyglucose positron emission tomography integrated with computerised tomography (FDG PET/CT). FDG PET/CT identified bone lesions not detected with other techniques in one patient, and revealed hypermetabolic characteristics in bone lesions or adenopathies in the others, thus guiding the diagnostic biopsy in those with hypermetabolism. In conclusion, FDG PET/CT may be useful in detecting and selecting bone lesions and lymph nodes for biopsy in patients with suspected POEMS syndrome.