[Atypical encephalitis in a 20-year-old soldier]. / Atypische Enzephalitis eines 20-jährigen Wehrpflichtigen.

We report a patient with encephalitis who had been diagnosed with an unspecific aetiology. During follow-up, pneumonia was identified due to Mycoplasma pneumoniae infection that could also be confirmed as causal for the brain inflammation. Despite the initially critical clinical situation, the patient's condition improved under specific antibiotic treatment. Pathophysiologic, differential diagnostic, and therapeutic implications are discussed, and guidelines for diagnosis are proposed.

Alterations of cortical electrical activity in patients with sacral neuromodulator.

OBJECTIVES: Sacral neuromodulation represents chronic stimulation of the sacral (S3) nerve. So far, the mode of action and neuro-anatomical basis is unclear. Sacral reflex mechanisms as well as pontine or cortical centers of modulation have been postulated. Our aim was to evaluate possible alterations in electroencephalogram (EEG) activity as an indicator of a supraspinally mediated mechanism of sacral neuromodulation. MATERIALS AND METHODS: We analyzed serial EEGs (apparatus: Kölner Vitaport System) using electrodes placed at Fz, Cz, Cz' and Pz in 10 patients. Subsequently, the sacral (S3) nerve was stimulated by means of an impulse generator (Medtronic, Interstim 3023) using an on-off paradigm with a 1.5s "on" interval followed by a 10s stimulation break. Raw data were analyzed using both Matlab 4.0 software and a specially developed averaging routine. RESULTS: All patients demonstrated a cortical potential complex following sacral root stimulation with an early electronegative component at 50 ms with a mean amplitude of 23 microV followed by a late potential component with a mean latency of 253 ms and a mean amplitude of 5 microV, both with a maximum at Cz, corresponding to the post-central gyrus. This finding occurred irrespective of patient's reports of actually feeling the neuromodulator being switched on and off. CONCLUSION: In neuromodulation responders, both short and long latency cortical potentials can be reproduced with a maximum at the sensory cortical area. Although these potentials are similar to cognitively mediated "event-related potentials", they are clearly distinct from any subjective sensory or even painful response since several patients of this series have not been able to feel any neuromodulator action. Therefore, this pilot study indicates a supraspinally mediated site of modulation, most probably in sensory cortex areas.

Subacute NO generation induced by Alzheimer's beta-amyloid in the living brain: reversal by inhibition of the inducible NO synthase.

Glial activation contiguous to deposits of amyloid peptide (Abeta) is a characteristic feature in Alzheimer's disease. We performed complementary in vitro and in vivo experiments to study the extent, kinetics, and mechanisms of microglial generation of nitric oxide (NO) induced by challenge with Abeta. We showed that Abeta fibrils dose-dependently induced a marked release of stable metabolites of NO in vivo that was strikingly similar regarding extent and temporal profile to the one in the parallel designed microglial cell culture experiments. However, costimulation with interferon gamma, which was a prerequisite for Abeta-induced NO generation in vitro, was not required in vivo, demonstrating that factors are present in the living brain that activate glial cells synergistically with Abeta. Therefore, in Alzheimer's disease, deposits of Abeta fibrils alone may be sufficient to induce a chronic release of neurotoxic microglial products, explaining the progressive neurodegeneration associated with this disease. Our observation that systemic administration of selective iNOS inhibitors abolishes Abeta-induced NO generation in vivo may have implications for therapy of Alzheimer's disease.

Alcohol-related acute axonal polyneuropathy: a differential diagnosis of Guillain-Barré syndrome.

BACKGROUND: Chronic axonal polyneuropathy is a well-known clinical sequela of excessive alcohol consumption; however, acute axonal polyneuropathy related to alcohol abuse is less well recognized. OBJECTIVE: To describe alcohol-related acute axonal polyneuropathy in 5 chronic alcoholics who developed ascending flaccid tetraparesis and areflexia within 14 days. METHODS: Case series with clinical, laboratory, electrophysiological, and, in 1 patient, biopsy data. RESULTS: All 5 patients consumed a daily average of 250 g of alcohol, and 4 had lost a substantial amount of weight recently. Additional clinical features included painful paresthesia, myalgia, and glove and stocking-type sensory loss. Repeated cerebrospinal fluid examinations failed to show the marked increase of protein concentration with normal cell count typical of Guillain-Barré syndrome, although the protein level was mildly elevated in 1 patient. Blood laboratory findings were consistent with longstanding alcohol abuse. Compound muscle and sensory nerve action potentials were absent or reduced, while conduction velocities were normal or mildly reduced. Three to 4 weeks after onset, needle electromyography displayed moderate to severe fibrillations and positive sharp waves in addition to normal motor unit potentials, indicating an acute axonal polyneuropathy; this was confirmed by sural nerve biopsy in 1 patient. CONCLUSIONS: Excluding other factors, we assume that in these patients the combination of alcohol abuse and malnutrition caused severe acute axonal polyneuropathy. Its distinction from Guillain-Barré syndrome is important because treatment requires balanced diet, vitamin supplementation, and abstinence from alcohol, while immunotherapy may not be indicated.

The influence of image resolution on the positron emission tomographic measurement of caudate glucose consumption.

The aim of this study was to investigate the influence of image resolution on (a) relative and absolute values of caudate glucose consumption (rCMRGlc) determined by positron emission tomography (PET), and (b) the detection of significant differences in these metabolic values between groups of subjects. For this purpose, raw data of cerebral accumulation of fluorine-18 fluorodeoxyglucose (FDG) obtained in 11 normal subjects and in nine patients with unilateral thalamic infarction were reconstructed using filtered backprojection with four different cut-off frequencies (CFs), yielding images with a transaxial resolution of 5.7, 7.1, 8.9 and 11 mm (full-width at half-maximum; FWHM). Absolute values of caudate rCMRGlc decreased significantly by more than 30% over the range of image resolutions studied. Bilateral ratios of caudate rCMRGlc were insensitive to variations in image resolution. Levels of significance assessing the differences in mean metabolic values between patients and controls were all below 0.01. They were, however, slightly better at image resolutions of 7.1 and 8.9 mm than at a resolution of 5.7 mm. These data indicate (a) that relative values of rCMRGlc are better suited to compare quantitative results from different PET cameras than are absolute values, and (b) that the CF used for the filtered back-projection exerts a small but not negligible influence on levels of significance assessing differences in metabolic values between groups of subjects.

New aspects of calcium antagonists for treatment of cerebrovascular disease.

Cerebrovascular infarction can be subdivided into two different categories: cerebral hemorrhage and cerebral ischemia. Although the use of calcium antagonists for the treatment of subarachnoid hemorrhage has been established in many series, the benefit of these drugs for the treatment of cerebral hemorrhage is inconclusive, and we lack considerable evidence of its application in acute ischemic stroke. Inconclusive data have been reported from experimental studies using different pharmacological models and different protocols; however, various clinical studies have suggested that calcium antagonists may be useful in improving the neurological and functional outcome of the patient due to reduced infarct size and the properties of the drug to improve tissue metabolism in remote cortical territories. So far, however, these studies failed to establish the efficacy of the drug unequivocally. This may be due to the considerable amount of patients included with small or rapidly recovering neurological deficits and to the delay between onset of symptoms and start of treatment (ranging between 48 and 72 h).

Effect of nimodipine on acute ischemic stroke. Pooled results from five randomized trials.

In a review of pooled data from five double-blind, placebo-controlled studies of nimodipine in acute ischemic stroke, we compared the effect of 120 mg nimodipine given orally with that of placebo. In the five studies, 871 patients were followed, and 781 adhered to entry and inclusion criteria. End points were mortality and outcome at the end of the treatment period (21 or 28 days). Outcome was assessed with Mathew's scale and the physician's clinical judgement. The treatment and control groups were well matched with respect to demographic data, risk factors, and baseline Mathew scores. In the treatment group, 34 patients (7.9%) died during the treatment period, whereas 54 (12.3%) in the control group died, corresponding with a mortality reduction of 36%. Significantly less neurologic impairment at the end of the treatment period was documented under nimodipine treatment, and this impairment improved more in patients with moderate-to-severe stroke (baseline Mathew score less than 66) if administration of nimodipine occurred within 12 hours after stroke onset or if the patient was more than 65 years old. The overall incidence of adverse reactions was relatively modest, and these were of minor severity; only a few appeared to have more than a remote relation to the study medication.