[Cranial pachymeningitis or unknown origin]. / Pachyméningite crânienne de cause indéterminée.

Pachymeningitis of unknown origin is uncommon and is usually associated with headaches, cranial nerve lesions and cerebellar ataxia. Magnetic resonance imaging is particularly contributive to diagnosis. The default diagnosis must however be confirmed by brain biopsy. Treatment is not well defined. Basically, corticosteroid therapy, or immunosuppressive therapy in case of failure, is known to have little effect on the brain lesion. We report here a case characterized by headache associated with partial regression of the radiographic lesions.

[Peripheral neuropathies caused by disulfiram]. / Les neuropathies périphériques dues au disulfirame.

Disulfirame is a rare cause of peripheral neuropathy in subjects with chronic alcoholism. We report here a case in a 42-year-old man and present the main clinical features and electrophysiological and pathology results. Disulfamine-induced peripheral neuropathy is dose-dependent and never occurs below 250 mg/d (1/2 tables of Espéral*). The pathogenesis is poorly understood.

A multiparametric data analysis showing the potential of localized proton MR spectroscopy of the brain in the metabolic characterization of neurological diseases.

We conducted an extended clinical evaluation of localized proton magnetic resonance spectroscopy (MRS) of the brain, performed on various brain diseases using short stimulated echo times. Pathologies studied were mainly multiple sclerosis, stroke, leukoaraiosis, AIDS-related leukoencephalopathies and glial tumors. Other miscellaneous pathologies were also studied. Magnetic resonance examination of the brain was conducted on a Siemens Magnetom SP63 (equipped with a 1.5 T magnet). Localized proton MRS was performed on a routine basis immediately after imaging, using the STEAM (stimulated echo acquisition mode) with a short echo time (20 ms) combined with a CHESS (chemical shift selective excitation) sequence. One or two VOI (8 ml) were examined. Data on 125 spectra were processed by principal component analysis (PCA) and conventional variance analysis. The following metabolite resonances were studied: inositol-glycine, taurine-scyllo-inositol, choline derivatives, phosphocreatine-creatine, aspartate, glutamine glutamate, N-acetylaspartate, acetate and lactate. PCA demonstrates that the different metabolic variables are independent. The analysis of groups of spectra clearly demonstrates that the metabolic profiles detected by localized MRS in various pathologies (i) differ significantly from controls, and (ii) allow a metabolic discrimination between groups of pathologies. Results of PCA are confirmed by variance analysis. Strokes are characterized by an increase in lactate concentration and leukoaraiosis by a decrease in inositol-glycine resonance. AIDS-related leukodystrophies are characterized by increases in lactate and choline concentrations. Reduction in N-acetylaspartate which is observed in most pathologies is not significant in the small lesions of white matter. Lactate has often been found in MS plaques, but no variation in the choline/phosphocreatine ratio was observed. GABA was tentatively assigned in the spectrum of a patient with epilepsy under sodium valproate treatment. This study illustrates the clinical feasibility of the technique, the value of a multiparametric data analysis in the definition of the pertinent variables characterizing the metabolic impairment, and the impact of localized proton MR spectroscopy of the brain in the assessment of cerebral suffering.

Nociceptive threshold in patients with epilepsy.

Clinical practitioners have often observed in the course of their daily work that the pain thresholds of epileptic patients seem to differ from those of healthy subjects. These patients can suffer from quite severe traumatic lesions without apparently experiencing any pain. Since they are usually under treatment for epilepsy, it is difficult to determine whether the absence of pain is due to these patients' epileptic condition or to its treatment, since most antiepileptic drugs also have analgesic effects. In the present study, it was proposed to assess the pain thresholds of 15 epileptic patients (10 with tonic-clonic seizures generalized at outset and 5 with temporal lobe epilepsy), by measuring the leg flexion nociceptive reflex (or RIII reflex) threshold: the stimulation threshold at which this reflex is triggered is known to be correlated with the pain threshold. The nociceptive threshold of the patients with generalized epilepsy was not found to differ from that of the control population, whereas that of the patients with temporal lobe epilepsy was spontaneously high and was not reversed upon injecting naloxone. These data are discussed from the point of view of the pain pathways and mechanisms possibly involved.

Metabolic characterization of neurological diseases by proton localized NMR spectroscopy of the human brain.

Proton localized Magnetic Resonance Spectroscopy (MRS) of the brain allows the non invasive detection of intracellular cerebral metabolites. Localized MRS has been performed using short stimulated-echo times in various neurological diseases including stroke, multiple sclerosis, and AIDS-related leukoencephalopathies. Principal component analysis (PCA) was used to determine the critical parameters defining the metabolic profile of normal and diseased brain. PCA clearly differentiates the demyelinating processes from ischaemic lesions and leukoencephalopathies. Localized MRS of the brain appears growingly as a tool of choice to discriminate, quantitate and assess cerebral metabolic damage in patients with neurological disorders.

[HTLV1 and coinfections]. / HTLV1 et coinfections.

After reminding the epidemiology of the HTLV1 infection the authors sum up the actually recommended diagnosis procedure. --Case finding by ELISA, confirmation by WESTERN-BLOT and/or RIPA (anti-gag and anti-env specificities), or even PCR which makes specific diagnosis of HTLV1/2. --Or if possible directly by PCR which has helped some authors to find provirus in seronegative people. Coinfections caused by HIV and by Strongyloides are the best documented. As a rule, HTLV1 seems to have rather a worsening effect on evolutiveness and on seriousness of the clinical picture caused by mixed infections, than the contrary (possibly for lack of experience and owing to slow evolution of HTLV1 pathology). Several mechanisms have been proposed concerning coinfections with HTLV1 and HIV (in vitro studies). --Immortalization of CD4 lymphocytes infected with HTLV1 by stimulating both IL2 and its receptor, and by activating lymphocytes with translocation of the replicating factor NF k B in the nucleus, on a promoting sequence of HIV-LTR by stimulating its replication. --The product of HTLV1 tax gene would also have a transactivating effect on the provirus HIV-LTR replication. And finally infection with HTLV1 may facilitate HIV by inducing CD4, molecule expression in non-expressing cells. In Strongyloides modulating effects of HTLV1 on the immune response would facilitate and predispose Strongyloides stercoralis multiplication. As far as other coinfections are concerned (caused by viruses, by parasites: such as malaria, filariasis, trypanosomiasis or by bacteria), epidemiological convergence (risk factors, and geographic distribution) on the one hand, and immunological dysregulation induced by the other, on the other hand, would be of varying importance. In conclusion, these data ask more questions than they answer. But it seems to be established that detection of HIV and Strongyloides should performed in every case HTLV1 carries and vice versa.

Q fever meningoencephalitis in five patients.

Within the last four years, we have observed five patients with epidemiological, clinical, and serological features that were consistent with Q fever meningoencephalitis. Attempts to isolate Coxiella burnetii from the cerebrospinal fluid of two patients were unsuccessful. Neurological features ranged from coma, general seizures, confusion, to palsy and meningitis. All patients were febrile. These patients were neuroradiologicaly investigated. Since 1984, four other cases have been reported in the literature. Antibiotics with good penetration into the cerebrospinal fluid, such as new quinolones, may be useful for treatment of confirmed cases. Q fever should be considered as a possible etiology of meningitis in endemic areas, and diagnosis should be confirmed by serology.

[Ataxic hemiparesis and simultaneous supra- and subtentorial hematomas]. / Hémiparésie ataxique et hématomes simultanés sus et sous-tentoriels.

In a chronically hypertensive woman with a rapidly developing right ataxic hemiparesis syndrome, computed tomography and magnetic resonance imaging (MRI) revealed two small unrelated hemorrhages: one in the posterior limb of the left internal capsule, the other in the right cerebellar hemisphere. In this patient, the ataxic hemiparesis syndrome might have resulted either from the association of the two lesions or from the capsular hemorrhage alone. The rarity of simultaneous hypertensive hematomas and the value of MRI in the diagnosis are underlined.

[High resolution NMR spectroscopy of CSF: methodological issues and perspective clinical applications]. / La spectroscopie de RMN à haute résolution du LCR: problèmes méthodologiques et perspectives d'applications cliniques.

High resolution proton nuclear magnetic resonance (NMR) spectroscopy is a new analytical technique which allows to readily identify and quantitate a variety of key metabolites in cerebrospinal fluid (CSF) in relation to normal and pathological brain activity. Proton NMR spectroscopy can be performed on native CSF, with or without addition of exchange reagent (NH4Cl). The analysis of native CSF provides qualitative information (identification) of metabolites or xenobiotics present in the fluid. Alternately, CSF can be lyophilized and dissolved in deuterated water. This concentration offers 2 advantages: additional compounds are detected and a precise quantification of all CSF metabolites can be obtained. Both protocols require a very small volume of CFS (1-2 ml). The high informational content available on the NMR spectra of CSF, the ease-of-use of NMR spectroscopy and its cost effectiveness concur to predict that this analytical approach will keep developing to completement the array of existing tests which are already routinely performed on CSF.

[Meningoencephalitis caused by Coxiella burnetii]. / Méningoencéphalite due à Coxiella burnetii.

Meningoencephalitis caused by Coxiella burnetii is exceptional and its clinical presentation is varied. We report a case which presented as transient central neurological deficits and intracranial hypertension without fever. The condition was diagnosed by indirect immunofluorescence.

[Tendon vibrations as a tool for clinical investigation of the myotatic loop]. / Les vibrations tendineuses comme moyen clinique d'exploration de la boucle myotatique.

The degree of alteration of the myotatic loop was evaluated in 6 patients with polyradiculoneuropathy by studying deep reflexes and vibratory motor responses. The results showed that the reflex motor responses induced by vibration reappeared 2 to 4 weeks before the deep reflexes. Vibrations, therefore, could be a useful tool for the clinical follow-up of polyradiculoneuropathy.

[Paralysis of the right arm caused by vertebral arteriovenous fistula]. / Paralysie du membre supérieur droit par fistule artérioveineuse vertébrale.

Traumatic vertebral arteriovenous fistulas rarely result in neurological disorders. We report a case of upper limb paralysis caused by a C5-C6-C7 radiculopathy, 44 years after a trauma and successfully treated by surgery and embolization.