Cerebellar atrophy and prognosis after temporal lobe resection

OBJECTIVE

Experimental data indicate inhibitory effects of the cerebellum on seizure activity. Structural damage such as cerebellar atrophy, which is a common finding in patients with chronic epilepsy, may reduce these effects.

METHODS

Outcome after temporal lobectomy was studied in 78 consecutive patients, with or without cerebellar atrophy diagnosed by MRI.

RESULTS

Thirty five patients (45%) showed cerebellar atrophy. At a mean follow up of 14.6 (range, 6-40) months, 50 patients (64%) had no postoperative seizures. In these patients, the frequency of cerebellar atrophy was significantly lower (34%) than in patients who relapsed (64%, p < 0.01). Occurrence of generalised tonic-clonic seizures (GTCS) within two years before surgery, occurrence of GTCS at any time preoperatively, long duration of epilepsy, and older age at surgery were also associated with recurrence of seizures. Multiple logistic regression analysis suggested occurrence of GTCS within two years before surgery and cerebellar atrophy as the main predictive indicators. When both factors were present, the percentage of patients remaining seizure free since surgery fell to 30%, compared with 60% when only GTCS were present, 78.6% when only cerebellar atrophy was present, and 87.5% when both factors were absent.

CONCLUSIONS

Cerebellar atrophy shown by MRI was a frequent finding in surgically treated patients with temporal lobe epilepsy. The presence of cerebellar atrophy seems to worsen the prognosis after temporal lobe resection.

Influence of ethosuximide on valproic acid serum concentrations

In the therapy of absence epilepsies, a combination of ethosuximide (ESM) and valproic acid (VPA) is sometimes necessary for a successful seizure control. Previous studies of the interaction between ESM and VPA revealed contradictory results. We investigated the influence of ESM on VPA serum concentrations in children with epilepsy. In case of ineffectiveness of the drug, ESM was withdrawn (n = 9). Four children treated with VPA got ESM additionally because their seizure control was insufficient with VPA alone. Two children had bromide, and one clobazam as comedicament. Both of these antiepileptic drugs (AEDs) do not have any known interactions with ESM or VPA. Serum levels of VPA were higher in monotherapy than in combination with ESM (120.0 +/- 20.1 micrograms/ml; range, 88.9-153.4 micrograms/ml; vs. 87.0 +/- 13.1 micrograms/ml; range, 67.4-108.0 micrograms/ml). The difference was statistically significant (P < 0.01). After stopping ESM the serum concentrations of VPA rose about 36.7%; when combined with ESM they fell about 28.3%. Neither the age of the patients nor the serum concentrations of ESM influenced significantly the changes of VPA serum levels in either group. The mechanism of ESM to influence the serum levels of VPA remains unknown. ESM has no known enzyme inducing properties. The interaction of ESM and VPA ought to be considered in a combination therapy of these drugs.

[Current status in the prevention of Mycobacterium avium complex infections in patients with HIV infection]

Mycobacterium avium complex (MAC) infections in AIDS are increasingly common and contribute to the mortality in severe immunocompromised patients. In this paper, we review the published studies on the prevention of the MAC infections. Rifabutin and the new macrolides (clarithromycin, azithromycin) are shown to be effective in the primary prevention. However, they can fail and are difficult to manage with the antiretroviral treatment, specially antiproteases and prevention of the other opportunistic infections. For the prevention of the relapse of the MAC infections, it is necessary to give a prolonged treatment with a bio-therapy associating at least a new macrolide with rifabutin or ethambutol, which is also difficult to manage with the other treatments.

Pulmonary toxoplasmosis in patients infected with human immunodeficiency virus: a French National Survey

We reviewed all cases of pulmonary toxoplasmosis (PT) that were documented by detection of Toxoplasma gondii in bronchoalveolar lavage fluid specimens during a French nationwide review of extracerebral toxoplasmosis in patients infected with human immunodeficiency virus (HIV). Only 64 cases of proven PT were recorded during the 33-month survey. The patients were similar to other patients with AIDS in terms of age, sex, and risk factors for HIV infection. PT occurred mainly in patients with advanced immunodeficiency (mean [+/- SD] CD4+ lymphocyte count, 40 +/- 75/mm3). Clinical features of PT usually include fever, cough and dyspnea; the associated radiological findings were mainly diffuse interstitial infiltrates. Serological data were uninformative. The treatment for PT was the same as that for cerebral toxoplasmosis. A clinical response was observed for 47% of patients, 23% of whom relapsed. Twenty-four patients (37%) died of toxoplasmosis, and 17 (27%) died of other causes. The median survival time was 150 days. We conclude that PT is an infrequent but severe infection in HIV-patients in France.

[Malnutrition and HIV infection]

The wasting syndrome is well known in HIV infected patients. Predominant free fatty mass deletion is achieved. The weight loss results from decrease of food intake, from gut disorders due to HIV or opportunistic infections. Metabolic disorders are reported too. Breakdown of carbohydrates and proteins presents energy source. Raised free fatty acid turn over and hypertriglyceridemia are reported. Polyunsatured fatty acid level is raised inducing free radicals increase. Free radicals delete immune functions (apoptosis). Vitamin and trace element decrease worsen negative effects of free radicals.

Relationship between ischemic damage and concentrations of phenytoin and phenobarbital in the brain cortex of epileptic patients in vegetative state at death

Post-mortem concentrations of phenytoin (PHT) and phenobarbital (PB) were determined by high-performance liquid chromatography in the cortical matter of specified brain regions and in the serum (total and free) from 3 epileptic males in vegetative state and compared to the data of 45 deceased epileptic control patients. The duration of the vegetative state was 12 days, 15 days or about 4 months until death and was associated with corresponding stages of generalized ischemic brain damage. The histological examination was completed by immunohistochemical and morphometric methods. According to other investigators nerve cells are the major binding sites for PHT and PB in the cerebral cortex of rodents. But, in the 3 comatose patients the PHT and PB concentrations of the isocortex and neocerebellum were not significantly decreased in comparison with the control patients despite necrosis and loss of neurons as well as other distinct tissue alterations. The results strongly favor the non-specific binding of PHT and PB to cells and subcellular structures of the brain-mainly based on simple physico-chemical principles.

Complete nucleotide sequence of a cryptic plasmid, pBAW301, from the ruminal anaerobe Ruminococcus flavefaciens R13e2

The complete nucleotide sequence of a cryptic plasmid designated pBAW301, from the Gram-positive ruminal bacterium Ruminococcus flavefaciens R13e2, has been determined. This plasmid is 1768 bp in size and has an overall G+C content of 43.5%. Computer analysis of the sequence data revealed an open reading frame, ORF1 (256 amino acids), which is similar to the Rep protein of the Bacillus borstelensis plasmid pHT926. ORF1 is preceded by Shine-Dalgarno and Escherichia coli-10 and -35 like sequences. Nine smaller open reading frames showed no significant homologies to known protein sequences. Analysis of replication intermediates and the nucleotide sequence indicate that the plasmid does not replicate by a rolling-circle mode of replication similar to other plasmids from Gram-positive bacteria. Moreover, sequences typical of theta replication origins were not found in the nucleotide sequence of pBAW301. These data suggest that this plasmid either replicates by an as yet undescribed mechanism, or represents a new class of theta replicating plasmids.

Lack of influence of histopathological changes on carbamazepine and carbamazepine-10, 11-epoxide concentrations in the brain cortex of epileptic patients

Post-mortem concentrations of carbamazepine (CBZ) and its anticonvulsive metabolite carbamazepine-10,11-epoxide (CE) were determined in different lesions of the cerebral cortex and in the serum (total and free) from 13 epileptic patients. Twenty cortical specimens were obtained from the superior frontal gyrus, the temporopolar region and the neocerebellum. The cortical samples showed various pathological changes characterized by augmented glial cells, fibre gliosis or ulegyria as well as abundant corpora amylacea or encephalitic signs of viral type besides neuronal depletion. The CBZ and CE concentrations in the 20 cortical lesions were not significantly decreased when compared to the control specimens of 32 epileptic patients without essential histopathological alterations of the specified cortical areas (p < 0.05). A comparable result had been found in our former study on phenytoin (PHT) and phenobarbital (PB). Six patients with cortical lesions of the present series had already been included in this PHT/PB study. Five of these patients revealed unchanged CBZ and CE as well as PHT and PB concentrations. Only in one neocerebellar specimen the CE concentration was just above the upper 95% confidence limit of the control group. But, most probably this finding has no further relevance. The results greatly favour the nonspecific binding of CBZ and CE to cerebral tissue constituents.

The Duke criteria for diagnosing infective endocarditis are specific: analysis of 100 patients with acute fever or fever of unknown origin

The recently proposed Duke criteria were confirmed to be more sensitive than the former Beth Israel criteria for the diagnosis of infective endocarditis (IE). To assess the specificity of the Duke criteria, we reviewed the records of 100 patients admitted to two internal medicine wards because of acute fever or fever of unknown origin (FUO). IE was considered a possible diagnosis for all patients who had had at least two blood cultures performed and one transthoracic echocardiogram obtained. The diagnosis of IE was rejected in all cases in accordance with the Duke criteria (i.e., a firm alternate diagnosis [n = 23], resolution of symptoms with no antibiotics [n = 39], or both reasons [n = 38]). To calculate the specificity of the Duke criteria, all 100 cases were then reclassified according to these criteria as if the diagnosis of IE had not been rejected. Only one patient, who probably did not have IE, was reclassified as having clinically definite IE. The specificity of the Duke criteria could therefore be calculated to 0.99 (95% confidence interval, 0.97-1). Although the design of the study may have resulted in a slight overestimation of the specificity rate, we conclude that the Duke criteria are highly specific for ruling out IE in patients with acute fever or FUO who are at low risk for IE.

Comparative efficacy of sparfloxacin in comparison with amoxycillin plus ofloxacin in the treatment of community-acquired pneumonia. French Study Group

A prospective, placebo controlled double-blind, randomised study comparing oral sparfloxacin 200 mg once daily following a 400 mg loading dose on day 1 with an oral combination of amoxycillin 1 g tid plus ofloxacin 200 mg bid was conducted in 211 hospitalised patients with community-acquired pneumonia. Patients were included in the study if they were aged > 65 years or had failed a previous course of antibacterial therapy. The duration of treatment was 10 days. The overall efficacy rates for the sparfloxacin and amoxycillin plus ofloxacin treatment groups were 91.9% and 81.5%, respectively, in evaluable patients at the end of treatment. Age or prior failure of antibacterial therapy did not affect the overall success rate of sparfloxacin. The safety profile of sparfloxacin was similar to that of the antibacterial combination. This study demonstrated that sparfloxacin given once daily is a suitable therapy for the treatment of community-acquired pneumonia in the elderly or in patients with failure of previous antibiotic therapy.

[Prognostic factors of Pneumocystis carinii pneumonia in AIDS]

OBJECTIVES

Identify prognosis factors in Pneumocystis carinii pneumonia at diagnosis and construct a model to predict mortality according to these prognosis factors.

METHODS

Seventy-seven consecutive cases of proven AIDS-related Pneumocystis carinii pneumonia (67 men, 10 women, mean age 37.2 years) were reviewed to determine the most accurate initial prognostic factors and estimate an individual prediction of death. A stepwise logistic regression analysis was performed. Three kinds of data were entered into the logistic model: historical data, clinical and laboratory data obtained within the first 24 hours of diagnosis, and specific data related to chest X-ray and bronchoalveolar lavage results.

RESULTS

The sum of arterial partial pressure of oxygen and carbon dioxide (PaO2 + PaCO2) and serum albumin level best predicted a fatal outcome in multivariate analysis.

CONCLUSION

The logistic equation provided by the model might be used to accurately and quickly identify the patients with severe Pneumocystis carinii pneumonia who might benefit from supportive intensive care.

Striatal dopamine receptors and adenylyl cyclase activity in a rat model of alcohol addiction: effects of ethanol and lisuride treatment

In this report a novel animal model of spontaneous development of alcohol and drug addiction was used. Addiction to ethanol was induced in male Wistar rats (free choice between ethanol solutions and water for 11 mo). After 36 wk of alcohol deprivation these rats (series A) had ingested 3.4 +/- 0.4 g ethanol/kg/day. Age-matched, "controlled" alcohol consumers (series C: free choice for 8 wk) had ingested only 1.6 +/- 0.4 g/kg/day (P < .001). Two additional series of addicted (AL) and controlled alcohol-consuming rats (CL) received lisuride (90 micrograms/kg/day) for 8 wk concomitantly with the self-administered ethanol and again during the last week before death. Ethanol intake was increased by lisuride treatment in both groups (AL: 4.1 +/- 0.3 g/kg/day; CL: 2.7 +/- 0.4 g/kg/day; P < .05). Four months before death the alcohol was withdrawn. After this period of abstinence the in vitro dose-response curves for striatal dopamine D-1 receptor-stimulated adenylyl cyclase activity were determined (with eight concentrations of dopamine between 50 nM and 30 microM). Both lisuride-treated (AL) and untreated ethanol-addicted rats (A) displayed a significant (P < .01) increase in the effective concentration required to induce 50% of the response (EC50) as compared with controlled drinkers (C: 720 +/- 150 nM; A: 1820 +/- 390 nM; CL: 590 +/- 110 nM; AL: 1050 +/- 160 nM). Lisuride treatment increased forskolin- (10 microM) stimulated adenylyl cyclase activity and the Bmax of high-affinity [3H]DA binding to the D-1 site.(ABSTRACT TRUNCATED AT 250 WORDS)

Influences of housing conditions and ethanol intake on binding characteristics of D2, 5-HT1A, and benzodiazepine receptors of rats

The effects of different housing conditions and ethanol treatment (6 vol % in the drinking water) on the in vitro binding characteristics of striatal dopaminergic D2 ([3H]spiperone), hippocampal serotonergic 5-HT1A ([3H]8-OH-DPAT), and cortical benzodiazepine ([3H]flunitrazepam) receptors have been examined. Social deprivation due to contact caging, short- (1 day) and long-term isolation (5 weeks) yielded a significant decrease of striatal D2 receptor density with the greatest decrease after long-term isolation (-21% Bmax) without changes of Kd in comparison to group animals. The effect of ethanol on striatal D2 receptor density depended on the housing conditions. Whereas ethanol treatment reduced receptor density of group animals (down to 88%), chronic exposure to ethanol under long-term isolation elicited no significant alteration of D2 receptor density compared with group animals. Different housing and ethanol treatment had no effect on 5-HT1A receptor affinity and density. Alterations of benzodiazepine receptor density were not found, but social deprivation as well as ethanol treatment of group animals caused an increased affinity of [3H]flunitrazepam (reduced Kd value). These results indicate that different housing conditions of adult rats evoked significant alterations in D2 and benzodiazepine receptor binding assays, which were modified by ethanol treatment in the case of striatal D2 receptor density.

Lower survival in AIDS patients receiving dapsone compared with aerosolized pentamidine for secondary prophylaxis of Pneumocystis carinii pneumonia. Study Group

A randomized, unblinded study compared aerosolized pentamidine, 300 mg every month, and dapsone, 50 mg/day, for secondary prophylaxis of pneumocystosis in 196 AIDS patients. The study was prematurely discontinued due to excess mortality in the dapsone group. After a mean follow-up of 13 +/- 6.4 months, 22 (21%) of 103 patients in the pentamidine group were dead compared with 39 (42%) of 93 receiving dapsone; the estimated mortality rates at 18 months were 24.6% and 53.1%, respectively (P < .003, log-rank test). A negative interaction was observed between zidovudine and dapsone (P < .049, interaction test of Cox model), and the mean CD4 cell count during the study was lower in the dapsone (49 +/- 61/mm3) than in the pentamidine group (83 +/- 88/mm3; P < .002, t test). The lower survival might also be related to the oxidative effect of dapsone or to the addition of iron protoxalate to dapsone in this study. These results suggest caution in using dapsone as long-term therapy in advanced human immunodeficiency virus infection, especially in those receiving zidovudine.

Changes of G-protein levels in platelet membranes from alcoholics during short-term and long-term abstinence

The levels of G alpha i2-protein and the G beta gamma-heterodimer were measured in platelet membranes of non-alcoholics, non-alcoholics after an ethanol load (1 g/kg body weight) and of alcoholics under various conditions. The findings were correlated with the activation of the adenylyl cyclase (AC) by various agents. The activation of AC was facilitated by acute ingestion of ethanol. This could not be explained by changes of the G-proteins determined because the levels of the G alpha i2-protein increased, whereas those of the G beta gamma-proteins remained in the control range. The alcoholics were divided into two groups on the day of admission: those with ethanol still present in the blood (intoxicated alcoholics) and those acutely withdrawn within the last 48 h (ethanol absent from the blood). The intoxicated alcoholics had elevated G alpha i2-protein levels in contrast to the acutely withdrawn patients, who did not. This observation suggests rapid changes of the G-protein levels. By analysing the inhibitory efficacy of the G-proteins on AC, it was found that the concentration of the G beta gamma-heterodimer, but not that of the G alpha i2-proteins, correlated with the inhibitory efficacy. The basal activity of the AC was reduced as well as the activation by some compounds. Eight days later (short-term withdrawal) both the levels of G alpha i2 and G beta gamma were elevated. Again, the inhibitory efficacy of the G-proteins correlated with the G beta gamma-heterodimer levels but not with those of the G alpha i2-protein. Furthermore, the changes of the G beta gamma-protein levels between the first and the eighth day correlated with the changes of the inhibiting efficacy. Only a trend was observed with respect to a lowered basal activity if compared with the intoxicated non-alcoholics. The activation of AC by guanylylimidyldiphosphate [Gpp(NH)p] and Gpp(NH)p + ethanol (200 mM in vitro) was still reduced. Observations after 3 and 6 months of abstinence demonstrated elevated G alpha i2- and G beta gamma-protein levels. This suggests residual marker properties of the G-proteins whereby the activity of AC was normal. Only the reduced stimulation by Gpp(NH)p + ethanol in vitro (200 mM), compared with the respective stimulation of AC of intoxicated non-alcoholics, suggested some residual disturbances of the signal transduction during long-term abstinence.