PRRT2 mutations and paroxysmal disorders.

In the past year, mutations in the PRRT2 gene have been identified in patients with paroxysmal kinesigenic dyskinesia and other paroxysmal disorders. We conducted a review of the literature on PRRT2 mutation-associated disorders. Our objectives were to describe the wide clinical spectrum associated with PRRT2 mutations, and to present the current hypotheses on the underlying pathophysiology. PRRT2 mutations are associated with a wide range of clinical syndromes: the various paroxysmal dyskinesias, infantile seizures, paroxysmal torticollis, migraine, hemiplegic migraine, episodic ataxia and even intellectual disability in the homozygous state. The PRRT2 protein, through its interaction with SNAP-25, could play a role in synaptic regulation in the cortex and the basal ganglia. The pathogenesis may be caused by PRRT2 loss of function, which may induce synaptic deregulation and neuronal hyperexcitability. However, this does not explain the phenotypic variability, which is likely modulated by environmental factors, modifier genes or age-dependent expression. The clinical spectrum of PRRT2 mutations has expanded among paroxysmal disorders and beyond. Unraveling the molecular pathways linking the genetic defect to its clinical expression will be crucial for the diagnosis and treatment of these disorders.

Frequency of cytokine-producing T cells in HIV-infected patients treated with stavudine, didanosine, and ritonavir.

To assess prospectively the influence of the control of viral replication on the frequency of cytokine-producing T cells, and to correlate these changes with immune activation, we conducted a 15-month follow-up study of IFN-gamma- and IL-2-producing CD4+ and CD8+ T cells at a single-cell level in 12 previously untreated patients receiving highly active antiretroviral therapy (HAART). At baseline we observed a strikingly high proportion of IFN-gamma-producing CD8+ T cells. The treatment-induced decrease in the proportion of IFN-gamma-producing CD8+ T cells ran parallel to the decrease in HLA-DR+ and CD38+CD8+ T cell subsets and was associated with the reduction in HIV RNA level. IL-2-producing cells were mainly CD4+. As a consequence of CD4+ T cell loss, the number of IL-2-producing CD4+ T cells was lower in patients than in control subjects (52 vs. 171 cells/microl), but the proportion of these cells was unchanged (22.4 vs. 19.3). During therapy the proportion of CD4+ IL-2-producing cells was initially stable and then fell markedly at month 5, followed by a gradual return to previous values. The reduction in viral load was associated with the fall in the proportion of CD4+ activated subsets. Intracellular cytokine assays are a new approach to the assessment of T cell function in HIV infection. Our results suggest that the functional capacity of CD4+ T cells is probably less severely altered than previously thought on the basis of conventional assays. CD8+ T cells exhibit an increased capacity to produce IFN-gamma that is associated with an increase in activation marker expression. These alterations decrease partially and in parallel under treatment.

Predictors of short- and long-term survival in HIV-infected patients admitted to the ICU.

STUDY OBJECTIVES: To evaluate the prognosis of HIV-infected patients admitted to ICUs and to identify factors predictive of short- and long-term survival. DESIGN: A prospective study from January 1, 1990, to December 31, 1992, including all consecutive HIV-infected patients admitted to our ICU for the first time. ICU survivors were followed up until January 1, 1994. SETTING: An 18-bed infectious diseases ICU in a 1,300-bed university hospital in Paris. PATIENTS: Four hundred twenty-one HIV-related admissions were recorded during the study period (33.5% of 1,258 admissions to ICU); 354 HIV-infected patients were first ICU admissions and were analyzed. MEASUREMENTS AND RESULTS: Predictive factors on univariate and multivariate analyses (logistic regression and Cox model) for short- and long-term mortality were performed. Respiratory failure was the main cause of admission (49.2%), followed by neurologic disorders (26.8%), sepsis (10.2%), heart failure (4.5%), and miscellaneous disorders (9.3%). For these groups, in-ICU and in-hospital mortality rates were as follows: 16.7% and 33.9%; 23.2% and 41.1%; 38.9% and 58.3%; 25% and 68.8%; and 12.1% and 24.2%, respectively. In-ICU and in-hospital mortality rates were significantly different across the groups (p=0.026 and 0.002, respectively). Multivariate analysis showed that the in-hospital outcome was significantly associated with functional status (p=0.05), time since AIDS diagnosis (p=0.04), HIV disease stage (0.016), simplified acute physiology score (SAPS I) (p=0.06), need for mechanical ventilation (p<0.000001), and its duration (p=0.0001). In the 281 patients who were discharged alive from the ICU, cumulative survival rates were 51%+/-38% at 6 months, 28%+/-38% at 12 months, and 18%+/-30% at 24 months. Median and crude mean+/-SD survival times were 199 days and 316+/-343 days. Multivariate analysis showed that the long-term outcome was significantly associated with functional status (p=0.000001), weight loss (p=0.00001), the CD4 count (p=0.00001), the HIV disease stage (p=0.01), the duration of AIDS (p=0.001), the admission cause group (p=0.03), and the SAPS I at admission (p=0.00001). CONCLUSIONS: The short-term (in-ICU and in-hospital) outcome of HIV-infected patients was mainly related to the severity of the acute illness (SAPS I, cause of admission, need for and duration of mechanical ventilation), and to the preadmission health status, based on functional status and weight loss. Some of these parameters, in particular the SAPS I and preadmission health status, also influenced the long-term outcome. Whereas HIV-related variables had little impact on the in-ICU outcome, they were closely related with the in-hospital outcome and even more strikingly with the long-term outcome. Thus, the life expectancy of HIV-infected patients, which depends primarily on the natural history of the HIV infection, is the most powerful determinant of the long-term prognosis. Our results confirm that ICU support for HIV-infected patients should not be considered futile.

Evaluation of high-dose regimen of paromomycin against cryptosporidiosis in the dexamethasone-treated rat model.

In the dexamethasone-treated rat model of cryptosporidiosis, paromomycin was effective at a dosage of 50 mg/kg/day or more for ileal infection and 200 mg/kg/day or more for cecal infection. At 1 and 3 weeks after treatment, a persistent infection was demonstrated in all rats. These results confirm the anticryptosporidial activity of paromomycin and underscore the limitations of this compound because of its potential toxicity at such high dosages and its inability to eradicate the infection.

Reevaluation of the relative risk for susceptibility to celiac disease of HLA-DRB1, -DQA1, -DQB1, -DPB1, and -TAP2 alleles in a French population.

In a population of 46 children with CD recruited in the Paris area of France, an excess of DRB1*03 and DRB1*07 alleles and of DR3/DR7, DR3/DR3 and DR11(or 12)/DR7 phenotypes was found (RRs of 6.3, 9.3, 24.6, 15, and 15.1, respectively), which is reminiscent of the markers of susceptibility observed in southern rather than in northern European celiac patients. More importantly, the highest association with CD was not found in individuals expressing the DQA1*0501-DQB1*0201 heterodimer in single dosage (RR = 24.9) or in homozygous state, but in people co-expressing one copy of DQA1*0501-DQB1*0201 on one haplotype and a second copy of DQB1*0201 on the second haplotype (RR = 35.7). This suggests that in our population either DQB1*0201 or a gene closely linked to DQB1*0201 influences the susceptibility to CD conferred by the DQA1*0501-DQB1*0201 heterodimer. Significant positive or negative RRs conferred by some TAP2 or DPB1 alleles were found. However, they were moderate compared to the RR conferred by the expression of a second copy of DQB1*0201. Moreover, they were no longer significant when patients were compared with HLA-DR matched controls. This suggests that associations of CD with TAP2 and DPB1 alleles are secondary to linkage disequilibria and argues against the contribution of these alleles in resistance and/or susceptibility to CD. Thus the "raison d'être" of a "DQB1*0201 second haplotype effect" in susceptibility to CD remains to be elucidated.

The pharmacokinetics of chloroquine in healthy and Plasmodium chabaudi-infected mice: implications for chronotherapy.

The schizogony of malarial parasite is a typical cyclic phenomenon where the different stages of parasite development appear at regular time intervals. Each of the stages is specifically sensitive to different antimalarial drugs. Knowledge of the details of the cycle, drug susceptibility and the pharmacokinetics of drugs, could allow the improvement of drug action by the chronotherapeutic approach: treatment at the time of appearance of the drug sensitive stage with a drug that displays rapid pharmacokinetics. Since murine malarias serve as preferable models for in vivo drug testing, the pharmacokinetics of subcutaneously (sc) administered chloroquine (CQ) were tested in the whole blood of healthy mice and in animals slightly (1.5-3.5% parasitemia) or heavily infected (21-25% parasitemia) with Plasmodium chabaudi chabaudi. The half-time of absorption was around 5 min and almost independent of parasitemia. The apparent half-time of drug concentration decay was around 40 min in healthy animals, about 90 min at low parasitemia and about 410 min in heavy infection, indicating that the concentration of CQ is a typical spike, that is prolonged by asymptomatic disease, and considerably more by the active accumulation of CQ in infected cells. The latter is confirmed by the 3-fold higher peak blood [CQ] at the trophozoite stage and < 1.5-fold increase during schizogony. In conjunction with our previous experiments which showed that a single sc injection of 5 mg/kg CQ is sufficient to eliminate the drug susceptible mid-term trophozoite stage, the present results seem to justify to propose the chronotherapeutic approach for the treatment of malaria.

Demographic factors associated with HTLV-1 infection in a Gabonese community.

An epidemiological study of human T-lymphotropic virus type 1 (HTLV-1) and syphilis has been carried out in a multiethnic community of seven neighbouring villages located in eastern Gabon on 1240 subjects over 5 years old (82.7% of the population in this age range). Antibodies to HTLV-1 (anti-HTLV-1) were detected by ELISA with confirmation by Western Blot and antibodies to syphilis by Venereal Diseases Research Laboratory assay with confirmation by the Treponema pallidum haemaglutination assay. The prevalence rate of anti-HTLV-1 was 8.5% and increased from 3.7% in the 5-14 years age group to 23.8% in the over 60 years age group. Logistic regression showed that the positivity for anti-HTLV-1 was associated with age, ethnic group and sex (higher prevalence in females). The seroprevalence rate of syphilis was 8.2%. Seropositivity for syphilis and HTLV-1 were related but age was a confounding variable in this relationship. This study showing a highly heterogeneous distribution of HTLV-1 in a geographically limited area suggests the role of environmental and behavioural factors in HTLV-1 transmission.

Evaluation of curative anticryptosporidial activity of paromomycin in a dexamethasone-treated rat model.

A dexamethasone-treated rat model of cryptosporidiosis was used to evaluate the curative activity of paromomycin. Although eradication of the parasite could not be demonstrated, statistically significant decreases in oocyst excretion and in the intensity of ileal parasitism were observed in animals receiving 100 mg of paromomycin per kg of body weight per day.

[Epidemiologic interrelation among intestinal protozoans by direct count. Statistical analysis of 9,471 examinations and a comparison with the literature]. / Interrelations épidémiologiques entre protozoaires intestinaux a contage direct. Analyse statistique de 9,471 examens et comparaison avec la littérature.

A statistical study of the results of coprological analysis allows us to appreciate the prevalence of the different parasites, depending on the geographic origin of the outpatients of a hospital situated in the suburbs of Paris. The multifactorial analysis shows, besides other problems, the epidemiological relations between these parasites or, in the contrary, the oppositions which can appear. These results are compared with those published since two decades; their study empowers to set the problem of the fiability of some statistics and, therefore, of the possibilities of an efficient epidemiological research.

Population-based study of serum hepatitis B virus DNA in Gabon.

The prevalence of serum hepatitis B virus (HBV) deoxyribonucleic acid (DNA) was measured in a Gabonese community at high risk for HBV infection. Among 698 subjects 5 to 24 years old, the prevalence of HBsAg was 11.1% vs. 57.9% for anti-HBs and 7.2% for anti-HBc alone. The prevalence of HBeAg among HBsAg-positive subjects was 26.5% vs. 59.5% for anti-HBe. The prevalence of HBV DNA tested by a hybridization spot test was 2.1% in the overall population and 18.7% among HBsAg-positive subjects. HBV DNA was found in 15 of 21 HBeAg-positive subjects but in none of the subjects positive for anti-HBe or negative for both HBeAg and anti-HBe. HBV DNA was not detected in any HBsAg negative subjects. The prevalence of HBV DNA decreased with age. This low prevalence of HBV DNA contrasts with the high level of endemicity in the study population.

Dapsone-pyrimethamine compared with aerosolized pentamidine as primary prophylaxis against Pneumocystis carinii pneumonia and toxoplasmosis in HIV infection. The PRIO Study Group.

BACKGROUND: Pneumocystis carinii pneumonia and toxoplasmic encephalitis are frequent life-threatening opportunistic infections in patients with human immunodeficiency virus (HIV) infection. Primary prophylaxis against P. carinii pneumonia is now common, but there are few data on regimens for primary prophylaxis against toxoplasmosis. METHODS: We conducted a randomized trial that compared two prophylactic regimens: dapsone (50 mg per day) plus pyrimethamine (50 mg per week) was compared with aerosolized pentamidine (300 mg per month). The patients had symptomatic HIV infection, no history of P. carinii pneumonia or symptomatic toxoplasmosis, and CD4+ counts below 200 per cubic millimeter (0.2 x 10(9) per liter). RESULTS: In an intention-to-treat analysis, after a median follow-up of 539 days P. carinii pneumonia developed in 10 patients in each group, whereas toxoplasmosis developed in 32 of 176 patients in the pentamidine group and 19 of 173 patients in the dapsone-pyrimethamine group. Those assigned to pentamidine had a risk of P. carinii pneumonia that was similar to the risk in those assigned to dapsone-pyrimethamine (adjusted relative risk, 1.13; 95 percent confidence interval, 0.44 to 2.92; P = 0.79), but a higher risk of toxoplasmosis (adjusted relative risk, 1.81; 95 percent confidence interval, 1.12 to 2.94; P = 0.02). Among the 262 patients with serologic evidence of past exposure to Toxoplasma gondii, the relative risk of symptomatic toxoplasmosis was 2.37 times higher in those assigned to pentamidine (95 percent confidence interval, 1.3 to 4.4; P = 0.006). More patients discontinued dapsone-pyrimethamine than pentamidine because of toxicity (42 vs. 3; P < 0.001). Survival was similar in the two groups. CONCLUSIONS: For primary prevention of P. carinii pneumonia, dapsone-pyrimethamine is as effective, though not as well tolerated, as aerosolized pentamidine. Dapsone-pyrimethamine also prevents first episodes of toxoplasmosis.

Efficacy of intramuscular amopyroquin for treatment of Plasmodium falciparum malaria in the Gabon Republic.

The efficacy of a 12-mg/kg (of body weight) intramuscular amopyroquin (ApQ) regimen (two successive 6-mg/kg injections at a 24-h interval), previously established from kinetic studies on healthy volunteers and multicenter studies on patients with malaria, was investigated in 152 patients (children and adults) in Gabon with Plasmodium falciparum malaria. All children in the present study (ages, 1 to 14 years) showed higher degrees of parasitemia and temperatures and lower hematocrit values than did adults at the time of admission. No major side effects in the patients were observed. On day 7, all patients were apyretic; clearance of parasites was obtained in 143 of 152 patients (94%); a low level of parasitemia was observed in nine patients, all of whom were children (6%). In vitro chemosusceptibility tests carried out on P. falciparum isolates from patients demonstrated 51% of resistance to chloroquine (Cq). A correlation was found between the in vitro chemosusceptibilities to Cq and ApQ, but no relationship between the in vitro activity and the in vivo efficacy of ApQ could be found. Concentrations of ApQ in blood assayed by high-performance liquid chromatography on day 2 did not differ significantly between the groups in whom therapy was a success or a failure, although the mean ApQ concentration in blood for the group that failed therapy was 31% lower. Concentrations greater than 100 nmol of self-prescribed Cq and amodiaquine per liter, which were assayed simultaneously with ApQ, were observed in 78 patients (51%). They did not correlate with degrees of parasitemia compared with ApQ alone, which did. Successful treatment by day 7 was obtained in 69 of 74 patients (93%) who had no other 4-aminoquinolines in their blood. The results of the present study show that an ApQ regimen of 12 mg/kg over 2 days may be an alternative for the treatment of Cq-resistant malaria, at least in adult patients, in the field.

Is steroid dependent Crohn's disease a separate entity?

Crohn's disease has been sometimes considered as a syndrome including different entities. In this prospect we tried to assess whether steroid dependent Crohn's disease could be a separate sub-group. Eighty five patients (mean follow-up: 6 years) with documented Crohn's disease were classified into 3 groups: 1--patients never treated with steroids (NS) (N = 37); 2--patients in whom steroids had been given but had been withdrawn (NSD) (N = 37); 3--patients dependent on continuous steroid therapy (SD) (N = 11). Ten variables were considered: age at onset, sex, CDAI, cumulative topography of lesions, extra-intestinal symptoms, albuminemia, ESR, surgical operations, annual frequency of relapses. Monofactorial analysis (analysis of variance and CHI2 test) showed group SD to be significantly different from group NS and in term of age at onset, CDAI, ESR, annual frequency of relapses, extra-intestinal symptoms, surgical operations. In contrast, a multivariate analysis of correspondences applied to the 3 groups and to 9 dichotomous variables showed that group SD is not a separate entity, but the limit of a continuum extending from group NS to group NSD. This was ascertained by a CHI2 test applied to the dichotomous variables. Thus, within the limits of this study Crohn's disease appears to be a homogeneous entity rather than a heterogeneous syndrome.

Echotomographic and serological population-based study of hydatidosis in central Tunisia.

A population-based echotomographic (ECT) and serological survey of hydatidosis was carried out in a high risk community located in Central Tunisia. 1434 subjects over 5 years of age (93.3% of the population in this age range) underwent an abdominal echotomography (ECT) and a serological test (ELISA with confirmation by counterelectrophoresis). The ECT prevalence rate was 3.5% and increased with age reaching 7.7% in the over 39 years age group. Most subjects (96.0%) had liver cyst(s). The serological prevalence rate was 2.9%. A strong agreement was found between ECT and serological results (Kappa test = 0.449). Taking ECT as a reference, the relative specificity and sensitivity of serology were 99.3 and 62.0 respectively. Most ECT positive seronegative subjects had calcified cysts. These results confirm the presence of highly endemic foci of hydatidosis in Central Tunisia, show a good agreement between serological and ECT results at a population level and demonstrate the high feasibility of ECT as a screening technique.

Assessment of the protective value of antibodies to the Plasmodium falciparum ring-infected erythrocyte surface antigen (RESA): an epidemiologic study in Madagascar.

The ring-infected erythrocyte surface antigen (RESA), a Plasmodium falciparum merozoite antigen, is a major vaccine candidate against falciparum malaria. To investigate the protective role of antibodies to RESA and its 4-mer, 8-mer, and 11-mer repeated amino acid sequences under conditions of natural exposure, a case-control and a cohort study were carried out in 1988 in a rural community in Madagascar where malaria reappeared recently. Fifty cases with greater than 1,000 P. falciparum per microliter of blood, and 45 controls with a negative blood smear were enrolled and sera were collected. Forty-one controls were followed for 20 weeks to identify malarial attacks. Protection against clinical malaria was assessed by the absence of malarial attacks requiring therapy. At enrollment, positivity rates and reactivity levels to RESA or repeats were similar in cases and controls. The 11-mer repeat antibody level was higher in the 26 controls who experienced at least one malarial attack during follow-up than in the 15 other controls (p less than 0.01). Thus, antibodies to the 11-mer repeat were predictors of the subsequent appearance of the disease. After adjustment for antibodies to the 11-mer repeat, antibodies to whole RESA had a negative predictive value on the occurrence of malarial attacks (p = 0.04). Different epitopes within the RESA molecule may elicit production of antibodies with different activities.

[Epidemiology of HTLV-I infection in its hyperendemic foci (Japan, tropical Africa, Caribbean)]. / Epidémiologie de l'infection par HTLV-I dans ses foyers d'hyperendémie (Japon, Afrique intertropicale, Caraïbes).

HTLV-1 infection is endemic in Japan, black Africa, the Caribbean and several regions of South America. In these foci, the infections is very heterogeneously distributed (variations from village to village, intrafamilial clustering). The virus is transmitted from mother to child, and breast feedings seems to play a major role. Sexual transmission is usually from man to woman. The frequency of transmission by blood transfusion must not be underestimated. It justifies the systematic detection of HTLV-1 infection in areas where it is economically feasible.

[A fosfomycin-gentamicin combination in the treatment of experimental endocarditis caused by Klebsiella pneumoniae producing type TEM-3 beta-lactamase]. / Association fosfomycine-gentamicine dans le traitement d'une endocardite expérimentale à Klebsiella pneumoniae produisant une beta-lactamase de type TEM-3.

The authors studied the activity of fosfomycin (FOS) and/or gentamicin (GEN) against a Klebsiella pneumoniae strain resistant to all beta-lactams--except cephamycins and imipenem--by production of a plasmid mediated extended broad-spectrum beta-lactamase-TEM-3, to all aminoglycosides--except gentamicin--by production of a plasmid mediated 6' aminoglycoside acetyltransferase IV, to sulfonamides and to tetracyclines. In vitro, the combination FOS (MIC = MBC = 32 mg/l) + GEN (MIC = MBC = 2) appeared indifferent (FIC = 0.75; FBC = 1). In vivo, on experimental endocarditis in rabbits, FOS alone was ineffective, GEN alone was active but only at high dose regimen, FOS - GEN combination was active as compared with controls. Fosfomycin - gentamicin combination may be an alternative in the therapy of severe infections due to multiresistant Enterobacteriacae.

Prevention of Pneumocystis carinii pneumonia relapse by pentamidine aerosol in zidovudine-treated AIDS patients.

To examine the efficacy and tolerance of pentamidine aerosol in the prevention of Pneumocystis carinii pneumonia (PCP) relapse in patients with the acquired immunodeficiency syndrome (AIDS) being treated with zidovudine, 51 patients who had had an episode of PCP in the previous 5 months were enrolled in a randomised controlled study. 25 patients (group I) received pentamidine mesylate aerosol (4 mg/kg every 2 weeks for the first month then monthly) and zidovudine, and 26 patients (group II) zidovudine alone. 3 group I patients withdrew from pentamidine therapy prematurely and were excluded from the analysis of efficacy. Relapses of PCP occurred in 2 out of 22 (9%) group I patients and in 16 out of 26 (61%) group II patients after a mean follow-up of 10 and 8.7 months, respectively. The two groups differed significantly (p less than 0.0001) in proportions without relapse. They did not differ in proportions surviving. Bronchial intolerance was common (47%); no systemic side-effects of pentamidine were observed. Pentamidine aerosol thus seems to be effective in preventing PCP relapses in AIDS patients on zidovudine. The early termination of the trial prevented assessment of the long-term efficacy and safety of pentamidine given by aerosol.