Transcriptome Analysis of Plasmodium falciparum Isolates From Benin Reveals Specific Gene Expression Associated With Cerebral Malaria.

Cerebral malaria (CM) is the severest form of Plasmodium falciparum infection. Children under 5 years old are those most vulnerable to CM, and they consequently have the highest risk of malaria-related death. Parasite-associated factors leading to CM are not yet fully elucidated. We therefore sought to characterize the gene expression profile associated with CM, using RNA sequencing data from 15 CM and 15 uncomplicated malaria isolates from Benin. Cerebral malaria parasites displayed reduced circulation times, possibly related to higher cytoadherence capacity. Consistent with the latter, we detected increased var genes abundance in CM isolates. Differential expression analyses showed that distinct transcriptome profiles are signatures of malaria severity. Genes involved in adhesion, excluding variant surface antigens, were dysregulated, supporting the idea of increased cytoadhesion capacity of CM parasites. Finally, we found dysregulated expression of genes in the entry into host pathway that may reflect greater erythrocyte invasion capacity of CM parasites.

[Sleeping Sickness: A Cause of False Positive HIV Rapid Diagnostic Tests]. / Maladie du Sommeil: Une Cause de Faux Positifs des Tests de Diagnostic Rapide du VIH.

Approaching the mechanisms related to false positives HIV rapid diagnostic tests (RDT) in patients with sleeping sickness may help to improve the accuracy of screening for HIV infection in areas endemic for Human African trypanosomiasis (HAT).We report on a patient from Congo who was managed like an AIDS-associated meningoencephalitis, based on a false positive HIV RDT at admission, and eventually received a diagnosis of sleeping sickness. A further retrospective cohort study performed in patients with HAT shows that most of positive HIV RDT obtained prior to treatment for sleeping sickness are false positives. We found that half of them were cleared at the end of treatment course, suggesting an early clearance of some antibodies involved in cross-reactivity.A substantial clearance of HIV RDT false positives occurs during therapy for HAT. In areas where Elisa HIV tests are not readily available, repeating the HIV RDT at the end of therapy may help to identify roughly half of false positives.

PfEMP1 A-Type ICAM-1-Binding Domains Are Not Associated with Cerebral Malaria in Beninese Children.

PfEMP1 is the major antigen involved in Plasmodium falciparum-infected erythrocyte sequestration in cerebrovascular endothelium. While some PfEMP1 domains have been associated with clinical phenotypes of malaria, formal associations between the expression of a specific domain and the adhesion properties of clinical isolates are limited. In this context, 73 cerebral malaria (CM) and 98 uncomplicated malaria (UM) Beninese children were recruited. We attempted to correlate the cytoadherence phenotype of Plasmodium falciparum isolates with the clinical presentation and the expression of specific PfEMP1 domains. Cytoadherence level on Hbec-5i and CHO-ICAM-1 cell lines and var genes expression were measured. We also investigated the prevalence of the ICAM-1-binding amino acid motif and dual receptor-binding domains, described as a potential determinant of cerebral malaria pathophysiology. We finally evaluated IgG levels against PfEMP1 recombinant domains (CIDRα1.4, DBLß3, and CIDRα1.4-DBLß3). CM isolates displayed higher cytoadherence levels on both cell lines, and we found a correlation between CIDRα1.4-DBLß1/3 domain expression and CHO-ICAM-1 cytoadherence level. Endothelial protein C receptor (EPCR)-binding domains were overexpressed in CM isolates compared to UM whereas no difference was found in ICAM-1-binding DBLß1/3 domain expression. Surprisingly, both CM and UM isolates expressed ICAM-1-binding motif and dual receptor-binding domains. There was no difference in IgG response against DBLß3 between CM and UM isolates expressing ICAM-1-binding DBLß1/3 domain. It raises questions about the role of this motif in CM pathophysiology, and further studies are needed, especially on the role of DBLß1/3 without the ICAM-1-binding motif.IMPORTANCE Cerebral malaria pathophysiology remains unknown despite extensive research. PfEMP1 proteins have been identified as the main Plasmodium antigen involved in cerebrovascular endothelium sequestration, but it is unclear which var gene domain is involved in Plasmodium cytoadhesion. EPCR binding is a major determinant of cerebral malaria whereas the ICAM-1-binding role is still questioned. Our study confirmed the EPCR-binding role in CM pathophysiology with a major overexpression of EPCR-binding domains in CM isolates. In contrast, ICAM-1-binding involvement appears less obvious with A-type ICAM-1-binding and dual receptor-binding domain expression in both CM and UM isolates. We did not find any variations in ICAM-1-binding motif sequences in CM compared to UM isolates. UM and CM patients infected with isolates expressing the ICAM-1-binding motif displayed similar IgG levels against DBLß3 recombinant protein. Our study raises interrogations about the role of these domains in CM physiopathology and questions their use in vaccine strategies against cerebral malaria.

Determinants of primary healthcare seeking behaviours for children during the first 18 months of life in Benin.

Background: Primary healthcare is a key element of management of childhood illness in Africa. The objectives were to identify primary care seeking determinants among infants and young children up to 18 mo in a birth cohort from Benin. Methods: From 2007 to 2009 in Benin, a birth cohort was followed until the age of 18 mo in three health centres. Multilevel Poisson regression models were fitted to identify the factors related to the monthly number of consultations. Maternal and newborn characteristics and infant general health parameters were considered. Results: A total of 566 children were followed. On average, 0.46 consultations per month per child were recorded. The number of consultations was significantly lower after the first 6 mo of life (p<0.001). A distance >1000 m was associated with fewer consultations (p=0.01). Primiparity was significantly associated with higher care seeking (relative risk 1.17 [95% CI 1.05 to 1.30], p<0.01). No child characteristics at birth were significantly associated with the number of consultations (all p>0.16). Conclusions: Development of health structures and improvement of access remain important goals for strengthening of the primary care health system. Studying factors of care seeking behaviour, like parity, can help to identify women more prone to seek care for their child during the first year of life.

Primary care physician management of tick bites in the Franche-Comté region (Eastern France, 2013).

INTRODUCTION: Tick bites, which may lead to Lyme disease, often prompt patients to consult their primary care physicians (PCPs). The aim of the present study was to assess how and how often PCPs in the Franche-Comté region of France manage tick bites. MATERIAL AND METHODS: Standardized questionnaires were sent to a random sample of 400 PCPs in the Franche-Comté region, requesting their voluntary and anonymous participation. The questionnaires collected socio-demographic details and practice-related information about tick-bite prophylaxis, Lyme serology, and tick-borne encephalitis vaccination. RESULTS: The crude response rate was 54.5% of the PCPs contacted. Tick-bite prophylaxis was prescribed as per current guidelines. However, Lyme serology seemed to be largely overprescribed for tick bites and in case of erythema migrans. A clear lack of knowledge about tick-borne encephalitis vaccination was also observed. DISCUSSION: PCPs provide the first line of care for patients presenting with tick bites. This study showed that although PCPs of the Franche-Comté region manage tick bites as per current guidelines, they need further training on Lyme serology limitations and availability of tick-borne encephalitis vaccination.

Paecilomyces variotii Fungemia in a Patient with Lymphoma Needing Liver Transplant.

Paecilomyces sp. are emerging pathogens in immunocompromised patients. We report here a case of Paecilomyces variotii fungemia, cured with amphotericin and anidulafungin, illustrating difficulties of early diagnosis and therapeutic choice in such rare fungal infection.

Antibiotics usage in infants during the first 18 months of life in Benin: a population-based cohort study.

Data centered on antibiotics usage and their determinants in African pediatric populations are limited. In order to define the determinants of antibiotics prescriptions (ABPr), we analyzed the data of a birth cohort in Benin. From 2007 to 2009, 538 infants were followed from birth to 18 months in three different health centers. The following determinants were assessed: infants' clinical findings at consultations, mothers' and children's characteristics at birth, and health parameters recorded at scheduled follow-up of general health parameters. Multilevel logistic models were performed for analysis. Among the 4394 consultations, fever represented 53.7 % of consultations, 64.1 % of which were non-malarial fevers. Antibiotics were prescribed during 44.2 % of the consultations and the proportion of ABPr differed significantly among health centers (p < 10(-3)). Nearly 40 % of ABPr were related to children without fever. During the first semester of life, the percentage of ABPr was twice lower than after (27.4 vs. 54.7, p < 10(-3)). Respiratory and enteric symptoms were positively associated with ABPr (p < 10(-3)). Malaria was significantly associated with a lower ABPr after the first semester [odds ratio (OR) = 0.55, 95 % confidence interval (CI) = 0.44-0.67, p < 10(-3)]. No maternal and child at-birth characteristics were associated with ABPr. ABPr was positively associated with a low breastfeeding score (p < 10(-3)). Studies on the rational use of antibiotics in this population should give priority to children more than 6 months of age, without malaria, and with respiratory and/or enteric symptoms. Our data also advocate for studies specifically designed to assess and improve healthcare providers' compliance to guidelines on antibiotics usage.

Compliance to recommendations for the management of curative treatment of Plasmodium vivax/ovale infections.

OBJECTIVES: We assessed the compliance to recommendations for the routine management of Plasmodium vivax/ovale malaria, and analyzed the impact of discrepancies on the quality of care. PATIENTS AND METHODS: We reviewed the cases of P. ovale and P. vivax malaria treated at the Besançon University Hospital, France (2008-2013). RESULTS: Chloroquine was prescribed in 44% of the 18 cases (4 due to P. ovale, 14 to P. vivax). Radical cure with primaquine was prescribed after the first bout of malaria for 6 patients. The primaquine dose prescribed was inferior to the recommended one for 4 patients. The mean delay between schizonticide treatment and primaquine cure was 43 days. CONCLUSIONS: The delay before access to primaquine radical cure was the only parameter, likely to alter treatment effectiveness, but also difficult to shorten. Future national guidelines should take into account that not all patients have access to primaquine treatment immediately after schizonticide treatment.

Leptospirosis in Franche-Comté (FRANCE): clinical, biological, and therapeutic data.

OBJECTIVES AND METHOD: We report the patient data in 77 cases of leptospirosis confirmed by PCR and/or serology (micro-agglutination), observed between 1994 and 2008 at the Besançon teaching hospital. Our aim was to compare the epidemiological, clinical, biological, and therapeutic characteristics of leptospirosis in the Franche-Comté region, to those reported in other regions. RESULTS: The median age was 42years and 95% were male patients. Leptospirosis acquisition was likely related to aquatic leisure activities (50.6%), professional exposure (28.6%), building maintenance works (11.7%), or unknown (9.1%). Forty-eight cases were uncomplicated and 29 were severe presentations of leptospirosis. Among severe cases, eight patients had to be managed in an intensive care unit, and one patient died. L. grippotyphosa and L. icterohaemorrhagiae were the main serogroups involved. Age above 50years and serogroup L. icterohaemorrhagiae were positively associated with clinical severity. The outcome was favorable for 15 patients treated with ceftriaxone for less than 7days. CONCLUSIONS: We recommended conducting clinical trials aiming at validating short courses of ceftriaxone to treat leptospirosis.

Typhoidal tularemia: 2 familial cases.

Eastern France was not known as a region endemic for tularemia until year 2006. We report on 2 cases of typhoidal tularemia in Eastern France, a 43-year-old hospitalized woman and her husband. Diagnosis was established after fever clearance on serodiagnosis criteria. The source of infection is unclear. As persons in the same family may likely be exposed to a common zoonotic source of infection, tularemia should be considered in the etiologies of familial fever epidemics.

[Treatment of pediatric malaria in Africa: act at issue]. / Traitement du paludisme de l'enfant en Afrique: les act en question.

Artemisinin-based combination therapies (ACT) have been proposed as alternatives to currently used antimalarials and are poised large-scale deployment in Africa. These combinations are particularly attractive for managing malaria in children. Expected benefits of ACT include enhanced efficacy, rapid action, stabilized antimalarial resistance growth and lower malaria transmission. This article discusses what can be reasonably expected of ACT in an African setting with emphasis on patient comfort.

Traitement du paludisme de l'enfant en Afrique : les ACT en question

Les Artemisinin-based Combination Therapies (ACT) representent la majorite des alternatives aux antipaludiques de reference et sont sur le point d'etre deployees largement en Afrique. Elles sont particulierement attractives pour traiter les enfants. Les vertus annoncees de ces associations sont multiples : puissance accrue; rapidite d'action; stabilisation de la chimioresistance et reduction de la transmission. L'abondante litterature consacree aux ACT depuis quelques annees permet de faire le point sur ces divers aspects; en insistant sur la question du confort des enfants malades

[Predictive factors of virological response to primary antiretroviral treatment]. / Facteurs prédictifs de la réponse virologique à un premier traitement antirétroviral.

OBJECTIVES: During 1999, first-line antiretroviral combinations for the treatment of HIV infections have diversified. The aim of our study was two-fold: define the factors associated with initial success and define the factors associated with virological rebound in patients in whom a primary antiretroviral therapy (ARV) had been initiated between 1999 and 2000. METHOD: We conducted a retrospective multicenter study regrouping 6 HIV clinics in the North-East of France. Data were Issued from the patients medical files. Primary success was defined as plasma HIV RNA viral load (VL<200 copies/ml within 6 Months of therapy and two consecutive VL<200 copies/ml. Virological rebound was defined as two consecutive VL>1000 copies/ml after primary success. Predictors of success were determined using multivariate logistic regression and SAS 8.2 software. RESULTS: Analysis concerned 123 patients, with 19% stage C when ARV was initiated. Their median CD4 and PVL values at baseline were 233/mm3 and 73,000 copies/ml respectively. The median duration of follow-up was of 20.7 Months [(mean (STD): 20.6 (6.7)]. Initial treatments were distributed as follows: 2 NRTI + 1NNRTI, n=66 (54%); 2 NRTI+1PI, n=44 (36%); 3 NRTI, n=13 (10%). Primary success was obtained in 100 (81,3%) patients. Among these, 6 (6%) developed secondary virologic failure. The absence of change in initial ARV treatment within first 4 Months, and good compliance to treatment were statistically associated with primary success in univariate (p values respectively: 0.004 and 0.04) and in multivariate analysis (p respectively: 0.009 and 0.03). The proportion of failure was higher in the patients with lower baseline CD4 levels lesser than 200/mm3 (p=0.09). CONCLUSION: In this cohort of patients, tolerance and compliance to the first regimen were associated to primary success. These results emphasize the role of compliance in primary success and reinforces need to work on compliance in such patients.

Amodiaquine-artesunate versus amodiaquine for uncomplicated Plasmodium falciparum malaria in African children: a randomised, multicentre trial.

BACKGROUND: Increasing drug resistance limits the choice of efficacious chemotherapy against Plasmodium falciparum malaria in Africa. Amodiaquine still retains efficacy against P falciparum in many African countries. We assessed the safety, treatment efficacy, and effect on gametocyte carriage of adding artesunate to amodiaquine in three randomised trials in Kenya, Sénégal, and Gabon. METHODS: We enrolled 941 children (400 in Kenya, 321 in Sénégal, and 220 in Gabon) who were 10 years or older and who had uncomplicated P falciparum malaria. Patients were randomly assigned amodiaquine (10 mg/kg per day for 3 days) plus artesunate (4 mg/kg per day for 3 days) or amodiaquine (as above) and placebo (for 3 days). The primary endpoints were parasitological cure rates at days 14 and 28. Analysis was by intention to treat and by an evaluability method. FINDINGS: Both regimens were well tolerated. Six patients in the amodiaquine-artesunate group and five in the amodiaquine group developed early, drug-induced vomiting, necessitating alternative treatment. By intention-to-treat analysis, the day-14 cure rates for amodiaquine-artesunate versus amodiaquine were: 175/192 (91%) versus 140/188 (74%) in Kenya (D=16.7% [95% CI 9.3-24.1], p<0.0001), 148/160 (93%) versus 147/157 (94%) in Sénégal (-1.1% [-6.7 to 4.5], p=0.7), and 92/94 (98%) versus 86/96 (90%) in Gabon (8.3% [1.5-15.1], p=0.02). The corresponding rates for day 28 were: 123/180 (68%) versus 75/183 (41%) in Kenya (27.3% [17.5-37.2], p<0.0001), 130/159 (82%) versus 123/156 (79%) in Sénégal (2.9% [-5.9 to 11.7], p=0.5), and 80/94 (85%) versus 70/98 (71%) in Gabon (13.7% [2.2-25.2], p=0.02). Similar rates were obtained by evaluability analysis. INTERPRETATION: The combination of artesunate and amodiaquine improved treatment efficacy in Gabon and Kenya, and was equivalent in Sénégal. Amodiaquine-artesunate is a potential combination for use in Africa. Further investigations to assess the potential effect on the evolution of drug resistance, disease transmission, and safety of amodiaquine-artesunate are warranted.

Comparison of methods for the rapid laboratory assessment of children with malaria.

Rapid diagnosis and accurate quantification of Plasmodium falciparum parasitemia are important for the management of malaria. The assessment of disease severity also depends on evaluation of metabolic indexes such as blood glucose and lactate concentrations. Here we describe an accurate and rapid alternative to conventional thick film examination (Lambaréné method). We also assess near-patient methods for measuring blood glucose (OneTouch) and lactate (Accusport). The accuracy of the Lambaréné method is similar to that of thin films. Results from the OneTouch glucose meter also are in good agreement with a YSI 2300 reference meter. Overall, the Accusport lactate meter agrees poorly with the YSI 2300 reference meter. However, the sensitivity and specificity to detect hyperlactatemia (blood lactate > or = 5 mmol/L) are 0.94 and 0.98, respectively.

Artesunate and praziquantel for the treatment of Schistosoma haematobium infections: a double-blind, randomized, placebo-controlled study.

Recently, artemisinin derivatives have been shown to be efficacious in chemoprophylaxis of and chemotherapy for Schistosoma japonicum and S. mansoni infections. Therefore, a double-blind, randomized, placebo-controlled study was carried out to investigate the efficacy and tolerability of artesunate plus placebo and the combination of artesunate and praziquantel in the treatment of S. haematobium infections in Gabon. The 300 infected schoolchildren included in the study were randomized to receive artesunate plus placebo (n=90), praziquantel plus placebo (n=90), artesunate and praziquantel (n=90), or only placebo (n=30). End points were efficacy, assessed as cure on day 56, and tolerability. All treatment regimens were well tolerated. The praziquantel plus placebo-treated group attained a cure rate of 73%, artesunate plus placebo a rate of 27%, the combination of artesunate and praziquantel a rate of 81%, and placebo alone a rate of 20%. In summary, earlier findings of efficacy of artemisinin derivitives against S. mansoni and S. japonicum could not be confirmed in S. haematobium infections.

Plasmodium falciparum liver-stage antigen-1 peptide-specific interferon-gamma responses are not suppressed during uncomplicated malaria in African children.

Liver-stage antigen (LSA)-1 is a candidate vaccine molecule for Plasmodium falciparum malaria, but knowledge of the evolution of naturally acquired immune responses to LSA-1 in African children is lacking. We therefore assessed cellular immune responses to two defined T cell epitopes of LSA-1, during and after uncomplicated P. falciparum malaria in a group of Gabonese children. In terms of their prevalence, interferon (IFN)-gamma responses of peripheral blood mononuclear cells (PBMC) to an LSA-1 N-terminal peptide, T1, were significantly higher when measured during the acute phase compared with convalescence. IFN-gamma responses to the LSA-J (hinge region) peptide showed a similar profile, but at a lower prevalence. Depletion experiments confirmed that CD8+ T cells are a major source of peptide-driven IFN-gamma, but both lymphoproliferation and the production of IL-10 in response to either of the peptides was low in all children at all times. PBMC from 25% of the children failed to produce IFN-gamma in response to either peptide at any time-point. The results suggest that lymphocytes producing IFN-gamma in response to at least one T cell epitope of LSA-1 are most frequent in the peripheral circulation during the acute phase of P. falciparum malaria. Thus, in this case, the generalised suppression of cell-mediated responses which characterises acute malaria does not affect liver-stage antigen-specific IFN-gamma production. These findings imply that measurements of the frequency of parasite antigen-specific cellular immune responses in clinically healthy individuals may represent significant underestimations, which has important implications for the design of field-based vaccine antigen-related studies.