Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Painful vaso-occlusive crisis, a hallmark of sickle cell anaemia, results from complex, incompletely understood mechanisms. Red blood cell (RBC) damage caused by continuous endogenous and exogenous oxidative stress may precipitate the occurrence of vaso-occlusive crises. In order to gain insight into the relevance of oxidative stress in vaso-occlusive crisis occurrence, we prospectively compared the expression levels of various oxidative markers in 32 adults with sickle cell anaemia during vaso-occlusive crisis and steady-state conditions. Compared to steady-state condition, plasma levels of free haem, advanced oxidation protein products and myeloperoxidase, RBC caspase-3 activity, as well as the concentrations of total, neutrophil- and RBC-derived microparticles were increased during vaso-occlusive crises, whereas the reduced glutathione content was decreased in RBCs. In addition, natural anti-band 3 autoantibodies levels decreased during crisis and were negatively correlated with the rise in plasma advanced oxidation protein products and RBC caspase-3 activity. These data showed an exacerbation of the oxidative stress during vaso-occlusive crises in sickle cell anaemia patients and strongly suggest that the higher concentration of harmful circulating RBC-derived microparticles and the reduced anti-band 3 autoantibodies levels may be both related to the recruitment of oxidized band 3 into membrane aggregates.
ISSN: 0007-1048

hal-01668325
https://hal.univ-antilles.fr/hal-01668325
DOI : 10.1111/bjh.14476

Éditeur(s) : HAL CCSD American Society of Hematology
Résumé : International audience
Human immunodeficiency virus (HIV)-associated disseminated Histoplasma capsulatum capsulatum infection often mimics tuberculosis. This disease is well know in the United States but is dramatically underdiagnosed in Central and South America. In the Amazon region, given the available incidence data and the regional HIV prevalence, it is expected that, every year, 1,500 cases of histoplasmosis affect HIV patients in that region alone. Given the mortality in undiagnosed patients, at least 600 patients would be expected to die from an undiagnosed but treatable disease. The lack of a simple diagnostic tool and the lack of awareness by clinicians spiral in a vicious cycle and made a major problem invisible for 30 years. The HIV/acquired immunodeficiency syndrome community should tackle this problem now to prevent numerous avoidable deaths from HIV-associated histoplasmosis in the region and elsewhere.
ISSN: 0006-4971

inserm-00913874
http://www.hal.inserm.fr/inserm-00913874
http://www.hal.inserm.fr/inserm-00913874/document
http://www.hal.inserm.fr/inserm-00913874/file/2013_Nacher_-_How_many_have_died_from_undiagnosed_histoplasmosis.pdf
DOI : 10.4269/ajtmh.13-0226

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Leg ulcer is a disabling complication in patients with sickle cell anemia (SCA) but the exact pathophysiological mechanisms are unknown. The aim of this study was to identify the hematological and hemorheological alterations associated with recurrent leg ulcers. Sixty-two SCA patients who never experienced leg ulcers (ULC-) and 13 SCA patients with a positive history of recurrent leg ulcers (ULC+) - but with no leg ulcers at the time of the study - were recruited. All patients were in steady state condition. Blood was sampled to perform hematological, biochemical (hemolytic markers) and hemorheological analyses (blood viscosity, red blood cell deformability and aggregation properties). The hematocrit-to-viscosity ratio (HVR), which reflects the red blood cell oxygen transport efficiency, was calculated for each subject. Patients from the ULC+ group were older than patients from the ULC- group. Anemia (red blood cell count, hematocrit and hemoglobin levels) was more pronounced in the ULC+ group. Lactate dehydrogenase level was higher in the ULC+ group than in the ULC- group. Neither blood viscosity, nor RBC aggregation properties differed between the two groups. HVR was lower and RBC deformability tended to be reduced in the ULC+ group. Our study confirmed increased hemolytic rate and anemia in SCA patients with leg ulcers recurrence. Furthermore, our data suggest that although systemic blood viscosity is not a major factor involved in the pathophysiology of this complication, decreased red blood cell oxygen transport efficiency (i.e., low hematocrit/viscosity ratio) may play a role.
ISSN: 1932-6203

inserm-00922105
http://www.hal.inserm.fr/inserm-00922105
http://www.hal.inserm.fr/inserm-00922105/document
http://www.hal.inserm.fr/inserm-00922105/file/2013_Connes_-_Decreased_Hematocrit.pdf
DOI : 10.1371/journal.pone.0079680

Éditeur(s) : HAL CCSD
Résumé : International audience
Background: The aim of this study was to identify the predictive factors of HIV disclosure to the sex partner in HIV pregnant women in Cayenne (French Guiana). Methods: A case control study was conducted including all deliveries in Cayenne from 2003 to 2010. For each case, a standardized questionnaire including epidemiological, clinical, and biological data was administered. Thirty-four women in the first group and 95 in the control group were included in the study. Results: The logistic regression showed that the variables that independently predicted HIV disclosure to the sex partner were the existence of a profession (OR=5.62, IC95% =1.3-24.26, p=0.021), disclosure to the doctor (OR=12.65, IC95% =2.87-55.8, p<0.001), the negative representations of HIV (OR=5.99, IC95% =1.17-30.69, p=0.032). The partner's HIV status was also linked to the outcome (OR=0.01, IC95% =0.001-0.07, p<0.001). Conclusion: These predictive factors should be considered in positive prevention programs and prevention of mother to child transmission.
Epidemiol

inserm-00915113
http://www.hal.inserm.fr/inserm-00915113
http://www.hal.inserm.fr/inserm-00915113/document
http://www.hal.inserm.fr/inserm-00915113/file/2012_Elenga_-_Predictive_Factorssur HIV_Status_Disclosure_to_Sex_Partner_in_Pregnant_women_in_cayenne_french_guiana.pdf
DOI : 10.4172/2161-1165.1000116

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Sickle cell anemia (SCA) and hemoglobin SC (HbSC) disease are the two most common forms of sickle cell disease (SCD), a frequent hemoglobinopathy which exhibits a highly variable clinical course. Although high levels of microparticles (MPs) have been consistently reported in SCA and evidence of their harmful impact on the SCA complication occurrences have been provided, no data on MP pattern in HbSC patients has been reported so far. In this study, we determined and compared the MP patterns of 84 HbSC and 96 SCA children, all at steady-state, using flow cytometry. Most of circulating MPs were derived from platelets (PLTs) and red blood cells (RBCs) in the two SCD syndromes. Moreover, we showed that HbSC patients exhibited lower blood concentration of total MPs compared to SCA patients, resulting mainly from a decrease of MP levels originated from RBCs and to a lesser extent from PLTs. We did not detect any association between blood MP concentrations and the occurrence of painful vaso-occlusive crises, acute chest syndrome and pulmonary hyper-tension in both patient groups. We also demonstrated for the first time, that whatever the considered genotype, RBC-derived MPs exhibited higher externalized phosphatidylserine level and were larger than PLT-derived MPs.
ISSN: 1932-6203

hal-01668322
https://hal.univ-antilles.fr/hal-01668322
https://hal.univ-antilles.fr/hal-01668322/document
https://hal.univ-antilles.fr/hal-01668322/file/journal.pone.0177397.pdf
DOI : 10.1371/journal.pone.0177397

Éditeur(s) : HAL CCSD American Society of Tropical Medicine and Hygiene
Résumé : International audience
To study the link between climatic variables and the incidence of leishmaniasis a study was conducted in Cayenne, French Guiana. Patients infected between January 1994 and December 2010. Meteorological data were studied in relation to the incidence of leishmaniasis using an ARIMA model. In the final model, the infections were negatively correlated with rainfall (with a 2-month lag) and with the number of days with rainfall > 50 mm (lags of 4 and 7 months). The variables that were positively correlated were temperature and the Multivariate El Niño Southern Oscillation Index with lags of 8 and 4 months, respectively. Significantly greater correlations were observed in March for rainfall and in November for the Multivariate El Niño/Southern Oscillation Index. Climate thus seems to be a non-negligible explanatory variable for the fluctuations of leishmaniasis. A decrease in rainfall is linked to increased cases 2 months later. This easily perceptible point could lead to an interesting prevention message.
ISSN: 0002-9637

inserm-00913933
http://www.hal.inserm.fr/inserm-00913933
http://www.hal.inserm.fr/inserm-00913933/document
http://www.hal.inserm.fr/inserm-00913933/file/article_amaury_leishmaniose_revised2corrected.pdf
http://www.hal.inserm.fr/inserm-00913933/file/figure_2.pdf

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
BACKGROUND: Histoplasmosis is an endemic fungal infection in French Guiana. It is the most common AIDS-defining illness and the leading cause of AIDS-related deaths. Diagnosis is difficult, but in the past 2 decades, it has improved in this French overseas territory which offers an interesting model of Amazonian pathogen ecology. The objectives of the present study were to describe the temporal trends of incidence and mortality indicators for HIV-associated histoplasmosis in French Guiana. METHODS: A retrospective study was conducted to describe early mortality rates observed in persons diagnosed with incident cases of HIV-associated Histoplasma capsulatum var. capsulatum histoplasmosis admitted in one of the three main hospitals in French Guiana between 1992 and 2011. Early mortality was defined by death occurring within 30 days after antifungal treatment initiation. Data were collected on standardized case report forms and analysed using standard statistical methods. RESULTS: There were 124 deaths (45.3%) and 46 early deaths (16.8%) among 274 patients. Three time periods of particular interest were identified: 1992-1997, 1998-2004 and 2005-2011. The two main temporal trends were: the proportion of early deaths among annual incident histoplasmosis cases significantly declined four fold (χ2, p<0.0001) and the number of annual incident histoplasmosis cases increased three fold between 1992-1997 and 1998-2004, and subsequently stabilized. CONCLUSION: From an occasional exotic diagnosis, AIDS-related histoplasmosis became the top AIDS-defining event in French Guiana. This was accompanied by a spectacular decrease of early mortality related to histoplasmosis, consistent with North American reference center mortality rates. The present example testifies that rapid progress could be at reach if awareness increases and leads to clinical and laboratory capacity building in order to diagnose and treat this curable disease.
ISSN: 1935-2727

inserm-01065109
http://www.hal.inserm.fr/inserm-01065109
http://www.hal.inserm.fr/inserm-01065109/document
http://www.hal.inserm.fr/inserm-01065109/file/PLOS_Neglected_Tropical_Dis_2014.pdf
http://www.hal.inserm.fr/inserm-01065109/file/2014_Adenis_-_HIV-associated_histoplasmosis_early_mor.pdf

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Fungi are major contributors to the opportunistic infections that affect patients with HIV/AIDS. Systemic infections are mainly with Pneumocystis jirovecii (pneumocystosis), Cryptococcus neoformans (cryptococcosis), Histoplasma capsulatum (histoplasmosis), and Talaromyces (Penicillium) marneffei (talaromycosis). The incidence of systemic fungal infections has decreased in people with HIV in high-income countries because of the widespread availability of antiretroviral drugs and early testing for HIV. However, in many areas with high HIV prevalence, patients present to care with advanced HIV infection and with a low CD4 cell count or represent with persistent low CD4 cell counts because of poor adherence, resistance to antiretroviral drugs, or both. Affordable, rapid point-of-care diagnostic tests (as have been developed for cryptococcosis) are urgently needed for pneumocystosis, talaromycosis, and histoplasmosis. Additionally, antifungal drugs, including amphotericin B, liposomal amphotericin B, and flucytosine, need to be much more widely available. Such measures, together with continued international efforts in education and training in the management of fungal disease, have the potential to improve patient outcomes substantially.
ISSN: 1473-3099

inserm-01574426
http://www.hal.inserm.fr/inserm-01574426
http://www.hal.inserm.fr/inserm-01574426/document
http://www.hal.inserm.fr/inserm-01574426/file/2017%2C%20Limper%20-%20Fungal%20infections%20in%20HIV%20AIDS.pdf
DOI : 10.1016/S1473-3099(17)30303-1

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
ISSN: 1935-2727

inserm-00919502
http://www.hal.inserm.fr/inserm-00919502
http://www.hal.inserm.fr/inserm-00919502/document
http://www.hal.inserm.fr/inserm-00919502/file/2013_Nacher_-_Disseminated_histo_in_hiv_in_south_america_a_neglected_killer_continues_on_its_rampage.pdf
DOI : 10.1371/journal.pntd.0002319

Éditeur(s) : HAL CCSD American Society of Tropical Medicine and Hygiene
Résumé : International audience
In disease-endemic areas, histoplasmosis is the main differential diagnosis for tuberculosis among human immunodeficiency virus (HIV)-infected patients. However, no study has compared the two diseases. Thus, the objective of this study was to compare tuberculosis and histoplasmosis in HIV-infected patients. A population of 205 HIV-infected patients (99 with tuberculosis and 106 with histoplasmosis) hospitalized in Cayenne, French Guiana during January 1, 1997-December 31, 2008 were selected retrospectively from the French Hospital Database on HIV. Multivariate analysis showed that tuberculosis was associated with cough (adjusted odds ratio [AOR] = 0.20, 95% confidence interval [CI] = 0.05-0.73) and a C-reactive protein level > 70 mg/L (AOR = 0.98, 95% CI = 0.97-0.99). Variables associated with disseminated histoplasmosis were a γ-glutamyl transferase level > 72 IU/L (AOR = 4.99, 95% CI = 1.31-18.99), origin from French Guiana (AOR = 5.20, 95% CI = 1.30-20.73), disseminated localization (AOR = 6.40, 95% CI = 1.44-28.45), a concomitant opportunistic infection (AOR = 6.71, 95% CI = 1.50-29.96), a neutrophil count < 2,750 cells/mm(3) (AOR = 10.54, 95% CI = 2.83-39.24), a CD4 cell count < 60 cells/mm(3) (AOR = 11.62, 95% CI = 2.30-58.63), and a platelet count < 150,000/mm(3) (AOR = 19.20, 95% CI = 3.35-110.14). Tuberculosis and histoplasmosis have similarities, but some factors show a greater association with one of these diseases. Thus, adapted therapeutic choices can be made by using simple clinical and paraclinical criteria.
ISSN: 0002-9637

inserm-01065027
http://www.hal.inserm.fr/inserm-01065027
http://www.hal.inserm.fr/inserm-01065027/document
http://www.hal.inserm.fr/inserm-01065027/file/2014_Adenis_-_Tuberculosis_and_Histoplasmosis_among_HIV.pdf
DOI : 10.4269/ajtmh.13-0084

Éditeur(s) : HAL CCSD SAGE Publications
Résumé : International audience
In Western French Guiana there was a dramatic increase in HIV-prevalence between 1990 and 2000. The present study describes the causes of fever among HIV patients hospitalized in the medical ward of the only hospital in the western part of French Guiana. A retrospective descriptive study was conducted between January 1st 2008 and June 30th 2010 in the department of medicine of Saint Laurent du Maroni Hospital. The main characteristics of 67 patients having presented with fever in the first 48 hours of hospitalization were described. Among patients with CD4<200/mm3 the main febrile opportunistic infection was disseminated histoplasmosis (41.1%). Among patients with CD4 counts <50/mm3 and fever without focal points 85.7% had disseminated histoplasmosis. Three patients died and all had disseminated histoplasmosis. Disseminated histoplasmosis is the most common febrile opportunistic infection in western French Guiana. Primary prophylaxis with itraconazole among immunocompromised patients seems warranted.
ISSN: 0956-4624

inserm-01082409
http://www.hal.inserm.fr/inserm-01082409
http://www.hal.inserm.fr/inserm-01082409/document
http://www.hal.inserm.fr/inserm-01082409/file/2014%2C%20Vantilcke%20-%20Fever%20and%20HIV.pdf
http://www.hal.inserm.fr/inserm-01082409/file/Histoplasmosis_tab_2%5B1%5D%20revised.pdf

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
The nine countries sharing the Amazon forest accounted for 89% of all malaria cases reported in the Americas in 2008. Remote sensing can help identify the environmental determinants of malaria transmission and their temporo-spatial evolution. Seventeen studies characterizing land cover or land use features, and relating them to malaria in the Amazon subregion, were identified. These were reviewed in order to improve the understanding of the land cover/use class roles in malaria transmission. The indicators affecting the transmission risk were summarized in terms of temporal components, landscape fragmentation and anthropic pressure. This review helps to define a framework for future studies aiming to characterize and monitor malaria.
ISSN: 1475-2875

inserm-00834790
http://www.hal.inserm.fr/inserm-00834790
http://www.hal.inserm.fr/inserm-00834790/document
http://www.hal.inserm.fr/inserm-00834790/file/1475-2875-12-192.pdf
DOI : 10.1186/1475-2875-12-192

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
ISSN: 1935-2727

hal-00921369
https://hal-unilim.archives-ouvertes.fr/hal-00921369
DOI : 10.1371/journal.pntd.0001802
PUBMED : 23145185

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Patients with sickle cell anemia (SCA) have usually lower diastolic, systolic and mean blood pressure (BP) than the general population. However, BP values ≥120/70 mmHg considerably increase the risk for acute and chronic complications in SCA. The aim of this study was to identify biological factors associated with relative hypertension in adults with SCA. We compared the hematological, lipid and hemolytic profiles, as well as blood viscosity, between SCA patients with normal BP (<120/70 mmHg, n = 54) and those with relative hypertension (BP≥120/70 mmHg, n = 43). Our results demonstrated that male gender (OR: 3.49; 95%CI 1.20 to 10.16, p<0.05), triglycerides (OR: 9.19; 95% CI 2.29 to 36.95, p<0.01), blood viscosity (OR: 1.35; 95% CI 1.01 to 1.81, p<0.05) and body mass index (OR: 1.37; 95% CI 1.14 to 1.64, p<0.01) were independent risks factors for relative hypertension in SCA. No association was found between the BP status and the positive history of painful vaso-occlusive crisis or acute chest syndrome. An association between triglycerides level and the occurrence of these two major acute complications was detected. Our study suggests that male gender, increased triglycerides level, BMI and blood viscosity could increase the risk for developing relative hypertension in SCA. In addition, our results support a role of moderately elevated triglycerides in the pathophysiology of vaso-occlusive events.
ISSN: 1932-6203

inserm-00838991
http://www.hal.inserm.fr/inserm-00838991
http://www.hal.inserm.fr/inserm-00838991/document
http://www.hal.inserm.fr/inserm-00838991/file/Lamarre_et_al._2013_PloS_ONE_.pdf
DOI : 10.1371/journal.pone.0066004

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
: Malaria is a public health problem in French Guiana. Plasmodium vivax is the most frequent parasite. The objective of this analysis was to estimate the proportion of relapses in the burden of vivax malaria using the statistical rule stating that any case of vivax malaria occurring less than 90 days following a first episode is a relapse.A total of 622 subjects were followed for 2,9 years with 336 first single episodes of P. vivax malaria, and a total of 1,226 episodes of vivax malaria among which 559 were relapses (45.5%). For 194 patients having had falciparum malaria followed by vivax malaria it was estimated that 19% of the vivax episodes occurred less than 90 days following the falciparum episode and thus were possibly relapses due to the activation of latent hypnozoites. Despite the number of vivax cases and the number of relapses, there were only 28 recorded primaquine prescriptions (3.4% of vivax episodes, 4.5% of subjects).The present study points out that despite the fact that nearly half of the P. vivax cases, many of which in children, are caused by latent hypnozoites, only a minority of them benefit from primaquine radical cure. The obstacles to this are discussed and suggestions are made to reduce the burden of vivax malaria in Camopi and other remote health centres in French Guiana.
ISSN: 1475-2875

inserm-00903890
http://www.hal.inserm.fr/inserm-00903890
http://www.hal.inserm.fr/inserm-00903890/document
http://www.hal.inserm.fr/inserm-00903890/file/1475-2875-12-367.pdf
DOI : 10.1186/1475-2875-12-367

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
Plasmodium vivax malaria is an important public health issue in the Amazon region, and it accounts for approximately 84 % of cases of the disease. Migration across the border between Brazil and French Guiana contributes to the maintenance of the disease. The aim of this study was to evaluate the therapeutic and parasitological responses of patients with P. vivax malaria treated with chloroquine and primaquine in the socio-environmental context of cross-border interactions between Brazil and French Guiana. The factors controlled were diagnostic agreement, adherence, adjustment of primaquine doses for patient weight, and quality of the drugs used. A prospective study was conducted in 2011 with 103 individuals aged 10-60 years with a positive diagnosis of P. vivax treated with chloroquine (10 mg base/kg on the first day, followed by 7.5 mg/kg on the second and third days) and primaquine for 7 days, who were followed for 28 days. The primaquine doses were adjusted for the patients' weight. A number of factors were determined: epidemiological characteristics, origin of patients, signs and symptoms, initial parasitaemia and parasitaemia clearance time, blood concentrations of chloroquine and primaquine, quality of anti-malarial drugs and diagnostic agreement. Ninety-five patients were followed for 28 days. There was a 100 % agreement in microscopic diagnosis between field laboratory and reference centre. The adhesion to the treatment was 100 %. Of these patients, 32.6 % received a weight-adjusted dose of primaquine. The chloroquine and primaquine tablets were consistent with the optimal quality limits for human consumption. The investigated patients achieved optimal blood exposure to anti-malarial drugs. The parasitological and therapeutic response was adequate in 99.0 % of cases. In the municipality of Oiapoque, the therapeutic regime used for the treatment of P. vivax malaria using chloroquine combined with primaquine remains effective, when external factors are controlled, such as the quality of anti-malarial drugs, the adhesion to the treatment prescribed, the correct diagnostic and the adjustment of primaquine dose for patient body weight.
ISSN: 1475-2875

Droits : http://creativecommons.org/licenses/by/
pasteur-01229355
https://hal-pasteur.archives-ouvertes.fr/pasteur-01229355
https://hal-pasteur.archives-ouvertes.fr/pasteur-01229355/document
https://hal-pasteur.archives-ouvertes.fr/pasteur-01229355/file/s12936-015-0925-7.pdf
PUBMEDCENTRAL : PMC4600333

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND: In Guadeloupe and Martinique, two French Overseas Departments, colorectal cancer (CRC) has become an essential public health issue. However, little is known about CRC characteristics and the p53 status in these populations, particularly in Guadeloupe, whereas certification of a cancer registry has been recently validated. METHODS: This was a descriptive retrospective study of 201 patients who, between 1995 and 2000, underwent surgery for CRC in the Guadeloupe Teaching Hospital (GlpeTH; 83 patients) and in the Martinique Teaching Hospital (MqueTH; 118 patients). The clinicopathological features and the p53 expression, evaluated with immunohistochemistry, were compared at the time of diagnosis. A relationship between these parameters and the p53 expression was also studied. Data were analysed, using the SPSS computer software version 17.0. RESULTS: No statistical difference was found between the two groups of patients regarding age (p = 0.60), percentage of young patients (<=50 years; p = 0.94)), sex (p = 0.47), histological type (p = 0.073) and tumour sites (p = 0.65), although the GlpeTH patients were diagnosed with more distal colon cancers (54.2%) than the Mque TH patients (47.4%). By contrast, a significant difference was found regarding the tumour grade (p < 0.0001), the pTNM stage (p = 0.045) and the pT stage (p < 0.0001). Regarding p53 expression, solely for the MqueTH patients, nuclear expression was associated with pTNM, the percentage of p53 negative tumours increasing with the progression of the pTNM stages (p = 0.029). CONCLUSIONS: For the first time, this study reveals discrepancies in clinicopathological features and in the p53 status between the two groups of patients. The GlpeTH patients were diagnosed with more moderated CRCs but with few CRCs at pTNM IV stage. By contrast, the MqueTH patients were diagnosed with more differentiated tumours, but with many more CRCs at pTNM IV stage. This paradox may be due to differences in tumour location (distal vs proximal), multiplicity of the genetic profiles of patients, or patients getting treatment elsewhere. Although our study is limited due to its small size, it emphasizes the originality of our results.
ISSN: 1472-6890

inserm-00971313
http://www.hal.inserm.fr/inserm-00971313
http://www.hal.inserm.fr/inserm-00971313/document
http://www.hal.inserm.fr/inserm-00971313/file/1472-6890-14-12.pdf
DOI : 10.1186/1472-6890-14-12

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
BACKGROUND/AIM: Although it has been hypothesized that muscle metabolism and fatigability could be impaired in sickle cell patients, no study has addressed this issue. METHODS: We compared muscle metabolism and function (muscle microvascular oxygenation, microvascular blood flow, muscle oxygen consumption and muscle microvascular oxygenation variability, which reflects vasomotion activity, maximal muscle force and local muscle fatigability) and the hemorheological profile at rest between 16 healthy subjects (AA), 20 sickle cell-hemoglobin C disease (SC) patients and 16 sickle cell anemia (SS) patients. RESULTS: Muscle microvascular oxygenation was reduced in SS patients compared to the SC and AA groups and this reduction was not related to hemorhelogical abnormalities. No difference was observed between the three groups for oxygen consumption and vasomotion activity. Muscle microvascular blood flow was higher in SS patients compared to the AA group, and tended to be higher compared to the SC group. Multivariate analysis revealed that muscle oxygen consumption was independently associated with muscle microvascular blood flow in the two sickle cell groups (SC and SS). Finally, despite reduced muscle force in sickle cell patients, their local muscle fatigability was similar to that of the healthy subjects. CONCLUSIONS: Sickle cell patients have normal resting muscle oxygen consumption and fatigability despite hemorheological alterations and, for SS patients only, reduced muscle microvascular oxygenation and increased microvascular blood flow. Two alternative mechanisms can be proposed for SS patients: 1) the increased muscle microvascular blood flow is a way to compensate for the lower muscle microvascular oxygenation to maintain muscle oxygen consumption to normal values or 2) the reduced microvascular oxygenation coupled with a normal resting muscle oxygen consumption could indicate that there is slight hypoxia within the muscle which is not sufficient to limit mitochondrial respiration but increases muscle microvascular blood flow.
ISSN: 1932-6203

inserm-00849035
http://www.hal.inserm.fr/inserm-00849035
http://www.hal.inserm.fr/inserm-00849035/document
http://www.hal.inserm.fr/inserm-00849035/file/2013_Waltz_-_Normal_muscle_oxygen_consumption_and_fatigability_in_sickle_cell_patients.pdf
DOI : 10.1371/journal.pone.0052471

Éditeur(s) : HAL CCSD American Society of Hematology
Résumé : International audience
ISSN: 0006-4971

inserm-00919490
http://www.hal.inserm.fr/inserm-00919490
http://www.hal.inserm.fr/inserm-00919490/document
http://www.hal.inserm.fr/inserm-00919490/file/2013_Lemonne_-_Does_increased_red_blood_cell_deformability_raise_the_risk_for_osteonecrosis_in_sickle_cell_anemia.pdf
http://www.hal.inserm.fr/inserm-00919490/file/inserm-00919490_edited.pdf

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The present study investigated cerebral and muscle hemoglobin oxygen saturation (tissue oxygen index, TOI) in children with sickle cell anemia (SS), sickle cell hemoglobin C disease (SC) and healthy children (AA). TOI was measured by near-infrared spectroscopy (NIRS) and spectral analysis of the TOI variability was used to assess flowmotion and vasomotion. Arterial oxyhemoglobin saturation (SpO2), hemorheological and hematological parameters were also measured in SS and SC children. Both TOI were lower in SS compared to both AA and SC children, with SC exhibiting lower values than AA children. Cerebral vasomotion expressed in absolute values was enhanced in SS compared to AA and SC children. Muscle vasomotion did not differ between the three groups. Hematocrit, SpO2 and red blood cell deformability were positively associated with cerebral TOI in SS children. We demonstrated that 1) cerebral and muscle TOI were markedly decreased in SS children while the decrease of TOI was milder in SC children, 2) cerebral TOI level was associated with several biological markers in SS children only and 3) cerebral vasomotion was enhanced in SS, possibly to counterbalance the effects of chronic cerebral hypoxia.
ISSN: 1079-9796

hal-01668321
https://hal.univ-antilles.fr/hal-01668321
DOI : 10.1016/j.bcmd.2017.03.015