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Biomedical subjects

R Girot

Publications and source records attributed to R Girot.

At least 37 records · Page 2Linked to original sources
PubMed1999

Prevalence of GB virus type C/hepatitis G virus RNA and of anti-E2 in individuals at high or low risk for blood-borne or sexually transmitted viruses: evidence of sexual and parenteral transmission.

BACKGROUND: The first epidemiologic evidence of GB virus type C (GBV-C)/hepatitis G virus (HGV) infection showed a high prevalence of asymptomatic carriers in blood donors and in populations at risk for blood-borne viruses. However, by using only viral RNA polymerase chain reaction, those studies underestimated the true spread of GBV-C/HGV infection. The combined detection of GBV-C/HGV RNA and of anti-E2 (which reflects recovery from infection) is necessary to define accurately the prevalence of GBV-C/HGV. STUDY DESIGN AND METHODS: The presence of both anti-E2 and GBV-C/HGV RNA was searched for in 1438 serum samples collected from various groups of individuals at low or high risk for blood-borne or sexually transmitted viruses (blood donors, organ donors, unselected pregnant women, immunocompetent or immunodepressed multiply transfused patients, HIV-positive or HIV-negative homosexual men, intravenous drug addicts). RESULTS: The presence of GBV-C/HGV RNA and/or anti-E2 (exposure to GBV-C/HGV) was frequent in populations at risk for blood-borne or sexually transmitted viruses. GBV-C/HGV appeared also to be sexually transmitted, with transmission from male to female more efficient than vice versa. A particularly elevated level of exposure to GBV-C/HGV was observed in homosexual men. In immunocompetent individuals, the prevalence of anti-E2 was about twice that of GBV-C/HGV RNA, which suggests the frequency of recovery from GBV-C/HGV infection. Most of the GBV-C/HGV RNA-positive individuals had no biochemical evidence of liver damage. CONCLUSIONS: GBV-C/HGV is frequent in populations at risk for blood-borne or sexually transmitted viruses. GBV-C/HGV is not a hepatitis virus, and it seems appropriate to rename it.

Alanine Transaminase↗
PubMed1999

Identification of new prognosis factors from the clinical and epidemiologic analysis of a registry of 229 Diamond-Blackfan anemia patients. DBA group of Société d'Hématologie et d'Immunologie Pédiatrique (SHIP), Gesellshaft für Pädiatrische Onkologie und Hämatologie (GPOH), and the European Society for Pediatric Hematology and Immunology (ESPHI).

Diamond-Blackfan anemia (DBA) is a constitutional disease characterized by a specific maturation defect in cells of erythroid lineage. We have assembled a registry of 229 DBA patients, which includes 151 patients from France, 70 from Germany, and eight from other countries. Presence of malformations was significantly and independently associated with familial history of DBA, short stature at presentation (before any steroid therapy), and absence of hypotrophy at birth. Two hundred twenty-two patients were available for long-term follow-up analysis (median, 111.5 mo). Of these individuals, 62.6% initially responded to steroid therapy. Initial steroid responsiveness was found significantly and independently associated with older age at presentation, familial history of DBA, and a normal platelet count at the time of diagnosis. Severe evolution of the disease (transfusion dependence or death) was significantly and independently associated with a younger age at presentation and with a history of premature birth. In contrast, patients with a familial history of the disease experienced a better outcome. Outcome analysis revealed the benefit of reassessing steroid responsiveness during the course of the disease for initially nonresponsive patients. Bone marrow transplantation was successful in 11/13 cases; HLA typing of probands and siblings should be performed early if patients are transfusion dependent, and cord blood should be preserved. Incidence of DBA (assessed for France over a 13-y period) is 7.3 cases per million live births without effect of seasonality on incidence of the disease or on malformative status. Similarly, no parental imprinting effect or anticipation phenomenon could be documented in families with dominant inheritance.

Abnormalities, Multiple↗
PubMed1999

[Sickle cell anemia and pregnancy. Complications and management].

An increasing number of sickle cell disease patients are deciding to bear children. The high risk of fetal and maternal complications in pregnant sickle cell disease patients mandates multidisciplinary management. Risks include spontaneous abortion, vasculorenal syndrome, fetal growth retardation, and fetal death in utero. The rates of cesarean section, maternofetal infection, and maternal death are higher than in the population at large. The diagnosis should be made prior to conception or during early pregnancy. Frequent visits with the obstetrician, hematologist, and anesthesiologist/intensivist are mandatory. Exchange transfusion or blood transfusion may be indicated in patients with a history of serious obstetrical or hematologic complications. Risks are highest in late pregnancy, during delivery, and in the postpartal period. However, the entire pregnancy is a high-risk period that warrants close monitoring.

Anemia, Sickle Cell↗
PubMed1999

[Contributions to the sociologic analysis of the impact of sickle cell disease on families from Northern Tunisia].

The improvement of the conditions of care and quality of life of people living with drepanocytosis now constitutes a major concern of health authorities and voluntary groups (associations of sick people and their parents). In order to examine the conditions and methods of care for children living with drepanocytosis in the Bizerte region of Northern Tunisia and to understand the problems and difficulties experienced by them and their families in their daily lives, an anthropological study was carried out in the region between January 16 and February 12, 1997. Thirty-three interviews were carried out with families of infected children. The interviews were semi-directive using a pre-established protocol (interview guide). Thirty interviews were then analysed. A multitude of information concerning various medical and psycho-social aspects of drepanocytosis in the region were revealed. The data were regrouped into the following categories: circumstances of discovering the illness; explicative model of the illness as perceived by the people interviewed; conditions and methods of care of the sick child; degree of satisfaction with the health care system; psychological profile of the children interviewed; educational level of the children interviewed; repercussions the illness has on the family; impact of the illness on household budget; suggestions and comments of the people interviewed. In light of the information collected, various actions have been proposed with the goal of improving the conditions of care and quality of life of people living with drepanocytosis in the region.

Anemia, Sickle Cell↗
PubMed1998

High adenosine deaminase level among healthy probands of Diamond Blackfan anemia (DBA) cosegregates with the DBA gene region on chromosome 19q13. The DBA Working Group of Société d'Immunologie Pédiatrique (SHIP).

Phenotypic characterization of Diamond Blackfan Anemia (DBA) patients and their relatives was performed in 54 families. Complete blood count, fetal hemoglobin level, erythrocyte i antigen expression, and erythrocyte adenosine deaminase (eADA) activities were quantitated in patients and relatives. eADA was elevated in 28 of 34 transfusion-independent DBA patients, whereas persistence of erythrocyte i antigen was noticed in only 10 of 20 DBA patients. High eADA activities were also found in 14 of 149 healthy family members, allowing us to identify an isolated high eADA phenotype in these families. In contrast, increase in erythrocyte i antigen expression, elevated fetal hemoglobin levels, and macrocytosis were much less frequently noted in nonaffected members of the DBA families studied. Importantly, isolated high eADA phenotype was found to be significantly associated with genetic markers on chromosome 19 that segregate with the DBA phenotype. Isolated high eADA phenotype thus seems to reflect a silent phenotype of DBA in affected families. These findings suggest that elevated eADA activity in unaffected individuals needs to be taken into account during genetic assessment of DBA families and could be used for accurate assessment of mode of inheritance.

Adenosine Deaminase↗
PubMed1998

Serum ferritin, desferrioxamine, and evolution of HIV-1 infection in thalassemic patients.

To study the respective roles of mean serum ferritin level and the mean desferrioxamine (DFX) dose on progression of HIV-1 infection, data from 49 HIV-seropositive thalassemic patients were analyzed using a Cox proportional hazards model including known confounding variables. Nine years after seroconversion, 10% of those who had been prescribed >40 mg/kg of DFX daily had entered stage IV versus 39% of those who had been prescribed a lower dose. Patients with ferritin level >1935 g/L entered stage IV more rapidly than those with a lower level (31% versus 16%). In multivariate analysis, the ferritin level was found to be an independent predictor of progression of HIV disease, whereas the mean daily dose of DFX was not. Similar results were obtained when death was the endpoint. Our results support a hypothesis that was recently expressed, that iron overload could be associated with a more rapid progression of HIV-1 infection.

Child↗
PubMed1998

Fetal hemoglobin and F-cell responses to long-term hydroxyurea treatment in young sickle cell patients. The French Study Group on Sickle Cell Disease.

We have studied the cellular and molecular responses to long-term hydroxyurea (HU) treatment in 29 severely affected young patients with sickle cell disease (mean age, 10.9 +/- 4.1 years). Patients received HU at 20 mg/kg/d on 4 consecutive days per week initially, with a monthly escalated dose avoiding marrow-toxicity (mean steady-state dose, 34.2 +/- 4.6 mg/kg/d) for 12 to 36 months (mean duration, 22 months). The studied parameters were hemoglobin F (HbF), F reticulocytes (F retics), F cells, the amount of HbF per F cell (F/F cell), polymer tendency at 40% and 70% oxygen saturation, and hemolysis. Initial HbF (Fi) was dispersed (from 0.85% to 13.9%). HbF increased in all patients but 1. HbF at maximal response (Fmax) reached a sustained level varying from a 1.5-fold to a 16-fold Fi after a variable delay (6 to 24 months). Fmax was not related to HU dosage, but triangle upF (Fmax - Fi) was strongly correlated to triangle upMCV (MCVmax - MCVi). HbF increase resulted from the increase of both F cells and F/F cell. In this rather short series, Fi and Fmax were not significantly associated with age, gender, or beta-globin haplotype. Neither Fmax nor triangle upF was related to bone marrow reserve, as measured by baseline reticulocyte or neutrophil counts. However, Fmax was highly dependent on Fi. When patients are individualized into three groups according to Fmax (group 1, Fmax >20% [12 patients]; group 2, 10% < Fmax < 20% [11 patients]; group 3, Fmax <10% [5 patients]), Fi is significantly different between groups, being the highest in group 1. In addition, the best responders (group 1) were significantly different from patients in the two other groups with higher levels of total hemoglobin, decreased bilirubin, and decreased polymer tendency.

Adolescent↗
PubMed1998

Early glomerular dysfunction in patients with sickle cell anemia.

The purpose of this study was to analyze the determinants of glomerular filtration in nonnephrotic young adult patients with sickle cell anemia (SCA). We prospectively screened 14 patients with homozygous SCA who had normal plasma creatinine concentrations and normal or moderately elevated albuminuria (< 1 g/d). Inulin, paraaminohippuric acid, and dextran clearances were evaluated and compared with values obtained from a control group (age-matched healthy volunteers). SCA patients had a significantly higher glomerular filtration rate and effective renal plasma flow than controls (146 +/- 9 mL/min/1.73 m2 v 120 +/- 3 mL/min/1.73 m2 [P < 0.01] and 1,052 +/- 69 mL/min/1.73 m2 v 709 +/- 38 mL/min/1.73 m2 [P < 0.001], respectively). We found no correlation between glomerular filtration rate or effective renal plasma flow and hematocrit. Fractional clearance of neutral dextran was significantly elevated in SCA patients for all radii between 3.4 and 5.4 nm. Theoretical analysis of dextran transport through a heteroporous membrane model revealed a slight increase in the mean radius (ro) of restrictive pores (5.68 nm v5.50 nm; P < .001) and no significant difference in shunt pathway (omega o) values. Among the other hemodynamic parameters, the most significant change was a dramatic increase in ultrafiltration coefficient (41.3 +/- 3.6 mL/mm Hg/min/1.73 m2 v 25.1 +/- 2.6 mL/mm Hg/min/1.73 m2; P < 0.001). Our results suggest that hyperfiltration in SCA patients is associated not only with enhanced renal perfusion but also with an alteration in glomerular permeability and with an increase in Kf. This change in Kf is fully in agreement with the large increase in glomerular area previously described in SCA patients. Based on our results and those of previous morphologic studies, we propose that enhanced transglomerular trafficking of macromolecules associated with podocyte stretch lesions (defects) induced by glomerular hypertrophy may play a role in the genesis of this particular form of focal segmental glomerulosclerosis, which is associated with SCA.

Adult↗
PubMed1998

Hepatitis C associated with Guillain-Barré syndrome.

Hepatitis C is frequently associated with immune-mediated diseases, such as cryoglobulinemia. Guillain-Barré syndrome is an acute demyelinating neuropathy of probable immune pathogenesis. We describe two patients with Guillain-Barré syndrome, and associated chronic hepatitis C, the second one previously treated with interferon. The link between both conditions may be hepatitis C being the trigger of this immune polyneuropathy. Guillain-Barré syndrome should be added to the list of conditions associated with hepatitis C.

Adolescent↗
PubMed1998

Hb Godavari [alpha 95(G2)Pro-->Thr]: a neutral amino acid substitution in the alpha 1 beta 2 interface that modifies the electrophoretic mobility of hemoglobin.

Hb Godavari [alpha 95(G2)Pro-->Thr] was characterized independently in two families of different ethnic origin. The first case, found in the Netherlands, involved an Indian patient. The second one was identified a few months later in an African family from Mali, living in France. Hb Godavari is the fourth example of a substitution involving neutral residues at position alpha 95(G2). In all these variants the electrophoretic pattern suggested that the structural modification unmasks a charged residue buried in the alpha 1 beta 2 contact area. The oxygen affinity of this abnormal hemoglobin was approximately 10% higher than that of Hb A; in the absence of 2,3-diphosphoglycerate, its cooperativity was moderately decreased, suggesting a slightly unstable T state.

Adult↗
PubMed1997

Natural history of GBV-C/hepatitis G virus infection through the follow-up of GBV-C/hepatitis G virus-infected blood donors and recipients studied by RNA polymerase chain reaction and anti-E2 serology.

The aims of this study were to determine the outcome and the natural history of GBV-C/hepatitis G virus (HGV) infection and to establish the frequency of acute or persistent infections in multiply-transfused individuals and blood donors. We used a GBV-C/HGV RNA polymerase chain reaction (PCR) and an assay evidencing antibodies to the envelop protein E2, which is considered a marker for virus clearance. Among 16 PCR-positive recipients, 11 were still positive for GBV-C/HGV RNA at the end of the study period; six of the 16 recipients were GBV-C/HGV infected during the study period and thus had a well-defined date of infection. The 16 patients were shown to carry GBV-C/HGV RNA over a mean period of 4.4 years, for a mean observational period (defined as the follow-up period since the first sample positive for GBV-C/HGV RNA) of 5.3 years. Within the limits of the study period, the patients with a well-defined date of infection were positive for GBV-C/HGV RNA during a mean period of 4.7 years. If defined by the presence of GBV-C/HGV RNA for at least 6 months, the persistent infection rate was 100% in this recipient cohort. Serum anti-E2 antibody was evidenced at least once in five (31.2%) recipients and, except in one case, became detectable after the loss of GBV-C/HGV RNA. Among the 11 blood donors, all were still positive for GBV-C/HGV RNA after a mean follow-up period of 7.7 months. The persistent infection rate was 100% in this donor cohort. Once acquired, the infection to GBV-C/HGV generally tends to persist in immunocompetent patients.

Adenovirus E2 Proteins↗
PubMed1997

[Prevention and treatment of erectile disorders in sickle cell disease].

Priapism is a frequent and serious cause of morbidity in males with sickle cell disease. Acute priapism (AP) is preceeded in two-thirds of the cases by repeated minor events called stuttering priapism (SP). Since 1994, we have used a specific approach to prevent the commonly devastating effects of AP, using the alpha adrenergic agent etilefrine. Treatment of AP has been simplified (drainage without aspiration followed by one or two intracavernous injections (ICI) of 10 mg of etilefrine, until detumescence). For SP lasting more than one hour or causing pain, we use oral etilefrine and/or self ICI. This strategy was effective in five patients seen having AP, 21 patients with SP; it is simple, cheap, and avoids surgical procedure and transfusion. Moreover, erectile dysfunction, present in three patients, has been treated safely by ICI of protaglandins.

Adolescent↗
PubMed1997

Inappropriate iron intake in children on long-term parenteral nutrition: outcome after iron withdrawal.

Inappropriate parenteral iron intake in children on long-term parenteral nutrition can be responsible for iron overload. This study was carried out to monitor iron status changes when iron parenteral intake was stopped in case of iron overload. Seven children with serum ferritin concentrations above 800 ng/ml (6 with documented liver iron overload) were prospectively studied after total discontinuation of parenteral iron intake and without chelation therapy. Iron status was assessed, by means of ferritin and iron plasma concentrations, 8-15 months (T(1)) and 24-30 months (T(2)) after withdrawal of parenteral iron. Ferritin and iron concentrations declined at T(1), or T(2) in all but two children. At T(2) ferritin and iron concentrations were significantly lower (P < 0.05) than before iron parenteral discontinuation with a yearly reduction of 22 +/- 15% and 15 +/- 16%, respectively, for ferritin concentration and iron concentration. This fall in serum ferritin concentration is comparable to thalassemic subjects after bone marrow transplantation. The total withdrawal of parenteral iron intake improves iron status in children with iron overload. Nevertheless, iron overload related parenteral nutrition should be avoided by lowering iron intake in case of long-term total parenteral nutrition and by careful monitoring.

Journal Article↗
PubMed1997

Sickle cell disease: relation between procoagulant activity of red blood cells from different phenotypes and in vivo blood coagulation activation.

In the present study we examined if, among other mechanisms, the abnormal exposure of phosphatidylserine at the surface of sickle red blood cells (RBCs) contributes to the hypercoagulability which characterizes homozygous sickle cell disease (SCD). The question was addressed by comparison of the procoagulant properties of RBCs from subjects with various phenotypes (SS, SC and AS) that differ in clinical presentation. As previously reported, SS-RBCs accelerated the prothrombin activation by factor Xa, by decreasing the Km of the reaction compared to normal RBCs. SC-RBCs and AS-RBCs also promoted prothrombin activation although their procoagulant properties were milder compared to SS-RBCs. A significant increase of the thrombin-antithrombin complexes was observed in SS subjects. Prothrombin fragment 1+2 (F1+2) was elevated in half of the SS subjects, but the difference with controls did not reach significance. Elevated levels of thrombin-antithrombin complexes were observed in a number of SC (4/11) and AS (3/12) subjects, but the difference with controls was not significant. A significant correlation was observed between the plasma levels of thrombin-antithrombin complexes in the subjects with SS, AS and AA phenotypes, and the procoagulant properties of RBCs. Our results strongly suggest that the procoagulant properties which characterize SS-RBCs also affect SC-RBCs and AS-RBCs, and that exposure of phosphatidylserine by RBCs contributes to the hypercoagulable state observed in SCD.

Adult↗
PubMed1997

The relative importance of the X-linked FCP locus and beta-globin haplotypes in determining haemoglobin F levels: a study of SS patients homozygous for beta S haplotypes.

Five factors have been hypothesized to influence the 20-fold variation in fetal haemoglobin (Hb F) levels in sickle cell anaemia (SS): age sex, alpha-globin gene number, beta-globin haplotype, and the X-linked F-cell production locus (FCP) that regulates the production of Hb F containing erythrocytes (F cells). We analysed the association of these factors with Hb F levels in 112 SS patients living in France who are homozygous for the three common African beta-globin haplotypes (Benin, Bantu or Central African Republic and Senegal). We found that: (1) FCP accounts for about 40% of the overall variation in Hb F levels, (2) when the FCP influence is removed, beta-globin haplotype is associated with 14% of the remaining Hb F variation, and (3) the other factors have little influence. Comparison with our previous study of SS individuals in Jamaica leads to the following conclusions: (1) the X-linked FCP locus is a major determinant of Hb F levels in SS disease, (2) factors linked to the beta-globin haplotype have only a small effect on the variation in Hb F levels, in either the homozygous or heterozygous state, and (3)approximately half of the variation in Hb F levels still remains to be explained.

Adolescent↗
PubMed1997

Prevalence of hepatitis G virus RNA in French blood donors and recipients.

BACKGROUND: Recently, cases of chronic hepatitis were linked to the presence of genomic sequences of a newly described RNA virus termed hepatitis G virus (HGV) and belonging to the Flaviviridae family. STUDY DESIGN AND METHODS: The presence of HGV RNA was searched for by polymerase chain reaction in a population of blood donors and in patients who had received multiple blood component transfusions and/or intravenous immunoglobulin (IVIG) infusions. RESULTS: Twenty-one (4.2%) of 500 donors were positive for HGV RNA as were 21 (10.7%) of 196 nonimmunosuppressed patients who had received multiple transfusions of packed red cells, 4 (8.7%) of 46 common variable immune deficiency (CVID) patients who had received only IVIG, and 22 (24.7%) of 89 bone marrow transplant (BMT) patients who had received IVIG and cellular components. The proportion of HGV-positive individuals was significantly higher in the immunosuppressed recipients (CVID and BMT patients) than in the nonimmunosuppressed patients who were multiply transfused with packed red cells (p < 0.03). The proportion of HGV-positive individuals was significantly higher in the BMT patients who had received IVIG and cellular components than in the CVID patients who had received IVIG only (p < 0.03). Eight (17.0%) of the 47 HGV-positive recipients and 48 (16.9%) of the 284 HGV-negative recipients had a serum alanine aminotransferase level higher than the upper limit of normal (nonsignificant difference). The medical history of HGV-positive donors failed to reveal a particular at-risk event. The large majority of HGV-infected patients had a normal serum alanine aminotransferase level, and the proportion of patients with elevated alanine aminotransferase was the same in HGV-positive and in HGV-negative recipients. CONCLUSION: The pathological significance of HGV infection remains unelucidated, and the classification of HGV as a new hepatitis virus was perhaps premature.

Adult↗