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F Pinon

Publications and source records attributed to F Pinon.

At least 19 recordsLinked to original sources
PubMed2001

[Value of RHD fetal genotyping in the prevention of anti-D immunization].

Anti-D prophylaxis is currently applied in France after birth of an RhD positive infant, after interruption of pregnancy and after some antenatal immunizing events (amniocentesis...). However this program does not cover all the prenatal exposures to fetal RhD antigen, and maternal Rh immunization continues to occur. DNA RhD genotyping of the fetus is now reliably performed on amniotic fluid, and pre diagnostic studies on fetal DNA extracted from maternal plasma are promising. The widespread use of fetal RhD genotyping on maternal blood would allow the antenatal administration of Rh immunoglobuline in all Rh negative patients bearing an Rh positive fetus, insofar as it would preclude exposing the other Rh negative patients to the above plasma derived and rather expensive blood product.

Female↗
PubMed1998

How to stabilize the level of ionized calcium and citrate during plateletpheresis.

BACKGROUND AND OBJECTIVES: Citrate reactions are uncomfortable and potentially dangerous to apheresis donors. Reduction of citrate increases comfort, but may lead to platelet clumping. MATERIALS AND METHODS: We describe a protocol for stepwise reduction of the volume of ACD-A injected during plateletpheresis. This protocol has been carried out in 45 healthy donors with the Cobe 2997 (Cobe) cell separator, and in 35 with the Fenwal-CS 3000 (CS). RESULTS: Using this protocol, during the first hour of platelet collection, ionised calcium decreased on average by 18% for CS and by 18.4% for Cobe. During the second hour, Ca2+ and citrate ion concentration did not change with either Cobe or CS (about 65% of citrate ion load is eliminated). We observed mild signs of neuromuscular hyperexcitability in only 22% and 28% of donors with Cobe and CS, respectively. We also found a significant reduction of phosphate ions (p < 0.0001) at the end of the procedures. CONCLUSIONS: With this stepdown citrate reduction protocol, we obtained a significant reduction of injected citrate without the complication of platelet clumps.

Blood Proteins↗
PubMed1992

Transmission of HIV by transfusion of HIV-screened blood: the value of a national register. The 'Recipients' Study Group of the French Society of Blood Transfusion.

A National Register of transfusion-transmitted infections was opened by the French Society of Blood Transfusion on 1 October, 1986. Out of 54 initially reported cases of HIV-infection, allegedly transmitted by blood components, further investigation could be completed in 33 cases. The transfusional origin of contamination was considered as established or probable in 28/33 cases, either because a potentially infectious unit was identified among those transfused to the recipient (23/28), or because the recipient was known to be seronegative before transfusion (5/28), or both (10/28). In 5/33 cases transfusion was considered as presumably responsible for contamination because no other risk factor was found in the recipient. Among the 33 documented cases of HIV-transmission by screened blood, 29 (88%) occurred between 1985 and 1987, and four (12%) during 1988. Out of 19 implicated donors later found seropositive, 16 belonged to a high-risk group for HIV-infection. The majority of HIV-infections occurred as a consequence of blood donation in the window period between contamination and the appearance of detectable antibodies in the donor's serum (11/19). In three instances, however, human and operational errors led to the release of seropositive units. We conclude that the main value of this Register is to provide a potential trend-indicator of transfusion-related infectious risks, to allow objective documentation of reported cases and to contribute to the improvement of blood transfusion practice.

AIDS Serodiagnosis↗
PubMed1991

[Prevention of perinatal hepatitis B virus transmission. Epidemiology and cost/efficacy ratio in the Paris region].

The HBs antigen (AgHBs) was detected in 152 out of 6605 (2.3 percent) pregnant women who attended four representative maternity clinics in the Paris region. In 98 percent of the cases this finding reflected chronic hepatitis B virus infection. Among women born outside France (47 percent of the women tested, 79 percent of the AgHBs positive women), the relative risk was 6 for Asiatics, 5.5 for Africans and 4 for French women born in overseas departments or territories. Whatever the women's geographical origin, studies of their medical history revealed no significant difference between AgHBs positivity and AgHBs negativity. Overcrowding and multiparity correlated globally with the presence of AgHBs, but this correlation was absent in French women born in France. In non-African and non-Asiatic women detection guided by medical and socio-familial criteria would not be efficacious. The authors recommend systematic detection of AgHBs in pregnant women and estimate at about 180,000 french francs the cost of prevention for each case evolving toward the vital complications of chronic hepatitis B virus infection, an outcome which in the long term may affect 600 individuals born each year and who had contracted the infection during the perinatal period.

Adult↗
PubMed1991

[The perinatal transmission of the hepatitis B virus in the Paris area].

HBsAg was detected in 152 pregnant women among 6,605 (2.3%) screened in the prenatal clinics of four hospitals representative of the Paris metropolitan area. In 98% of cases, HBsAg positivity indicated chronic HBV carrier status. Among patients born out of continental France (47% of screened women, 79% of positive women) relative risk of chronic infection was 6 in Asians, 5.5 in Africans, and 4 in French women born in non-continental France. No significant difference in medical history was seen between HBsAg-positive and HBsAg-negative patients, in any of the birthplace groups. In women born out of continental France, number of children and crowding in the home were correlated with HBsAg-positivity; these correlations were not found in French women born in continental France. In non-African, non-Asian women, screening on the basis of medical, social and familial criteria (simulated in this study) would not be effective. Routine screening for HBsAg in pregnancy is advocated. The cost of the prevention of each case of perinatally acquired chronic HBV infection by routine screening followed by prophylactic treatment of a risk neonates was estimated at 180,000 French Francs (35,000 dollars). This approach is the only means of preventing the long-term life-threatening complications of chronic HBV infection in the 600 neonates born each year in France to HBsAg-positive mothers.

Africa↗
PubMed1991

[Perinatal transmission of the hepatitis B virus in Paris region].

HBsAg was detected in 152 pregnant women among 6,605 (2.3%) screened in the prenatal clinics of four hospitals representative of the Paris metropolitan area. In 98% of cases, HBsAg positivity indicated chronic HBV carrier status. Among patients born out of continental France (47% of screened women, 79% of positive women) relative risk of chronic infection was 6 in Asians, 5.5 in Africans, and 4 in French women born in non-continental France. No significant difference in medical history was seen between HBsAg-positive and HBsAg-negative patients, in any of the birthplace groups. In women born out of continental France, number of children and crowding of the home were correlated with HBsAg-positivity; these correlations were not found in French women born in continental France. In non-African, non-Asian women, screening on the basis of medical, social and familial criteria (simulated in this study) would not be effective. Routine screening for HBsAg in pregnancy is advocated. The cost of the prevention of each case of perinatally acquired chronic HBV infection by routine screening followed by prophylactic treatment of at risk neonates was estimated at 180,000 French Francs (35,000 dollars). This approach is the only means of preventing the long-term life-threatening complications of chronic HBV infection in the 600 neonates born each year in France to HBsAg-positive mothers.

Female↗
PubMed1989

[Preparation of maternal platelets collected by separator for use in fetal transfusion in a case of alloimmunization by anti-PLA1].

In one case of fetal thrombocytopenia due to maternal immunization against PLA1 fetal platelet antigen, maternal platelets were collected by automated plasmapheresis. The platelets were collected 24 hours before fetal transfusion at 28, 29, 31 and 36 weeks of gestation. The maternal platelets were irradiated and concentrated in a small volume (7.10(10) to 1,4.10(11) plts in less than 20 ml maternal plasma) a few hours before transfusion. When prepared as described, maximal and irreversible platelet aggregation is obtained with 20 microM of ADP and the pH is over 6, 5-6 hours after concentration. The amounts of transfused platelets were determined to increase theoretically fetal platelet counts over 200,000 plts/mm3. The fetal platelet counts, determined immediately after transfusion, showed an increase of 100,000 plts/mm3. Prenatal fetal transfusion of maternal platelets is available to avoid fetal bleeding during delivery, and during the early neonatal period.

Adult↗
PubMed1984

HLA-DR locus and maternal-foetal relation.

Antigen HLA-A, B sharing couples have been previously observed in abnormal pregnancies of unknown etiology. We have determined the HLA-A, B, C and DR antigens of 20 couples with recurrent spontaneous abortions (RSAs), 32 control couples and 100 normal controls. The results showed that in couples with more than two idiopathic repeated abortions, there is no significant increase in the HLA antigen sharing couples. But we were able to observe, in the affected couples, a significant increase in HLA-DR antigen sharing as regards the control couples. We also find a significant increase in the DR5 antigen, in both wives and husbands, in couples with repeated abortions of unknown etiology as previously described for the Dw5 antigen.

Abortion, Habitual↗
PubMed1981

[Anti-erythrocyte immunization in the pregnant woman. Apropos of the analysis of 761 cases of alloimmunized women delivered in the Paris area in 1978 and 1979].

Through analysis of 760 cases of allo-immunized women delivered in the Paris area during 1978 and 1979, anti-erythrocyte immunization (ABO excluded) still appears to be a consequent perinatal risk, for the mother as for her fetus. During the considered period, general incidence in the parisian population has been of 3,78 for 1 000 livebirths, one out of four cases being a "non Rh D"immunization. Obviously, anti-D immunoglobulin prophylaxis has not proved to be as efficient as it promised to be, after more than ten years of application. Taking into account cases affecting "non ordinary" residents in the observed area, incidence of anti-D immunizations was of two out of a thousand. Anti-D immunoglobulin actual efficiency cannot be incriminated, for when correctly applied Rhesus immunization prophylaxis has demonstrated its ability to induce a twenty-fold reduction of immunization risk due to pregnancy. It must be pointed out, unfortunately, that most cases of undue immunizations are related to prophylatic omissions after delivery, miscarriage, abortion or fortuitous hetero-Rhesus blood transfusion. On another hand an important increase of "non Rh D" immunizations, which incidence, if one images that unknown cases are as frequent as known cases, could be two out of a thousand deliveries, is perhaps able to neutralize partially the decrease of Rh D immunizations. Though is underlined the absolute necessity to extend systematically anti-erythrocyte antibody screenings to all pregnant women, whatever the blood group is. A great variety of antibodies specificities can be found among "on Rh D" immunizations but anti-Kell and anti-c are by far the most frequently met. In most cases theses immunizations could easily be avoided, assessing that all female subjects aged less than 50 years are only given Kell negative and, if lacking c antigen, CC phenotyped blood.

Antibodies, Anti-Idiotypic↗
PubMed1975

[Fetomaternal hemorrhages and their importance in perinatal pathology].

Transplacental haemorrhage is usually studied as an aspect of Rh immunisation prevention. In this paper the authors emphasize importance of this syndrome in noe-natology, as massive transplacental blood loss may result in severe foetal and neo-natal anemia or even lead to intra uterine death. Different technics for evidencing the presence of fetal cells in the mother's circulation are first discussed, the acid elution method appearing to be the easiest and fastest one. Results of nearly 40.000 Kleihauer's tests screening routinely performed in Paris at the time of delivery, are reported. The much higher frequency of very large transplacental haemorrhage is pointed out in cases of stillbirth. On a practical point of view, routine testing for transplacental haemorrhage finds its major interest in Rh prevention. A formula is proposed by one of the authors to calculate the most accurate dose of passive anti-D antibody in relation with quantitation of fetal haemorrhage. At last the autors attempt a new approach to the problem of neonatal unexplained anemias. Two different types of fetal bleeding are postulated, either chronic associated with haematologic signs of regeneration, or massive at the time of delivery without haematologic symptomatology. These condtions could lead to two different clinical pictures, either hydropsfetalis when chronic, or hypovolemic schock when massive and immediate.

Anemia↗
PubMed1975

[Frequency and importance of fetomaternal hemorrhages through early amniocentesis].

Amniocentesis is a technic to which it is now made more and more reference, even when feto-maternal incompatibility is not involved, for many various indications and at variable chronology along pregnancy. Our study concerns the risk developing Rh immunization among Rh negative women, undergoing amniocentesis early in pregnancy. 233 women had 243 amniocentesis between 16 and 21 weeks of pregnancy. Fetal cells in the maternal circulation were searched for using the Kleihauer's acid elution technic. In 154 cases, the Kleihauer's method was also used just before the amniocentesis, in order to run out a spontaneous foeto-maternal haemorrhage and to correlate the 25 (16,2%) transplacental haemorrhage reported to amniocentesis. When ever the result was positive, we observed a feto-maternal ratio varying from 1/20 000 to 100/20 000 but it is very difficult at this early period of fetal life to assure a precise volume of blood from this ratio. Placental localization preceeding amniocentesis does not seem minimizing the risk of bleeding. Althrough the occurence of a fetal bleeding seems to be more frequent in cases where blood can be demonstrated in the amniotic fluid (8/25 = 32%) than in cases it is not, the estimated volume of the foeto-maternal haemorrhage is not related to the presence or absence of blood in the amniotic cavity. In 3 cases the intra-amniotic blood was tested by the Kleihauer's method. In two instances there was a mixture of adult and fetal cells. In the 3rd case only fetal cells were present. In this last case, as in 17/25 bloody amniotic fluid (68%) no feto-maternal haemorrhage could be demonstrated. The risk of Rh immunization commands prophylaxis. In such Rh negative women, we inject intravenously a 85 mug dose of anti-D immunoglobulin, soon after performing amniocentesis, what ever the result of Kleihauer test is positive or negative.

Amniocentesis↗
PubMed1975

[Treatment of diabetic retinopathy by centripetal pan-retinal photocoagulation with the argon laser].

The argon laser is such an effective method of treating diabetic retinopathy that it is used in the early stages. The indications for treatment are related either to ophthalmoscopically visible lesion, or to lesions revealed by angiography, which is necessary each year in all diabetics. As for as technique goes, it is desirable to begin pan-retinal photocoagulation in the periphery so as to take advantage of the drying out of the related oedema secondary to the destruction of the retina.

Diabetic Retinopathy↗