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C Fretz

Publications and source records attributed to C Fretz.

At least 19 recordsLinked to original sources
PubMed2003

[Self assessment tools].

Self assessment tools are an integral part of quality process and are involved in developing a quality assurance program. Improvements is becoming a necessity for the new international standards Iso 9001. After the evaluation of the situation and the measure of the results, the improvement developing program results from self assessment. This article intends to provide a better understanding of self assessment processing. The first part presents the technique used for the elaboration of the questionnaire in relation with 'good transfusion practices' and the tools used to identify opportunities for quality improvement. The involvement of the whole staff is the key for the efficiency of appropriate action. The second part presents how these tools can be applied in blood transfusion organisation and in some specific applications.

Blood Banks↗
PubMed2002

Hierarchical versus parallel processing in tactile object recognition: a behavioural-neuroanatomical study of aperceptive tactile agnosia.

The organization of the normal perceptual processing subserving tactile object recognition is poorly understood. While perceptual deficits associated with cases of tactile agnosia may pinpoint sites of critical interference with normal tactile information processing, the precise character of such deficits remains unclear. The aim of the present study was to explore the behavioural and neuroanatomical correlates of perceptual disturbances in two cases of unilateral aperceptive tactile agnosia. Perception of microgeometrical and macrogeometrical features was tested using an alternative forced choice paradigm. While both patients were impaired in the assessment of microgeometrical properties of objects (i.e. detecting subtle differences in grating profiles), one patient showed an additional deficit in the perception of macrogeometrical properties of objects (i.e. detecting differences in length of cuboids). The pattern of perceptual deficits for both patients suggested a severely compromised (if not totally lost) ability to recognize everyday objects. Perceptual performance improved when the patients had complementary tactile information (i.e. for intramodal comparison), despite a persistent inability to explicitly name the objects. That is, the patients were able to recognize objects, but only implicitly. Improved perceptual performance was also observed when complementary visual information was available (i.e. transmodal information transfer). In this case, the perceptual improvement was accompanied by a corresponding improvement in explicit object recognition. High resolution MRIs identified lesions in the postcentral gyrus in both patients, and additionally in the secondary somatosensory area (SII) and the posterior parietal cortex in the more severely affected patient. The results demonstrate that the underlying failure in tactile agnosia is mainly impaired perception of microgeometrical properties of objects due to a lesion of primary sensory cortex. The related neuroanatomical findings suggest a degradation of serial information processing within postcentral gyrus. In one case tactile agnosia was almost complete due to additionally impaired perception of macrogeometrical properties of objects, which correlated with the extension of lesion to the posterior parietal cortex. Importantly, the findings indicate traces of two distributed networks for tactile information processing and the associated parallel processing of complementary micro- and macrogeometrical information within postcentral gyrus and posterior parietal lobe.

Adult↗
PubMed2000

Hepatitis virus infections in heart transplant recipients: epidemiology, natural history, characteristics, and impact on survival.

BACKGROUND & AIMS: We have observed a high prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in heart transplant recipients (HTRs). The aim of this study was to assess the epidemiology, natural history, and clinical and biological characteristics of viral hepatitis in HTRs. METHODS: From 1983 to 1992, 874 patients underwent heart transplantation at the Pitié-Salpêtrière Hospital, Paris, France, 459 of whom qualified for analysis. A total of 140 patients had posttransplantation hepatitis B, C, or non-A-E. Sixty-nine patients developed HBV infection, 49 HCV infection, 11 HBV-HCV coinfection, and 11 non-A-E hepatitis. RESULTS: HBV was transmitted nosocomially from patient to patient, most likely during endomyocardial biopsies. HCV was mainly transmitted through blood transfusions or the transplanted organ. Clinical and biological findings after 2 years of follow-up showed that 3 patients with an HBV genotype A precore mutant had severe or subfulminant hepatitis and that patients with HBV and HCV infection always progressed to chronicity. In general, patients had mild alanine aminotransferase level increases, a high level of viral replication, and few severe histologic lesions, except for patients infected by precore HBV mutants. Patients coinfected by HBV and HCV tended to have more severe liver lesions. The survival rate 5 years after transplantation in patients with viral hepatitis (HBV, 81%; HCV, 89%; HBV and HCV coinfection, 100%; non-A-E hepatitis, 73%) was similar to that in patients without liver test abnormalities (76%). The actuarial survival curve was also similar in patients with or without liver test abnormalities. CONCLUSIONS: In our experience, histologic liver lesions do not progress rapidly in patients with post-heart transplant infection caused by HBV or HCV. HBV or HCV infection seems to have little impact on the 5-year survival rate of HTRs.

Adolescent↗
PubMed1999

[Recurrent retrobulbar neuritis and extensive myelitis: MS or optic neuromyelitis?].

Two female patients with recurrent optic neuritis and severe myelitis were described. In the first patient the illness began with recurrent myelitis, in the second one with optic neuritis. In both patients spinal MRI showed extensive enhancing lesions of the cervical respectively thoracic spinal cord. An initial cranial MRI was normal. In the first patient an MRJ demonstrated after several years lesions not typical for multiple sclerosis. In both patients cerebrospinal fluid showed especially mononuclear pleocytosis with cell counts between 11 and 126/microliter and severely elevated total protein, while intrathecal oligoclonal bands were not found. During exacerbations in both patients ENA-autoantibody-screening was positive. Intravenous treatment with methylprednisolone improved the clinical situation for some time. In both patients cyclophosphamide at a dose of 100 mg daily had to be given due to relapsing neurological deficits.

Adult↗
PubMed1999

Impact of hepatitis B and C virus on kidney transplantation outcome.

The impact of hepatitis B (HBV) and C (HCV) on patient survival after kidney transplantation is controversial. The aims of this study were (1) to assess the independent prognostic values of HBsAg and anti-HCV in a large renal transplant population, (2) to compare infected patients with noninfected patients matched for factors possibly associated with graft and patient survival, and (3) to assess the prognostic value of biopsy-proven cirrhosis. Eight hundred thirty-four transplanted patients were included: 128 with positive HBsAg (group I), 216 with positive anti-HCV (group II), and 490 without serological markers of HBV and HCV (group III). Fifteen percent and 29% of patients were HBsAg-positive and anti-HCV-positive, respectively. Ten-year survivals of group I (55 +/- 6%) and group II (65 +/- 5%) were significantly lower than survival of group III (80 +/- 3%, P <.001). At 10 years, among overall patients with HCV screening (n = 834), four variables had independent prognostic values in patient survival: age at transplantation (P <.0001), year of transplantation (P =.02), biopsy-proven cirrhosis (P =.03), and presence of HCV antibodies (P =.02). In the case control study, comparison of infected patients with their matched control patients showed that age at transplantation (P <.05), HBsAg (P =.005), and anti-HCV (P =.005) were independent prognostic factors. HCV, biopsy-proven cirrhosis, and age are independent prognostic factors of 10-year survival in patients with kidney grafts. The case-control study showed that anti-HCV and HBsAg were independently associated with patient and graft survivals. In infected patients, a routine liver histological analysis would improve selection of patients for renal transplantation.

Adult↗
PubMed1999

Atypical herpes simplex encephalitis presenting as operculum syndrome.

This case report demonstrates the course of herpes simplex virus cerebritis in a patient aged 7 years 2 months who presented with non-specific symptoms followed by an epileptic attack. Subcortical, bilateral opercular and bilateral thalamic lesions were detected, but the temporal and inferior frontal lobes were spared. The patient developed anarthria, impairment of mastication and swallowing consistent with operculum syndrome. Diagnosis was made by magnetic resonance imaging and elevation of oligoclonal antibodies specific to herpes simplex virus in cerebrospinal fluid after an unexpectedly negative polymerase chain reaction test.

Antibodies, Viral↗
PubMed1999

Posttransplantation cytotoxic immunoglobulin G is associated with a high rate of acute allograft dysfunctions in heart transplant recipients.

BACKGROUND: The significance of anti-human leukocyte antigen immunoglobin G (IgG) detected in the posttransplantation course of heart graft recipients remains unclear. METHOD: Sera from 121 cardiac allograft recipients transplanted between January 1992 and December 1994 were screened for the presence of lymphocytotoxic antibodies in the first year after transplantation. Dithiothreitol was used to differentiate IgG from immunoglobulin M. RESULTS: Nineteen patients (15%) had cytotoxic IgG develop, mainly during the first month after transplantation. The percentage of women was higher in this group (42% vs 15.7%; P <.05). Donor to recipient mismatches for sex, blood typing, cytomegalovirus serology, and human leukocyte antigen typing were comparable between IgG producers and nonproducers. The frequency of acute allograft dysfunction during the first year after transplantation was significantly higher among patients producing IgG (42% vs 5.9; P <.001). Most of these acute allograft dysfunctions were independent of cellular rejection lesions but were associated with a thickening of the posterior wall and the interventricular septum during the acute episode. Finally, all the patients but one recovered. Recurrences were not uncommon and, at 1 year after transplantation, the dose of cyclosporine used in patients producing IgG was significantly greater, as was the left ventricular thickness. CONCLUSION: Posttransplantation cytotoxic IgG is not uncommon and appears to be associated with a high rate of acute allograft dysfunction. Development of these antibodies can be caused by a previous undetected immunization, as suggested by the higher percentage of women in the producer group. Correlation with histologic lesions of humoral rejection are discussed.

Adolescent↗
PubMed1999

Neuroimaging findings in a patient recovering from global alexia to spelling dyslexia.

The authors report findings in a 67-year-old right-handed man who had an ischemic infarct in the territory of the left posterior cerebral artery. The clinical manifestation consisted mainly of total alexia without agraphia. The patient gradually recovered, subsequently showing the syndrome of spelling dyslexia. Cerebral MR-images revealed a circumscript infarction of medial and basal parts of left temporal lobe. In the acute stage [99mTc]HM-PAO SPECT was characterized by a diminished uptake in the definitely infarcted area and hyperfixation in the region of the left forceps major. Because high retention of HM-PAO indicates potentially salvageable tissue after an ischemic event, the depicted area might be correlated with the recovery of function. Thus, the authors' neuroimaging data give further support to the assumption that the left forceps major is a critical area for global alexia, whereas spelling dyslexia is due to involvement of the left medio-basal temporal lobe.

Aged↗
PubMed1998

[Acquired disorder of thirst perception with intact osmoregulation of vasopressin].

We report a 45 y old male patient with severe hypodipsia, but intact vasopressin secretion and maximal renal response to vasopressin. The patient presented during hot summer days, 18 months after a frontal lobe hemorrhage due to a ruptured aneurysm, with severe hypernatremia (171 mmol/L) and a plasma osmolality of 348 mosm/kg. He was awake and had no interest in fluid intake. After initial correction, a thirst test for 36 hours was performed. Plasma osmolality rose from 295 to 320, urine osmolality rose from 220 to 700 mosm/kg, while plasma vasopressin levels increased more than 3-fold. Throughout the test the patient did not exhibit appreciable thirst. The intact osmoregulation of vasopressin as evidenced by the plasma levels and the elicited renal response, indicates that a selective acquired disturbance of thirst is present. Whether the thirst center is destroyed or/and thirst recognition (frontal lobe affection) is disturbed primarily, can not be decided.

Aneurysm, Ruptured↗
PubMed1998

Evidence for high genetic diversity and long-term endemicity of hepatitis C virus genotypes 1 and 2 in West Africa.

During 1994 and 1995, the prevalence of hepatitis C virus (HCV) and its genotypes were studied in several rural and urban populations in three West African countries: Guinea, Burkina Faso, and Benin. The following groups were screened for antibodies to HCV (anti-HCV): 459 villagers in the forest region of Guinea; 965 individuals in urban, suburban, and rural populations of the Bobo Dioulasso area, Burkina Faso; and 582 blood donors in Cotonou, Benin. In Benin, 60 patients with sickle cell anemia (30 with and 30 without history of multiple transfusion) and 13 hospital patients with liver disease were also tested. RT-PCR detection of HCV-RNA was carried out on all anti-HCV positive samples, followed by genotyping and sequencing of unrecognized subtypes. The prevalence rates of anti-HCV were 1.1% in the Guinean population group, 1.4% among blood donors in Benin, and 4.9% in residents of Burkina Faso. In patients with sickle cell anemia, five of the 30 polytranfused patients (17%) had anti-HCV, whereas none of the patients without a history of blood transfusion had anti-HCV (P < 0.05). Among the 13 patients with liver disease, five had anti-HCV, of whom four had history of blood transfusion. HCV-RNA was detected in 41 anti-HCV positive sera. All belonged to genotypes 1 or 2, with a high genomic diversity; 18 different subtypes were identified, including 2c, 2d, and 16 new subtypes. Such genetic diversity poses a challenge for vaccine development and also implies that HCV infection is long-established in these West African regions.

Adolescent↗
PubMed1997

A case of Erdheim-Chester disease with orbital involvement.

The Erdheim-Chester disease is a rare idiopathic, systemic, histiocytic disorder. To our knowledge, ocular involvement has been reported in only 16 cases. We describe a 55-year-old man who had symmetrical exophthalmos and several skin nodules on the arms and trunk. A magnetic resonance imaging scan confirmed the presence of bilateral, intraconal, retrobulbar tumors. An examination of the histopathologic features of orbital and skin biopsy specimens revealed xanthogranulomatous infiltrate with Touton giant cells. Further systemic investigations showed bone and retroperitoneal involvement. Three years later, multiple eyelid xanthelasmas developed in the patient. These findings are consistent with the diagnosis of the Erdheim-Chester disease. The patient's condition is stable under therapy with low-dose corticosteroids. His survival is longer than usually described in the literature.

Bone Diseases↗
PubMed1996

Liver dysfunction in allogeneic bone marrow transplantation recipients.

Liver dysfunction is common in allogeneic bone marrow graft recipients, but no systematic studies of pre- and posttransplantation liver biopsies have been performed to identify and compare hepatic lesions. This study involved 25 consecutive patients who had undergone serial viral screening tests, liver tests, and pre- and posttransplantation liver biopsy. The aims were to ascertain the origin of liver disorders prior to bone marrow transplantation, to determine the mechanism and severity of liver dysfunction occurring early after transplantation, and to identify a possible relationship between pre-existing liver lesions and the frequency and nature of early liver dysfunction after transplantation. Pretransplantation biochemical liver tests were abnormal in 72% of patients, despite the absence of clinical liver disease. Eleven patients had chronic viral hepatitis B or C. Mild or moderate histological lesions were present in all the patients, with bile duct abnormalities in 48%, central vein abnormalities in 24%, sinusoidal fibrosis in 52%, portal fibrosis in 88%, portal necrosis in 52%, and parenchymal siderosis in 76%. After transplantation, fatal veno-occlusive disease occurred in two patients and biochemical abnormalities occurred in 24. Coded review of needle biopsy specimens failed to provide a single diagnosis. Histological lesions differed between pre- and posttransplantation biopsy specimens only by increased iron overload (96%, P<0.01). We conclude that pretransplant liver lesions contribute to hepatic dysfunction early after bone marrow transplantation, being very similar in nature and degree to lesions observed posttransplantation.

Adolescent↗
PubMed1996

[Why remove leukocytes from labile blood products in 1995?].

During the last 15 years, the techniques to prepare leukocyte-poor cellular blood components greatly improved, as well as our knowledge about the role of leukocytes in many adverse effects of transfusion. These two facts favor the extension of indication of leukocyte-poor blood components. Leukocytes in blood components may be detrimental to their storage, due to their metabolic needs and to their progressive lysis, leading to the release of cytokines. Leukocytes are the exclusive vector in blood of CMV and HTLV viruses. Leukocytes are a key element of the immune modifications induced by transfusion. HLA alloimmunization is favored by the transfusion of large quantities of leukocytes HLA different from the recipient whose immune functions are intact. Conversely, the risk of transfusion associated graft versus host disease is dependent of the transfusion of mature T lymphocytes sharing a partial identity with the recipient, and/or an immune deficient status of the recipient. Between these two extremes, many other effects related to the presence of leukocytes in cellular blood components, as are the transfusion effect observed in transplant recipients, the increased risk for bacterial infection after transfusion, the increased risk for tumor recurrence or the reactivation of virus infections, remain to be fully understood. Despite recent significant improvements, further studies, experimental as well as clinical, will be needed to expand the indications of leukocyte-poor blood components.

Bacterial Infections↗
PubMed1996

Hepatitis C virus (HCV) genotype analysis in apparently healthy anti-HCV-positive Parisian blood donors.

BACKGROUND: As only a few studies have examined the prevalence of various hepatitis C virus (HCV) subtypes in blood donors, information about the variability and route of infection in apparently healthy persons is limited. STUDY DESIGN AND METHODS: Blood donations collected at a large Parisian hospital (52,441) were investigated for antibodies to HCV. Serum samples were screened with an enzyme immunoassay. All HCV-positive donations were retested with a second enzyme immunoassay and confirmed by immunoblot. The HCV genotype was determined for all polymerase chain reaction-positive subjects. Untypable genotypes were sequenced in the NS5B region. RESULTS: In total, 83 (0.26%) blood donors were anti-HCV positive. Men (0.34%) were significantly more likely to be infected (p < 0.001) than women (0.19%). Prevalence rates in men between 20 and 39 years of age were higher than those in similar women (p = 0.01), but greater in women aged from 50 to 65 years (p = 0.05). Fifty-five sera were viremic, of which 49 could be genotyped by a line probe assay. One new HCV type 1 subtype and three new HCV type 2 subtypes were discovered. In total, 28, 10, 11, 5, and 1 serum samples were grouped into HCV types 1 through 5, respectively, involving a total of 13 subtypes. The mean age of HCV type 2-infected donors was 42 +/- 11 years, but that for type 3-infected subjects was only 30 +/- 4 years (p = 0.0048). Forty-nine subjects showed elevated alanine aminotransferase levels; 39 (80%) of these subjects were viremic (p < 0.05). CONCLUSION: Among the sampled population, an HCV prevalence rate of 0.26 percent was found, with the five most common European genotypes causing the infections. Four new subtypes were discovered. Correlation between genotype and risk factors was not apparent, but links with age, sex, and ethnic origin emerged.

Adult↗