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Biomedical subjects

P Madoz

Publications and source records attributed to P Madoz.

At least 37 records · Page 2Linked to original sources
PubMed1995

Efficacy of screening donors for antibodies to the hepatitis C virus to prevent transfusion-associated hepatitis: final report of a prospective trial.

Routine screening of blood donors for anti-hepatitis C virus (HCV) has been implemented in most developed countries. However, the independent efficacy of such screening has not been established in a controlled, prospective study. We tracked 478 patients transfused with anti-HCV-negative blood by first-generation enzyme-linked immunoassay (EIA) between July 1989 and May 1990 and compared the incidence of transfusion-associated hepatitis and HCV infections with that found among 280 patients transfused with blood unscreened for anti-HCV during the immediately preceding year. Of the 280 patients who had received transfusions before donors were screened for anti-HCV, 27 (9.6%) developed posttransfusion hepatitis and 1 additional patient seroconverted to anti-HCV without evidence of hepatitis, for a risk of posttransfusion HCV infection of 10.7% (28 of 262 recipients seronegative for anti-HCV before transfusion). Of the 478 patients transfused after July 1989 with blood screened for anti-HCV, only 9 (1.9%) developed posttransfusion hepatitis for a risk reduction of 80%. Seven of the 9 residual cases of hepatitis were caused by HCV (7 of 456 recipients seronegative before transfusion or 1.5%) for a risk reduction of transfusion-associated HCV infection of 86%. In retrospect, an anti-HCV positive donor was detected by second-generation immunoassay in 4 (57%) of the 7 HCV cases from the study cohort and in 19 of the 23 (83%) cases from whom all donor samples were available for testing in the historical cohort. No additional infectious donors were detected by third-generation immunoassay or serum HCV-RNA by polymerase chain reaction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Prevalence of thyroid autoantibodies is not increased in blood donors with hepatitis C virus infection.

Serum autoimmune reactions are found in many patients with hepatitis C. A high prevalence of thyroid dysfunction and antithyroid antibodies in patients with chronic hepatitis C was recently reported. We have compared the prevalence of thyroid dysfunction and antithyroid peroxidase antibodies in blood donors with hepatitis C virus (HCV) infection (study group) and in seronegative anti-HCV donors (control group). One hundred and ninety-two blood donors were studied: 96 were anti-HCV positive by ELISA 2 (48 males and 48 females; age 48 +/- 12.9 years, mean +/- SD), and 96 were HCV seronegative (55 males and 41 females; age 37 +/- 14.8 years). In all patients, serum TSH (0.25-4.2 mU/l) and fT4 (9-23 pmol/l) were measured by immunochemiluminiscent assays and antithyroid peroxidase antibodies (normal < 100 U/ml) by RIA. In all anti-HCV positive donors, hepatitis C viremia was tested using the nested polymerase chain reaction. Thyroid dysfunction was found in three females (3.1%) in the anti-HCV positive group (three cases of hypothyroidism), and in four (4.1%) anti-HCV negative blood donors (three cases of hypothyroidism, two females and one male; one case of hyperthyroidism, a female), (p = NS). Antithyroid peroxidase antibody titers were above normal values in 5 (5.2%) anti-HCV positive individuals and in eight (8.3%) anti-HCV negative blood donors (p = NS). These results do not show an increase prevalence of thyroid dysfunction and antithyroid peroxidase antibodies in blood donors with HCV infection when compared with a control group.

Adult↗
PubMed1995

Comparative study of two high doses of lymphoblastoid interferon in the treatment of chronic hepatitis C: influence on the levels of ALT, viraemia and histologic activity.

Ninety consecutive patients with chronic hepatitis C were included in a randomized, uncontrolled trial to compare the efficacy of two treatment regimens, 10 MU (group A) vs 5 MU (group B), of lymphoblastoid interferon, in a step-down schedule for 24 weeks. All of the patients had antibodies against the hepatitis C virus, and all but one were HCV RNA positive in serum. The origin of the infection was attributed to blood transfusion in 30 patients and classified as sporadic in 60 patients. During treatment reduction in the ALT levels as well as the elimination of viraemia was observed in both treated groups, although these changes did not correlate significantly with the interferon dose. Nine months after the end of therapy, a sustained response was achieved in 13.6% (12/88) of the patients. Relapse in group B (87.5%) was significantly higher than in group A (59.1%). The percentage of cases which remained with undetectable HCV RNA was significantly higher for the sustained responders (66.7%) than for the non-responders (11.8%) and relapser patients (2.4%). Repeated liver biopsies showed an overall significant reduction of all the subindices of histological activity from patients with sustained response, except for fibrosis. In short: the 10 MU dosing regimen of lymphoblastoid interferon was as efficient as the 5 MU dose as it brought about a similar improvement in ALT levels, histological activity and elimination of viraemia, albeit 10 MU proved significantly more effective in the prevention of a relapse among the responders after 24 weeks therapy.

Adult↗
PubMed1995

Characterization of antibodies directed against platelet cryptantigens detected during the immunological study of 356 consecutive patients with presumed autoimmune thrombocytopenia (AITP).

Cryptic antigens are detected by antibodies present in a wide spectrum of patients with or without thrombocytopenia, and even in healthy individuals. They are produced for unknown reasons and do not react with antigens of native platelets, but only with altered platelets. Cryptantigen antibodies may not only result in spuriously low platelet counts, but also in 'falsely' positive tests for platelet antibodies. We report our experience in the characterization of the different types of antibodies directed against cryptantigens of platelets: EDTA-dependent antibodies, PFA-dependent antibodies, EDTA-PFA-dependent antibodies and cold agglutinins. These antibodies were detected in the course of the serological study of 37 patients from a group of 356 (10%) whose blood was sent to our laboratory for platelet antibody testing. Pseudothrombocytopenia was diagnosed in 24 cases. Twenty-one of these showed EDTA-dependent or EDTA-PFA-dependent platelet agglutination and three were due to the presence of cold agglutinins. In 13 patients the thrombocytopenia was genuine. Eleven of these presented EDTA-dependent or EDTA-PFA-dependent antibodies in their serum and in the two remaining cases PFA-dependent antibodies were found. Cryptantigen antibodies were also detected in 9 out of 228 (4%) blood donors who were used as healthy controls in the platelet immunofluorescence test. In the light of the results obtained we put forward some guidelines to detect the presence of these antibodies and establish an accurate serological and clinical diagnosis of the autoimmune thrombocytopenias.

Adolescent↗
PubMed1995

[Blood donors seropositive for type 1 human immunodeficiency virus (HIV-1). Epidemiologic characteristics and clinical course].

PURPOSES: To evaluate retrospectively the epidemiologic profile and clinical course of the HIV-positive voluntary blood donors in the Sant Pau's Hospital Blood Bank (Barcelona-Spain) between 1986 and 1993. PATIENTS AND METHODS: A total of 119,345 blood donors were studied, and fifty seven such cases were identified. Risk behavior, causes of failure of the pre-donation procedures and clinical stage were analyzed. A follow-up of their infection was performed by the Infectious Disease Unit. RESULTS: The mean age of 57 seropositive donors was 31 +/- 8 years. Prevalence of HIV-1 infection among donors was 0.48 per 1000. Forty four (77%) were male and 13 (23%) female. Forty three (75%) were first time donors while 14 (25%) were repeat donors. The causes for the failure of the self-deferral questionnaire were: 42 subjects did not consider that they had engaged in "risk" behavior, seven donors lied in order to know if they were HIV carriers and two cases were driven to donate due to social or family pressure. The distribution of these donors according to risk behaviour was: 30 (53%) heterosexual, 11 (20%) homosexual, 11 (20%) intravenous drug users and five (7%) with no identified risk. It was noted that HIV infection progressed more rapidly to AIDS in HIV - positive homosexual donors than in heterosexual subjects (p < 0.05). CONCLUSIONS: Heterosexual donors who maintain sexual contacts with different partners without prophylactic measures for HIV infection currently represent the highest risk group for transfusion-related HIV infection. Clinical evolution of HIV infection was faster and more devastating in the homosexual group than in the heterosexual group.

Adult↗
PubMed1994

Demonstration of HCV-RNA and HBV-DNA in the serum of HBsAg negative patients with hepatocellular carcinoma.

Forty patients with chronic liver disease and HCC were analyzed for infection with hepatitis C (HCV) and hepatitis B (HBV) viruses. All patients were negative for HBsAg, 16 were alcoholics, 6 had previous blood transfusions and 18 had sporadic chronic hepatitis. Antibodies to HCV were determined by EIA 2nd generation. HBV-DNA was detected by PCR using primers of the precore region. Analysis of HCV-RNA was done with nested PCR amplifying the 5' non-coding region of the HCV genome, using primers complementary to nucleotides 1-20 and 305-320 and nested primers complementary to nucleotides 21-31 and 271-286 of the HCV-J1. Anti-HCV were positive in 35/40 patients (87.5%). HCV-RNA was detected by PCR in 34 patients (85%) all of them positive for the anti-HCV. HCV-RNA was detected in 70.5% of the alcohol abusers, in 100% of patients with history of transfusion(s) and 94.1% of patients with cryptogenic chronic liver disease. HBV-DNA was detected in only 2 patients. In conclusion, there is a high rate of HCV and a low rate of HBV viremia detected by PCR in Spanish patients with HCC HBsAg negative. No patient without anti-HCV presents HCV-RNA. Our results suggest that persistent HCV replication may play a role in hepatic carcinogenesis, as HBV-DNA could be found in only 5% of our HCC patients.

Aged↗
PubMed1993

[Thrombocytopenia associated with human immunodeficiency virus infection. Immunologic study of 60 patients addicted to parenteral drugs].

BACKGROUND: The immunologic study of 60 intravenous drug addict patients who were seropositive for the human immunodeficiency virus (HIV) and who developed thrombocytopenia (TP) is reported with the aim of establishing the relation of possible pathogenic factors which may trigger this complication. METHODS: In all the patients the presence of antiplatelet antibodies was studied by direct and indirect immunofluorescence together with crypto-antibodies, immune complexes, lymphocytotoxic antibodies, antiphospholipid antibodies, immunoglobulins, lymphocytic populations and subpopulations and serology against different infectious agents. RESULTS: Antiplatelet antibodies were detected in 71% of the patients of which 50% corresponded to immunoglobulins of IgG class, 12% to IgM, 21% to IgG plus IgM, 7% IgM plus IgA, 5% to IgG plus IgA and 5% IgG plus IgM plus IgA. In these patients a characteristic membrane fluorescence pattern was observed in which the fluorescein is distributed forming a thick, hard point. In 3 patients EDTA dependent crypto-antibodies were detected which in one case determined pseudothrombocytopenia. The immune complexes were demonstrated in 50% of the cases. Other findings were: hypergammaglobulinemia (86%), decrease in the CD4 population (47%), CD4/CD8 ratio < 1 (71%), lymphocytotoxic antibodies (70%), antiphospholipid antibodies (60%), and seropositivity for cytomegalovirus (62%), Epstein-Barr virus (10%) and hepatitis B virus (anti-HBc 75%, HBsAg 33%). CONCLUSIONS: Thrombocytopenia associated to infection by the human immunodeficiency virus in intravenous drug addict patients is due to the concurrence of multiple factors. The relevance of each may vary according to the risk practice of the collective analysed and even within the same group of some individuals or others. The numerous serologic findings in these patients fundamentally express the existence of a chronic polyclonal stimulation of B cells which may be initiated by the action of the drug itself and which becomes aggravated during the course of the multiple acquired infections among which that due to the human immunodeficiency virus is of note.

Adult↗
PubMed1993

[Frequency of platelet alloantigens in the Spanish population].

PURPOSE: The aim of this study is to investigate the distribution and incidence of platelet alloantigens in Spain and to compare this frequency with that found in other populations. MATERIAL AND METHODS: Five hundred blood donors were phenotyped for the HPA-1a (Zwa), HPA-3a (Bak(a)), HPA-4a (Yukb/Pen(a)) y HPA-4b (Yuk(a)). One hundred of these donors were also phenotyped for the HPA-5a (Br(a)) antigen. Furthermore, we also phenotyped a group of 50 black individuals from a community of west African immigrants who live in the province of Barcelona. The typing of all the antigens except those of the HPA-5 system was carried out using the technique of Indirect Immunofluorescence. To type the antigens of the HPA-5 system the MAIPA technique was employed. RESULTS AND CONCLUSIONS: The incidence of the different platelet specific antigens in the Spanish population is, in general, the same as that detected in the other European countries and in the white population of the USA. In Europe and North America, the HPA-1a antigen is the most important of all owing to its involvement in alloimmune clinical disorders. In Asia, this role seems to be played by the HPA-4b antigen. Moreover, polymorphism for the HPA-1a allele does not seem to exist. The incidence of the HPA-5b (Br(a)) antigen in Spain, which is higher than that for France and Germany, suggests a high involvement of this antigen in our country in different alloimmune processes. The preliminary data obtained in a group of black west Africans suggest the absence on polymorphism for the HPA-1a allele and that the incidence of the remaining antigens is comparable to that of the Spanish population.

Africa, Western↗
PubMed1992

High-dose chemotherapy with bone marrow rescue for treatment of Hodgkin's disease.

Between December 1st 1984 and July 1st 1991, 20 patients, 11 males and 9 females, median age 36 years (range 14-54) with Hodgkin's disease were treated with high dose chemo-radiotherapy followed by autologous bone marrow rescue. At the time of autologous bone marrow transplantation, 8 patients were in complete remission, 9 in sensitive relapse and 3 were resistant to conventional treatments. There were 3 early procedure-related deaths: 1 cardiac failure due to cyclophosphamide treatment, 1 veno-occlusive disease, and 1 patient died from CMV interstitial pneumonitis, 4 months after ABMT. Of the 17 other patients, 15 are alive, 12 in complete remission, 2 in relapse and 1 patient is not evaluable due to short-follow-up follow-up. Disease free survival is 65% at 20 months with a follow-up of 60 months. There is a trend for a better disease-free survival in patients in complete remission at the time of autologous bone marrow transplantation vs patients in sensitive relapse, although it does not reach statistical significance (80% vs 37%).

Adolescent↗
PubMed1991

High rate of infectivity and liver disease in blood donors with antibodies to hepatitis C virus.

OBJECTIVE: To determine the epidemiologic, clinical, serologic, and histologic importance of antibodies to hepatitis C virus (anti-HCV) in blood donors. DESIGN: Cross-sectional identification and prospective evaluation of seropositive donors; retrospective assessment of infectivity; and nested case-control study for risk factors. SETTING: Liver unit of a referral-based university hospital. SUBJECTS: Of 30,231 consecutive donors, 368 (1.2%) were found to be anti-HCV-reactive by enzyme-linked immunosorbent assay (ELISA). Two hundred and fifty-four of these 368 donors were evaluated for risk factors by comparison with 284 age- and sex-matched controls. Eighty-six spouses of seropositive donors were also evaluated. MEASUREMENTS AND MAIN RESULTS: Twenty-four percent of the seropositive donors had a history of percutaneous exposure to blood. This rate increased to 45% when only those donors confirmed to be anti-HCV positive by a second-generation recombinant immunoblot assay (RIBA-2) were considered. A family history of liver disease (odds ratio, 2.8; 95% Cl, 1.6 to 4.8), previous blood transfusion (odds ratio, 6.1; 95% Cl, 3 to 12.5), and a history of tattooing or intravenous drug abuse (odds ratio, 8.4; 95% Cl, 2.3 to 31) were associated with anti-HCV seropositivity. An elevated alanine aminotransferase (ALT) level was found in 58% of the seropositive donors. Of the 150 donors tested, 104 (69%; Cl, 62% to 77%) were confirmed by RIBA-2 to be anti-HCV positive. Of the 105 donors who had a biopsy, 16% had normal histologic findings, 11% had minimal changes, 21% had chronic persistent hepatitis, 45% had chronic active hepatitis, and 7% had active cirrhosis. All 77 donors with RIBA-2-confirmed seropositivity had histologic abnormalities. Of 43 donors evaluated in an infectivity study, 82% were implicated in previous HCV transmission. Only 2.3% of the spouses were anti-HCV positive. The ELISA, RIBA-2, and ALT results correlated with infectivity and abnormal histologic findings. CONCLUSIONS: In our geographic area, almost 70% of donors who are anti-HCV positive by ELISA are confirmed to be positive by RIBA-2; most of these donors appear to be chronic carriers of HCV and have substantial liver disease.

Adolescent↗
PubMed1991

Infantile spasms treated with high doses of sodium valproate: initial response and follow-up.

A long-term follow-up study of 42 patients with West syndrome treated with high doses of sodium valproate is presented. Control of the hypsarrhythmic EEG pattern was achieved after two weeks for over three-quarters of the patients with sodium valproate doses of 100 to 300mg/kg/day. Recurrence of hypsarrhythmia was observed most often in patients treated with doses lower than 200mg/kg/day. Other types of seizures appeared in half of the patients followed beyond two years of age. Monotherapy throughout follow-up was possible for 30 patients. Autism occurred in only one infant, and 12 achieved normal mental status. The most common side-effects were asymptomatic thrombocytopenia, vomiting and mild somnolence. Hepatic enzymes were not altered.

Cerebral Cortex↗