RESUMEN
The treatment of chronic hepatitis C forms a considerable burden for society. The present standard treatment with PEG-Interferon and Ribavirin is costly, has side effects and is not always effective. The current trend is to prolong treatment from 24 to 48 or even 72 weeks in patients infected with genotypes 1 and 4 virus, in order to prevent relapses after cessation of therapy. There are, however, suggestions that treatment of relapses gives a response rate similar to that of first-time treatment. We, therefore, compared the sustained response rates and the mean treatment durations of one-time treatment and cyclic treatment in a model that incorporates the rates of non-response to antiviral therapy, of breakthrough during and of relapse after cessation of treatment. Our calculations show that, even under the most unfavourable assumptions, repeated 6-month treatment lowers the mean treatment duration from 9.6 to 7.5 months when compared to a single 12-month treatment, without jeopardising the overall effectiveness. If the results of our model calculations can be confirmed, current guidelines for the treatment of infections with genotype 1 hepatitis C virus ought to be reconsidered.
Asunto(s)
Hepatitis C/terapia , Antivirales/farmacología , Enfermedad Crónica , Humanos , Interferones/farmacología , Modelos Teóricos , Polietilenglicoles/química , Recurrencia , Ribavirina/farmacología , Factores de Tiempo , Resultado del TratamientoRESUMEN
Individuals may differ in their capacity to produce cytokines. Since cytokines play a key role in allograft rejection, we investigated whether inter-individual differences in cytokine production by in vitro stimulated PBMC are related to the occurrence of acute liver transplant rejection. Our study group comprised 49 liver transplant recipients and 30 healthy individuals. Rejection, which occurred within one month after liver transplantation, was defined in 22 patients ("rejectors") as biopsy-proven rejection, treated with high dose prednisolone. Patients who never experienced rejection episodes were termed as "nonrejectors" (n=27). PBMC of healthy individuals and of liver transplant recipients, collected late after transplantation (mean 3.5 years), were cultured in the presence and absence of Concanavalin A. The production of TNF-alpha, IFN-gamma, IL-10, and IL-13 was measured in supernatant after 1, 2, 3, 4, and 7 days of cell culture. In cell culture, stimulated PBMC of rejectors were found to produce significantly higher levels of TNF-alpha, while there was a trend towards higher production of IFN-gamma and IL-10 as compared to nonrejectors. After grouping patients into high or low cytokine producers based upon reference levels of the healthy individuals using multivariate analysis it was found that occurrence of acute liver transplant rejection correlated to high production of TNF-alpha and low production of IL-13. After stimulated cell culture PBMC of liver transplant recipients show a differential production of TNF-alpha and IL-13 which is correlated with the occurrence of acute liver transplant rejection.
Asunto(s)
Rechazo de Injerto , Interleucina-13/biosíntesis , Trasplante de Hígado/inmunología , Factor de Necrosis Tumoral alfa/biosíntesis , Enfermedad Aguda , Adulto , Anciano , Femenino , Prueba de Histocompatibilidad , Humanos , Interferón gamma/biosíntesis , Interleucina-10/biosíntesis , Masculino , Persona de Mediana EdadRESUMEN
The pharmacokinetics of cyclosporin after oral administration were studied in seven patients with non-end stage primary biliary cirrhosis (PBC) without previous cyclosporin treatment (Group I), a control group of nine patients with skin diseases (mainly psoriasis; Group II) and six patients with PBC after prolonged cyclosporin treatment (Group III). Whole blood concentrations of cyclosporin were measured using a non-specific (N) radioimmunoassay (RIA) and--in a majority of the cases--also by a RIA specific (S) for the parent drug. No difference in cyclosporin absorption was observed between patients with PBC and those with a skin disease. The mean values for the area under the blood concentration-time curve for the first 6 h after the test dose (AUC0-6) and the maximal blood concentrations (Cmax) were significantly higher for Group I compared with Group II patients (P = 0.007 and 0.03, respectively), but the time to maximal blood concentrations (tc,max) did not differ. There was a trend toward higher mean AUC0-6 (P = 0.08) and Cmax (P = 0.08) values for Group III compared with Group I patients. Tc,max values were not influenced by prolonged cyclosporin treatment. The ratio of cyclosporin whole blood concentrations measured by the non-specific and specific RIA's (N/S ratio) increased with time without obvious differences between the three groups. These data suggest that cyclosporin absorption and its biotransformation in the liver are not impaired in patients with non-end stage PBC and that neither is affected by prolonged treatment.
Asunto(s)
Ciclosporina/farmacocinética , Cirrosis Hepática Biliar/metabolismo , Enfermedades de la Piel/metabolismo , Administración Oral , Adulto , Anciano , Anticuerpos Monoclonales , Ciclosporina/administración & dosificación , Femenino , Humanos , Absorción Intestinal , Masculino , Persona de Mediana Edad , RadioinmunoensayoRESUMEN
Measurement of thyroid stimulating immunoglobulins (TSI) has not yet found widespread application in the diagnosis and management of Graves' disease. One of the problems is the poor and variable sensitivity of the different assays. We therefore studied the influence of the accessibility of the basal part of human thyroid epithelial cells in monolayer culture on their cAMP response to thyroid stimulating hormone (TSH) and TSI. Test media containing either ammoniumsulphate-precipitated globulin fractions of sera from normal controls and treated or untreated patients with Graves' disease or TSH were used to stimulate cAMP production by cryopreserved human thyroid epithelial cells in monolayer culture. Incubations with and without the use of porous membrane inserts as culture surface were compared by univariate parametric and non-parametric testing. It appears that more TSH-receptors, probably on the basal part of the thyrocyte, can be exposed to the medium by using a porous membrane as culture surface as demonstrated by the increased analytical sensitivity of the semi-bioassay of TSH and TSI.
Asunto(s)
AMP Cíclico/biosíntesis , Glándula Tiroides/metabolismo , Autoanticuerpos/inmunología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Epiteliales , Epitelio/inmunología , Epitelio/metabolismo , Humanos , Inmunoglobulinas Estimulantes de la Tiroides , Glándula Tiroides/citología , Glándula Tiroides/inmunología , Tirotropina/farmacologíaRESUMEN
In order to determine which factors predict the outcome of short term antithyroid drug treatment we studied 42 patients with diffuse goitre in whom 43 instances of thyrotoxicosis were treated. Treatment duration ranged from 24 to 61 wk (median 30 wk). All patients received high-dose carbimazole and thyroid hormone substitution. Patients in remission were followed for 39 to 134 wk (median 73 wk). The relapse rate at 1 yr and at 2 yr after cessation of antithyroid drug treatment was 51%. Of the parameters studied presence or absence of eye signs and initial serum levels of thyroxine, triiodothyronine and immunoglobulin-G in the relapse group and in the remission group showed significant differences in univariate analysis. No significant differences were found for age, sex, family history of thyroid disease, thyroid gland volume or TSH-receptor stimulating autoantibodies. Linear discriminant analysis shows that of the four remaining factors thyroxine is not important in separating both groups. Cox analysis yields only initial serum triiodothyronine and eye signs as significant prognostic factors. With these two factors 18 out of 23 predictions of remission and 16 out of 18 predictions of relapse in the 41 patients with known initial serum triiodothyronine concentrations are correct. Such predictions can be used in the choice of therapy, short-term medical treatment for patients with a low risk and long-term medical treatment or, at the appropriate time, a destructive form of therapy for patients with a high risk of relapse.
Asunto(s)
Enfermedad de Graves/tratamiento farmacológico , Hipertiroidismo , Análisis de Varianza , Carbimazol/uso terapéutico , Estudios de Seguimiento , Enfermedad de Graves/sangre , Humanos , Hipertiroidismo/sangre , Pronóstico , Recurrencia , Análisis de Regresión , Análisis de Supervivencia , Hormonas Tiroideas/sangreRESUMEN
In toxic nodular goitre relapses of hyperthyroidism after medical therapy probably are more common than in toxic diffuse goitre. It has also been reported that in patients with toxic diffuse goitre a high ratio of triiodothyronine (T3) and thyroxine (T4), initially or during medical treatment, predicts a relapse of the hyperthyroidism after cessation of therapy. We therefore studied the relationship between T3 and T4 in untreated patients with toxic diffuse goitres (n = 46, mean ratio T3/T4 29.6 nmol/mumol +/- 10.7 SD) and toxic nodular goitres (n = 12, ratio 29.3 +/- 17.1), and found no significant difference. Both groups differ significantly from normal controls (n = 16, ratio 14.6 +/- 1.5, P < 0.01). From the patients with toxic diffuse goitres we compared two groups. Patients in the first group remained in remission after short-term medical treatment (n = 10); the second group contains patients with a relapse of hyperthyroidism (n = 10). Differences between both groups in the median ratio of T3 and T4 were assessed before the start of treatment, at 4 and at 8 weeks. No significant differences were found between the two groups. The ratio of T3 and T4 is not helpful in distinguishing diffuse and multinodular toxic goitre or in determining the prognosis after medical treatment of hyperthyroidism caused by a hyperfunctioning thyroid gland. However, recurrence of hyperthyroidism was found in 3 patients with a T3/T4 ratio > 60 nmol/mumol after 8 weeks of treatment.
Asunto(s)
Bocio/sangre , Hipertiroidismo/sangre , Tiroxina/sangre , Triyodotironina/sangre , Adulto , Anciano , Estudios de Casos y Controles , Humanos , Persona de Mediana Edad , Análisis de RegresiónRESUMEN
BACKGROUND: A liver tumour is occasionally found by coincidence during upper abdominal imaging. The diagnostic and therapeutic strategy for incidental liver tumours is discussed. METHODS: Review of the literature. RESULTS: When a liver tumour is found by coincidence, the questions to be answered are whether a definite diagnosis can be reached by imaging alone, and whether treatment is indicated. To answer the first question we have to know the characteristics of the various liver tumours with different imaging techniques, and the added value of more invasive diagnostic procedures. For an answer to the second question, information on the natural course of the specific tumour and on the risks and benefit of treatment is required. Of course, the a priori chance of certain diagnoses depends on the presence or absence of risk factors. Using simple imaging techniques, liver lesions can be categorized as single or multiple and as cystic or solid. Cystic lesions are usually benign, either congenital or parasitic. Solid lesions can be benign or malignant. The most common benign lesions are haemangioma, focal nodular hyperplasia and hepatocellular adenoma. Malignant tumours arising in the normal liver can be primary, in the form of hepatocellular carcinoma, or secondary, resulting from dissemination of a primary tumour outside the liver. All these tumour types can present with typical features in various imaging studies. A definite diagnosis based on imaging alone, however, is not always possible. On the other hand, even histological examination of biopsy samples sometimes does not differentiate between benign and malignant tumours. In the case of an asymptomatic liver tumour the main indication for treatment is proven or suspected malignancy. Large adenomas form a notable exception, these should be removed if they are over 5 cm in diameter or when they grow during follow-up, especially during pregnancy. Therapy will usually consist of liver resection, either partial or, when this is not possible, complete resection followed by liver transplantation. An important caveat is that a surgical procedure without morbidity and mortality does not exist. For symptomatic benign liver tumours the options are the same, but there may be equally effective and less risky alternatives in specific cases, such as embolization for focal nodular hyperplasia and irradiation for haemangioma. CONCLUSION: The diagnostic and therapeutic approach to incidental liver tumours depends on several factors, including size, aspect and number of the tumours, the clinical background, the a priori chance of a certain type of tumour and especially the risk of malignancy.
Asunto(s)
Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Adenoma de Células Hepáticas/diagnóstico , Adenoma de Células Hepáticas/cirugía , Adenoma de Células Hepáticas/terapia , Diagnóstico Diferencial , Hiperplasia Nodular Focal/diagnóstico , Hiperplasia Nodular Focal/cirugía , Hiperplasia Nodular Focal/terapia , Hemangioma/diagnóstico , Hemangioma/cirugía , Hemangioma/terapia , Humanos , Neoplasias Hepáticas/cirugíaAsunto(s)
Hepatopatías/cirugía , Trasplante de Hígado/métodos , Enfermedad Aguda , Adulto , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Humanos , Masculino , PronósticoRESUMEN
There is no conclusive evidence that age influences the response to vaccination against hepatitis B virus. We therefore studied the immunogenicity of yeast-derived rHBsAg vaccine in elderly volunteers. The study was conducted in the outpatient clinics of an academic and a regional hospital, in a rural family practice and in an urban community centre. We recruited 112 healthy volunteers aged 59 years and over, to whom 10 or 20 micrograms yeast-derived HBsAg was given at 0, 1 and 6 months. Anti-HBs titres were measured by radioimmunoassay at 2, 6 and 7 months. Responders and non-responders were compared using univariate non-parametric tests and multivariate logistic regression analysis. Of the 116 subjects who volunteered to take part in the study, 106 vaccinees completed it. The percentage of subjects with an anti-HBs titre > or = 10 IU l-1 at 7 months was 60% (95% confidence interval: 51-70%; geometric mean titre; 253 IU l-1). Of the factors studied, i.e. setting, age, sex, alcohol consumption, current medication and vaccine dose, the use of medication at the time of the first vaccination was the only independent factor related to the response to vaccination, with a response rate of 78% (95% confidence interval: 66-89%) in those without medication. In elderly subjects, the proportion with protective concentrations of anti-HBs after vaccination with 10 or 20 micrograms yeast-derived recombinant HBsAg in a standard scheme is lower than in healthy adolescents. Within the older age group studied here, the use of medication, probably reflecting general health, is the only significant factor influencing the response to vaccination.
Asunto(s)
Antígenos de Superficie de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/inmunología , Vacunas Sintéticas/inmunología , Factores de Edad , Anciano , Femenino , Anticuerpos contra la Hepatitis B/sangre , Humanos , Masculino , Persona de Mediana Edad , VacunaciónRESUMEN
The central role of Thyroid Stimulating Immunoglobulins (TSI) in the pathogenesis of the hyperthyroidism of Graves' disease has become generally accepted and a wide variety of assays for the detection of these antibodies has been developed. The dependence on the availability of human thyroid tissue makes most of these assays unsuitable for routine clinical use, a problem circumvented by the use of nonhuman thyroid tissue in some TSI assays. We therefore compared porcine and human thyroid tissue in a TSI assay based on in vitro cAMP generation. No major differences in within and between run variation were found and, with some notable exceptions, a reasonable correlation could be demonstrated between the results in both assays (R = 0.89, P less than 0.001). However, the sensitivity of the porcine TSI assay is only 60% of the estimated sensitivity of the human TSI assay. In spite of the practical advantages this porcine TSI assay, and possibly also other TSI assays using non-human thyroid tissue, cannot totally replace human TSI assays. The value of these assays in predicting the outcome of medical treatment of Graves' disease remains to be established.
Asunto(s)
Inmunoglobulina G/análisis , Glándula Tiroides/inmunología , Animales , Bioensayo , AMP Cíclico/metabolismo , Bocio/inmunología , Humanos , Hipertiroidismo/inmunología , Inmunoglobulinas Estimulantes de la Tiroides , PorcinosRESUMEN
Hemolysis due to donor-derived B lymphocytes has been reported in patients who have undergone ABO-nonidentical orthotopic liver transplantation (OLT). Yet, until now, little was known about the management of this transplantation-induced hemolysis. In this report we describe our experience with hemolysis in a patient after OLT. In addition, based on theoretical assumption, we hypothesize that corticosteroids can be helpful in the management of ABO-nonidentical OLT-induced hemolysis.
Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Corticoesteroides/uso terapéutico , Anemia Hemolítica/etiología , Anticuerpos Antiidiotipos/inmunología , Incompatibilidad de Grupos Sanguíneos/etiología , Inmunosupresores/uso terapéutico , Trasplante de Hígado/efectos adversos , Traslado Adoptivo , Anemia Hemolítica/tratamiento farmacológico , Linfocitos B/inmunología , Linfocitos B/trasplante , Incompatibilidad de Grupos Sanguíneos/tratamiento farmacológico , Transfusión Sanguínea , Rechazo de Injerto/etiología , Rechazo de Injerto/prevención & control , Humanos , Hígado/citología , Hígado/inmunología , Trasplante de Hígado/inmunología , Masculino , Persona de Mediana Edad , Trasplante Homólogo/efectos adversosRESUMEN
A human monoclonal antibody type IgG4, designated 1Ff4, was obtained by Epstein Barr virus transformation of peripheral blood lymphocytes from a hepatitis B vaccinee (HB-VAX: plasma-derived vaccine) after one boost of yeast recombinant DNA derived vaccine (Engerix-B). 1Ff4 binds preferentially to HBsAg/adw(2) and HBsAg/ayw(1). In binding experiments, it competes with antibodies induced by vaccination with HB-VAX-DNA (yeast recombinant) and HB-VAX (plasma-derived vaccine). 1Ff4 competes in part with a monoclonal antibody for the w/r region. Partial inhibition of binding of HBsAg/adw(2) to solid phase anti-HBs was detected, resembling inhibition obtained using other human monoclonal specific for the "a"-loop. 1Ff4 does not bind to linear peptides covering the two "a"-loops or to an adw(2)/G145R mutant, its binding to wild type HBsAg strongly depends on the presence of disulphide bonds. In a large series of HBsAg-positive samples from an endemic area, 1Ff4 antibodies were successfully used to discriminate between an adw(2) and an adrq+ strain. The characterisation of 1Ff4 and other human monoclonal anti-HBs antibodies may help to understand the fine specificity of protective antibodies elicited by immunization.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Anticuerpos contra la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/inmunología , Vacunas contra Hepatitis B/inmunología , Hepatitis B/prevención & control , Vacunas Sintéticas/inmunología , Unión Competitiva , Epítopos de Linfocito B/inmunología , Humanos , Inmunización , Inmunización Secundaria , SolucionesRESUMEN
In this study, performed to assess the effect of auxiliary heterotopic liver transplantation on portal hypertension and hypersplenism, eight patients with chronic liver disease who underwent the procedure and had functioning grafts for at least 6 months were analyzed. The transplantation resulted in (a) normalization of platelet and leukocyte counts, (b) reduction of splenomegaly by 20% +/- 3% (P less than 0.02), (c) disappearance of ascites, and (d) diminution of esophageal varices in all patients. Intraoperatively, the mean portacaval pressure gradient decreased with 54% +/- 7% after recirculation of the graft (P less than 0.05). In conclusion, a functioning auxiliary heterotopic liver graft decompresses portal hypertension and reverses hypersplenism.
Asunto(s)
Hiperesplenismo/cirugía , Hipertensión Portal/cirugía , Trasplante de Hígado , Adulto , Antitrombina III/metabolismo , Ascitis/cirugía , Bilirrubina/sangre , Femenino , Humanos , Hiperesplenismo/etiología , Hipertensión Portal/etiología , Recuento de Leucocitos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/cirugía , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Albúmina Sérica/análisis , Trasplante HeterotópicoRESUMEN
Auxiliary heterotopic liver transplantation is theoretically attractive because it leaves the recipient's liver in place. The surgical trauma of hepatectomy is avoided, and failure of the graft does not necessarily lead to the death of the patient or a second, emergency transplantation. Another advantage is that matching the body sizes of the donor and the recipient is not mandatory, which increases the number of possible donors. However, previous clinical results of auxiliary liver transplantation have been poor. We performed auxiliary partial liver transplantation in six consecutive patients with end-stage chronic liver disease who were not accepted for orthotopic liver transplantation because they had massive ascites, deficient clotting function, cachexia, or poor pulmonary reserve. The donor liver was transplanted to the right subhepatic region after removal of segments II and III, and it was provided with portal and arterial blood. There were no major changes in hemodynamic measurements during surgery. The mean hospital stay after transplantation was 22.7 days (range, 14 to 29). After a mean follow-up period of 14 months (range, 5 to 23), all patients were alive, with good graft function as demonstrated by scintigraphy, Doppler ultrasonography, and synthesis of clotting factors. From these observations we conclude that auxiliary partial liver transplantation is an attractive alternative to orthotopic liver transplantation in high-risk patients. Its role in other patients who need liver transplants remains to be defined.