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1.
Five hundred thirty-three liver transplant recipients were seen for follow-up care over a 6-month period. Of these, 23 (4.3%) had a hemoglobin level of < or = 9 g/dl, with 19 being eligible for inclusion in this study. The median hemoglobin level was 8.7 g/dl. Two patients had iron-deficiency anemia. All of the patients were on therapeutic drugs which can suppress erythropoiesis or shorten the lifespan of mature erythrocytes. Six patients (31.6%) were viremic for human parvovirus B19 but none was B19 immunoglobulin M seropositive. Two patients were immunoglobulin M seropositive for cytomegalovirus. The patients with circulating B19 DNA were not easily distinguished from those without the virus by their laboratory results. The absence of reticulocyte counts for these patients contributed to this inability to differentiate B19 from other causes of anemia, particularly drug myelotoxicity. The high likelihood of making a specific diagnosis with the increasing availability of PCR should spur the search for this virus in the liver transplant population.  相似文献   

2.
Objective: To study parvovirus B19 infection in immunocompromised subjects such as renal transplantation recipients.
Methods: Two cases of B19 infection in renal transplant recipients have been included in the study. The outcome of the infection has been studied by both serologic and virologic methods. A monitoring of the DNAemia was done by a nested PCR in endpoint titration assays.
Results: In one patient with severe anemia an acute B19 infection was diagnosed by PCR 26 days after the transplant; a high level of DNAemia persisted until an intravenous immunoglobulin treatment. Then a sharp decrease of the DNAemia was shown, without full clearance of B19 virus. In a lymphocyte suspension from the organ donor, B19 DNA was detected. In the other patient, who recovered spontaneously from anemia, a persistent B19 infection was demonstrated at day 106 after transplantation and was still demonstrable after 470 days.
Conclusions: A high level of B19 DNAemia was associated with symptomatic infection, with severe anemia, whereas low-level DNAemia was long-lasting in asymptomatic subjects with impaired immunologic responses. The endpoint titration assay by nested PCR was very useful for the monitoring of B19 infection, particularly following the therapeutic intravenous immunoglobulin administration.  相似文献   

3.
4.
BACKGROUND: B19 virus infection with persistent anaemia has been reported in organ transplant recipients. Detection of B19 virus DNA in serum is the best direct marker of active infection. OBJECTIVE: The present study evaluated the incidence and clinical role of active B19 virus infection in renal transplant recipients presenting with anaemia. STUDY DESIGN: Forty-eight such recipients were investigated by nested PCR on serum samples. The controls were 21 recipients without anaemia. Active HCMV infection was also investigated as a marker of high immunosuppression. RESULTS AND CONCLUSIONS: In 11/48 (23%) patients B19 virus DNA was demonstrated in serum versus only 1/21 (5%) of the controls. Ten of these 11 patients had already been seropositive at transplantation and active infection occurred in eight of them during the first 3 months after transplantation. The remaining patient experienced a primary infection 9 months after transplantation. Eight (73%) of these 11 patients displayed a concomitant HCMV infection and four (36%) showed increasing serum creatinine levels but none developed glomerulopathy; 3/11 (27%) recovered spontaneously from anaemia whereas 8/11 (73%) needed therapy. In conclusion, the relatively high occurrence (23%) of B19 virus infection in patients presenting with anaemia, suggests that it should be considered in the differential diagnosis of persistent anaemia in renal transplant recipients. Presence of the viral DNA should be assessed early from transplantation and the viral load should be monitored to follow persistent infection and better understand the relation between active infection and occurrence of anaemia, and to assess the efficacy of IVIG therapy and/or immunosuppression reduction in clearing the virus.  相似文献   

5.
BackgroundHuman parvovirus B19 infection generally displays a self-limiting course followed by viral clearance; although, in some cases, persistent infection may occur. Few cases of severe pulmonary disease following primary infection in both immunocompetent and immunocompromised patients were reported.ObjectivesTo investigate the prevalence and clinical impact of parvovirus B19 in the lower respiratory tract.Study designThe prevalence of parvovirus B19-DNA was evaluated by Real-Time PCR in 264 bronchoalveolar lavages (BAL) from 189 adult patients over a full-year period and related to demographic characteristics, underlying pathologies, immune status, admission to intensive care unit, mortality within 28 days, and discharge diagnosis.ResultsParvovirus B19-DNA was detected in 7/189 (3.7%) patients, without significant association to demographic characteristics, immune status, transplant versus non-transplant status, admission to intensive care unit, presence of haematological conditions. In two lung transplant recipients surveillance specimens were positive to B19. Four of the remaining five patients presented respiratory insufficiency. A significant association to mortality was found, as 3/7 (42.9%) positive patients died within 28 days. No patient presented serological evidence of recent or acute infection and viremia.ConclusionsParvovirus B19 may be detected at low frequency in BAL specimens from patients with different pathological backgrounds. This finding could be due to chronic infection with virus persistence in the lower respiratory tract, also in the absence of symptoms unequivocally attributable to B19. The high rate of mortality warrants the need for further studies to evaluate the opportunity to consider parvovirus B19 in the diagnostic work-up of lower respiratory tract infections.  相似文献   

6.
BackgroundThere are no optimal diagnostic, treatment and post-infection surveillance strategies for parvovirus B19 infection in solid organ transplantation (SOT) recipients.MethodsWe conducted a retrospective review of all PVB19 infected cases confirmed by qPCR among SOT recipients at our institution over a 3-year period and reviewed the literature from 1990 to 2021.ResultsEight kidney and two heart transplant patients with refractory anemia had PVB19 infection. The viral DNA load in peripheral blood ranged from 2.62 × 102 to 8.31 × 106 copies/mL. Two patients with the lowest PVB19 DNA load only reduced the use of immunosuppressants and anemia was relieved. Eight received intravenous immunoglobulin (IVIG) (ranging from 0.25 to 0.5 g/kg/day). The median time to anemia improvement (hemoglobulin > 100 g/L) was 16 days (8–70 days) after treatment. One patient had a PVB19 relapse and viral DNA load > 1.00 × 108 copies/mL at diagnosis. A total of 86 studies involving 194 SOTs were screened from the literature, and the most common symptom was anemia and low reticulocyte count. PVB19 DNA was detected in all cases. Of that, 91.4% of cases received IVIG, 53.8% received IVIG and immunosuppression reduction, 6.5% of cases showed reduced immunosuppression without IVIG, and 2.1% did not receive any special treatment. The recurrence rate was 17.5%.ConclusionPVB19 infection is a cause of anemia after SOT, and treatment mainly relies on IVIG and/or immunosuppression reduction.  相似文献   

7.
Most of the viruses known to be associated with anemia in human tend to persistently infect their host and are noncytopathic or poorly cytopathic for blood cell progenitors. Infections with Epstein-Barr virus, cytomegalovirus, varicella-zoster virus, human herpes virus 6 (HHV-6), B19 parvovirus, human immunodeficiency virus, hepatitis A and C viruses and the putative viral agent associated with non-A-G post-hepatitis aplastic anemia have been reported in association with anemia. Nevertheless, a direct cytotoxic effect on erythroid progenitors has been clearly demonstrated only for human parvovirus B19 and evocated for HHV-6. A major role for destructive immunity is strongly suspected in the pathogenesis of anemia associated with the other viral infections. Host genes play a role in the occurrence of virus-induced anemia in animal models, and there are some evidences that genetic background could also influence the occurrence of virus-associated anemia in human.  相似文献   

8.
 To evaluate the occurrence and clinical role of active parvovirus B19 infection in solid organ and bone marrow transplant recipients, 256 serum samples from 212 transplant patients were investigated retrospectively by competitive polymerase chain reaction. Sera were drawn during the transplantation period and up to 6 months after transplantation during a nonepidemic 1-year period. Three patients were found positive for B19 DNA; only one liver transplant patient had a clinically overt B19 infection. Overall, the rate of active parvovirus B19 infection in transplant subjects was low (1.42%), probably due to the high number of actively or passively immunized subjects among transplant recipients; this may also account for the asymptomatic infections observed.  相似文献   

9.
Described for the first time in 1986, Parvovirus B19 (B19V) infection in kidney transplant recipients remains little‐known and probably underestimated. The aims of this study were to establish B19V infection frequency during the first year after kidney transplant and to determine predisposing factors and manifestations of the infection in renal transplant recipients. Sixty consecutive adult patients, transplanted less than a year before, were included in this study. B19V and other opportunistic viral infections were detected retrospectively in plasma samples collected every 15 days during the first 3 months and every month from 3 months to 1 year following the kidney transplant. Demographic characteristics, immunosuppressive treatment and biological findings were recorded on each sampling date. Six patients (10%) presented B19V viremia, while eight CMV (13.3%), seven EBV (11.7%), five HHV‐6 (8.3%), five BKV (8.3%), and two adenovirus (3.3%) infections were detected. The mean value of B19V viral load was 149 UI/ml. B19V infections were either reactivation or reinfection due to genotype two in five cases, while one case of primary infection with genotype 1 was observed. Neither risk factors nor biological consequences of B19V infection have been identified. These results rank B19V third among opportunistic viral infections occurring during the first year after a kidney transplant. With regard to this high incidence, and even if the risk factors and biological consequences of the infection should be assessed in larger studies, the question of systematic screening and follow‐up of B19V infection in kidney transplant recipients is relevant. J. Med. Virol. 85: 1115–1121, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

10.
Unselected intramuscular (IM) and intravenous (IV) immunoglobulins, as well as virus-specific hyperimmune globulins, occupy important roles as immunotherapy for viral infections. Standard IM immunoglobulins may be utilised in selected, susceptible patients for the prevention of hepatitis A and measles. Hyperimmune globulins to varicella zoster virus (VZV), hepatitis B virus and rabies have established indications for use as post-exposure prophylaxis. Cytomegalovirus (CMV) hyperimmune globulin has an indication for the prevention of primary CMV-associated disease in kidney transplantation and has been shown to decrease severe CMV-associated disease in liver transplantation. More recently, respiratory syncytial virus (RSV) hyperimmune globulin has been developed and is being utilised to prevent RSV disease in high risk infants and children during months of maximum risk for RSV infection. Unselected IV immunoglobulins (IVIg) have proven beneficial in preventing CMV-associated disease and graft-versus-host-disease in allogeneic bone marrow transplant recipients. In addition, IVIg plus ganciclovir is effective therapy for established CMV disease in both bone marrow and solid organ transplantation. IVIg for chronic anaemia associated with parvovirus B19 infection is gaining acceptance, as is the use of IVIg and intraventricular immunoglobulin for chronic meningoencephalitis associated with agammaglobulinaemia. Immunotherapy for the prevention or treatment of several other viral infections has been explored, but without clear conclusions. The use of human immunodeficiency virus (HIV) hyperimmune globulins in HIV-infected patients has yielded inconsistent results and the role of such therapy in the era of highly active antiretroviral therapy is uncertain. Oral immunoglobulins appear successful for rotaviral infections, but their exact use requires further clarification. Other immunotherapeutic modalities, such as monoclonal antibodies against CMV, RSV and HIV, have been developed but these agents have not undergone extensive clinical evaluation.  相似文献   

11.
Human cytomegalovirus (CMV) is a major cause of disease and transplant dysfunction in lung transplant recipients. Simultaneous emergence of more than one CMV-genotype can occur, and appears to be disadvantageous for the patient. In this study, the dynamics of individual CMV-genotypes in blood and lung was assessed within mixed CMV-genotype populations emerging after lung transplantation. In 69 plasma and 76 bronchoalveolar lavage samples of 16 lung transplant recipients with mixed CMV-genotype infections within the first year posttransplantation each of the major glycoprotein B (gB) and glycoprotein H (gH) genotypes was selectively quantified by genotype-specific quantitative TaqMan assays. The data obtained revealed that individually different genotype dynamics occurred for the individual patients and that the relative levels of the genotypes to each other may change over time. The quantitative development was independent of the specific gB-gH-genotype. In 10 of the 16 lung recipients the patient's individual genotype composition was the same in blood and lung. Genotype development during the follow-up was influenced by antiviral treatment. These data show for the first time that the CMV load used as diagnostic tool after transplantation is not always a constant entity but reflects the sum of the individual CMV-genotype dynamics developing over time.  相似文献   

12.
Persistent B19 parvovirus infection has been recognized in immunocompromised patients, often occurring with a low-titer viremia. In this study, nested polymerase chain reaction (PCR) for the detection of B19 parvovirus DNA was carried out on the sera of 49 human immunodeficiency virus (HIV)-1-seropositive patients, negative for the detection of B19 DNA at dot blot hybridization assay and with different values of serum anti- B19 IgM (27 patients proved positive and 22 negative). Of the 49 HIV-seropositive samples tested by nested PCR, seven were positive for the detection of B19 DNA. All seven belonged to the group of subjects seropositive for specific anti-B19 IgM. The study shows that, in the presence of specific B19 IgM, circulating virus may still be present but can be detected only by PCR. In that B19 infection can occur with low-titer viremia in immunocompromised patients, PCR may be the only method for virus detection. © 1993 Wiley-Liss, Inc.  相似文献   

13.
Long-term renal allograft survival in kidney transplant recipients infected by hepatitis C virus (HCV) may be influenced by the occurrence of de novo glomerulopathy associated with this virus. Therefore, we studied the evolution of HCV quasispecies in kidney transplant recipients infected by HCV with or without de novo glomerulopathy. The hypervariable region 1 (HVR-1) of the virus envelope was analyzed by cloning and sequencing 20 clones per sample to assess complexity and diversity from six kidney transplant patients who developed de novo glomerulopathy (group I) matched to six kidney transplant recipients without glomerular disease (group II), according to age, time since renal transplantation, and HCV genotype. Two sera were analyzed for each patient: one at the time of renal transplantation and the other at the time of appearance of de novo glomerulopathy, or after a similar duration since transplantation in group II. Overall, there was a significant increase of HCV viremia after the transplantation. This increase did not differ significantly between group I (+0.5 log copies/ml) and group II patients (+1 log copies/ml). The intersample diversity of HCV was similar in the two groups. Complexity and viral diversity were also similar at the time of transplantation. By contrast, complexity, diversity, and the proportion of nonsynonymous substitutions per nonsynonymous site were significantly higher after transplantation in group I patients. Our findings suggest a higher immune response and/or a particular cytokine production in patients developing de novo glomerulopathy rather than a direct effect of HCV on renal cells.  相似文献   

14.
Parvovirus B19 is the causative agent of erythema infectiosum in children, but the virus is associated with an increasing range of different diseases. These include acute and chronic arthritis, hydrops fetalis in pregnant women, aplastic anemia, and thrombocytopenia. The host's immune response is directed against the viral structural proteins VP1 and VP2. This study investigated the presence of IgG against the viral nonstructural protein NS1 using Western blot. Serum panels from healthy individuals, B19-infected pregnant women, and various disease groups were tested. The disease groups included patients with symptoms that may be linked to parvovirus B19 infection. The results showed that IgG against the NS1 protein was present in 22% of healthy individuals with past B19 infection. In cases of persistent or prolonged B19 infections, the prevalence of NS1-specific antibodies was as high as 80%. It is concluded that NS1-specific IgG may be used as an indicator of chronic or more severe courses of parvovirus B19 infections.  相似文献   

15.
In a prospective survey, all transplant patients at the hospital of the University of Zurich were screened for cytomegalovirus (CMV) infection. CMV infections were detected in a total of 40 of 104 transplant recipients; 31 could be diagnosed by CMV immunoglobulin M serology, 27 could be diagnosed by viremia, 11 could be diagnosed by antigenemia, and 13 could be diagnosed by the start of virus secretion. Combined application of serology and the detection of viremia showed the highest sensitivity (39 of 40 cases). Of the patients with severe clinical symptoms, six of seven had primary CMV infections caused by a positive transplant. Therefore, it is strongly indicated that patients with known risk factors should be regularly surveyed by a combination of methods.  相似文献   

16.
JC virus (JCV) rarely causes kidney disease, whereas BK virus (BKV) is a known cause of viral nephropathy. Existing studies on prevalence of JCV in healthy and transplanted subjects have reported only qualitative detection of viral DNA. We used quantitative PCR (qPCR) to assess JC viral load in transplant recipients and non-immunosuppressed controls, and compared JCV loads to BKV loads. JC viruria was seen in 8/23 (34.7%) controls, 23/103 (22.3%) renal, and 10/44 (22.7%) liver transplant patients. No patient developed JC viremia. BK viruria was seen in 2/23 (8.7%) controls, 36/103 (34.9%) renal, and 7/44 (15.9%) liver transplant patients. BK viremia was seen only in the kidney (8/103 = 7.7%) patients. The mean BKV urinary load was higher in kidney compared to liver patients and controls (4.22E + 07 vs. 2.88E + 05 vs. 4.39E + 02 copies/ml), whereas JC viral load was similar for all three patient groups (1.55E + 06 vs. 2.66E + 06 vs. 2.13E + 06 copies/ml). JCV viral loads were surprisingly high in all patient categories studied, but did not result in viremia or viral nephropathy. Although both BKV and JCV are widely latent in patients accepted for transplantation, concurrent reactivation of both viruses was infrequent. BKV viremia was seen in kidney but not liver recipients. The mechanisms underlying these notable phenomena remain to be investigated.  相似文献   

17.
Parvovirus B19 is the aetiological agent of one of the classical diseases of childhood, the rash illness fifth disease (erythema infectiosum). Beside this usually harmless illness parvovirus B19 was, however, found to be associated with a variety of severe diseases, mainly arthritis, anemia, thrombo- and granulocytopenia, hepatitis and myocarditis. In these cases parvovirus B19 may persist over long periods of time in the peripheral blood or in individual organs of the patients. During pregnancy B19-infections may result in spontaneous abortions, hydrops fetalis, and intrauterine fetal death. The detection of viral DNA and antibodies in the maternal serum and precise ultrasound surveillance of the allows an early diagnosis of the development of hydropic symptoms in the fetus. In most cases in time intrauterine blood transfusions result in the birth of sound children. Since about half of the young adults are not immunologically protected parvovirus B19-infections should be assumed as an important reason for virus-correlated problems during pregnancy. Based on these epidemiological data that were accumulated during the past years clinicians should pay more attention to B19-infections and the mode of viral transmission.  相似文献   

18.
Parvovirus B19 causes a variety of diseases in humans, with outcomes ranging from asymptomatic to severe, such as chronic anemia in immunocompromised patients or fetal hydrops and death after maternal infection during pregnancy. The virus may be transmitted via plasma-derived products. According to the results of solvent-detergent safety studies, an upper limit of B19 DNA in plasma pools was recently defined. To restrict the input of B19 virus into production pools, a quantitative nucleic acid test is a prerequisite. We examined the suitability of the two commercial quantitative B19 PCR tests, LightCycler-Parvovirus B19 quantification kit (Roche Diagnostics) and RealArt Parvo B19 LC PCR (Artus) for detection, quantification, and differentiation of the three known B19 genotypes, including the newly described erythrovirus variants (genotypes 2 and 3). The former kit was highly sensitive for genotype 1 but was not suitable for detection of genotype 2 or one of two genotype 3 strains. The latter kit detected and differentiated all three genotypes, albeit with lower sensitivity for one of the genotype-3 strains. We furthermore assessed the prevalence of the three B19 virus genotypes in blood donors, by screening pooled plasma samples derived from 140,160 Finnish blood-donor units. None of the pools contained detectable levels of B19 virus genotypes 2 or 3. The origin, mode of transmission, and clinical significance of these genotypes are unknown and deserve further study. The RealArt Parvo B19 LC PCR is suitable for detection, quantification, and differentiation of all three B19 virus genotypes in molecular and clinical research.  相似文献   

19.
Parvovirus B19 (B19V) can persist in immunocompetent symptomatic and non-symptomatic individuals, as demonstrated by the finding of viral DNA in different tissues, in absence of viremia and of anti-B19V IgM. The spread and the nature of this phenomenon have not been clearly determined. In order to investigate the frequency of persistence and the tissue distribution of the three genotypes of B19V, the viral load of the persistent virus and its expression in the affected tissues, 139 tissue samples and 102 sera from 139 asymptomatic individuals have been analyzed by consensus PCRs and genotype specific PCRs for B19V detection and genotyping. Viral load was measured by real time PCR and viral mRNAs were detected by RT-PCR. Altogether, 51% individuals carried B19V DNA, more frequently in solid tissues (65%) than in bone marrow (20%). Genotype 1 was found in 28% tissue samples, genotype 2 in 68% and genotype 3 in 3% only. Viral load ranged from less then 10 copies to 7 x 10(4) copies per 10(6) cells, with the exception of two samples of myocardium with about 10(6) copies per 10(6) cells. mRNA of capsid proteins was present in two bone marrow samples only. In conclusion, in asymptomatic individuals B19V persistence is more common in solid tissues than in bone marrow, and genotype 2 persists more frequently than genotype 1. The results suggest that the virus persists without replicating, at sub-immunogenic levels.  相似文献   

20.
Epstein-Barr virus (EBV), a ubiquitous human herpesvirus, normally causes an asymptomatic latent infection with very low levels of circulating virus in the peripheral blood of infected individuals. However, EBV does have pathogenic potential and has been linked to several diseases, including posttransplant lymphoproliferative disease (PTLD), which involves very high circulating viral loads. As a consequence of immunosuppression associated with transplantation, children in particular are at risk for PTLD. Even in the absence of symptoms of PTLD, very high viral loads are often observed in these patients. EBV-infected B cells in the circulations of 16 asymptomatic pediatric solid-organ transplant recipients from Children's Hospital of Pittsburgh were simultaneously characterized for their surface immunoglobulin (sIg) isotypes and EBV genome copy numbers. Patients were characterized as having high and low viral loads on the basis of their stable levels of circulating virus. Patients with high viral loads had both high- and low-copy-number cells. Cells with a high numbers of viral episomes (>20/cell) were predominantly Ig null, and cells with low numbers of episomes were predominantly sIgM positive. Patients with low viral loads carried the vast majority of their viral load in low-copy-number cells, which were predominantly IgM positive. The very rare high-copy-number cells detected in carriers with low viral loads were also predominantly Ig-null cells. This suggests that two distinct types of B-lineage cells contribute to the viral load in transplant recipients, with cells bearing high genome copy numbers having an aberrant Ig-null cellular phenotype.  相似文献   

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