Association between individual and combined SNPs in genes related to innate immunity and incidence of CMV infection in seropositive kidney transplant recipients.

In this study, we assessed the association between single-nucleotide polymorphisms (SNPs) in seven candidate genes involved in orchestrating the immune response against cytomegalovirus (CMV) and the 12-month incidence of CMV infection in 315 CMV-seropositive kidney transplant (KT) recipients. Patients were managed either by antiviral prophylaxis or preemptive therapy. CMV infection occurred in 140 patients (44.4%), including 13 episodes of disease. After adjusting for various clinical covariates, patients harboring T-allele genotypes of interleukin-28B (IL28B) (rs12979860) SNP had lower incidence of CMV infection (adjusted hazard ratio [aHR]: 0.66; 95% confidence interval [CI]: 0.46-0.96; p-value = 0.029). In the analysis restricted to patients not receiving prophylaxis, carriers of the TT genotype of toll-like receptor 9 (TLR9) (rs5743836) SNP had lower incidence of infection (aHR: 0.61; 95% CI: 0.38-0.96; p-value = 0.035), whereas the GG genotype of dendritic cell-specific ICAM 3-grabbing nonintegrin (DC-SIGN) (rs735240) SNP exerted the opposite effect (aHR: 1.86; 95% CI: 1.18-2.94; p-value = 0.008). An independent association was found between the number of unfavorable SNP genotypes carried by the patient and the incidence of CMV infection. In conclusion, specific SNPs in IL28B, TLR9 and DC-SIGN genes may play a role in modulating the susceptibility to CMV infection in CMV-seropositive KT recipients.

Use of mycophenolate sodium in stable renal transplant recipients in Spain: preliminary results of the MIDATA study.

INTRODUCTION: The use of mycophenolate mofetil (MMF) is limited by gastrointestinal adverse events (GI-AEs). Enteric-coated mycophenolate sodium (EC-MPS) was developed to avoid these effects. METHODS: This multicenter prospective study sought to analyze the clinical benefit of EC-MPS among 726 stable renal transplant recipients in Spain. The data collection included: doses and trough levels of mycophenolic acid (MPA) and calcineurin inhibitors (CNI), renal function, routine biochemical parameters (3-6 months preconversion, baseline, and 1, 3, 6, and 12 months of EC-MPS initiation), as well as graft and patient survivals and adverse events. RESULTS: The main indication for EC-MPS introduction was GI-AEs associated with MMF (44.1%). Preliminary data showed that before introduction of EC-MPs there was a progressive deterioration of renal function, as demonstrated by a negative slope of the creatinine clearance (P < .005). However, after EC-MPS conversion, the slope became positive (P < .05), suggesting an improvement in renal function. Only in 4.8%, EC-MPS was stopped due to GI-AEs. There was an increase in MPA serum levels (P < .01) and a reduction in CNI doses. Interestingly, 80% of 85 patients without MMF treatment because of severe GI-AEs tolerated EC-MPS, including 43% who could be treated with adequate doses of EC-MPS (>or=720 mg/d). CONCLUSIONS: There was a significant improvement in GI-AEs after conversion from MMF to EC-MPS. The use of lower doses of CNI and the better tolerability of EC-MPS could be the underlying causes of improvement in renal function.

Use of the new proliferation signal inhibitor everolimus in renal transplant patients in Spain: preliminary results of the EVERODATA registry.

Everolimus (Eve) has shown good efficacy and safety profiles in clinical trials in combination with low doses of cyclosporine but there is limited experience in other modes, especially with calcineurin inhibitor elimination. We developed a retrospective study to analyze its clinical use after approval in Europe in 2005. Herein we have presented the results of a series of 272 patients followed for the first 6 months after Eve introduction. In 93.8% of cases Eve was introduced after the first month posttransplantation (conversion use), and 6 months after introduction, the CNI had been eliminated in 75% of cases. The main indication for Eve introduction was the diagnosis of a malignant neoplasm (42%), whereas the combined indication of prevention and/or treatment of toxicity, especially nephrotoxicity, accounted for 46.3% of cases. Initial doses were low (1.37 mg/d), but were progressively increased up to 2 mg/d at 6 months. Renal function remained unchanged during the follow-up period, whereas proteinuria moderately increased. Only 5 cases (2%) of acute rejection episodes were observed with excellent patient and graft survivals at 6 months after conversion. Further analysis of this extensive series of patients with a longer follow-up is needed.

Renal donor implication in the origin of BK infection: analysis of genomic viral subtypes.

UNLABELLED: BK virus (BKV) reactivation in immunocompromised kidney transplant patients can produce a tubulointerstitial nephropathy (BKVN). Molecular tools that test for DNA-BKV provide early detection and assist in management, but some aspects of the pathogenesis of this infection, such as donor causality, remain unclear. MATERIALS AND METHODS: Between November 2004 and January 2006, 55 Spanish kidney donors were studied for BK infection. A quantitative PCR assay was performed on urine and serum to detect BKV. To determine the origin of the viral infection, a transcription control region of the BK polymorphism sequence was designed to identify the viral subtype. RESULTS: Fifteen of 55 (27%) donors were BK-PCR positive: 13 in urine and 2 in serum and urine. Moreover, monitoring of recipient pairs detected BK-PCR positivity in 14 of 73 recipients. We studied eight BK-PCR positive recipients (corresponding to four pairs) and their respective donors. The same viral genome was observed in the four pairs, namely, the A250-1-a, WW-like, AS, and JL genotypes. Interestingly, one of the four pairs showed the donor and the two recipients to display exactly the same JL genotype. CONCLUSION: On the basis of our preliminary results analyzing the molecular fingerprints of donor and recipient pairs, we have presented new data implicating the donor, in at least some cases, as the source of BK infection.

[Cytomegalovirus viral load and antigenemia in the monitorization of prophylactic treatment with valganciclovir in renal transplant recipients]. / Carga viral y antigenemia de citomegalovirus en la monitorización de la profilaxis con valganciclovir en pacientes con trasplante renal.

Cytomegalovirus (CMV) disease is one of the most relevant infectious complications in solid organ transplant, and we must perform an appropriate prophylactic intervention. The goal of this study was to evaluate the effectiveness of prophylactic treatment with valganciclovir in renal transplant recipients in the first three months post transplantation by shell vial urine culture assay, and by measuring antigenemia (pp65) and CMV viral load, the latter by PCR. The population of the study included 100 renal transplant recipients. We analyzed the results of 36 patients recruited between November 2003 and July 2004 who were receiving a prophylactic oral treatment with valganciclovir, and who had finished the follow-up period of 90 days. The three tests mentioned above were performed on days 7, 15, 30, 45, 60, 75 and 90. No positive antigenemia was detected, the virus was cultured in a urine specimen and, in one patient, three measurements of viral load in serum were positive. Preliminary results of the study suggest that universal chemoprophylaxis with valganciclovir is effective for the prevention of CMV infection in renal transplant recipients and that, although all three tests used were useful, the measurement of CMV viral load seems to be the most appropriate method for monitoring these patients.

Carga viral y antigenemia de citomegalovirus en la monitorización de la profilaxis con valganciclovir en pacientes con trasplante renal / Cytomegalovirus viral load and antigenemia in the monitorization of prophylactic treatment with valganciclovir in renal transplant recipients

La enfermedad por citomegalovirus (CMV) es una de las complicaciones infecciosas más importantes en el trasplante de órgano sólido, porlo que es necesario realizar una correcta profilaxis de ella. El objetivo del estudio es ver la eficacia de la profilaxis con valganciclovir en pacientesreceptores de riñón durante el primer trimestre postrasplante, mediante la determinación de antigenemia (pp65), cultivo en Shellvialde orina y carga viral cuantitativa por PCR del CMV. En el estudio se incluyen cien pacientes con trasplante renal. Se analizan los resultadosde 36 de ellos reclutados entre noviembre de 2003 y julio de 2004, que estaban recibiendo profilaxis con valganciclovir oral y habíancumplido los 90 días de seguimiento. Las tres pruebas mencionadas se hicieron los días 7, 15, 30, 45, 60, 75 y 90. No se detectó ningunaantigenemia positiva, en una muestra de orina se cultivó el virus y tres determinaciones de carga viral en suero fueron positivas, todas ellasdel mismo paciente. Con los resultados preliminares del estudio se puede apuntar que la quimioprofilaxis universal con valganciclovir resultaútil para la prevención de la infección por CMV en pacientes con trasplante renal y, aunque las tres técnicas descritas son válidas, la determinaciónde la carga viral del CMV parece ser la más adecuada para la monitorización de estos pacientes

Cytomegalovirus (CMV) disease is one of the most relevant infectious complications in solid organ transplant, and we must perform an appropriateprophylactic intervention. The goal of this study was to evaluate the effectiveness of prophylactic treatment with valganciclovir inrenal transplant recipients in the first three months post transplantation by shell vial urine culture assay, and by measuring antigenemia(pp65) and CMV viral load, the latter by PCR. The population of the study included 100 renal transplant recipients. We analyzed the resultsof 36 patients recruited between November 2003 and July 2004 who were receiving a prophylactic oral treatment with valganciclovir, andwho had finished the follow-up period of 90 days. The three tests mentioned above were performed on days 7, 15, 30, 45, 60, 75 and 90.No positive antigenemia was detected, the virus was cultured in a urine specimen and, in one patient, three measurements of viral load inserum were positive. Preliminary results of the study suggest that universal chemoprophylaxis with valganciclovir is effective for the preventionof CMV infection in renal transplant recipients and that, although all three tests used were useful, the measurement of CMV viral loadseems to be the most appropriate method for monitoring these patients

Comparison of quantitative PCR and antigenemia in cytomegalovirus infection in renal transplant recipients.

UNLABELLED: Cytomegalovirus infection is a common complication of renal transplantation. Antigen pp65 levels serve as indicators of viral load, although the technique is difficult to perform and interpret. We sought to determine whether quantitative PCR had a higher sensitivity and predictive value in CMV infection. METHODS: The study included 100 renal transplant recipients who were screened for IgM and IgG at the time of admission. On days 7, 15, 30, 45, 60, 75, 90, 120, 180, and 360, antigenemia tests were performed on blood (pp65) and urine, and a quantitative PCR on blood. Among 59 patients recruited between November 2003 and August 2004 the mean age was 54.5 +/- 12.9 years. Two patients did not reach 90 days follow-up (3%); four patients have not surpassed 90 days (7%); 22, 120 days (37%); and 31, 180 days (53%). Ninety-three percent of patients showed anti-IgG CMV-positive titers with all being IgM CMV-negative at baseline. The patients at risk for infection were given valgancyclovir as prophylaxis throughout the study. RESULTS: At 474 visits, 8 samples (2.4%) were positive with urine; 5 (1.4%) with pp65, and 15 (4.7%) with PCR. Among the 15 positive samples, two (>100,000 and 3250 copies) revealed agreement of positive IgM and shellvial test on urine; two (15,100 and 5670 copies), antigen pp65 1+; one (17,400 copies) with pp65 2+ and shellvial urine; two (99,400 and 28,300 copies) with pp65 1+ and shellvial urine; and eight remaining determinations, 749, 2250, 686, 928, 2250, 26600, 777, and 2790 copies. The rest of the tests were negative. CONCLUSION: The preliminary results of this study demonstrated that quantitative PCR was a useful rapid tool for diagnosing and monitoring CMV infections.

Polymerase chain reaction detection of BK virus and monitoring of BK nephropathy in renal transplant recipients at the University Hospital La Fe.

INTRODUCTION: Reactivation of BK infection occurs in immunocompromised hosts causing tubulointerstitial nephropathy (BKVN). Approximately 5% of kidney transplant recipients (KTR) develop BKVN, special half of whom lose their grafts. However, BKVN morphologic diagnosis on a renal biopsy is complicated, because the cytopathic changes can sometimes mimic rejection. Thus, BKV DNA-polymerase chain reaction (PCR) assay on serum, urine, and renal tissue is useful for early detection and monitoring of BKV. MATERIALS AND METHODS: We performed routine monthly urine cytologies looking for decoy cells as a marker of virus replication. Then, we performed a qualitative PCR on urine and serum in all recipients (independently of positive or negative cytology). We amplified 3 BK viral genome regions, LT (early transcription region) and VP1 (late transcription region) seeking a more accurate virus detection, and the TCR (control transcription region) region to perform a polymorphism sequence analysis to identify the BK genomic variant. Finally, the BKVN diagnosis was confirmed using renal biopsy. RESULTS: At present, 132 patients have been monitored. Thirteen of 40 (33%) were PCR-urine-positive cases (5 LT+/VP1- and 8 LT+/VP1+), and 10 of 132 (7.5%) were PCR-serum-positive cases (7 LT+/VP1- and 3 LT+/VP1+). When we compared PCR-urine and cytology results, 11 of 40 (27.5%) patients showed a positive cytology, 6 of whom were PCR- urine-positive (1 LT+/VP1- and 5 LT+/VP1+); whereas, 29 patients showed a negative cytology, 7 of whom were PCR-urine-positive(3 LT+/VP1- and 4 LT+/VP1+). Thus, comparison of PCR- urine and cytology results revealed false-positive and false-negative cases. Finally, TCR sequence analysis was performed in 9 patients to identify the BK genomic variants. CONCLUSION: Testing for BKV DNA in urine and serum is a noninvasive early detection assay and monitoring tool.