Comparing cytomegalovirus prophylaxis in renal transplantation: single center experience

Effectiveness of Prophylactic Human Cytomegalovirus Hyperimmunoglobulin in Preventing Cytomegalovirus Infection following Transplantation: A Systematic Review and Meta-Analysis

Cytomegalovirus (CMV) is a common infection occurring in patients undergoing solid organ transplantation (SOT) or hematopoietic stem cell transplantation (HSCT). CMV-specific hyperimmunoglobulin (CMVIG) has been used for the past four decades and is typically administered either prophylactically or pre-emptively. The present meta-analysis evaluated CMV infection rates in SOT patients who received prophylactic CMVIG. PubMed and the Cochrane Library were searched for studies published up to October 2021. The primary endpoint was CMV infection rate. Thirty-two SOT studies were identified (n = 1521 CMVIG-treated and n = 1196 controls). Prophylactic CMVIG treatment was often associated with a lower risk of CMV infection in transplant recipients. The average CMV infection rate was 35.8% (95% confidence interval [CI]: 33.4−38.2%) in patients treated prophylactically with CMVIG and 41.4% (95% CI: 38.6−44.2%) in the control group not receiving CMVIG (p = 0.003). Similar results were observed in analyses limited to publications evaluating currently available CMVIG products (Cytotect CP and Cytogam; p < 0.001). In combination with the established safety profile for CMVIG, these results suggest that prophylactic CMVIG treatment in patients undergoing solid organ transplantation may be beneficial, particularly in those at high risk of CMV infection or disease.

Phase 2 Randomized, Double-Blind, Placebo-Controlled Trial of RG7667, a Combination Monoclonal Antibody, for Prevention of Cytomegalovirus Infection in High-Risk Kidney Transplant Recipients

Cytomegalovirus (CMV) infection is a significant complication after kidney transplantation. We examined the ability of RG7667, a combination of two monoclonal antibodies, to prevent CMV infection in high-risk kidney transplant recipients in a randomized, double-blind, placebo-controlled trial. CMV-seronegative recipients of a kidney transplant from a CMV-seropositive donor (D+R-) were randomized to receive RG7667 (n = 60) or placebo (n = 60) at the time of transplant and 1, 4, and 8 weeks posttransplant. Patients were monitored for CMV viremia every 1 to 2 weeks posttransplant for 24 weeks. Patients who had seroconverted (D+R+) or withdrawn before dosing were excluded from the analysis (n = 4). CMV viremia occurred in 27 of 59 (45.8%) patients receiving RG7667 and 35 of 57 (61.4%) patients receiving placebo (stratum-adjusted difference, 15.3%; P = 0.100) within 12 weeks posttransplant and in 30 of 59 (50.8%) patients receiving RG7667 and 40 of 57 (70.2%) patients receiving placebo (stratum-adjusted difference, 19.3%; P = 0.040) within 24 weeks posttransplant. Median time to CMV viremia was 139 days in patients receiving RG7667 compared to 46 days in patients receiving placebo (hazard ratio, 0.53; P = 0.009). CMV disease was less common in the RG7667 than placebo group (3.4% versus 15.8%; P = 0.030). Adverse events were generally balanced between treatment groups. In high-risk kidney transplant recipients, RG7667 was well tolerated, numerically reduced the incidence of CMV infection within 12 and 24 weeks posttransplant, delayed time to CMV viremia, and was associated with less CMV disease than the placebo. (This study has been registered at ClinicalTrials.gov under registration no. NCT01753167.).

Cytomegalovirus seroprevalence among solid organ donors in Hungary: correlations with age, gender, and blood group

BACKGROUND

Cytomegalovirus (CMV) is endemic throughout the world, affecting most of the population, but the seroprevalence of CMV is known to vary among countries. CMV causes a mild infection in persons with intact immunity; however, CMV infection in organ transplantation is associated with significant morbidity and mortality. The present retrospective study was designed to evaluate the age-, gender-, and blood group-adjusted CMV seroprevalence among solid organ donors, representing fairly the overall Hungarian population (according to Hungarian Central Statistic Institute). This information is important for calculating risk-factors for CMV-seronegative recipients. No nationwide estimates of CMV seroprevalence in Hungary (as a representative of Eastern Middle Europe) have been published yet.

METHODS

We investigated 2070 organ donors for CMV seroprevalence by measuring the CMV-specific immunoglobulin G. The donors were divided into 3 age groups (2-20, 21-50, and 51-70 years old). A study was also conducted on a fourth group consisting of 200 residents from an old age home. CMV seroprevalence differences were searched according to age-, gender- and blood-group distribution.

RESULTS

The CMV seroprevalence of organ donors is 85% and of all investigated persons is 86%. The age-specific prevalence increases, starting from 72% in the first group to 99% in the fourth group. Seroprevalence of females was found to be significantly higher than of males (P=.0001).

CONCLUSION

We have shown that the overall CMV seroprevalence in the Hungarian population is moderately high at 86%. The opportunity for CMV-seronegative recipients to get a graft from a seronegative donor is statistically only 2%. The seroprevalence of the youngest age group is 72% and so it can be concluded that the Hungarian population acquires the infection mainly in childhood or in the early adulthood. Female gender is a risk factor for CMV infection. This fact must be taken into consideration during the planning of patients' follow-up, prophylaxis, and therapy.

Cytomegalovirus infection after kidney transplantation, susceptibility to CMV-infection in association with HLA-genotype — Doctoral dissertation summary

Cytomegalovirus infection is a major infectious complication of transplant recipients, causing significant morbidity and mortality. It is possible to treat this infection effectively only if we know the direct and indirect effects of it, if we take the risk-factors into account, and use sensitive and reliable diagnostic methods for early establishment of diagnosis. In order to avoid severe CMV-infection, it is possible to administer prophylactic therapy. For prophylaxis planning it is important to know the CMV-seroprevalence of Hungarian population and its characteristics. Our results have shown that the seroprevalence of Hungarian population is high: 86%. The primary CMV-infection in Hungary occurs in childhood or in early adulthood, till age of 20 years the seroprevalence is 72%. CMV-seronegative recipients should be transplanted using organs of seronegative donors, however, the chance obtaining the graft from a CMV-seronegative donor was shown to be 2% only. Since such seromatching is rear, we have to know that the constellation of negative recipient and positive donor is the highest risk-factor for developing severe primary CMV-infection. While investigating data of 147 CMV-seronegative recipients from high-risk group it has been established that CMV-infection prophylaxis is essential for high risk patients in the early post-transplant period of 3 months, the administration of any of investigated prophylactic protocols is advantageous in comparing with prophylaxis free management of those patients (P=0.006). The study has also proven that monoprophylaxis with ganciclovir or valganciclovir is the most effective and cost-effective procedure as compared to other protocols (P=0.006). It is important to take into consideration that in prophylactic groups the “late-onset” CMV-infection occurred often (25.4%), and that there were no signs of seroconversion after the primary CMV-infection in 14% of the patients. For the first time it has been found and proven that the female sex is a risk factor for CMV-infection (P=0.0006). Genetic variability influences susceptibility to infectious diseases and HLA-molecules are critical for viral antigen uptaking, processing and presenting. Our data of 129 of high-risk patients suggest that recipients positive for HLA-DQ3 are more susceptible to CMV-infection than a comparable group of patients negative for this HLA-type. This result was not due to rejection and/or treatment for rejection and was not influenced by induction therapy or number of HLA-mismatches. The multivariate Cox Regression analysis has shown that HLA-DQ3 positivity is an independent predictor of primary CMV-infection in CMV-seronegative recipients with seropositive donor grafts (P=0.001). The cognition of HLA-DQ3 is useful in the prediction of acute CMV-infection in high-risk patients, and should influence the planning of the patients' management.

Pneumonitis in human cytomegalovirus infection

Human cytomegalovirus (HCMV) is a beta herpes virus with a double stranded DNA genome of 240kbp. The virus is prevalent and establishes a latent infection in most adults. HCMV is an opportunistic pathogen for patients with impaired cellular immunity. HCMV pneumonia is a common presentation of HCMV disease in immunocompromised patients. The incidence of HCMV pneumonitis can be as high as 90% in lung transplant recipients. This paper takes a fresh look at the challenging perspectives of molecular, immunologic, cellular, diagnostic, clinical, and therapeutic characteristics of HCMV infection as future targets for development of antiviral strategies.

Gastrointestinal cytomegalovirus infections in organ transplant patients

A cytomegalovirus (CMV) az immunszupprimált szervtranszplantált betegek egyik veszélyes fertőzése. A transzplantáltak 80-90%-ánál a fertőzés inaktív; a tünetekkel járó CMV-betegség gyakorisága 30-40%-os. Gastrointestinalis CMV-betegség a szervátültetettek mintegy 10%-ában fordul elő, a kórkép a tápcsatorna bármelyik szakaszát érintheti. A CMV-betegség leggyakrabban a nyálkahártya károsodásával, fekélyekkel, eróziókkal, vérzésekkel jár, oka lehet a tápcsatorna motilitási zavarának, ritkábban gastrointestinalis gyulladásos teriméknek, perforációknak. A diagnosztika alapja az endoszkópos vizsgálat biopsziás mintavétellel. A biopsziás minta szövettani vizsgálatakor keresni kell a CMV-fertőzésre jellemző cytomegaliás sejteket intranukleáris („bagolyszem”) és intracitoplazmatikus zárványokkal. A vírus kimutatására számos mikrobiológiai, immunhisztokémiai és molekuláris biológiai módszer létezik. Igazolt kórkép esetén a kezelés kettős: az elváltozásoknak, tüneteknek megfelelő gasztroenterológiai kezelés mellett meg kell kezdeni az antivirális terápiát általában intravénás ganciclovirrel és/vagy orális valganciclovirrel. Lényeges a betegség kialakulásának megelőzése is: a magas rizikójú betegcsoportban általános profilaxis javasolt per os valganciclovirrel, speciális esetekben hiperimmunglobulinnal; közepes kockázat esetén a mikrobiológiai surveillance eredménye alapján preemptív kezelés kezdhető.

Acute rejection episodes in pediatric renal transplant recipients with cytomegalovirus infection

CMV infection is the most important opportunistic virus infection after renal transplantation leading to increased patient mortality, graft loss, risk for acute rejection episodes and impaired renal function. The potential impact of prophylactic anti-viral therapy on long-term graft outcome is relevant. The aim of this study was to evaluate the incidence of CMV infection, its risk factors and long-term outcome in children after renal transplantation. 103 children (mean age 10.6 +/- 5.3, range 1.6-22.0 yr) were monitored weekly for pp65 for the first 6-8 wk after renal transplantation, followed by a monthly monitoring for the first year. CMV infection occurred in 23/103 children (21.1%) with 10 patients (9.7%) developing CMV disease characterized by positive pp65 in the presence of organ involvement. The CMV R-/D+ and R+/D+ serostatus was significantly associated with an increased risk of CMV infection (p < 0.0001 and p = 0.009). 14/28 R-/D+ patients developed CMV infection despite prophylactic treatment with CMV hyperimmune globulin. The incidence of acute rejection episodes after or during CMV infection was significantly increased (p = 0.003) and the D+ serostatus was significantly associated with acute rejection episodes within the first year after transplantation (p = 0.006). In summary the overall incidence of CMV infection in this single center experience is 21.1%. The D+ serostatus represents a serious risk factor for both CMV infection and acute rejection episodes. In future the potential impact of different modalities of prophylactic anti-viral therapy on the prevention of acute rejection should be considered.

Prevention of CMV disease in pediatric kidney transplant recipients: evaluation of pp67 NASBA-based pre-emptive ganciclovir therapy combined with CMV hyperimmune globulin prophylaxis in high-risk patients

A new prevention strategy for CMV infection was evaluated in our pediatric kidney transplant unit. This approach comprises a pre-emptive therapy, based upon the monitoring of CMV pp67 mRNA in whole blood by the qualitative NASBA, combined with prophylactic CMV-IG in high risk (R-/D+) children. Thirty-one kidney transplant children were followed for six months with serial measurements of CMV pp67 mRNA in the blood. The R-/D+ patients were given prophylactic CMV-IG for the first 16 wk after transplantation. I.v. ganciclovir was administered upon CMV detection by NASBA and was discontinued after two consecutive negative results. CMV infection, detected by NASBA, developed in 11 (35%) recipients: one (33%) of the R+/D- patients and 10 (72%) of the R-/D+ patients. CMV disease developed in 9.6% of the patients (3/31), exclusively in the R-/D+ group. These three patients presented concurrently with CMV viremia and disease. It is noteworthy that two of the three patients could not receive a complete course of CMV-IG, and one of the latter two subjects had been treated for acute rejection 15 days before CMV infection. Ganciclovir was given for the 11 cases of primary infection, and for three cases of relapsed CMV infection. pp67 NASBA-based pre-emptive ganciclovir therapy, combined with prophylactic CMV-IG in high-risk patients leads to a lower rate of CMV disease, as long as a complete course of CMV-IG has been administered and ganciclovir is given during the period of treatment for acute rejection in high-risk populations.

Cytomegalovirus infection after solid-organ transplantation, its risk factors, direct and indirect effects and prevention strategies

A humán populációban szélesen elterjedt cytomegalovírus által okozott infekció egyike a leggyakrabban előforduló szervátültetést követő virális eredetű fertőzéseknek, amely befolyásolja a transzplantált szerv és a beteg túlélését is. Leggyakrabban a súlyos tünetekkel járó fertőzés olyan transzplantáltaknál alakul ki, akik cytomegalovírus-szeronegatívak az átültetés idejében, és a szervet szeropozitív donortól kapják. A fertőzés előfordulását és súlyosságát egyéb rizikótényezők is befolyásolják: az immunszuppresszió intenzitása, a beültetett szerv típusa, a graftkilökődés és/vagy ennek kezelése, a donor és recipiens közötti „HLA-mismatch”, a recipiens egyes HLA-típusai, női nem stb. A már kialakult cytomegalovírus-infekciónak direkt (tünetek) és indirekt (szövetkárosító és immunmoduláló) hatásai vannak, mindkettő befolyásolja a beteg életminőségét és a további állapot alakulását. Ezért speciális kezelési sémákat és a megelőzésre irányuló intézkedéseket dolgoztak ki, amelyek segítségével a cytomegalovírus károsító hatása csökkenthető vagy elkerülhető. Számos preventív lehetőség közül a gyakorlatban két megelőzési stratégia alkalmazható hatékonyan: az univerzális profilaxis (részét képezi a szelektív profilaxis) és a preemptív terápia. A szerzők – saját és külföldi tapasztalatok alapján – összefoglalják a prevenciós lehetőségeket, összehasonlítják az alkalmazott protokollok előnyeit és hátrányait. Az Amerikai és Kanadai Transzplantációs Társaságok ajánlása alapján a legtöbb amerikai, de sok európai transzplantációs központban is a betegeket három csoportba sorolják: magas, közepes és alacsony rizikójú csoportok; a besorolásnak megfelelően választható a profilaxis. A magas rizikójú betegcsoportoknál (R–/D+ betegek és tüdőtranszplantáltak) nélkülözhetetlen az univerzális profilaxis. Azoknál a betegeknél, akik antilymphocyta-ellenanyagot (ATG, ALG vagy OKT3) kapnak, szükséges az ún. szelektív profilaxis alkalmazása. A közepes rizikójú betegcsoportoknál (R+/D+ vagy R+/D–) lehet választani az univerzális profilaxis és a preemptív terápia között a klinika adottságait figyelembe véve. A nagy forgalmú ambulanciákon, a szoros monitorozás nehézségei és a költséges laboratóriumi vizsgálatok miatt, továbbá a CMV-fertőzés indirekt hatásainak kiküszöbölése érdekében az ajánlások az univerzális profilaxis alkalmazását javasolják. Az alacsony rizikójú csoportban (R–/D–) vese-, máj-, hasnyálmirigy-, szívtranszplantáció esetén a megelőzés szükségességét a transzplantációs centrum dönti el.

Exploring the native human antibody repertoire to create antiviral therapeutics

Native human antibodies are defined as those that arise naturally as the result of the functioning of an intact human immune system. The utility of native antibodies for the treatment of human viral diseases has been established through experience with hyperimmune human globulins. Native antibodies, as a class, differ in some respects from those obtained by recombinant library methods (phage or transgenic mouse) and possess distinct properties that may make them ideal therapeutics for human viral diseases. Methods for cloning native human antibodies have been beset by technical problems, yet many antibodies specific for viral antigens have been cloned. In the present review, we discuss native human antibodies and ongoing improvements in cloning methods that should facilitate the creation of novel, potent antiviral therapeutics obtained from the native human antibody repertoire.

Association of the Outcome of Renal Transplantation with Antibody Response to Cytomegalovirus Strain--Specific Glycoprotein H Epitopes

BACKGROUND

Cytomegalovirus (CMV) is the most important pathogen affecting the outcome of renal transplantation. The combination of CMV-seronegative transplant recipients with CMV-seropositive transplant donors places recipients at the highest risk of CMV disease. In cases of congenital CMV infection, existing immunity only partially protected mothers from reinfection with a different genotypic strain. The effect of differences in infected CMV strains between CMV-seropositive transplant donors and CMV seropositive transplant recipients on the outcome of transplantation remains unclear.

METHODS

In this prospective multicenter study, the presence of antibodies against strain-specific glycoprotein H epitopes in 84 CMV-seropositive transplant donor/CMV-seropositive transplant recipient renal transplantation cases were determined, and their relationships to acute transplant rejection, CMV infection, degree of antigenemia, and CMV disease were evaluated.

RESULTS

Among the 84 donor/recipient pairs, 45 and 32 had matched and mismatched strain-specific glycoprotein H antibodies, respectively. Acute transplant rejection in the mismatched group was more frequent than it was in the matched group (63% vs. 22%; P=.005). CMV disease was also more frequently observed in the mismatched group (28% vs. 9%; P=.026). The mismatched group had a higher level of antigenemia (P=.019).

CONCLUSIONS

Our results illustrate more adverse events in the cases with a CMV-seropositive transplant donor and a CMV-seropositive transplant recipient in which the glycoprotein H antibodies are mismatched, suggesting that reinfection with a different CMV strain results in more complications.