HLA-DRw6 as a risk factor for active cytomegalovirus but not for herpes simplex virus infection after renal allograft transplantation

HLA-DQ3 is a probable risk factor for CMV infection in high-risk kidney transplant patients

BACKGROUND

Cytomegalovirus (CMV) infection in transplant patients with special risk factors remains a major hazard. CMV-seronegative recipients with seropositive donors have the highest risk of developing acute CMV disease. We suggest that the HLA-type may influence the occurrence and the severity of primary CMV infection of these recipients and the measurement of the special HLA-types may be useful in the prediction of acute infection.

METHODS

Since 1999 1213 cadaver kidney transplantations have been performed in our clinic. 163 of 1213 recipients were CMV-seronegative (13%) and 129 of them received the kidney from seropositive donors. All 129 patients received CMV infection prophylaxis. Of 129 CMV-seronegative patients 49 developed acute CMV infection (38%) during the first posttransplant year. CMV infection was diagnosed by CMV antigenemia test and serologic measurements (ELISA). The particular HLA-genotypes of the recipients were studied before the transplantation. The occurrence and the severity of CMV infection was investigated in association with HLA-types.

RESULTS

We found different acute CMV infection distribution in the careers and non-careers of investigated HLA-types: HLA-A2, HLA-B12, HLA-Cw7, HLA-DR6 and HLA-DR11, but the differences were not significant in these HLA-types (P = 0.26, P = 0.37, P = 0.83, P = 0.07 and P = 0.37). While investigating HLA-DQ3, we found that of 68 DQ3-positive patients 32 (47%), of 61 DQ3-negative patients 17 (28%) had acute CMV infection and this difference was found to be significant. This result was confirmed by univariate and multivariate Cox Regression (P = 0.001) and the appropriate significance level was considered by Bonferroni correction.

CONCLUSIONS

HLA-DQ3 was found to be an independent predictor of CMV infection. Our data suggest that patients positive for HLA-DQ3 are more susceptible to CMV infection than a comparable group of patients negative for HLA-DQ3. This result was not due to rejection and/or treatment for rejection and was not influenced by induction therapy. Although we found more symptomatic infections among DQ3+ patients the difference was not significant (P = 0.19). Comparing the gender proportion among all 1213 kidney recipients and among CMV-seronegative recipients we found that the proportion of males is significantly higher among CMV-seronegative recipients (P < 0.001).

Cytomegalovirus disease after prophylaxis with oral ganciclovir in renal transplantation: the importance of HLA-DR matching

This study assessed the incidence of cytomegalovirus (CMV) disease and associated outcomes after oral ganciclovir prophylaxis in renal transplantation. A retrospective analysis was performed of all adult renal transplant recipients at a single transplant center transplanted between August 16, 1996, and December 31, 2000. CMV disease prophylaxis included ganciclovir 1000 mg orally thrice daily prescribed for 90 d in D-/R+ cases and 180 d in D+/R- and D+/R+ cases. Forty (9.1%) of 470 patients studied were diagnosed with CMV disease, which varied significantly by CMV serostatus and number of HLA-DR matches. The highest incidence of disease, 26.2%, was in D+/R- patients with zero HLA-DR matches. Five-year graft survival was 56.8% with CMV disease compared with 79.1% without (P < 0.001). Five-year graft survival with CMV disease was 75.9% with one or two HLA-DR matches versus 16.2% with zero HLA-DR matches (P < 0.001). CMV remains an important factor in long-term graft survival after oral ganciclovir prophylaxis. However, we have observed that the adverse impact of CMV disease on graft survival is apparent only in patients with zero HLA-DR matches. These results call for the development of new CMV disease prophylaxis and treatment strategies in patients with zero HLA-DR matches. In addition, organ allocation policies discouraging combining CMV-seropositive donors and zero HLA-DR matches may be worth consideration.

Cytomegalovirus and HLA-A, B, and DR locus interactions: impact on renal transplant graft survival

Graft failure rates for renal transplantations performed between 1989 and 1994 and recorded in the US Renal Data System database were retrospectively evaluated for interactions between cytomegalovirus and HLA-A, B, and DR loci. Twelve significant interactions were observed. There were significantly greater risks of graft failure for the total effect of cytomegalovirus and donor or matched HLA-DR9, recipient or matched HLA-B-51, and matched HLA-B13. We conclude that further study of renal transplants with these combinations of cytomegalovirus and HLA loci is needed to determine whether the observed interactions should be taken into consideration when matching donors with recipients.

Risk factors for cytomegalovirus infection and disease in renal transplant recipients: HLA-DR7 and triple therapy

In a prospective study, an analysis of risk factors for the development of cytomegalovirus (CMV) infection and disease was performed on 77 renal allograft recipients. Twenty-five out of the 77 recipients (32%) had a CMV infection. Twenty-two of the recipients received triple immunosuppressive therapy (cyclosporin A, prednisolone, and azathioprine) while the remaining 55 received standard therapy (cyclosporin A and prednisolone). In 23 recipients (30%) acute rejection was diagnosed and the first positive parameter of infection occurred 22 days after rejection therapy. Infection occurred in 10 out of 18 HLA-DR7-positive recipients (56%) and in 15 out of 59 HLA-DR7-negative recipients (25%; P < 0.02). In multiple regression analysis, HLA-DR7 was found to be a significant predictor of CMV infection (P < 0.005). CMV disease was diagnosed in only 9 out of 25 recipients with an acute infection. Six recipients (67%) with CMV disease received triple therapy for maintenance immunosuppression; this was significantly correlated to CMV disease (P < 0.05) as compared to three recipients (33%) with CMV disease maintained with standard therapy. Our data suggest that HLA-DR7-positive recipients are more susceptible to CMV infection and that CMV disease is associated with triple immunosuppressive therapy.

Factors influencing the occurrence of active cytomegalovirus (CMV) infections after organ transplantation

In this study, several factors influencing the occurrence of active CMV infection after organ transplantation (Tx) are analysed. For this purpose, 105 heart, kidney and lung transplant recipients who were CMV-positive or had a CMV-positive donor, were closely monitored for active CMV infection by antigenaemia, cultures, CMV serology and lymphocyte proliferation (LP) to CMV. Univariate and multivariate regression analysis were performed. As pretransplant risk factors the HLA-type and numbers of HLA mismatches between recipients and their donors, and the CMV serology of the recipient and donor were analysed. A new finding was that recipients of donors positive for HLA-B7 were especially at risk for developing active CMV infection (P = 0.03) and CMV disease (P = 0.03). This was not due to increased rejection treatment in these patients. Post-transplant risk factors for development of active CMV infection were absence of detectable cellular immunity to CMV (lymphocyte proliferation) after Tx (P < 0.01) and rejection treatment with OKT3 or ATG (P = 0.05). High levels of IgG anti-CMV did not prevent occurrence of active CMV infection or CMV disease in the CMV+ recipients.

Opportunistic infections in children following renal transplantation

Opportunistic infections following renal transplantation in children are a major cause of severe morbidity and mortality. These infections account for the majority of early post renal-transplant deaths in children. General risk factors which affect the incidence and severity of these infections include: transmission of the infectious agent by the donor organ; history of immunity in the recipient prior to transplantation; type and amount of immunosuppression including treatment for rejection episodes; availability of specific treatment for the infection. Children are at particular risk because of the lack of exposure to certain pathogens prior to transplantation. There have been recent advances in the prevention and treatment of important infections which occur in children following transplantation, including varicella, Pneumocystis carinii pneumonia (PCP) and cytomegalovirus (CMV) disease. Varicella is treatable with acyclovir, often without decreasing immunosuppression and placing the graft at risk. Prophylaxis against PCP may be achieved by provision of alternate-day trimethoprim sulpha, but clear guidelines for determining who should be treated are lacking. Treatment of this disease with high-dose trimethoprim sulfa or pentamidine is usually successful. CMV disease is frequently severe, especially when the donor is seropositive and the recipient seronegative. In these situations, prophylactic CMV immunoglobulin reduces the morbidity and the mortality of the disease and prophylactic oral acyclovir may decrease its incidence. Treatment of severe CMV disease with gancyclovir is promising.

Simultaneous primary infection with HIV and CMV leading to severe pancytopenia, hepatitis, nephritis, perimyocarditis, myositis, and alopecia totalis

Simultaneous primary infection with HIV and CMV in an 18-year-old woman led to an acute cytotoxic reaction, manifesting as pancytopenia, hepatitis, nephritis, perimyocarditis, and myositis. Within 14 days parameters indicating acute cell damage reverted to normal. Two weeks later transient alopecia totalis developed. Initially, HIV-antigen but no HIV antibodies were present. Within 3 weeks HIV-IgG antibodies appeared while HIV antigen disappeared. Anti-CMV-IgM was clearly and anti-CMV-IgG questionably positive; IgM persisted further, while IgG remained definitely undetectable. We speculate that a particular HIV-induced imbalance of the immune system led to a generalized severe cytotoxic reaction to a simultaneous infection with CMV.

Cytomegalovirus infection after organ transplantation: an update with special emphasis on renal transplantation

Cytomegalovirus infections are still the most important infectious complications after organ transplantation. Besides historical notes this review will deal with new aspects concerning the epidemiology of the CMV, diagnostic modalities of CMV infection, the delicate counterbalance between the immune system and the CMV, as well as the symptomatology of this infection. Furthermore, aspects like prophylaxis and new, promising therapeutic regimes for treatment of infection will be dealt with. Although this update is applicable for all types of solid organ transplantation, emphasis will be on renal transplantation.

A review of mechanism of action of aspirin and its potential as an immunomodulating agent

The basic aspects of PG immune function interactions are presented and discussed herein. Specifically, the findings of many of the studies summarized suggest the possibility that pharmacologic actions of aspirin may play a role in enhancing the immune response to viral infections. Mechanisms proposed for ASA include: PG inhibition via the cyclooxygenase pathway, an interaction with cyclic nucleotides, altered cellular interactions with PG's, altered leukocyte migration, activation of complement components, stimulation of monocytopoiesis, and induction of interferon. Since dual effects for ASA have been observed for several of these mechanisms, it is clear that its role in modulating the immune response to viral infections is very complex. This delineation of a role for ASA, that would seem to constitute a defense against viral infections leads to an area worthy of study and surveillance.

Immunity to cytomegalovirus in women with unexplained recurrent spontaneous abortion

Humoral and cellular immunity to cytomegalovirus (CMV) has been assessed in women suffering unexplained recurrent spontaneous abortions (RSA). A significantly lower prevalence of serum anti-CMV antibodies was observed for RSA women compared with either their male partners or age-matched female controls, unlike for serum antibodies to Herpes simplex virus. In addition, there was a markedly impaired lymphocyte proliferative response to CMV for CMV-sero-positive RSA women compared with CMV-seropositive controls. These results indicate that women with unexplained RSA have difficulty in responding to CMV, and are of significance when considering leukocyte transfusion immunotherapy.