Viral prophylaxis in organ transplant patients

Soluble intercellular adhesion molecule (ICAM)-1 detects invasive fungal infections in patients following liver transplantation

PURPOSE

Despite antifungal prophylaxis, liver transplanted patients are endangered by invasive fungal infections (IFI). Routinely used microbiological procedures are hallmarked by significant weaknesses, which may lead to a delay in antifungal treatment.

METHODS

Culture-based fungal findings, routinely used biomarkers of infection/inflammation (e.g., procalcitonin or C-reactive protein), as well as corresponding plasma concentrations of soluble Intercellular Adhesion Molecule (ICAM)-1 were analysed in 93 patients during a period of 28 days following liver transplantation (LTX).

RESULTS

Plasmatic sICAM-1 was significantly elevated in patients affected by an IFI within the first 28 days in comparison to fungally colonised or unobtrusive LTX patients. sICAM-1 might therefore be helpful for the identification of IFI patients after LTX (e.g., Receiver Operating Characteristic (ROC)-Area Under the Curve (AUC): 0.714 at 14d after LTX). The diagnostic performance of sICAM-1 was further improved by its combined use with different other IFI biomarkers (e.g., midregional proadrenomedullin).

CONCLUSION

The diagnostic deficiencies of routinely used microbiological procedures for IFI detection in patients after LTX may be reduced by plasmatic sICAM-1 measurements. Clinical Trial Notation. German Clinical Trials Register: DRKS00005480.

Latent cytomegalovirus infection does not influence long-term disease outcomes in inflammatory bowel disease, but is associated with later onset of disease

OBJECTIVES

Cytomegalovirus (CMV) infection is common in the general population. CMV infection negatively affects disease course in transplant recipients and HIV patients. Whereas primary CMV infections may occur sporadically in seronegative patients, all seropositive patients with inflammatory bowel syndrome (IBD) are at risk for CMV reactivation due to the inflammatory mucosal and use of immunosuppressive medication. It is unclear whether latent CMV infection, and risk of reactivations, influences long-term disease outcomes. In this study, we aim to explore whether CMV infection affects disease outcomes in IBD patients.

METHODS

We performed a cross-sectional cohort study with 1404 patients with IBD from a single center. Clinical characteristics and disease outcomes were prospectively collected. We scrutinized CMV serology test results and performed additional CMV serology testing if serum was available.

RESULTS

Out of 699 IBD patients with CMV serology, 303 (43.3%) were seropositive, comparable to the general Dutch population. CMV seropositivity was associated with older age, longer IBD disease duration, non-Western origin, birth outside the Netherlands and a lower educational level (p-values ≤ .004). CMV seropositivity was not associated with more complicated long-term disease outcomes of IBD (p-values > .05). Seropositive patients presented with symptoms and were diagnosed at an older age compared to seronegative patients (p-values < .01).

CONCLUSIONS

CMV seropositivity does not influence disease outcomes of IBD patients and seems to be associated with a delay in IBD onset. Guidelines regarding CMV screening in patients with IBD are currently based on a low level of evidence. These data support the recommendation that routine CMV serology measurement is not necessary in the clinical care of IBD.

Acyclovir in the Treatment of Herpes Viruses – A Review

Background:

Herpes Simplex (HSV) viruses are widely spread, highly contagious human pathogens. The statistics indicate that 50-90% of adults worldwide are seropositive for these viruses, mainly HSV-1 and HSV-2. The primary infection results in the appearance of watery blisters (cold sores) on the skin, lips, tongue, buccal mucosa or genitals. The ocular infection is the major cause of corneal blindness in the Western World. Once the HSV virus enters human body, it cannot be completely eradicated because HSV viruses are able to change into their latent form which can survive the treatment. The viron resides in trigeminal ganglia of the host, who becomes vulnerable to the reoccurrence of the disease during the whole lifespan. The neurotropic and neuro-invasive properties of HSV are responsible for neurodegenerative illnesses, such as Alzheimer's disease. Acyclovir and its analogues, being the inhibitors of the viral DNA replication, are the only approved medicines for HSV infection therapies.

Objective:

The current paper presents the up-to-date overview of the important pharmacological features of acyclovir, its analogues and their delivery systems including the mechanism of action, routes of administration, absorption and metabolism, as well as side effects of the therapy.

Conclusion:

Acyclovir remains the gold standard in the treatment of herpes virus infections, mainly due to the emerging of the new delivery systems improving considerably its bioavailability. The analogues of acyclovir, especially their esters, characterized by significantly higher bioavailability and safety, may gradually replace acyclovir in selected applications.

Varicella-Zoster Virus-Induced Hepatitis in a Liver Transplant Recipient: A Case Report

Infections after solid organ transplantation are a major cause of mortality and morbidity. Varicella-zoster virus (VZV) infection after solid organ transplantation is rare. Here we present a case presenting with acute hepatitis and shingles after a liver transplantation (LT). A 36-year-old male patient underwent a liver transplantation; 7 months later his liver function tests increased. An examination and test results revealed that he had VZV-induced hepatitis. After VZV treatment, his test results returned to normal levels. Hepatic involvement of VZV infection is rare, but it may be fatal in immunocompromised individuals. Early diagnosis and early initiation of antiviral therapy is important in the control of hepatitis and rare hepatotropic viruses in immunocompromised individuals.

New approaches for the detection of invasive fungal diseases in patients following liver transplantation-results of an observational clinical pilot study

PURPOSE

Despite antifungal prophylaxis following liver transplantation (LTX), patients are at risk for the development of subsequent opportunistic infections, such as an invasive fungal disease (IFD). However, culture-based diagnostic procedures are associated with relevant weaknesses.

METHODS

Culture and next-generation sequencing (NGS)-based fungal findings as well as corresponding plasma levels of ß-D-glucan (BDG), galactomannan (GM), interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), interleukin (IL)-2, -4, -6, -10, -17A and mid-regional proadrenomedullin (MR-proADM) were evaluated in 93 patients at 6 consecutive time points within 28 days following LTX.

RESULTS

A NGS-based diagnostic approach was shown to be suitable for the early identification of fungal pathogens in patients following LTX. Moreover, MR-proADM and IL-17A in plasma proved suitable for the identification of patients with an IFD.

CONCLUSION

Plasma measurements of MR-proADM and IL-17A as well as a NGS-based diagnostic approach were shown to be attractive methodologies to attenuate the weaknesses of routinely used culture-based diagnostic procedures for the determination of an IFD in patients following LTX. However, an additional confirmation within a larger multicenter trial needs to be recommended.

TRIAL REGISTRATION

German Clinical Trials Register: DRKS00005480 .

Herpes zoster in kidney transplant recipients: protective effect of anti-cytomegalovirus prophylaxis and natural killer cell count. A single-center cohort study

Despite its impact on quality of life and potential for complications, specific risk and protective factors for herpes zoster (HZ) after kidney transplantation (KT) remain to be clarified. We included 444 patients undergoing KT between November 2008 and March 2013. Peripheral blood lymphocyte subpopulations were measured at baseline and months 1 and 6. The risk factors for early (first post-transplant year) and late HZ (years 1-5) were separately assessed. We observed 35 episodes of post-transplant HZ after a median follow-up of 48.3 months (incidence rate: 0.057 per 1000 transplant-days). Median interval from transplantation was 18.3 months. Six patients (17.1%) developed disseminated infection. Postherpetic neuralgia occurred in 10 cases (28.6%). The receipt of anti-cytomegalovirus (CMV) prophylaxis with (val)ganciclovir decreased the risk of early HZ [adjusted hazard ratio (aHR): 0.08; 95% CI: 0.01-1.13; P-value = 0.062], whereas the natural killer (NK) cell at month 6 was protective for the occurrence of late HZ [aHR (per 10-cells/μl increase): 0.94; 95% CI: 0.88-1.00; P-value = 0.054]. In conclusion, two easily ascertainable factors (whether the patient is receiving anti-CMV prophylaxis and the NK cell count at month 6) might be potentially useful to tailor preventive strategies according to individual susceptibility to post-transplant HZ.

Preventive Strategies Against Cytomegalovirus and Incidence of α-Herpesvirus Infections in Solid Organ Transplant Recipients: A Nationwide Cohort Study

We assessed the impact of antiviral preventive strategies on the incidence of herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections in a nationwide cohort of transplant recipients. Risk factors for the development of HSV or VZV infection were assessed by Cox proportional hazards regression. We included 2781 patients (56% kidney, 20% liver, 10% lung, 7.3% heart, 6.7% others). Overall, 1264 (45%) patients received antiviral prophylaxis (ganciclovir or valganciclovir, n = 1145; acyclovir or valacyclovir, n = 138). Incidence of HSV and VZV infections was 28.9 and 12.1 cases, respectively, per 1000 person-years. Incidence of HSV and VZV infections at 1 year after transplant was 4.6% (95% confidence interval [CI] 3.5-5.8) in patients receiving antiviral prophylaxis versus 12.3% (95% CI 10.7-14) in patients without prophylaxis; this was observed particularly for HSV infections (3% [95% CI 2.2-4] versus 9.8% [95% CI 8.4-11.4], respectively). A lower rate of HSV and VZV infections was also seen in donor or recipient cytomegalovirus-positive patients receiving ganciclovir or valganciclovir prophylaxis compared with a preemptive approach. Female sex (hazard ratio [HR] 1.663, p = 0.001), HSV seropositivity (HR 5.198, p < 0.001), previous episodes of rejection (HR 1.95, p = 0.004), and use of a preemptive approach (HR 2.841, p = 0.017) were significantly associated with a higher risk of HSV infection. Although HSV and VZV infections were common after transplantation, antiviral prophylaxis significantly reduced symptomatic HSV infections.

Impact of Desensitization on Antiviral Immunity in HLA-Sensitized Kidney Transplant Recipients

Viral infections represent significant morbidity and mortality factors in kidney transplant recipients, with CMV, EBV, and BKV infections being most common. Desensitization (DES) with IVIg and rituximab with/without plasma exchange followed by kidney transplantation with alemtuzumab induction increased successful transplant rates in HLA-sensitized patients but may represent an increased risk for viral infections due to severe lymphocyte depletion. Here, we report on the posttransplant viral infection status in 372 DES versus 538 non-DES patients. CMV and EBV viremia were significantly lower in DES patients, while BKV viremia was similar. This trend was observed primarily in CMV sero(-), EBV sero(+), and sero(-) patients. No patient developed PTLD. The incidence of BKAN, allograft, and patient survival was similar in both groups. These viral infections were not associated with subsequent allograft rejection which occurred within 6 months after the infection. Conclusions. The IVIg + rituximab desensitization combined with alemtuzumab induction with triple immunosuppression maintenance does not increase the risk for CMV, EBV, and BKV infections. Possible factors include, in addition to posttransplant antiviral prophylaxis and PCR monitoring, presence of memory T cells and antibodies specific to CMV and likely EBV, NK cell-mediated ADCC despite lymphocyte depletion, elimination of EBV and CMV reservoirs by rituximab and alemtuzumab, and use of IVIg with antiviral properties.

Single Nucleotide Polymorphisms and Long-Term Clinical Outcome in Renal Transplant Patients: A Validation Study

Genome-wide association studies (GWAS) are designed to investigate single nucleotide polymorphisms (SNPs) and the association with a clinical phenotype. A previous GWAS performed in 300 renal transplant recipients identified two SNPs (rs3811321 and rs6565887) associated with serum creatinine and clinical outcome. We sought to validate these findings. Genotyping of the two SNPs was performed using Taqman assays in 1638 Caucasians participating in the Assessment of LEscol in Renal Transplant (ALERT) study. Primary endpoint was death-censored graft loss, and secondary endpoint was all-cause mortality. Applying Cox regression, no crude association to graft loss was found for rs3811321 on chromosome 14 (hazard ratio [HR] 0.87, 95% CI 0.59-1.29, p = 0.50) or rs6565887 on chromosome 18 (HR 0.88, CI 0.62-1.25, p = 0.48). Multivariable adjustments did not change results, nor did evaluation of the number of risk alleles formed by the two SNPs. No association with mortality was detected. In conclusion, an impact of two SNPs on chromosomes 14 and 18 on death-censored graft survival or all-cause mortality was not confirmed. Our results emphasize the importance of validating findings from high-throughput genetics studies and call for large collaborative research initiatives in the field of transplantation outcomes.

Risk of infectious diseases and cutaneous tumours in solid organ recipients: A meta-analysis of literature

AIM: To compare the risk of cutaneous infections and tumours in kidney transplant recipients with data recently published about this topic.

METHODS: In the present work, we evaluated the incidence of bacterial, fungal and viral cutaneous infectious diseases and the development of skin cancers in a cohort of 436 patients who underwent a renal transplantation. The median age at transplantation of our patients was 50 years and the median duration of the immunosuppression was of 7.2 years. Data obtained from our cohort were compared with those obtained by a systematic review of the literature of the last 20 years about the same topic.

RESULTS: Infectious diseases were the most frequent dermatological disorders that were diagnosed after transplantation, affecting about the 16.5% of patients. Herpes virus reactivation occurs in about the 35% of patients and is more common within 6 mo from transplantation, whereas when the immunosuppression is reduced, skin infections are mainly represented by Human Papilloma Virus infections and localized mycosis, such as pityriasis versicolor and superficial candidiasis. Bacterial infections were relatively rare and occur mainly in the first months after transplantation. The cumulative risk to develop skin cancer enhance significantly over the time, as consequence of long-term immunosuppressive regiments. Endogenous and exogenous risk factors, as well as the schedule of immunosuppression can play a role and justify the different incidence of skin cancer in the various series.

CONCLUSION: Skin infections and cancer, commonly diagnosed in transplanted patients, impact on survival and life-quality, justifying the realization of follow-up programs for the early diagnosis and treatment.

Fatal cytomegalovirus disease after combination therapy with corticosteroids and rituximab for granulomatosis with polyangiitis

The association of cytomegalovirus (CMV) with autoimmune disease is poorly understood with suggested causality and reported viral reactivation coinciding with active inflammation. We report a case of a patient who presented with diffuse alveolar hemorrhage and acute renal failure from rapidly progressive glomerulonephritis ultimately diagnosed with granulomatosis with polyangiitis (GPA). She was acutely managed with plasmapheresis to reduce antibody-mediated end-organ damage, hemodialysis for worsening hyperkalemia and acidosis, and high-dose intravenous methylprednisolone. She was transitioned to oral prednisone and started on weekly rituximab with resultant remission induction over a three-week period at which point she developed reactivation of CMV causing severe fatal lung disease and viremia. The case highlights the multiple factors associated with CMV reactivation in cases of severe systemic inflammatory states and the need for further research to help establish practice guidelines regarding antimicrobial prophylaxis in patients with autoimmune diseases on prolonged courses of corticosteroids and biologic agents.

Temporal response of the human virome to immunosuppression and antiviral therapy

There are few substantive methods to measure the health of the immune system, and the connection between immune strength and the viral component of the microbiome is poorly understood. Organ transplant recipients are treated with posttransplant therapies that combine immunosuppressive and antiviral drugs, offering a window into the effects of immune modulation on the virome. We used sequencing of cell-free DNA in plasma to investigate drug-virome interactions in a cohort of organ transplant recipients (656 samples, 96 patients) and find that antivirals and immunosuppressants strongly affect the structure of the virome in plasma. We observe marked virome compositional dynamics at the onset of the therapy and find that the total viral load increases with immunosuppression, whereas the bacterial component of the microbiome remains largely unaffected. The data provide insight into the relationship between the human virome, the state of the immune system, and the effects of pharmacological treatment and offer a potential application of the virome state to predict immunocompetence.

Strategies for the prevention of infection after solid organ transplantation

Infection is a frequent complication of organ transplantation and is associated with significant morbidity and mortality. Preventative antimicrobial strategies are a key component of the care received by transplant patients. This review summarizes the evidence supporting anti-infective prophylaxis in this setting. Specific recommendations for the prevention of bacterial, fungal, viral and parasitic infection after transplant are made, with a focus on recent developments in the field of transplant infectious diseases.

Vaccination of the immunocompromised child

The development of vaccination is a major achievement in modern medicine. However, children treated with immunosuppression may not at all, or only in part, receive routine immunization due to uncertainty of its risks and effect. There is a substantial lack of pediatric studies concerning the efficacy and safety of vaccination in this patient group. Experience from similar adult groups and children with HIV infection can be used as a model for other disease categories. With increasing knowledge of the immunologic basis of vaccination and how immunosuppressive drugs interfere with the immune system, improved vaccines could be tailored, and adequate, individualized guidelines issued.

Atypical Presentation of Herpes Zoster Duplex Bilateralis in a Renal Transplanted Patient

Viral infections in renal transplant patients are an important cause of morbidity and mortality. In most cases, the clinical presentation of herpes zoster allows the diagnosis to be made only by history and physical examination. However, patients who are immunosuppressed may have uncommon presentations, and require a high index of suspicion and additional diagnostic testing for proper management. We report a rare presentation of herpes zoster duplex bilateralis involving symmetrical dermatomes over the lower limbs occurring in a woman with a recent history of renal transplantation. The skin lesions were also atypical representing a diagnostic challenge. This infection should be part of differential diagnosis of cutaneous manifestations in organ transplant recipients.

Atypical presentation of exophytic herpes simplex virus type 2 with concurrent cytomegalovirus infection: a significant pitfall in diagnosis

We report 3 unusual cases of atypical exophytic cutaneous herpes simplex virus (HSV) type 2 with concurrent cytomegalovirus (CMV) infection in immunosuppressed patients and raise awareness to the significant clinical and pathologic challenges in establishing the correct diagnosis. In all the 3 cases, the lesions presented as fungating plaques and nodules with areas of superficial erosion. Initial clinical differential included genital warts, syphilis, versus cutaneous malignancy. All the 3 patients were referred to the dermatology clinic where a combination of cutaneous biopsies, viral cultures of the lesions, polymerase chain reaction, CMV antigenemia, and immunoperoxidase stains for CMV and HSV confirmed the diagnosis of HSV type 2 with concurrent CMV infection. All the 3 patients were treated with oral valganciclovir with significant improvement noted at the follow-up visit. In addition, we review the previously reported HSV/CMV cutaneous coinfection cases.

A prospective analysis of the incidence of and risk factors for opportunistic infections in patients with inflammatory bowel disease

BACKGROUND

Immunosuppressants lead to an increased risk of infection, but few prospective studies have assessed the incidence of opportunistic infections in inflammatory bowel disease (IBD) patients, a high proportion of whom are treated with immunosuppressants. The aim of this study was to assess the age distribution of Japanese IBD patients with opportunistic infections and the risk factors associated with these infections.

METHODS

A multicenter, prospective study of 570 IBD patients was conducted. The patients were followed for up to 12 months to identify any new infections. The incidence of opportunistic infections and the age distribution of patients with these infections were analyzed. We carried out a case-control study in which 2 non-infected IBD patients were selected as controls for each case (infected IBD patient); the effect of medications on the infection rate was also examined.

RESULTS

Fifty-two (9.1 %) of 570 IBD patients developed opportunistic infections. Herpes simplex virus and herpes zoster virus infections were observed in 29 and 16 patients, respectively. No cases of active tuberculosis were observed. The incidence of opportunistic infections in patients aged 50 years or over was significantly higher than that in the other age groups (p = 0.01). The use of steroids (p = 0.02), thiopurine (p < 0.01), and immunosuppressant combination therapy (p < 0.01) was associated with an increased rate of opportunistic infections. However, the use of infliximab was not associated with an increased rate of opportunistic infections (p = 0.62). Multivariate analysis indicated that the use of thiopurine was an independent risk factor for opportunistic infections (p < 0.01).

CONCLUSIONS

Age ≥50 years and the use of immunosuppressants are risk factors for opportunistic infections in patients with IBD. In our cohort, tuberculosis was not seen as a complication of immunosuppressant therapy.

Increased risk of pneumocystis jiroveci pneumonia among patients with inflammatory bowel disease

OBJECTIVES

Patients with inflammatory bowel disease (IBD) may be at increased risk for pneumocystis jiroveci pneumonia (PCP). Our aims were (1) to determine the incidence and relative risk of PCP in IBD and (2) to describe medication exposures in patients with IBD with PCP.

METHODS

We performed a retrospective cohort study and a case series using administrative data from IMS Health Inc, LifeLink Health Plan Claims Database. In the cohort, patients with IBD were matched to 4 individuals with no IBD claims. PCP risk was evaluated by incidence rate ratio and adjusted Cox proportional hazards modeling. The demographics and medication histories of the 38 cases of PCP in patients with IBD were extracted.

RESULTS

The cohort included 50,932 patients with Crohn's disease, 56,403 patients with ulcerative colitis, and 1269 patients with unspecified IBD; matched to 434,416 individuals without IBD. The crude incidence of PCP was higher in the IBD cohort (10.6/100,000) than in the non-IBD cohort (3.0/100,000). In the adjusted analyses, PCP risk was higher in the IBD versus non-IBD cohort (hazard ratio, 2.96; 95% confidence interval, 1.75-4.29), with the greatest risk in Crohn's disease compared with non-IBD (hazard ratio, 4.01; 95% confidence interval, 1.88-8.56). In the IBD case series of PCP cases (n = 38), the median age was 49 (interquartile range, 43-57). A total of 20 individuals (53%) were on corticosteroids alone or in combination with other immunosuppression.

CONCLUSIONS

Although the overall incidence of PCP is low, patients with IBD are at increased risk. Patients with IBD with PCP are predominantly on corticosteroids alone or in combination before PCP diagnosis.

Maribavir inhibits Epstein-Barr virus transcription through the EBV protein kinase

Maribavir (MBV) inhibits Epstein-Barr virus (EBV) replication and the enzymatic activity of the viral protein kinase BGLF4. MBV also inhibits expression of multiple EBV transcripts during EBV lytic infection. Here we demonstrate, with the use of a BGLF4 knockout virus, that effects of MBV on transcription take place primarily through inhibition of BGLF4. MBV inhibits viral genome copy numbers and infectivity to levels similar to and exceeding levels produced by BGLF4 knockout virus.

Viral infection in renal transplant recipients

Viruses are among the most common causes of opportunistic infection after transplantation. The risk for viral infection is a function of the specific virus encountered, the intensity of immune suppression used to prevent graft rejection, and other host factors governing susceptibility. Although cytomegalovirus is the most common opportunistic pathogen seen in transplant recipients, numerous other viruses have also affected outcomes. In some cases, preventive measures such as pretransplant screening, prophylactic antiviral therapy, or posttransplant viral monitoring may limit the impact of these infections. Recent advances in laboratory monitoring and antiviral therapy have improved outcomes. Studies of viral latency, reactivation, and the cellular effects of viral infection will provide clues for future strategies in prevention and treatment of viral infections. This paper will summarize the major viral infections seen following transplant and discuss strategies for prevention and management of these potential pathogens.

Stem cell therapy - Hype or hope? A review

While the regeneration of a lost tissue is known to mankind for several years, it is only in the recent past that research on regenerative medicine/dentistry has gained momentum and eluded the dramatic yet scientific advancements in the field of molecular biology. The growing understanding of biological concepts in the regeneration of oral/dental tissues coupled with experiments on stem cells is likely to result in a paradigm shift in the therapeutic armamentarium of dental and oral diseases culminating in an intense search for “biological solutions to biological problems.” Stem cells have been successfully isolated from variety of human tissues including orofacial tissues. Initial evidence from pioneering studies has documented the likely breakthrough that stem cells offer for various life-threatening diseases that have so far defeated modern medical care. The evidence gathered so far has propelled many elegant studies exploring the role of stem cells and their manifold dental applications. This review takes you on a sojourn of the origin of stem cells, their properties, characteristics, current research, and their potential applications. It also focuses on the various challenges and barriers that we have to surmount before translating laboratory results to successful clinical applications heralding the dawn of regenerative dentistry.

Bone marrow transplantation combined with mesenchymal stem cells induces immune tolerance without cytotoxic conditioning

BACKGROUND

Transplantation of allogeneic donor bone marrow (BM) into sufficiently conditioned recipients is an effective approach to induce immune tolerance as assessed by mixed chimerism. However, this approach is hampered by the lack of feasible protocols devoid of cytoreductive conditioning. We investigated whether mixed chimerism could be established by intra-bone marrow-bone marrow transplantation (IBM-BMT) combined with bone marrow-derived mesenchymal stem cells (BMSCs) treatment without additional cytoreductive conditioning.

MATERIALS AND METHODS

The recipient mice (C57BL/6) accepted BMSCs from donor mice (Balb/c) through daily tail vein injection for 4 d followed by IBM-BMT immediately. Full-thickness skin grafts from donor mice as well as from the third party mice (ICR) were transplanted to the dorsum of the recipient mice after the combined IBM-BMT with BMSCs treatment. The immune tolerance was assessed by the survival time of skin allografts. The establishment of mixed chimerism and cytokine expression profile in recipient peripheral blood were determined by flow cytometry and enzyme-linked immunosorbent assay, respectively.

RESULTS

IBM-BMT combined with BMSCs treatment led to stable mixed chimerism and donor-specific skin graft tolerance. The flow cytometry analysis revealed that recipient mice developed 20%-25% chimerism levels among the myeloid lineage. The skin allografts survived more than 1 y and the hair re-grew normally on the grafts. Cytokine profile showed that IBM-BMT combined with BMSCs treatment prolonged humoral tolerance in recipient chimeras.

CONCLUSIONS

Our results demonstrate that donor specific immune tolerance can be effectively induced by IBM-BMT combined with BMSCs treatment without any additional cytoreductive recipient treatment. This approach provides a promising allograft transplantation strategy when the donor bone marrow is available.

Aciclovir and varicella-zoster-immunoglobulin in solid-organ transplant recipients

Clear recommendations for the management of acute varicella-zoster virus (VZV) infections for cases of significant exposure and the use of prophylactic drugs after solid-organ transplantation are missing due to the lack of evidence by prospective studies. Heterogeneity in patient groups, patient numbers, age groups, immunosuppressive regimens, timing, and dosage of aciclovir and/or varicella-zoster immunoglobulin (VZIG), pre-transplant vaccination or VZV wild-type infection and inconsistency of data make comparability of different studies impossible. Although the benefit of aciclovir and/or VZIG is uncertain in immunosuppressed children, prospective controlled double-blind studies are not feasible for ethical considerations as fatal cases with disseminating varicella disease are well known in these patient groups despite the use of aciclovir and/or VZIG, whereas severe side-effects of these drugs are rare. However, a reporting bias is likely as mainly severe or fatal cases might have been predominantly published or cases of successfully used aciclovir and/or VZIG in mild cases or in cases of breakthrough infections after vaccination. As neither VZIG prophylaxis nor treatment with intravenous aciclovir offers complete protection against severe VZV infection to immunosuppressed pediatric solid-organ transplant recipients, high priority should be given to vaccination against VZV prior to transplantation, and, most importantly, in their close contact persons. Clinical observations suggest that only assessment of humoral immunity together with cellular immunity may allow predication about protection in exposed patients.

Cost-effective immunosuppressive options for solid organ transplantation: a guide to lower cost for the renal transplant recipient in the USA

Of the numerous risks associated with immunotherapy for the prevention of rejection, cost is perhaps the most universal. In the USA and some other countries, the costs of immunosuppression make transplantation unavailable for some medically viable transplant candidates, and for others who receive a transplant, the long-term costs are economically crippling. Minimization and tapering of immunosuppression, use of generics, manipulation of metabolism, infection surveillance instead of prophylaxis, and advantageous routes of administration are some strategies that can be employed to reduce immunotherapy expense. Using these strategies, we describe an immunosuppression regimen for kidney transplantation that might be only a third of the cost of current 'standard' regimens in the USA. Such a regimen might allow some patients who might not otherwise qualify economically to safely receive a kidney transplant. The purpose of creating an alternative, lower-cost immunotherapy regimen is to give patients a choice. Responsible stewardship of scarce donor organs is the primary, and clearly appropriate, limiting factor.

[Role of viral infections in immunosuppressed patients]

Ser receptor de un trasplante de órgano sólido, así como recibir tratamiento quimioterápico para una enfermedad hematólógica maligna, predispone claramente a padecer infecciones virales tanto comunes como oportunistas, de origen tanto comunitario como procedentes del donante de órganos y/o de una reactivación de un virus latente endógeno. Herpes virus y más especialmente citomegalovirus y virus de Epstein-Barr son los que con más frecuencia afectan a estos enfermos, así como los virus respiratorios. El tratamiento consiste en la combinación de reducir la inmunodepresión inducida junto con tratamiento antiviral. Se ha realizado una revisión de la literatura pormenorizada y actualizada de la epidemiología, la patogenia, las manifestaciones clínicas y la aproximación terapéutica de las infecciones virales en estos enfermos.

Role of viral infections in immunosuppressed patients

Being a solid organ and hematopoietic stem cell transplant recipient as well as receiving chemotherapy for a malignant hematological disease clearly predispose the subject to a variety of viral infections, both common and opportunistic diseases. The patient may have acquired these infections from the community as well as from the donor organ (donor-derived infections) and/or from reactivation of an endogenous latent virus. Herpes viruses and especially the cytomegalovirus and Epstein-Barr virus are among the most common of the opportunistic viral pathogens affecting these patients, in addition to respiratory viruses. Treatment consists in antiviral drug therapies combined with the reduction in the degree of the induced immunosuppression. A review of the literature has been performed in order to update the epidemiology, pathogenesis, clinical manifestations and therapeutic approach of the viral infections in these immunocompromised patients.

Effects of acute cytomegalovirus infection on rat islet allograft survival

Transplantation of pancreatic islets is a promising therapy for the treatment of type 1 diabetes mellitus. However, long-term islet graft survival rates are still unsatisfactory low. In this study we investigated the role of cytomegalovirus (CMV) in islet allograft failure. STZ-diabetic rats received an allogenic islet graft in combination with either an acute CMV infection or control infection. A third group received ganciclovir treatment in addition to the CMV infection. Graft function was assessed by measuring basal blood glucose levels. After sacrifice, the islet grafts were retrieved for analysis of infection and leukocyte infiltration. CMV-infected recipients demonstrated accelerated islet graft failure compared to noninfected controls. CMV infection of the graft was only observed prior to complete graft failure. Quantification of the leukocyte infiltration demonstrated increased CD8(+) T-cell and NK cell infiltration in the CMV-infected grafts compared to the controls. This suggests that CMV infection accelerates immune-mediated graft destruction. Antiviral ganciclovir treatment did not prevent accelerated graft failure, despite effectively decreasing the grade of infection. Our data confirm the recently published CITR data, which state that CMV is an independent risk factor for failure of islet grafts. Also, our data demonstrate that new approaches for preventing virus-induced islet allograft failure may be required.

Famciclovir: a focus on efficacy and safety

IMPORTANCE OF THE FIELD

Famciclovir is the prodrug of penciclovir, a guanosine analogue that inhibits viruses of the alpha sub-family of the Herpesviridae, as well as hepatitis B virus. It is indicated for management of mucocutaneous herpes simplex virus disease and acute herpes zoster, and has been investigated for management of hepatitis B virus infection.

AREAS COVERED IN THIS REVIEW

Data for this review were identified by searches of papers published in English on Medline and Scopus, spanning the years 1975 through 1 February 2010 with the key words: 'famciclovir', 'famvir', 'penciclovir', 'herpes', 'oral', 'genital', 'varicella', 'zoster' and 'virus' in association with 'safety', 'toxicity', 'tolerability', 'efficacy' and 'indications'. Relevant references were also obtained from articles acquired through the search strategy.

WHAT THE READER WILL GAIN

Readers are also provided with up-to-date information on the use of famciclovir for infections due to herpes simplex, varicella zoster and hepatitis B viruses. Clinical data pertaining to the safety and tolerability of famciclovir are also reviewed.

TAKE HOME MESSAGE

Famciclovir is a safe, convenient, and well-tolerated drug when used for its approved indications. The most common side effects indicated in the majority of studies were headache and nausea. Data for its use in childhood and pregnancy are limited.

Detection of herpes viruses in respiratory secretions of patients undergoing artificial ventilation

The significance of detection of herpes viruses in respiratory secretions of critically ill patients is controversial. The study aim was to determine the prevalence of herpes virus DNA in respiratory secretions in patients on artificial ventilation. Respiratory secretions taken thrice weekly from 174 patients in a tertiary center intensive therapy unit (ITU) were tested for herpes simplex virus (HSV) by nested PCR. Samples from 61 patients in ITU for 4 days or more were also tested for Epstein Barr Virus (EBV) and cytomegalovirus (CMV) using real-time PCR. HSV positivity increased with ITU stay with 18.6% admission samples positive, 32.5% day 2-5 samples, and 65.9% day 6-39 samples. Being HSV positive on admission did not influence mortality (9/27, 33.3% vs. 38/118, 32.2%) however, subsequently, mortality of those negative but becoming positive was higher than in those remaining negative (10/35, 29% vs. 5/24 21%). At least one sample was EBV positive in 61% and CMV positive in 19% of patients tested. Of 63 patients tested for all three viruses, 4 were positive for three viruses, 23 patients for two viruses, 24 for one virus and 12 were negative for all the above viruses. Detection of HSV, EBV and CMV is common in ITU patients. Becoming HSV positive while in ITU may increase mortality.

New developments in the management of cytomegalovirus infection after solid organ transplantation

Despite remarkable advances in the diagnostic and therapeutic modalities for its management, cytomegalovirus (CMV) remains one of the most important pathogens impacting on the outcome of transplantation. Not only does CMV directly cause morbidity and occasional mortality, it also influences many short-term and long-term indirect effects that collectively contribute to reduced allograft and patient survival. Prevention of CMV infection and disease is therefore key in ensuring the successful outcome of solid organ transplantation (SOT). In this regard, antiviral prophylaxis and pre-emptive therapy are similarly effective in preventing CMV disease after transplantation. However, current guidelines prefer antiviral prophylaxis over pre-emptive therapy in preventing CMV disease in high-risk SOT recipients, such as CMV-seronegative recipients of organs from CMV-seropositive donors (CMV D+/R-), and lung, intestinal and pancreas transplant recipients. Antiviral prophylaxis has the benefits of reducing not only the incidence of CMV disease, but also the indirect effects of CMV on allograft and patient survival. The major drawback of antiviral prophylaxis is delayed-onset CMV disease, which occurs in 15-38% of CMV D+/R- SOT recipients who received 3 months of prophylaxis. Allograft rejection, over-immunosuppression and lack of CMV-specific immunity are factors that predispose patients to delayed-onset CMV disease. A recent randomized trial in CMV D+/R- kidney recipients demonstrates a significant reduction in the incidence of CMV disease when valganciclovir prophylaxis is extended to 200 days (compared with the standard 100 days) after transplantation; however, the safety and cost of this prolonged approach has yet to be assessed. In some studies, delayed-onset CMV disease has been significantly associated with allograft loss and mortality. In the vast majority of patients, CMV disease responds to treatment with intravenous ganciclovir. Recently, oral valganciclovir was demonstrated to have an efficacy that is comparable to intravenous ganciclovir in treating mild to moderate cases of CMV disease in SOT recipients. Reduction in the degree of immunosuppression should complement antiviral treatment of CMV disease. Although it remains rare, ganciclovir-resistant CMV disease is increasingly seen in clinical practice, potentially fostered by the prolonged use of antivirals in high-risk over-immunosuppressed transplant recipients. Treatment of drug-resistant CMV is currently non-standardized and may include foscarnet, cidofovir, CMV hyperimmune globulins or leflunomide. The investigational drug marivabir had the potential to treat ganciclovir-resistant CMV disease as it acts through a different mechanism. However, the recent phase III clinical trial in allogeneic bone marrow transplant recipients showed that maribavir was not significantly better than placebo for the prevention of CMV disease. Similarly, the preliminary data in a liver transplant population suggests that maribavir was inferior to oral ganciclovir for the prevention of CMV disease. This article reviews the recent data and other developments in the management of CMV infection after SOT.

Is screening for IgG antibody to cytomegalovirus and Epstein-Barr virus infections mandatory in potential renal transplant recipients and donors in Iran?

OBJECTIVE

Cytomegalovirus (CMV) and/or Epstein-Barr virus (EBV) infections in renal transplant recipients may cause significant morbidity and mortality. To manage these infections, established guidelines suggest that both the recipient and the donor be routinely tested for anti-CMV and anti-EBV antibodies prior to renal transplantation. The aim of this study was to assess the value of screening among people living in Iran.

PATIENTS AND METHODS

We retrospectively analyzed the incidences of CMV and EBV infections among 925 and 710 potential renal allograft donors and recipients, respectively, between 2005 and 2008. All cases were first transplantations. Enzyme-linked immunosorbent assays (ELISA) were performed to determine whether there were antibodies to CMV (IgG) or EBV viral capsid antigen (VCAIgG). Finally, we analyzed the seroprevalence and demographic factors.

RESULTS

Five hundred sixty-eight (61.40%) potential renal transplant donors and 483 (68.02%) potential renal transplant recipients were men. Donor ages ranged from 18 to 50 years (mean +/- SD, 34.7 +/- 8.1 years) and recipient ages ranged from 18 to 60 years (mean +/- SD, 45.9 +/- 7.3 years). Pretransplant CMV (IgG) and EBV (VCAIgG) seroprevalence was 100% among all donor, and recipient ages and sexes.

CONCLUSION

Our findings suggested that kidney transplant centers in Iran do not need to perform routine screening for IgG antibodies to CMV and EBV among renal transplant recipients and donors of ages >or=18 years.

Maribavir inhibits epstein-barr virus transcription in addition to viral DNA replication

Although many drugs inhibit the replication of Epstein-Barr virus (EBV) in cell culture systems, there is still no drug that is effective and approved for use in primary EBV infection. More recently, maribavir (MBV), an l-ribofuranoside benzimidazole, has been shown to be a potent and nontoxic inhibitor of EBV replication and to have a mode of action quite distinct from that of acyclic nucleoside analogs such as acyclovir (ACV) that is based primarily on MBV's ability to block the phosphorylation of target proteins by EBV and human cytomegalovirus protein kinases. However, since the antiviral mechanisms of the drug are complex, we have carried out a comprehensive analysis of the effects of MBV on the RNA expression levels of all EBV genes with a quantitative real-time reverse transcription-PCR-based array. We show that in comparisons with ACV, the RNA expression profiles produced by the two drugs are entirely different, with MBV causing a pronounced inhibition of multiple viral mRNAs and with ACV causing virtually none. The results emphasize the different modes of action of the two drugs and suggest that the action of MBV may be linked to indirect effects on the transcription of EBV genes through the interaction of BGLF4 with multiple viral proteins.

Successful prophylaxis with valaciclovir for relapsing HSV-1 in a girl treated with infliximab for moderate Crohn's disease

Biological agents such as inhibitors of tumour necrosis factor alpha (TNF-alpha ) are associated with the development of opportunistic infections. Although there are no international recommendations for the management of opportunistic infections, their prevention is a key safety issue for patients with inflammatory bowel disease (IBD). We report that chemoprophylaxis with oral valaciclovir was effective in preventing Herpes simplex virus (HSV-1) reactivation in a girl treated with infliximab for Crohn's disease.

Oral ganciclovir versus valganciclovir for cytomegalovirus prophylaxis in high-risk liver transplant recipients

This retrospective review compared oral valganciclovir (VGCV) 450 mg daily for 6 months versus oral ganciclovir (GCV) 1000 mg 3 times daily for 3 months in preventing cytomegalovirus (CMV) disease in high-risk liver transplant recipients.We evaluated all CMV donor positive-recipient negative liver transplant recipients managed at University Health System in San Antonio,Texas from August 1996 to September 2006. CMV disease was confirmed by polymerase chain-reaction or antigenemia assay, and CMV invasive disease by tissue biopsy. Patient demographics, laboratory results, complications, and therapies were collected via retrospective chart review. Patients < 18 years of age or those who died during transplant admission were excluded. Primary endpoints included incidence, onset, and severity of CMV disease up to 1 year post transplant. Data collection also included patient demographics, immunosuppression, CMV treatment regimens, and relevant lab results. A total of 64 patients (43 VGCV and 21 GCV) were identified. Four patients developed CMV disease:VGCV (3/43,7%) versus GCV (1/21, 5%) (P=1.0), with 1 VGCV patient experiencing tissue-invasive CMV. In all cases, onset of CMV disease occurred after prophylaxis was discontinued. Onset occurred at 24, 27, and 45 weeks post transplant in the VGCVgroup, and at 26 weeks in the 1 patient on GCV. Four patients received rabbit antithymocyte globulin (rATG) induction; 1 patient received rATG and developed CMV disease, with no statistical difference compared with the 3 remaining patients who received rATG but did not develop CMV disease (P=0.09). No difference was found in incidence of CMV disease between patients who received GCV and those who received VGCV at our institution.

Herpesviruses--a zoonotic threat?

Herpesviruses are highly host specific and share a long synchronous evolution with their hosts. Only in rare cases, species barriers fall and allow animal to human or human to animal transmission. Among the zoonotic herpesviruses, Cercopithecine herpesvirus 1 is the most significant and can be transmitted from macaques to human. Conversely, Human herpesvirus 1 is capable of causing severe disease in primates. Besides those two examples, there are several herpesviruses with a certainly limited or only suspected ability to cross species barriers. Those include Saimiriine herpesvirus 2, Phocid herpesvirus 2, Equid herpesvirus 1, Epstein-Barr Virus, Marek's disease virus, and Pseudorabies virus. Concerning xenotransplantations, porcine gammaherpesviruses must be considered as a zoonotic threat.

The implications of anti-tumour necrosis factor therapy for viral infection in patients with inflammatory bowel disease

INTRODUCTION

Anti-tumour necrosis factor (TNF) therapy is increasingly used in the management of inflammatory bowel disease; however, concerns have been raised regarding risk of infection with such drugs. Little is known about their effect upon viral infection.

SOURCES OF DATA

A search of PubMed using the terms 'infliximab', 'etanercept', 'adalimumab' or 'anti-TNF therapy' combined with the names of specific viruses was performed. A search of cited papers was used to identify further relevant reports.

AREAS OF AGREEMENT

Numerous reports of the use of anti-TNF in patients with chronic or latent viral infection appear in the literature. Specific problems related to hepatitis B virus and varicella zoster virus may exist. The safety profile of anti-TNF in chronic viral infection is generally reassuring.

AREAS OF CONTROVERSY

Numerous consensus statements relating to pre-treatment serology or vaccination have recently appeared; however, significant variation exists in their recommendations.

GROWING POINTS

Increasing awareness of the implications of anti-TNF therapy on viral infection may allow safer use of such drugs.

AREAS TIMELY FOR DEVELOPING RESEARCH

The clinical and cost-effectiveness of screening for viral infections prior to anti-TNF requires further study.

Human cytomegalovirus latent infection of myeloid cells directs monocyte migration by up-regulating monocyte chemotactic protein-1

Following primary infection, human cytomegalovirus (HCMV) establishes a latent infection in hematopoietic cells from which it reactivates to cause serious disease in immunosuppressed patients such as allograft recipients. HCMV is a common cause of disease in newborns and transplant patients and has also been linked with vascular diseases such as primary and post-transplant arteriosclerosis. A major factor in the pathogenesis of vascular disease is the CC chemokine MCP-1. In this study, we demonstrate that granulocyte macrophage progenitors (GMPs) latently infected with HCMV significantly increased expression of MCP-1 and that this phenotype was dependent on infection with viable virus. Inhibitors of a subset of G(alpha) proteins and PI3K inhibited the up-regulation of MCP-1 in latently infected cultures, suggesting that the mechanism underlying this phenotype involves signaling through a G-protein coupled receptor. In GMPs infected with the low passage viral strain Toledo, up-regulated MCP-1 was restricted to a subset of myeloid progenitor cells expressing CD33, HLA-DR, and CD14 but not CD1a, CD15, or CD16, and the increase in MCP-1 was sufficient to enhance migration of CD14(+) monocytes to latently infected cells. Latent HCMV-mediated up-regulation of MCP-1 provides a mechanism by which HCMV may contribute to vascular disease during the latent phase of infection or facilitate dissemination of virus upon reactivation from latency.

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.

Prophylaxis against Pneumocystis pneumonia in patients with inflammatory bowel disease: toward a standard of care

Patients with Crohn's Disease and ulcerative colitis are increasingly treated with a host of immunomodulatory and immunosuppressive medications, including thiopurines and antibody-based biologic agents. Despite the known infectious complications associated with these therapies from the HIV and solid organ transplant literature, there are currently no well-defined concise guidelines to assist gastroenterologists and other physicians in the utility and indication for prophylaxis against Pneumocystis pneumonia and other infections in inflammatory bowel disease (IBD) patients. In this article, we discuss the evidence of various infections associated with immunocompromise in HIV/AIDS, organ transplantation, and in other immunocompromised states, and discuss the evidence for the efficacy and safety of various infectious prophylaxis protocols. In addition, we discuss the evidence for Pneumocystis and other infections in IBD patients treated with corticosteroids, azathioprine/6-MP, biologic agents and other therapies, and we present the case for various antibiotic (and antiviral) regimens to prevent such infections. Based on the review of the literature, this discussion represents a true call for guidelines for infection prophylaxis, to help guide gastroenterologists and all practitioners who care for the challenging population of IBD patients.