Varicella Infection in Adult Renal Allograft Recipients: Experience at One Center

Assessment of the herpes zoster risk among renal transplant recipients administered the influenza vaccine

BACKGROUND

Reactivation of the latent varicella-zoster virus can cause herpes zoster (HZ) infection, and renal transplant recipients undergoing immunosuppressive therapy are particularly susceptible to this condition. This study aims to evaluate the potential increase in HZ incidence following influenza vaccination among this specific patient population.

METHODS

This study was a population-based, retrospective, self-controlled case series. Data were retrieved from Taiwan's National Health Insurance Research Database spanning the years 2008 to 2017. Patients diagnosed with HZ within a 6-month period before and after receiving the influenza vaccine were eligible for inclusion. Two distinct time intervals were defined for analysis: the initial 15 days and 30 days following vaccination were categorized as risk intervals, while all other periods served as control intervals. Incidence rate ratios (IRRs) were computed to compare HZ incidence during the risk intervals with that during the control intervals.

RESULTS

This study encompassed a cohort of 4,222 renal transplant recipients who had received the influenza vaccine. Among this group, 67 recipients were subsequently diagnosed with HZ. The IRR during both the initial 15 days (IRR = 0.63; 95 % CI, 0.23-1.89) and the first 30 days (IRR = 1.50; 95 % CI, 0.71-3.16) following influenza vaccination did not demonstrate a statistically significant increase when compared to the post-exposure observation times. Comparable results were also observed when comparing these IRR values to the pre-exposure observation times. The subgroup analysis, stratified by age, sex, and underlying medical conditions (including cancer and autoimmune diseases), revealed that the IRRs did not exhibit statistically significant differences.

CONCLUSIONS

No significant association between the influenza vaccine and an elevated risk of HZ was detected. The administration of annual influenza vaccines appears to be a reasonable practice for renal transplant recipients.

Systematic Literature Review on the Incidence of Herpes Zoster in Populations at Increased Risk of Disease in the EU/EEA, Switzerland, and the UK

INTRODUCTION

Older adults and patients with underlying conditions such as immunocompromised (IC) populations (e.g., due to medical conditions or immunosuppressive medication) are at increased risk for herpes zoster (HZ). The first HZ recombinant vaccine for IC patients was approved in 2020. Limited evidence exists to inform decision-makers on HZ incidence in high-risk patients in Europe. This systematic literature review (SLR) assessed HZ incidence across 14 high-risk populations in the European Union/European Economic Area, Switzerland, and the United Kingdom.

METHODS

An SLR (Embase, Medline, 2002-2022, observational studies) was performed to identify HZ incidence (i.e., primary outcomes: rate or cumulative; secondary: relative incidence) in type 1 and 2 diabetes mellitus (DM); chronic obstructive pulmonary disease and asthma; depression; rheumatic disorders (RD); multiple sclerosis (MS); inflammatory bowel diseases (IBD); psoriasis; lupus; human immunodeficiency virus (HIV); solid organ transplantation (SOT); solid organ malignancy (SOM); hematologic malignancy (HM); and stem cell transplantation (SCT).

RESULTS

Of 776 unique records screened, 59 studies were included (24 reported incidence rate per 1000 person-years; two, cumulative incidence per 1000 persons; and 33, relative incidence). The highest incidence rates were reported for SOT (12.1-78.8) and SCT (37.2-56.1); HM (2.9-32.0); RD (0.41-21.5); lupus (11.0-16.5); IC mixed population (11.3-15.5); HIV/AIDS (11.8-13.0); chronic respiratory diseases (4.7-11.4); SOM (8.8-11.0); IBD (7.0-10.8); DM (4.3-9.4); depression (7.2-7.6); MS (5.7-6.3); and psoriasis (5.3-6.1). In many high-risk populations, HZ incidence was higher for older age groups, women, and some treatments.

CONCLUSIONS

The HZ incidence rate in Europe increased with age and varied across high-risk populations, with high rates for solid organ and stem cell transplants, cancer, and rheumatoid arthritis. Most studies were retrospective with methodological differences affecting generalizability and comparability. Future studies should stratify data by IC population, age, sex, severity, medication, and study timeframe.

Intravenous immunoglobulin in kidney transplantation: Mechanisms of action, clinical applications, adverse effects, and hyperimmune globulin

Intravenous immunoglobulin (IVIG) has been developed for over 40 years. The mechanisms of action of IVIG are complex and diverse, and there may be multiple mechanisms that combine to influence it. IVIG has been used in kidney transplantation for desensitization, treatment of antibody-mediated rejection, and ABO-incompatible transplantation. and treatment or prevention of some infectious diseases. Hyperimmune globulins such as cytomegalovirus hyperimmune globulin (CMV-IG) and hepatitis B hyperimmune globulin (HBIG) have also been used to protect against cytomegalovirus and hepatitis B virus, respectively. However, IVIG is also associated with some rare but serious adverse effects and some application risks, and clinicians need to weigh the pros and cons and develop individualized treatment programs to benefit more patients. This review will provide an overview of the multiple mechanisms of action, clinical applications, adverse effects, and prophylactic measures of IVIG, and hyperimmune globulin will also be introduced in it.

Serologic screening and infectious diseases consultation in renal transplant candidates for measles, mumps, rubella and varicella

Background. Renal transplant recipients are at increased risk for developing complications of vaccine-preventable diseases. They benefit from a comprehensive pre-transplant evaluation when they might safely receive live vaccines. The primary aim of our study was to investigate the number of renal transplant recipients who were evaluated for serologic status against measles, mumps, rubella (MMR), and varicella. Secondarily, we investigated if pre-transplant Infectious Diseases consultation (IDC) improved vaccination rates.Methods. We retrospectively analyzed 282 kidney-alone and kidney-plus adult transplant recipients who were born in or after 1957. Patients were evaluated at Mayo Clinic, Florida Transplant Center between January 2015 and December 2017. Serologic status evaluation and vaccination rates were compared in two groups created based on IDC and no ID consultation (NIDC).Results. 235 (83%) of a total 282 patients received an IDC pre-transplantation. Varicella IgG levels were screened in all 235 IDC candidates. Among the IDC patients, mumps, measles and rubella IgG serologies were performed in 7 (3%), 143 (61%) and 144 (61%), respectively. Among 44 patients seronegative for any of MMR, 24 (55%) were vaccinated. Ten (66%) of 15 varicella seronegative patients were vaccinated. Zostavax was not given to 18% of IDC patients. Zostavax and MMR were administered more frequently in the IDC group compared to NIDC (p < .001 and p = 0.0016, respectively).Conclusion. Although the majority of patients had IDC, the screening rate for MMR serologies was lower than varicella. A protocol-driven serologic screening similar to the one for VZV is required for MMR. Pre-transplant IDC increases vaccination rates.

Herpes Zoster in Solid Organ Transplantation: Incidence and Risk Factors

Background

Studies on herpes zoster (HZ) incidence in solid organ transplant (SOT) recipients report widely varying numbers. We investigated HZ incidence, severity, and risk factors in recipients of four different SOTs, with a follow-up time of 6-14 years.

Methods

Records of 1,033 transplant recipients after first heart (HTx: n = 211), lung (LuTx: n = 121), liver (LiTx: n = 258) and kidney (KTx: n = 443) transplantation between 2000 and 2014 were analyzed for VZV-PCR, clinical signs of HZ, and complications.

Results

HZ was diagnosed in 108 of 1,033 patients (10.5%): 36 HTx, 17 LuTx, 15 LiTx, and 40 KTx recipients. Overall HZ incidence rate after HTx (30.7 cases/1,000 person-years (PY)), LuTx (38.8 cases/1,000 PY), LiTx (22.7 cases/1,000 PY) and KTx (14.5 cases/1,000 PY) was significantly higher than in the general 50-70 year population. Multivariable analysis demonstrated age ≥50 years at transplantation (p = 0.038, RR 1.536), type of organ transplant (overall p = 0.002; LuTx p = 0.393; RR 1.314; LiTx p = 0.011, RR 0.444; KTx p = 0.034, RR 0.575), CMV prophylaxis (p = 0.043, RR 0.631) and type of anti-rejection therapy (overall p = 0.020; methylprednisolone p = 0.008, RR 0.475; r-ATG p = 0.64, RR1.194) as significant risk factors. Complications occurred in 33 of 108 (31%) patients (39% of HTx, 47% of LuTx, 20% of LiTx, 20% of KTx): post-herpetic neuralgia, disseminated disease, and cranial nerve involvement.

Conclusion

HZ incidence and severity in SOT recipients are most pronounced after heart and lung transplantation, in older patients, and when CMV prophylaxis is lacking.

Varicella zoster virus in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the American Society of Transplantation Infectious Diseases Community of Practice review the diagnosis, prevention, and management of varicella zoster virus (VZV) in the pre- and post-transplant period. Primary varicella is an uncommon complication post-solid-organ transplant (SOT), except among pediatric transplant patients and those seronegative for VZV. As the majority of SOT recipients are seropositive for VZV, herpes zoster (HZ) occurs frequently following SOT, particularly among recipients who are older (≥65 years of age) and those receiving more intensive immunosuppression. Transplant providers should aware of the increased risk for HZ-related complications such as dissemination, organ-specific involvement, and post-herpetic neuralgia. Treatment for localized zoster is primarily given as oral regimens, but those with more complicated presentations or those at risk for dissemination should be treated initially with IV therapy. Available antiviral prophylaxis regimens and vaccination strategies for varicella and HZ among these immunosuppressed patients remain a mainstay for prevention in the pre-and post-transplant periods. Finally, we discuss important approaches to addressing post-exposure prophylaxis and infection control practices for those SOT patients with documented VZV infections.

Current In Vivo Models of Varicella-Zoster Virus Neurotropism

Varicella-zoster virus (VZV), an exclusively human herpesvirus, causes chickenpox and establishes a latent infection in ganglia, reactivating decades later to produce zoster and associated neurological complications. An understanding of VZV neurotropism in humans has long been hampered by the lack of an adequate animal model. For example, experimental inoculation of VZV in small animals including guinea pigs and cotton rats results in the infection of ganglia but not a rash. The severe combined immune deficient human (SCID-hu) model allows the study of VZV neurotropism for human neural sub-populations. Simian varicella virus (SVV) infection of rhesus macaques (RM) closely resembles both human primary VZV infection and reactivation, with analyses at early times after infection providing valuable information about the extent of viral replication and the host immune responses. Indeed, a critical role for CD4 T-cell immunity during acute SVV infection as well as reactivation has emerged based on studies using RM. Herein we discuss the results of efforts from different groups to establish an animal model of VZV neurotropism.

Fatal disseminated visceral varicella zoster virus infection in a renal transplant recipient

We report a case of fatal disseminated varicella zoster virus (VZV) with delayed-onset rash in a 66-year-old female more than 2 years following uncomplicated deceased donor renal transplantation. Whilst on a stable regimen of maintenance immunosuppression, the patient presented with chest and abdominal pain with concomitant hepatitis and pancreatitis. After pursuing multiple other potential causes of her symptoms, the correct diagnosis of VZV was only suspected after the development of a widespread vesicular rash-11 days after her initial symptoms. Despite antiviral therapy and inotropic support in the intensive care unit, the patient died. Simultaneous VZV hepatitis and pancreatitis in solid organ transplant recipients is uncommon. The new inactivated VZV vaccines have the potential to prevent post-transplant infections, with promising early clinical data on safety and efficacy in renal transplant recipients. VZV is an important preventable infection that should be considered in immunocompromised patients, even in the absence of rash.

Systematic review of the evidence on the epidemiology of herpes zoster: incidence in the general population and specific subpopulations in Spain

OBJECTIVES

Herpes zoster (HZ) is an important cause of morbidity around the world, especially among the adult population aged >50 years.

STUDY DESIGN

A systematic review of the literature (up to October 31, 2016) was performed to identify available evidence on incidence of HZ in the general population and in a specific subpopulation in Spain.

METHODS

PubMed and Embase databases were searched, combining the following search terms: 'herpes zoster', 'diabetes mellitus (DM)', 'chronic obstructive pulmonary disease (COPD)', 'chronic heart failure', 'mental disorders' and 'immunocompromised'. Supplements for local scientific congresses, non-indexed Spanish journals and official epidemiological reports, potentially HZ related, were also manually searched. The inclusion criteria were the following: English or Spanish publications reporting incidence of HZ in the Spanish general population and/or specific subpopulations. No restrictions were applied on the study design or population age.

RESULTS

Among 269 references retrieved (48 PubMed, 148 Embase and 73 manual searching), 34 were finally included. Incidence of HZ in the general population ranged from 2.1 to 5.5/1000 person-years. HZ incidence ranged from 9.4 to 15.3/1000 patients with DM and from 11.0 to 11.4/1000 population with COPD or cardiovascular disease. In asthmatic patients, 6.9 HZ cases/1000 subjects were reported. The highest HZ incidence (1.3-400.0/1000 person-years) was in immunocompromised persons (10.0/1000 patients with cancer, 12.5/1000 patients with AIDS, from 5.0 to 240.0/1000 transplanted patients and from 6.6 to 27.0/1000 population with rheumatic diseases). Three studies estimated an increased risk of HZ in comparison with general population, for patients with DM (24%), COPD (39%) and COPD receiving inhaled corticosteroids (61%).

CONCLUSIONS

The results suggest a high risk of HZ in certain age groups and specific subpopulations. This study could contribute to identify target age populations and at-risk groups if implementation of HZ vaccination programmes in Spain would be considered.

Varicella infections in patients with end stage renal disease: a systematic review

BACKGROUND

End stage renal disease (ESRD) is on the rise globally. Varicella infection among adult patients with ESRD has been reported to lead to multiple complications and even death. While varicella vaccination has been recommended in paediatric renal patients; recommendation on varicella vaccination among adult patients with ESRD remained sparse. This review is aimed at evaluating the impact of varicella infection among adult patients with ESRD and make a recommendation for vaccination.

METHODS

Three databases (PubMed, Embase and Cumulative Index to Nursing and Allied Health Literature (CINAHL)) were searched in April 2018 with keywords 'varicella, chronic kidney failure, chronic kidney disease, renal replacement therapy, kidney transplantation, end stage renal disease, end stage renal failure, chicken pox, vaccine, vaccination and complications'.

RESULTS

29 articles were selected for review. The studies were mainly case reports, and they included measured outcomes: prevalence of seronegativity, impact (morbidity, length of stay, and mortality) of varicella among patients with ESRD, seroconversion rates and safety of varicella vaccination. The prevalence of seronegativity among varicella-infected ESRD adults was found to be at 42 to 100%. Nineteen deaths were reported. At least 54 patients have had complications from varicella infection. Seroconversion rate post vaccination was found to be around 64-94%.

CONCLUSION

Varicella is associated with significant morbidity and mortality rates in adult patients with ESRD. Varicella vaccination should be considered for the vulnerable, seronegative patients.

Herpes Zoster and Immunogenicity and Safety of Zoster Vaccines in Transplant Patients: A Narrative Review of the Literature

This narrative review focuses on the herpes zoster (HZ) and its prevention in transplant patients. Varicella zoster virus (VZV) is highly contagious and distributed worldwide in humans. Primary VZV infection usually causes varicella and then establishes a lifelong latency in dorsal root ganglia. Reactivation of VZV leads to HZ and related complications such as postherpetic neuralgia. Age and decreased immunity against VZV are important risk factors for developing HZ. Transplant patients are at increased risk for developing HZ and related complications due to their immunocompromised status and the need for lifetime immunosuppression. Diagnosis of HZ in transplant patients is often clinically difficult, and VZV-specific antibodies should be determined by serologic testing to document prior exposure to VZV during their pre-transplant evaluation process. Although antiviral agents are available, vaccination should be recommended for preventing HZ in transplant patients considering their complicated condition and weak organ function. Currently, there are two licensed HZ vaccines, of which one is a live-attenuated vaccine and the other is a HZ subunit vaccine. Both vaccines have shown promising safety and efficacy in transplants patients and especially the subunit vaccine could be administered post-transplant since this vaccine does not contain any live virus. Larger studies are needed about safety and immunogenicity of HZ vaccines in transplant populations, and extra efforts are needed to increase vaccine usage according to guidelines.

Incidence and mortality rates of varicella among end stage renal disease (ESRD) patients in Singapore General Hospital, a 12-year review

Background

End stage renal disease (ESRD)/ end stage renal failure (ESRF) is on the rise globally and especially in Singapore. Varicella or chickenpox is not uncommon among adults especially ESRD/ESRF patients. It has been reported to cause complications and even death among immunocompetent adults.

Methods

A retrospective data collection on patients with varicella infection and ESRD in Singapore General Hospital (SGH) from the year 2005 to 2016 was performed. Continuous data and categorical data were summarized as median (range) and count (%) respectively. The association of health care utilization (total length of hospital stay, readmission related to varicella, intensive care unit admission) and mortality with complication due to varicella were tested using chi-square and Mann-Whitney test for categorical and continuous outcomes respectively.

Results

Sixty-six patients with ESRD developed varicella during the study period (2005–2016). The case incidence rates for varicella among ESRD ranges from 97 to 267 per 100,000 populations with ESRD yearly. There were 9 deaths (13.6%). Mortality was higher among the ESRD patients with one or more varicella complications compared to patients without complications ((25% vs 7.1%, 95% CI for difference: − 1.1%, 36.9%, p = .063). Likewise, utilisation of intensive or high dependency units were higher among patients with complications compared to those without (20.8% vs 2.4%, 95% CI for difference: 1.6%, 35.3%, p = .012). Length of stay was twice as long in the group with complications compared to patients without (median (IQR) days: 14 (8, 21) vs 7 (5, 14), p = .065), although it did not reach statistical significance.

Conclusions

Varicella is associated with high morbidity and significant mortality rate in ESRD patients. Varicella vaccination is recommended for seronegative ESRD patients.

Fatal visceral disseminated varicella zoster infection during initial remission induction therapy in a patient with lupus nephritis and rheumatoid arthritis-possible association with mycophenolate mofetil and high-dose glucocorticoid therapy: a case report

BACKGROUND

Visceral disseminated varicella zoster viral (VZV) infection is a rare but severe complication with a high mortality rate in immunosuppressed individuals, and an increased susceptibility to VZV has been reported in kidney transplant recipients who are treated with mycophenolate mofetil (MMF). In Japan, MMF is currently approved for patients with lupus nephritis (LN) and data to indicate its optimal dosage are still insufficient.

CASE PRESENTATION

A 46-year-old Japanese woman with rheumatoid arthritis was diagnosed as having systemic lupus erythematosus (SLE) and LN class III (A/C). Although initial remission-induction therapy with prednisolone and tacrolimus was started, her serum creatinine level and urinary protein excretion were elevated. Methylprednisolone pulse therapy was added, and tacrolimus was switched to MMF. Two months after admission when she was taking 40 mg of PSL and 1500 mg of MMF daily, she suddenly developed upper abdominal pain and multiple skin blisters, and disseminated visceral VZV infection was diagnosed. Laboratory examinations demonstrated rapid exacerbation of severe acute liver failure and coagulation abnormalities despite immediate multidisciplinary treatment, and she died of hemorrhagic shock 7 days after the onset of abdominal pain. A serum sample collected at the time of admission revealed that she had recursive VZV infection.

CONCLUSIONS

MMF together with high-dose glucocorticoid therapy may increase the risk of VZV infection in Asian patients with SLE. Accumulation of evidence for parameters of safety, such as the area under the blood concentration-time curve of mycophenolic acid, should be urgently considered in order to establish a safer protocol for remission induction therapy in Asian patients with LN.

α Herpes Virus Infections Among Renal Transplant Recipients

The α herpes viruses HSV-1, HSV-2, and VZV often reactivate in the setting of immune suppression after solid organ transplantation. Oral or genital mucocutaneous disease is the most common clinical manifestation of HSV disease while VZV manifests as varicella (or chickenpox) or reactivation herpes zoster, characterized by a diffuse rash, or a painful unilateral vesicular eruption in a dermatomal distribution, respectively. The diagnosis of HSV and VZV is primarily based on history and clinical presentation, although diagnostic tests may be necessary for atypical presentations of disease. Treatment usually involves oral or intravenous antiviral therapy, depending on severity of illness.

Fatal case of cutaneous-sparing orolaryngeal zoster in a renal transplant recipient

Herpesvirus infections in solid organ transplant (SOT) recipients are a significant cause of morbidity and mortality. We report a case of herpes zoster (HZ) in a kidney transplant recipient while receiving belatacept, a CTLA-4 inhibitor that prevents acute rejection. The patient presented with oropharyngolaryngeal mucosal lesions that subsequently disseminated resulting in pneumonitis and meningo-encephalitis. Very late-onset HZ can occur and can present atypically in SOT recipients. Delayed recognition and treatment may result in poor outcomes, as illustrated by this case.

Practical Applications in Immunohistochemistry: Evaluation of Rejection and Infection in Organ Transplantation

CONTEXT

-Immunohistochemical analysis of tissue biopsy specimens is a crucial tool in diagnosis of both rejection and infection in patients with solid organ transplants. In the past 15 years, the concept of antibody-mediated rejection has been refined, and diagnostic criteria have been codified in renal, heart, pancreas, and lung allografts (with studies ongoing in liver, small intestine, and composite grafts), all of which include immunoanalysis for the complement split product C4d.

OBJECTIVES

-To review the general concepts of C4d biology and immunoanalysis, followed by organ-allograft-specific data, and interpretative nuances for kidney, pancreas, and heart, with discussion of early literature for lung and liver biopsies. Additionally, practical applications and limitations of immunostains for infectious organisms (Polyomavirus, Adenoviridae [adenovirus], and the herpes virus family, including Herpes simplex virus, Cytomegalovirus, Human herpes virus 8, and Epstein-Barr virus) are reviewed in the context of transplant recipients.

DATA SOURCES

-Our experience and published primary and review literature.

CONCLUSIONS

-Immunohistochemistry continues to have an important role in transplant pathology, most notably C4d staining in assessment of antibody-mediated rejection and assessment of viral pathogens in tissue. In all facets of transplant pathology, correlation of morphology with special studies and clinical data is critical, as is close communication with the transplant team.

Disseminated varicella zoster virus infection in adult renal transplant recipients: outcome and risk factors

BACKGROUND

Disseminated varicella zoster virus (VZV) infection, whether due to primary infection or reactivation, may be life threatening in renal transplant recipients. The aims of this study were to assess the outcome of disseminated VZV infection in renal transplant recipients and to determine potential risk factors for mortality.

METHODS

A search of the English literature from 1985 to 2011 using PUBMED was performed. Reports involving renal transplant recipients younger than 16 years of age were excluded.

RESULTS

A total of 56 adult patients presenting with a disseminated cutaneous or visceral VZV infection was included. Seventy percent of cases occurred within 5 years after transplantation, and 89% within 10 years. Visceral complications including disseminated intravascular coagulation occurred in two thirds of patients. Mortality decreased significantly from 47% in the era before 1995 to 17% after 1995 (P = .04). Risk factors for mortality included visceral involvement, use of azathioprine as immunosuppressant, and longer time between transplantation and VZV infection. VZV seropositivity did not influence fatal outcome.

CONCLUSION

Disseminated VZV infection can be life threatening in renal transplant recipients with a global mortality rate of 30%. This rate seems to have decreased since 1995. Seropositive VZV patients with disseminated infection are not protected from fatal outcome.

Varicella zoster infection in renal transplant recipients: prevalence, complications and outcome

Varicella zoster virus (VZV) is an important pathogen after renal transplantation. In the present study, we examined the prevalence, clinical presentation and outcome of VZV infections in renal transplant recipients. Charts and medical records of adult renal allotransplant recipients were investigated to find patients with VZV infection. From December 1972 until July 2010, 1,139 patients received kidney allograft at our institution. VZV infection was diagnosed in 40 patients (3.51%). 28 patients (70%) had intensified immunosuppression prior to VZV infection occurrence. Median time of onset was 2.13 years after transplantation (range 9 days to 19.2 years). 35 patients developed VZV during the first post-transplant year (median 0.61 years). Four patients developed VZV infection more than 12 years after transplantation. 33 patients (82.5%) had dermatomal distribution, 5 (12.5%) disseminated herpes zoster (HZ), and 2 patients (5%) who were VZV IgG-negative before transplantation, developed chickenpox. Immunosuppression was reduced and patients received acyclovir. Cutaneous scarring was recorded in 7 cases (17.5%). Two patients developed post-herpetic neuralgia, which was accompanied by scarring and skin depigmentation in 1 of them. Five patients (12.5%) experienced relapse of HZ. Timely initiation of therapy may prevent development of complications and the visceral form of disease. Based on our experience with development of chickenpox, we suggest active immunization for all seronegative patients before organ transplantation.

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.

KDIGO clinical practice guideline for the care of kidney transplant recipients

The 2009 Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guideline on the monitoring, management, and treatment of kidney transplant recipients is intended to assist the practitioner caring for adults and children after kidney transplantation. The guideline development process followed an evidence-based approach, and management recommendations are based on systematic reviews of relevant treatment trials. Critical appraisal of the quality of the evidence and the strength of recommendations followed the Grades of Recommendation Assessment, Development, and Evaluation (GRADE) approach. The guideline makes recommendations for immunosuppression, graft monitoring, as well as prevention and treatment of infection, cardiovascular disease, malignancy, and other complications that are common in kidney transplant recipients, including hematological and bone disorders. Limitations of the evidence, especially on the lack of definitive clinical outcome trials, are discussed and suggestions are provided for future research.