Prevention of infection in adult travelers after solid organ transplantation

High-risk US international travelers seeking pretravel consultation during the COVID-19 pandemic

Background

To assess the implications of coronavirus disease 2019 (COVID-19)–related travel disruptions, we compared demographics and travel-related circumstances of US travelers seeking pretravel consultation regarding international travel at US Global TravEpiNet (GTEN) sites before and after the initiation of COVID-19 travel warnings.

Methods

We analyzed data in the GTEN database regarding traveler demographics and travel-related circumstances with standard questionnaires in the pre-COVID-19 period (January–December 2019) and the COVID-19 period (April 2020–March 2021), excluding travelers from January to March 2020. We conducted descriptive analyses of differences in demographics, travel-related circumstances, routine and travel-related vaccinations, and medications.

Results

Compared with 16 903 consultations in the pre-COVID-19 period, only 1564 consultations were recorded at GTEN sites during the COVID-19 period (90% reduction), with a greater proportion of travelers visiting friends and relatives (501/1564 [32%] vs 1525/16 903 [9%]), individuals traveling for >28 days (824/1564 [53%] vs 2522/16 903 [15%]), young children (6 mo–<6 y: 168/1564 [11%] vs 500/16 903 [3%]), and individuals traveling to Africa (1084/1564 [69%] vs 8049/16 903 [48%]). A smaller percentage of vaccine-eligible travelers received vaccines at pretravel consultations during the COVID-19 period than before, except for yellow fever and Japanese encephalitis vaccinations.

Conclusions

Compared with the pre-COVID-19 period, a greater proportion of travelers during the COVID-19 period were young children, were planning to visit friends and relatives, were traveling for >28 days, or were traveling to Africa, which are circumstances that contribute to high risk for travel-related infections. Fewer vaccine-eligible travelers were administered travel-related vaccines at pretravel consultations. Counseling and vaccination focused on high-risk international travelers must be prioritized during the COVID-19 pandemic.

Chronic Myeloid Leukemia in Children: Immune Function and Vaccinations

Children with CML need TKI treatment for many years, and the lack of knowledge about immune dysfunction with TKI has hindered routine immunizations. This review attempts to provide an overview of the effects of TKIs licensed for children (e.g., imatinib, dasatinib, and nilotinib) on immune function, as well as its implications on immunizations. We discuss surveillance strategies (e.g., immunoglobulin blood serum levels and hepatitis B reactivation) and immunizations. All inactivated vaccines (e.g., influenza, pneumococcal, and streptococcal) can be given during the treatment of CML in the chronic phase, although their efficacy may be lower. As shown in single cases of children and adults with CML, live vaccines (e.g., varicella, measles, mumps, rubella, and yellow fever) may be administered under defined circumstances with great precautions. We also highlight important aspects of COVID-19 in this patient population (e.g., the outcome of COVID-19 infection in adults with CML and in children with varying hemato-oncological diseases) and discuss the highly dynamic field of presently available different vaccination options. In conclusion, TKI treatment for CML causes humoral and cellular immune dysfunction, which is mild in most patients, and thus infectious complications are rare. Routine immunizations are important for health maintenance of children, but vaccinations for children with CML on TKI therapy should be carefully considered.

Methylene Blue Treatment of Grafts During Cold Ischemia Time Reduces the Risk of Hepatitis C Virus Transmission

Background

Although organ shortage is a rising problem, organs from hepatitis C virus (HCV) ribonucleic acid (RNA)-positive donors are not routinely transplanted in HCV-negative individuals. Because HCV only infects hepatocytes, other organs such as kidneys are merely contaminated with HCV via the blood. In this study, we established a protocol to reduce HCV virions during the cold ischemic time.

Methods

Standard virological assays were used to investigate the effect of antivirals, including methylene blue (MB), in different preservation solutions. Kidneys from mini pigs were contaminated with Jc1 or HCV RNA-positive human serum. Afterwards, organs were flushed with MB. Hypothermic machine perfusion was used to optimize reduction of HCV.

Results

Three different antivirals were investigated for their ability to inactivate HCV in vitro. Only MB completely inactivated HCV in the presence of all perfusion solutions. Hepatitis C virus-contaminated kidneys from mini pigs were treated with MB and hypothermic machine perfusion without any negative effect on the graft. Human liver-uPA-SCID mice did not establish HCV infection after inoculation with flow through from these kidneys.

Conclusions

This proof-of-concept study is a first step to reduce transmission of infectious HCV particles in the transplant setting and might serve as a model for other relevant pathogens.

Travel medicine, transplant tourism, and the solid organ transplant recipient-Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review recommendations for prevention and management of travel-related infection in solid organ transplant (SOT) recipients as well as risks associated with transplant tourism. Counseling regarding travel post-transplant should be included during the pre-transplant evaluation, and all SOT recipients should be seen by a travel medicine specialist prior to traveling to destinations with higher rates of infection. Patients should be advised on vaccine-preventable illnesses as well as any need for prophylaxis (ie, malaria) based on their individual travel itineraries. Information with regards to specific recommendations for vaccines and prophylactic medications, along with drug-drug interactions, is summarized. Counseling should be provided for modifiable risks and exposures (ie, food and water safety, and insect bite prevention) as well as non-infectious travel topics. These guidelines also briefly address risks associated with transplant tourism and specific infections to consider if patients seek care for transplants done in foreign countries.

Vaccinations in kidney transplant recipients: Clearing the muddy waters

Vaccine preventable diseases account for a significant proportion of morbidity and mortality in transplant recipients and cause adverse outcomes to the patient and allograft. Patients should be screened for vaccination history at the time of pre-transplant evaluation and vaccinated at least four weeks prior to transplantation. For non-immune patients, dead-vaccines can be administered starting at six months post-transplant. Live attenuated vaccines are contraindicated after transplant due to concern for infectious complications from the vaccine and every effort should be made to vaccinate prior to transplant. Since transplant recipients are on life-long immunosuppression, these patients may have lower rates of serological conversion, lower mean antibody titers and waning of protective immunity over shorter period as compared to general population. Recommendations regarding booster dose in kidney transplant recipients with sub-optimal serological response are lacking. Travel plans should be part of routine post-transplant assessment and pre-travel vaccines and counseling should be provided. More studies are needed on vaccination schedules, serological response, need for booster doses and safety of live attenuated vaccines in this special population.

Infection in Organ Transplantation

The prevention, diagnosis, and management of infectious disease in transplantation are major contributors to improved outcomes in organ transplantation. The risk of serious infections in organ recipients is determined by interactions between the patient's epidemiological exposures and net state of immune suppression. In organ recipients, there is a significant incidence of drug toxicity and a propensity for drug interactions with immunosuppressive agents used to maintain graft function. Thus, every effort must be made to establish specific microbiologic diagnoses to optimize therapy. A timeline can be created to develop a differential diagnosis of infection in transplantation based on common patterns of infectious exposures, immunosuppressive management, and antimicrobial prophylaxis. Application of quantitative molecular microbial assays and advanced antimicrobial therapies have advanced care. Pathogen-specific immunity, genetic polymorphisms in immune responses, and dynamic interactions between the microbiome and the risk of infection are beginning to be explored. The role of infection in the stimulation of alloimmune responses awaits further definition. Major hurdles include the shifting worldwide epidemiology of infections, increasing antimicrobial resistance, suboptimal assays for the microbiologic screening of organ donors, and virus-associated malignancies. Transplant infectious disease remains a key to the clinical and scientific investigation of organ transplantation.

Travel to High Altitude Following Solid Organ Transplantation

Luks, Andrew M. Clinician's corner: travel to high altitude following solid organ transplantation. High Alt Med Biol. 17:147-156, 2016.-As they regain active lifestyles following successful organ transplantation, transplant recipients may travel to high altitude for a variety of activities, including skiing, climbing, and trekking. This review is intended to provide information for medical providers who may encounter transplant patients seeking advice before planned high altitude travel or care for medical issues that develop during the actual sojourn. There is currently limited information in the literature about outcomes during high-altitude travel following solid organ transplantation, but the available evidence suggests that the physiologic responses to hypobaric hypoxia are comparable to those seen in nontransplanted individuals and well-selected transplant recipients with no evidence of organ rejection can tolerate ascents as high as 6200 m. All transplant recipients planning high-altitude travel should undergo pretravel assessment and counseling with an emphasis on the recognition, prevention, and treatment of altitude illness, as well as the importance of preventing infection and limiting sun exposure. Transplant recipients can use the standard medications for altitude illness prophylaxis and treatment, but the choice and dose of medication should take into account the patient's preexisting medication regimen and current renal function. With careful attention to these and other details, the healthy transplant recipient can safely experience the rewards of traveling in the mountains.

Organ Transplantation, Risks☆

Viruses are among the most common causes of opportunistic infection after solid organ and hematopoietic stem cell transplantation (SOT and HSCT). Viral infection is associated with both direct (invasive disease) and indirect (immune modulation) effects affecting susceptibility to other infections and promoting allograft rejection. The transplantation recipient is susceptible to a broad array of viral pathogens. Some may be transmitted with the allograft as donor-derived infections, while others result from exposure, either soon after the transplant or from more distant exposures when infection is latent and reactivates in the setting of immune suppression. Simultaneous infections with multiple viral or viral and nonviral pathogens are common. The risk for viral infection is a function of the intensity of exposure and virulence of the specific virus, the intensity of immune suppression used to prevent graft rejection or graft-versus-host disease, underlying immune deficits, and factors affecting host susceptibility. Studies of viral latency, reactivation, and of the cellular effects of viral infection will provide clues for future strategies in prevention and treatment of viral infections. This article covers specific issues relating to viral infection in SOT and HSCT; additional details regarding these viral infections are also found elsewhere in this text.

Travel risk assessment, advice and vaccinations in immunocompromised travellers (HIV, solid organ transplant and haematopoeitic stem cell transplant recipients): A review

International travellers with immunocompromising conditions such as human immunodeficiency virus (HIV) infection, solid organ transplantation (SOT) and haematopoietic stem cell transplantation (HSCT) are at a significant risk of travel-related illnesses from both communicable and non-communicable diseases, depending on the intensity of underlying immune dysfunction, travel destinations and activities. In addition, the choice of travel vaccinations, timing and protective antibody responses are also highly dependent on the underlying conditions and thus pose significant challenges to the health-care providers who are involved in pre-travel risk assessment. This review article provides a framework of understanding and approach to aforementioned groups of immunocompromised travellers regarding pre-travel risk assessment and management; in particular travel vaccinations, infectious and non-infectious disease risks and provision of condition-specific advice; to reduce travel-related mortality and morbidity.

Travel and transplantation: travel-related diseases in transplant recipients

PURPOSE OF REVIEW

Travel-related diseases may be seen in transplant recipients after travel, after transplant tourism, and via transmission from blood and organ donors, augmented by recent increases in travel, migration, and globalization. Such infections include tuberculosis, Plasmodium (malaria), Babesia, Trypanosoma cruzi (Chagas disease), Strongyloides, Coccidioides, Histoplasma, Leishmania, Brucella, HTLV, dengue, among numerous others.

RECENT FINDINGS

Review of cohorts of transplant recipients show that they tend to have minimal or suboptimal preparation prior to travel, with limited pretravel vaccination, medications, and education, which poses a greatly increased risk of travel-related infections and complications. The epidemiology of such travel-related infections in transplant recipients, along with methods for prevention, including vaccines, chemoprophylaxis, and education may help SOT recipients avoid travel-related infections, and are discussed in this review.

SUMMARY

Optimizing the understanding of the risk of tropical, geographically restricted, and other unusual or unexpected, travel-related infections will enhance the safety of vulnerable transplant recipients from potentially life-threatening infections.

The immunosuppressed traveler

This article reviews the normal immune response to vaccines. It describes the effect of different immunosuppressive therapies (glucocorticoids, inhibitors of calcineurin and mTOR, azathioprine, mycophenolate acid, methotrexate, depleting and nondepleting monoclonal antibodies, and tumor necrosis factor antagonists) on critical steps in the cellular and humoral immune responses to vaccines. The impact of age-related involution of thymus and bone marrow on the immune reconstitution in allogeneic hematopoietic cell transplant recipients and human immunodeficiency virus is covered. A practical approach to vaccinating and preparing travelers with severe immunosuppression is proposed.

Long-term outcome after liver transplantation

Liver transplantation is a life-saving therapy for patients with end-stage liver disease, acute liver failure, and liver tumors. Over the past 4 decades, improvements in surgical techniques, peritransplant intensive care, and immunosuppressive regimens have resulted in significant improvements in short-term survival. Focus has now shifted to addressing long-term complications and improving quality of life in liver recipients. These include adverse effects of immunosuppression; recurrence of the primary liver disease; and management of diabetes, hypertension, dyslipidemia, obesity, metabolic syndrome, cardiovascular disease, renal dysfunction, osteoporosis, and de novo malignancy. Issues such as posttransplant depression, employment, sexual function, fertility, and pregnancy must not be overlooked, as they have a direct impact on the liver recipient's quality of life. This review summarizes the latest data in long-term outcome after liver transplantation.

Parasitic infections in solid-organ transplant recipients

PURPOSE OF REVIEW

To provide an updated perspective of the most common parasitic infections occurring in solid-organ transplant (SOT) recipients.

RECENT FINDINGS

Parasitic infections are an emerging problem in SOT programs and represent a diagnostic and therapeutic challenge. Transplantation in endemic areas - including medical tourism, international travel and migration - justify the necessity of considering parasitic infections in the differential diagnosis of posttransplant complications. Molecular techniques, such as PCR, may improve the diagnostic accuracy and help during the follow-up.

SUMMARY

Parasitic infections are an uncommon but potentially severe complication in SOT recipients. An increase of donors emigrated from tropical areas and more posttransplant patients traveling to endemic areas have led to a rise in parasitic infections reported among SOT recipients. Transplant physicians should get familiar with parasitic infections and promote adherence to preventive measures in SOT recipients.

Global TravEpiNet: a national consortium of clinics providing care to international travelers--analysis of demographic characteristics, travel destinations, and pretravel healthcare of high-risk US international travelers, 2009-2011

BACKGROUND

 International travel poses a risk of destination-specific illness and may contribute to the global spread of infectious diseases. Despite this, little is known about the health characteristics and pretravel healthcare of US international travelers, particularly those at higher risk of travel-associated illness.

METHODS

 We formed a national consortium (Global TravEpiNet) of 18 US clinics registered to administer yellow fever vaccination. We collected data regarding demographic and health characteristics, destinations, purpose of travel, and pretravel healthcare from 13235 international travelers who sought pretravel consultation at these sites from January 2009 through January 2011.

RESULTS

 The destinations and itineraries of Global TravEpiNet travelers differed from those of the overall population of US international travelers. The majority of Global TravEpiNet travelers were visiting low- or lower-middle-income countries, and Africa was the most frequently visited region. Seventy-five percent of travelers were visiting malaria-endemic countries, and 38% were visiting countries endemic for yellow fever. Fifty-nine percent of travelers reported ≥1 medical condition. Atovaquone/proguanil was the most commonly prescribed antimalarial drug, and most travelers received an antibiotic for self-treatment of travelers' diarrhea. Hepatitis A and typhoid were the most frequently administered vaccines.

CONCLUSIONS

 Data from Global TravEpiNet provide insight into the characteristics and pretravel healthcare of US international travelers who are at increased risk of travel-associated illness due to itinerary, purpose of travel, or existing medical conditions. Improved understanding of this epidemiologically significant population may help target risk-reduction strategies and interventions to limit the spread of infections related to global travel.

Yellow fever vaccination in organ transplanted patients: is it safe? A multicenter study

BACKGROUND

Yellow fever (YF) may be very serious, with mortality reaching 50%. Live attenuated virus YF vaccine (YFV) is effective, but may present, although rare, life-threatening side effects and is contraindicated in immunocompromised patients. However, some transplant patients may inadvertently receive the vaccine.

METHODS

A questionnaire was sent to all associated doctors to the Brazilian Organ Transplantation Association through its website, calling for reports of organ transplanted patients who have been vaccinated against YF.

RESULTS

Twelve doctors reported 19 cases. None had important side effects. Only one had slight reaction at the site of YFV injection. Eleven patients were male. Organs received were 14 kidneys, 3 hearts, and 2 livers. Twelve patients received organs from deceased donors. Mean age at YFV was 45.6 ± 13.6 years old (range 11-69); creatinine: 1.46 ± 0.62 mg/dL (range 0.8-3.4); post-transplant time: 65 ± 83.9 months (range 3-340); and time from YFV at the time of survey: 45 ± 51 months (range 3-241). Immunosuppression varied widely with different drug combinations: azathioprine (7 patients), cyclosporine (8), deflazacort (1), mycophenolate (10), prednisone (11), sirolimus (3), and tacrolimus (4).

CONCLUSIONS

YFV showed no important side effects in this cohort of solid organ transplanted patients. However, owing to the small number of studied patients, it is not possible to extend these findings to the rest of the transplanted population, assuring safety. Therefore, these data are not strong enough to safely recommend YFV in organ transplanted recipients, as severe, even life-threatening side effects may occur.

Parasitic infections in solid organ transplant recipients

Parasitic infections are an uncommon but potentially severe complication in solid organ transplant (SOT) recipients. An increase in donors who have emigrated from tropical areas and more transplant recipients traveling to endemic areas have led to a rise in parasitic infections reported among SOT recipients. Clinicians should include these infections in their differential diagnosis and promote adherence to preventive measures in SOT recipients.

Successful immunization of an allogeneic bone marrow transplant recipient with live, attenuated yellow Fever vaccine

Vaccination against yellow fever is effective, but available live virus vaccines are not recommended for use in immunocompromised or elderly patients. We report the successful and uneventful immunization of a 62-year-old man with a history of allogeneic bone marrow transplant and discuss evidence for this recommendation.

Transplantation and tropical infectious diseases

The number of transplant recipients with tropical infectious diseases is growing due to increasing international travel and the rising number of transplants taking place in the tropics and subtropics. With increases in population migration, the prevalence of individuals infected with geographically restricted organisms also rises. There are three potential categories of tropical infections in transplant patients: (1) donor-related infections transmitted by the graft or through transfusion of blood products; (2) reactivation or recrudescence of latent infections in the donor recipient; and (3) de novo acquisition of infection in the post-transplant period through the traditional route of infection. We present an overall discussion of the association of parasitic (protozoa and helminths) and non-parasitic (viral, bacterial, and fungal) tropical infectious diseases and solid-organ and hematopoietic transplantation. We also suggest potential screening guidelines for some of these tropical infections.

[Recommendations before travelling for renal transplant patients]

Travel is now a reasonable objective of CKD patients after renal transplantation. However, immunosuppressive treatment makes them particularly susceptible to infections and may interfere with vaccinations and other drugs. Travel in countries with low health level should be strongly discouraged in the first six months after transplantation or following an acute event. Otherwise, specific consultations should be arranged to prepare the patient as soon as possible. Vaccinations should be started early before departure. Specific immunisations include vaccines against hepatitis A, typhoid, meningococcus and rabies in some cases. Living vaccines are formally contra-indicated. Particular attention should be paid for protection against insects because this is the only effective measure against diseases. In the case of malaria, it should be complemented by adapted chemoprophylaxis that should be started 15 days before the departure date. Advice on hygiene measures should be clarified because this can prevent numerous infections, especially of the digestive tract. Advice on the management of diarrhoea is essential, especially in terms of preventing dehydration. Finally, advice about transport and physical risks, especially those related to sun exposure, should also be addressed.

Management of the kidney transplant recipient

The short-term outcomes of kidney transplant recipients have improved dramatically in the past 20 years, in large part resulting from the availability of more potent immunosuppressive drugs capable of preventing or treating acute allograft rejection. Ironically, side effects from these same immunosuppressants play a role in the long-term morbidity and mortality of this patient population. As kidney transplant recipients survive for longer periods of time with functioning allografts, primary care physicians will likely become more involved in their management, mandating at least a basic understanding of immunosuppression and its complications.

International travel and exposure risks in solid-organ transplant recipients

BACKGROUND

Although solid-organ transplant recipients (SOTR) have an increased risk of acquiring illnesses, they may not receive optimal pretravel care. We conducted a cross-sectional survey of travel activities and outcomes among SOTR.

METHODS

Two thousand five hundred fifty-four consecutive living SOTR from Mayo Clinic were surveyed regarding travel practices, pretravel counseling, exposure risks, and illness using a previously standardized and validated questionnaire.

RESULTS

One thousand one hundred thirty SOTR (44%) responded to the survey and were included in the study. The most common transplanted organs were liver (519 patients) and kidney (515 patients). Three hundred and three (27%) respondents reported travel outside of the United States or Canada after their transplant. Liver recipients were more likely to travel than other organ recipients. Ninety-six percent of travelers reported that they did not seek specific pretravel healthcare before their trip. Forty-nine SOTR (16%) traveled to destinations at higher risk for infectious diseases; travelers to these destinations were more likely to be men (73% vs. 54% of low-infection risk travelers, P=0.018) or born outside the United Stated or Canada (29% vs. 6% P<0.0001). Twenty-four travelers (8%) required medical attention because of illness; illness was more likely among travelers to high-infection risk (18%) than low-risk (6%) destinations, P=0.004.

CONCLUSIONS

International travel was common after solid organ transplantation, although the majority traveled to destinations at low risk for infectious disease. Although generally SOTR were able to travel safely, travelers to destinations at high-risk for infection had a significant rate of illness. Pretravel counseling and interventions were infrequent and should be improved.

Vaccination of the solid organ transplant recipient

Active immunization is the most important way to protect immunocompromised patients from vaccine-preventable infectious diseases. Although live vaccines are contraindicated for most immunocompromised patients, many inactivated or conjugate vaccines are safe and generally recommended. Some vaccines are known to be of suboptimal immunogenicity in transplant recipients. As a consequence, this may be associated with an impaired ability to mount protective immunity. Nevertheless, even partial protection has been shown to confer significant benefit to this vulnerable patient group. To increase efficacy in generating protective immunity, patients should complete the full complement of recommended vaccinations early in the course of disease before transplantation. This review summarizes the general recommendations for vaccinations of adult transplant recipients and candidates including special considerations for household contacts and health care workers.

Update on immunizations in solid organ transplant recipients: what clinicians need to know

Vaccine-preventable diseases remain a major source of morbidity and mortality in transplant recipients. Since the publication of the American Society of Transplantation's guidelines for vaccination of solid organ transplant recipients in 2004 (1), several new vaccines have been licensed. Transplant clinicians have been inundated by questions from patients and colleagues regarding the utility and safety of these vaccines in transplant candidates and recipients. In addition, new data has appeared regarding utility of some established vaccines, lack of rejection after vaccination and newer adjuvant strategies. Literature published between 2004 and 2007 was reviewed in a Medline search. Guidelines from the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices are reviewed and summarized, with particular attention to vaccines for human papillomavirus, varicella and varicella-zoster, tetanus-reduced diphtheria-acellular pertussis (Tdap) and hepatitis B, as well as conjugated meningococcal and conjugated pneumococcal vaccines. Although randomized controlled trials in transplant recipients have not been performed for most new licensed vaccines, preliminary recommendations can be formulated based on current data and guidelines. Further studies will be important to determine the indications and optimal timing of newer immunizations and immunization strategies.

Health preparations and travel-related morbidity of kidney transplant recipients traveling to developing countries

A cross-sectional, descriptive study was conducted among Dutch kidney transplant recipients to investigate travel health knowledge, attitudes and practices while staying abroad. A total of 290 individuals visiting the nephrology outpatient clinic completed the questionnaires. Thirty four percent of the responders had traveled outside Western Europe (WE) and Northern America (NA); 22% of these travelers did not seek pre-travel health advice. Transplant physicians were most frequently consulted for pre-travel advice (53%). Of the responders traveling outside WE and NA 29% were ill during their most recent journey. Diabetic transplant recipients were at the highest risk. Four of seventeen ill recipients (24%) were hospitalized, reflecting the high morbidity of travel-related disease in this patient group. Our data show that there is need for improvement of pre-travel healthcare, and suggest an important role for transplant physicians in providing adequate counseling.

Zoonoses in Solid-Organ and Hematopoietic Stem Cell Transplant Recipients

Numerous reports exist of the transmission of zoonoses to humans during and after solid-organ and hematopoietic stem cell transplantation. Donor-derived infections of numerous etiologies, including West Nile virus infection, Chagas disease, toxoplasmosis, rabies, lymphocytic choriomeningitis virus infection, and infection due to Brucella species have been reported. Most zoonoses occur as a primary infection after transplantation, and immunocompromised patients are more likely to experience significant morbidity and mortality from these infections. Risks of zoonotic infection in the posttransplantation period could be reduced by patient education. Increased recognition of the risks of zoonoses, as well as the advent of molecular biology-based testing, will potentially augment diagnostic aptitude. Documented zoonotic infection as it affects transplantation will be the primary focus of this review.

Prevention and treatment of travel-related infections in compromised hosts

PURPOSE OF REVIEW

The numbers of international travelers and complexity of their underlying medical conditions continue to increase. Traveling with compromised immunity warrants special consideration regarding the prevention and treatment of travel-related diseases, ideally with the help of a travel medicine specialist. There is a need for careful weighing of the potential health risks in persons with severe immunosuppression, including that related to HIV, use of immunomodulating agents, malignancy and cancer chemotherapy, solid organ and bone marrow transplantation, and asplenia.

RECENT FINDINGS

Over the past year, a number of articles and texts have been published addressing the health risks and management strategies for travelers with underlying immune compromise, including the potential interactions between HIV and malaria, and transplant outcomes for those receiving transplants through medical tourism.

SUMMARY

Tailored advice and treatment strategies for compromised travelers can help facilitate safe travel for individuals who choose risk-taking travel.

Long-term patient survival: strategies to improve overall health

The use of potent immunosuppressant therapy has led to an increase in number of patients with successful long-term kidney transplants. These individuals come to kidney transplantation with varying levels of comorbidity associated with end-stage renal disease and are susceptible to immunologic and nonimmunologic comorbidities that arise late after transplantation, including cardiovascular disease, infection, malignancy, and bone disease, which negatively impact on patient and graft survival. In addition, nonadherence to immunosuppressant regimens increases with time after transplantation, which further augments the risk for late-term graft failure and mortality. Consistent and frequent follow-up of kidney transplant recipients beyond the first year permits early diagnosis and successful treatment of many posttransplantation comorbidities. Implementation of preventive practices and aggressive management of risk factors throughout the life of the transplant improves overall health and long-term outcomes. Establishment and maintenance of close relationships among transplant centers, physicians, patients, and their families improves patient adherence to medications and reduces the risk for morbidity and mortality.

Medical Care of Kidney Transplant Recipients after the First Posttransplant Year

Kidney transplantation is the treatment of choice for patients with ESRD. Despite improvements in short-term patient and graft outcomes, there has been no major improvement in long-term outcomes. The use of kidney allografts from expanded-criteria donors, polyoma virus nephropathy, underimmunosuppression, and incomplete functional recovery after rejection episodes may play a role in the lack of improvement in long-term outcomes. Other factors, including cardiovascular disease, infections, and malignancies, also shorten patient survival and therefore reduce the functional life of an allograft. There is a need for interventions that improve long-term outcomes in kidney transplant recipients. These patients are a unique subset of patients with chronic kidney disease. Therefore, interventions need to address disease progression, comorbid conditions, and patient mortality through a multifaceted approach. The Kidney Disease Outcomes Quality Initiative from the National Kidney Foundation, the European Best Practice Guidelines, and the forthcoming Kidney Disease: Improving Global Outcomes clinical practice guidelines can serve as a cornerstone of this approach. The unique aspects of chronic kidney disease in the transplant recipient require the integration of specific transplant-oriented problems into this care schema and a concrete partnership among transplant centers, community nephrologists, and primary care physicians. This article reviews the contemporary aspects of care for these patients.

Gastrointestinal infections in immunocompromised hosts

PURPOSE OF REVIEW

Gastrointestinal infections in the immunocompromised host continue to have significant morbidity and mortality throughout the world. They all have similar exposures to viruses, bacteria and parasites and respond to these infections in a similar way. This review will summarize the latest reports on the epidemiology, diagnosis and treatment of known and emerging infections over the last 12 months.

RECENT FINDINGS

Highly active antiretroviral therapy has reduced esophageal opportunistic infections in HIV patients compared to patients who are not taking this therapy. Esophageal candidiasis responds to escalating doses of micafungin as effectively as fluconazole. HIV-infected patients with untreated Mycobacterium avium-complex diarrhea are associated with a wasting syndrome that disrupts the somatostatin axis. Polymerase chain reaction testing has improved diagnosis of microsporidial infections. Cytomegalovirus polymerase chain reaction of tissue may improve the diagnosis of cytomegalovirus disease of the gastrointestinal tract in organ-transplant recipients. The treatment of hypogammaglobulinemia in transplant recipients with recurrent cytomegalovirus gastrointestinal disease may resolve their symptoms. Community viruses are an emerging threat to transplant recipients and may affect drug levels. Lastly, anti-tumor necrosis factor alpha therapy in the treatment of inflammatory conditions may cause Listeria monocytogenes to disseminate.

SUMMARY

Immunocompromised hosts remain at risk for severe gastrointestinal and even disseminated infections. Management includes an early rapid diagnosis with rapid restoration of the immune system and appropriate anti-infective therapy. With the immunocompromised population rapidly increasing, prevention of these infections remains the greatest challenge.