Successful use of azithromycin for Escherichia coli–associated renal allograft malakoplakia: a report of two cases

European Journal of Clinical Microbiology & Infectious Diseases - Malakoplakia is a chronic granulomatous disease associated with incomplete clearance of bacterial pathogens. A multimodal...     

Solid Organ Transplantation From Hepatitis B Virus–Positive Donors: Consensus Guidelines for Recipient Management

Use of organs from donors testing positive for hepatitis B virus (HBV) may safely expand the donor pool. The American Society of Transplantation convened a multidisciplinary expert panel that reviewed the existing literature and developed consensus recommendations for recipient management following the use of organs from HBV positive donors. Transmission risk is highest with liver donors and significantly lower with non‐liver (kidney and thoracic) donors. Antiviral prophylaxis significantly reduces the rate of transmission to liver recipients from isolated HBV core antibody positive (anti‐HBc+) donors. Organs from anti‐HBc+ donors should be considered for all adult transplant candidates after an individualized assessment of the risks and benefits and appropriate patient consent. Indefinite antiviral prophylaxis is recommended in liver recipients with no immunity or vaccine immunity but not in liver recipients with natural immunity. Antiviral prophylaxis may be considered for up to 1 year in susceptible non‐liver recipients but is not recommended in immune non‐liver recipients. Although no longer the treatment of choice in patients with chronic HBV, lamivudine remains the most cost‐effective choice for prophylaxis in this setting. Hepatitis B immunoglobulin is not recommended.     

The risk of tuberculosis in transplant candidates and recipients: a TBNET consensus statement

Tuberculosis (TB) is a possible complication of solid organ and hematopoietic stem cell transplantation. The identification of candidates for preventive chemotherapy is an effective intervention to protect transplant recipients with latent infection with Mycobacterium tuberculosis from progressing to active disease. The best available proxy for diagnosing latent infection with M. tuberculosis is the identification of an adaptive immune response by the tuberculin skin test or an interferon-γ based ex vivo assay. Risk assessment in transplant recipients for the development of TB depends on, among other factors, the locally expected underlying prevalence of infection with M. tuberculosis in the target population. In areas of high prevalence, preventive chemotherapy for all transplant recipients may be justified without immunodiagnostic testing while in areas of medium and low prevalence, preventive chemotherapy should only be offered to candidates with positive M. tuberculosis-specific immune responses. The diagnosis of TB in transplant recipients can be challenging. Treatment of TB is often difficult due to substantial interactions between anti-TB drugs and immunosuppressive medications. This management guideline summarises current knowledge on the prevention, diagnosis and treatment of TB related to solid organ and hematopoietic stem cell transplantation and provides an expert consensus on questions where scientific evidence is still lacking.     

Diagnosis and Management of Tuberculosis in Transplant Donors: A Donor‐Derived Infections Consensus Conference Report†

Mycobacterium tuberculosis is a ubiquitous organism that infects one‐third of the world's population. In previous decades, access to organ transplantation was restricted to academic medical centers in more developed, low tuberculosis (TB) incidence countries. Globalization, changing immigration patterns, and the expansion of sophisticated medical procedures to medium and high TB incidence countries have made tuberculosis an increasingly important posttransplant infectious disease. Tuberculosis is now one of the most common bacterial causes of solid‐organ transplant donor‐derived infection reported in transplant recipients in the United States. Recognition of latent or undiagnosed active TB in the potential organ donor is critical to prevent emergence of disease in the recipient posttransplant. Donor‐derived tuberculosis after transplantation is associated with significant morbidity and mortality, which can best be prevented through careful screening and targeted treatment. To address this growing challenge and provide recommendations, an expert international working group was assembled including specialists in transplant infectious diseases, transplant surgery, organ procurement and TB epidemiology, diagnostics and management. This working group reviewed the currently available data to formulate consensus recommendations for screening and management of TB in organ donors.     

Safety and immunogenicity of attenuated Salmonella enterica serovar Typhimurium delivering an HIV-1 Gag antigen via the Salmonella Type III secretion system

BACKGROUND: CKS257 (Salmonella typhimurium SL1344 DeltaphoP/phoQDelta aroA Deltaasd DeltastrA/strB pSB2131) is a live oral vaccine vector expressing HIV Gag. METHODS: HIV Gag was expressed as a fusion protein of a Salmonella Type III secretion system protein SopE, from a balanced lethal asd-based plasmid. Eighteen healthy adults were given single escalating oral doses of 5 x 10(6) to 1 x 10(10)CFU of CKS257 and were monitored for clinical events, shedding and immune responses. RESULTS: Adverse events were mild except at the highest dose. Volunteers shed the organism an average of 5.1 days (range 0-13 days). Eighty-three percent (15/18) of subjects had a mucosal immune response to Salmonella LPS and flagella by IgA ELISPOT assay. Seventy-two percent (13/18) of subjects seroconverted to Salmonella antigens. No volunteer had a response to recombinant Gag as measured by serology, IgA ELISPOT, or immediate ex vivo gamma-interferon ELISPOT response to Gag peptide pools. Two volunteers responded to Gag peptides by IL-2 ELISPOT, and 4 of 10 volunteers receiving >or=5 x 10(8)CFU had a response to HIV peptides in a cultured gamma-interferon ELISPOT assay. CONCLUSIONS: Although immunogenicity of the HIV antigen needs augmentation, the attenuated Salmonella strain proved to be an excellent platform for vaccine development.     

Influenza vaccination in the organ transplant recipient: review and summary recommendations

Influenza virus causes a spectrum of illness in transplant recipients with a high rate of lower respiratory disease. Seasonal influenza vaccination is an important public health measure recommended for transplant recipients and their close contacts. Vaccine has been shown to be safe and generally well tolerated in both adult and pediatric transplant recipients. However, responses to vaccine are variable and are dependent on various factors including time from transplantation and specific immunosuppressive medication. Seasonal influenza vaccine has demonstrated safety and no conclusive evidence exists for a link between vaccination and allograft dysfunction. Annually updated trivalent inactivated influenza vaccines have been available and routinely used for several decades, although newer influenza vaccination formulations including high-dose vaccine, adjuvanted vaccine, quadrivalent inactivated vaccine and vaccine by intradermal delivery system are now available or will be available in the near future. Safety and immunogenicity data of these new formulations in transplant recipients requires investigation. In this document, we review the current state of knowledge on influenza vaccines in transplant recipients and make recommendations on the use of vaccine in both adult and pediatric organ transplant recipients.     

Vaccination and immunization against travel-related diseases in immunocompromised hosts

Immunocompromised hosts are growing in number and include transplant recipients of solid organs or hematopoietic stem cells, people who have HIV, cancer patients on chemotherapy, patients on immunomodulatory treatments for rheumatologic, gastrointestinal or other conditions, as well as those with other immunocompromising conditions. As their overall health improves, they are more likely to initiate foreign travel and have potential exposures to endemic pathogens. Immunocompromised hosts are, in general, less likely to respond to vaccines and may be more likely to have side effects from certain vaccines, such as those containing live-attenuated virus. In addition, vaccines are immunomodulatory and could theoretically impact upon immunologic conditions. This review will summarize the medical literature regarding travel-related vaccines in the adult, immunocompromised-host population. Since the research in this realm is limited and exists primarily in the setting of solid-organ and hematopoietic stem cell transplant recipients and HIV-positive subjects, this review will largely focus on these populations.