Transplant Infectious Disease

Abstract: Severe sepsis and progression to septic shock in solid organ transplant recipients is associated with a high mortality. We describe a fulminant case of septic shock in a liver transplant recipient caused by Pasteurella multocida, a gram‐negative coccobacillus most commonly associated with domestic cats and dogs. P. multocida is a rare cause of bacteremia and has not been reported as a cause of septic shock following liver transplantation. In addition to standard therapy, the patient was managed with drotrecogin alfa (activated) recombinant activated protein C (APC), an evidence‐based agent that has been shown to significantly improve outcome in severe sepsis in the non‐transplant population. The known risk factors, clinical course, and outcomes of severe infection associated with P. multocida are also briefly reviewed. This case illustrates the need for transplant recipients and their healthcare providers to carefully consider the risk of severe infection associated with domestic animal exposure.

This case describes a patient being considered for combined liver‐kidney transplantation for Caroli's disease with a failed renal transplant. A chronic septic focus could not be located with standard imaging techniques, such as ultrasonography and computed tomography. This case report highlights the observation that a retained non‐functioning transplant can be the cause of fever of unknown origin and PET‐CT can be useful in diagnosing these challenging cases.

Abstract: Human lactoferrin is a natural defense protein belonging to the innate immune system present in several body fluids and secretions, as well as in the secondary granules of polymorphonuclear neutrophils. Lactoferrin and its derivatives have pleiotropic functions including broad‐spectrum anti‐microbial activity, anti‐tumor activity, regulation of cell growth and differentiation, and modulation of inflammatory as well as humoral and cellular immune responses. This is the reason why much research has addressed the potential therapeutic activity of these molecules in different clinical settings, especially regarding infectious diseases and uncontrolled inflammatory conditions. In patients with hematological malignancies treated with a hematopoietic stem cell transplantation (HSCT), morbidity and mortality due to infections and uncontrolled inflammation remains high, despite many advances in supportive care. These life‐threatening complications are a result of the damage caused by the conditioning regimens to the mucosal barrier, and the innate and adaptive, humoral, and cellular immune defenses. These complications necessitate the continued exploration of new treatment modalities. Systemic and probably local levels of lactoferrin are decreased following HSCT. Therefore, the use of lactoferrin, or short peptide derivatives that retain the cationic N‐terminal moiety that is essential for the anti‐microbial and anti‐inflammatory activity, may prove to be a promising versatile class of agents for managing the complications that arise from HSCT.

Abstract: The recognition of the importance of Epstein–Barr virus (EBV) infection, including EBV‐associated post‐transplant lymphoproliferative disease (PTLD), has led to a new focus on the prevention of this problem. This paper reviews the scientific rationale behind, and clinical experience with, the use of chemoprophylaxis (using acyclovir or ganciclovir) and immunoprophylaxis (using intravenous immunoglobulin) in the prevention of EBV/PTLD. While some centers have already introduced the use of one or both of these agents as standard prophylaxis against the development of this complication, published data in support of these protocols are currently lacking. Well designed clinical trials are necessary to evaluate the potential role of both antiviral and immunoglobulin agents in the prevention of EBV/PTLD in organ transplant recipients.

Abstract: We identified 14 cases of Legionnaires' disease occurring in 2946 solid organ transplant recipients from 1985 to 2007. Most cases were sporadic and community acquired. The recent introduction of the urinary antigen test has accelerated diagnosis and allows prompt institution of adequate therapy. The overall mortality rate in our series was 14.3%.

Abstract: Background: Polyomavirus (primarily BK virus [BKV]) infection is an important cause of chronic renal dysfunction in renal transplant recipients, but its possible contribution to chronic renal dysfunction in non‐renal solid organ transplant (NRSOT) recipients has not been fully explored.

Methods: We performed a prospective, cross‐sectional study of consecutive NRSOT recipients with unexplained chronic renal dysfunction of at least a 3 months duration. Medical records were reviewed, and polymerase chain reaction was used to amplify BKV‐specific sequences from serum and urine samples. The potential associations between various demographic and transplant variables and BKV infection were assessed.

Results: Thirty‐four consecutive NRSOT recipients (23 lung, 8 liver, 2 heart, 1 heart–lung) with chronic renal dysfunction were enrolled at a median of 3.5 years (range 0.3–12.5 years) post transplantation. Five of the 34 (15%) patients had BKV viruria (range 1040–1.8 × 10⁶ copies/mL), but none had BKV viremia. BK viruria was associated with mycophenolate mofetil use (5 of 19 [26%] vs. 0 of 15, P=0.03) and a history of cytomegalovirus disease (3 of 4 [75%] vs. 2 of 30 [7%], P<0.01). However, the mean estimated creatinine clearance was similar in patients with or without BKV viruria (49 vs. 47 mL/min).

Conclusions: BKV viruria was present in a proportion of NRSOT patients with otherwise unexplained chronic renal dysfunction. The possibility that BKV infection might contribute to chronic renal dysfunction in this setting warrants further investigation.