Hellinger, Walter C.

AbstractIntroductionSolid organ transplant recipients have a higher frequency of tuberculosis (TB) than the general population, with mortality rates of approximately 30%. Although donor‐derived TB is reported to account for <5% of TB in solid organ transplants, the source of Mycobacterium tuberculosis infection is infrequently determined.MethodsWe report 3 new cases of pulmonary TB in lung transplant recipients attributed to donor infection, and review the 12 previously reported cases to assess whether cases could have been prevented and whether any cases that might occur in the future could be detected and investigated more quickly. Specifically, we evaluate whether opportunities existed to determine TB risk on the basis of routine donor history, to expedite diagnosis through routine mycobacterial smears and cultures of respiratory specimens early post transplant, and to utilize molecular tools to investigate infection sources epidemiologically.FindingsOn review, donor TB risk was present among 7 cases. Routine smears and cultures diagnosed 4 asymptomatic cases. Genotyping was used to support epidemiologic findings in 6 cases.ConclusionValidated screening protocols, including microbiological testing and newer technologies (e.g., interferon‐gamma release assays) to identify unrecognized M. tuberculosis infection in deceased donors, are warranted.

Intravascular catheters required for the care of many hospitalized patients can give rise to bloodstream infection, a complication of care that has occurred most frequently in intensive care unit (ICU) settings. Elucidation of the pathogenesis of catheter-related bloodstream infections (CRBSIs) has guided development of effective diagnostic, management, and prevention strategies. When CRBSIs occur in the ICU, physicians must be prepared to recognize and treat them. Prevention of these infections requires careful attention to optimal catheter selection, insertion and maintenance, and to removal of catheters when they are no longer needed. This review provides a succinct summary of the epidemiology, pathogenesis, and microbiology of CRBSIs and a review of current guidance for the diagnosis, management, and prevention of these infections.

AbstractBackgroundRecent studies have demonstrated that cytomegalovirus (CMV) infection and disease are associated with increased risk of graft loss and death in high‐risk (donor CMV seropositive/recipient CMV seronegative) liver transplant recipients (LTR) despite effective antiviral chemoprophylaxis. Predictors of CMV infection and disease in this important population are incompletely defined.MethodsA retrospective cohort study of 227 high‐risk first LTR who received primary anti‐CMV chemoprophylaxis during the first 100 days after transplant was performed. A large number of patient, donor, operative, and post‐transplant potential risk factors were collected. Associations of potential risk factors for CMV infection or disease that occurred during the first year after transplant were assessed using Cox regression models. After Bonferroni adjustment for multiple testing, P‐values ≤0.00125 (associations with CMV infection) and ≤0.00122 (associations with CMV disease) were considered as statistically significant.ResultsCMV infection and disease occurred in 91 (40%) and 43 (19%) of LTR, respectively. In multivariable analysis, increased risk of CMV infection was observed for patients with lower model for end‐stage liver disease (MELD) score (P = 0.025), lower total bilirubin (P = 0.014), and longer operative time (P = 0.038), whereas increased risk of CMV disease was seen in patients with lower MELD score (P = 0.026), lower total bilirubin (P = 0.044), and lower international normalized ratio (P = 0.043). However, after adjustment for multiple testing, none of these findings approached statistical significance.ConclusionOur results suggest that interventions designed to prevent CMV infection and disease should be applied to all high‐risk LTR until more definitive predictors of these complications are identified.

AbstractMycobacterium tuberculosis infection is one of many opportunistic infections in renal transplant recipients, arising either from reactivation of latent infection or de novo infection, occasionally donor derived. M. tuberculosis hepatitis has never been reported in patients who have received alemtuzumab as part of their renal transplant management. We describe 2 patients who underwent deceased‐donor renal transplantation following alemtuzumab induction therapy and presented with a febrile syndrome, subsequently diagnosed as tuberculous hepatitis, one with disseminated disease. Both responded well to treatment without significant side effects, resulting in excellent graft function. The importance of chemoprophylaxis should be emphasized to minimize the risk of developing active tuberculosis in patients with latent tuberculosis infection undergoing solid organ transplantation.

We studied the efficacy of continuous intravenous infusion of ampicillin compared with that of intermittent administration of ampicillin alone or in combination with gentamicin for the therapy of highly aminoglycoside-resistant enterococcal experimental endocarditis. Rabbits were infected with a gentamicin-susceptible (MIC, 256 micrograms/ml) strain of Enterococcus faecalis or a strain of E. faecalis which was highly resistant to gentamicin in vitro (MIC, greater than 2,000 micrograms/ml). Administration of ampicillin by continuous intravenous infusion did not significantly enhance the killing of enterococci in vivo compared with that by intermittent administration of ampicillin for either the aminoglycoside-susceptible or the aminoglycoside-resistant strain. In combination with gentamicin, there were no significant differences in efficacies obtained with intermittent versus continuous intravenous infusion of ampicillin therapy for experimental endocarditis caused by either strain of E. faecalis.

Patients coinfected with hepatitis C virus (HCV) and HIV undergoing liver transplantation (LT) are at risk of early, aggressive HCV recurrence. This study investigates the use of frequent protocol-driven biopsies to identify HCV recurrence post LT in coinfected patients. Five consecutive HIV/HCV-coinfected patients underwent LT. Liver biopsies were obtained post LT at 1 hour; days 7, 120, and 365; then annually; and as clinically indicated. Stage 2 (Ishak) or higher fibrosis occurred in 4 of the 5 patients by 60, 120, 270, and 365 days. Two patients died of HCV recurrence and liver failure at 6 and 35 months post LT. Three patients survived more than 4 years after LT, 2 having sustained virologic responses to anti-HCV treatment. Another has histologic recurrence not responding to treatment. Hepatitis C virus recurrence can be rapid and aggressive after LT in HIV-coinfected patients. Serial biopsies identify recurrence early, allowing for prompt initiation of treatment.