Randomized, double-blind trial of anidulafungin versus fluconazole for prophylaxis of invasive fungal infections in high-risk liver transplant recipients

Invasive fungal infections (IFIs) are a common complication in liver transplant recipients. There are no previous randomized trials of an echinocandin for the prevention of IFIs in solid organ transplant recipients. In a randomized, double-blind trial conducted at University-affiliated transplant centers, 200 high-risk liver transplant recipients (100 patients per group) received either anidulafungin or fluconazole for antifungal prophylaxis. Randomization was stratified by Model for End-Stage Liver Disease score ≥30 and receipt of a pretransplant antifungal agent. The primary end point was IFI in a modified intent-to-treat analysis. The overall incidence of IFI was similar for the anidulafungin (5.1%) and the fluconazole groups (8.0%) (OR 0.61, 95% CI 0.19-1.94, p = 0.40). However, anidulafungin prophylaxis was associated with less Aspergillus colonization or infection (3% vs. 9%, p = 0.08), lower breakthrough IFIs among patients who had received pretransplant fluconazole (0% vs. 27%, p = 0.07), and fewer cases of antifungal resistance (no cases vs. 5 cases). Both drugs were well-tolerated. Graft rejection, fungal-free survival, and mortality were similar for both groups. Thus, anidulafungin and fluconazole have similar efficacy for antifungal prophylaxis in most liver transplant recipients. Anidulafungin may be beneficial if the patient has an increased risk for Aspergillus infection or received fluconazole before transplantation.

A patient self-collection method for longitudinal monitoring of respiratory virus infection in solid organ transplant recipients

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We evaluate self-collection of nasal swabs using a longitudinal study design.

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Self-collected nasal swabs are feasible in solid organ transplant recipients.

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Self-collected nasal swabs are acceptable to solid organ transplant recipients.

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Self-collected nasal swabs are convenient to longitudinally study respiratory viruses.

Background

Methods for the longitudinal study of respiratory virus infections are cumbersome and limit our understanding of the natural history of these infections in solid organ transplant (SOT) recipients.

Objectives

To assess the feasibility and patient acceptability of self-collected foam nasal swabs for detection of respiratory viruses in SOT recipients and to define the virologic and clinical course.

Study design

We prospectively monitored the course of symptomatic respiratory virus infection in 18 SOT patients (14 lung, 3 liver, and 1 kidney) using patient self-collected swabs.

Results

The initial study sample was positive in 15 patients with the following respiratory viruses: rhinovirus (6), metapneumovirus (1), coronavirus (2), respiratory syncytial virus (2), parainfluenza virus (2), and influenza A virus (2). One hundred four weekly self-collected nasal swabs were obtained, with a median of 4 samples per patient (range 1–17). Median duration of viral detection was 21 days (range 4–77 days). Additional new respiratory viruses detected during follow-up of these 15 patients included rhinovirus (3), metapneumovirus (2), coronavirus (1), respiratory syncytial virus (1), parainfluenza virus (1), and adenovirus (1). Specimen collection compliance was good; 16/18 (89%) patients collected all required specimens and 79/86 (92%) follow-up specimens were obtained within the 7 ± 3 day protocol-defined window. All participants agreed or strongly agreed that the procedure was comfortable, simple, and 13/14 (93%) were willing to participate in future studies using this procedure.

Conclusion

Self-collected nasal swabs provide a convenient, feasible, and patient-acceptable methodology for longitudinal monitoring of upper respiratory virus infection in SOT recipients.

Challenging issues in tuberculosis in solid organ transplantation

Solid organ transplant (SOT) recipients are at risk for opportunistic infections including tuberculosis. Although guidelines on the management of latent tuberculosis and active tuberculosis are available, there remain a number of clinical areas with limited guidance. We discuss challenges in the diagnosis, management, and treatment of latent and active tuberculosis in SOT candidates and recipients who reside in low-tuberculosis-prevalence areas. We discuss the diagnosis of latent tuberculosis in SOT candidates/recipients using tuberculin skin tests and interferon-γ release assays and risk stratification of SOT candidates/recipients that would identify individuals at high risk for latent tuberculosis despite negative test results. Through a careful review of posttransplant tuberculosis cases, we identify a history of treated tuberculosis in SOT recipients as a risk factor for development of posttransplant active tuberculosis. Finally, we include comparisons of recommendations by several large transplant organizations and identify areas for future research.

Infections in transplant patients

Recipients of solid organ transplants (SOT) need primary care providers (PCPs) who are familiar with their unique needs and understand the lifelong infectious risks faced by SOT patients because of their need for lifelong immunosuppressive medications. SOT recipients can present with atypical and muted manifestations of infections, for which the knowledgable PCP will initiate a comprehensive evaluation. The goal of this article is to familiarize PCPs with the infectious challenges facing SOT patients. General concepts are reviewed, and a series of patient cases described that illustrate the specific learning points based on common presenting clinical symptoms.

Varicella zoster virus (VZV) and herpes simplex virus (HSV) in solid organ transplant patients

Varicella zoster virus (VZV) and the two herpes simplex viruses (HSV) are human α-herpesviruses that establish life-long latency in neural ganglia after initial primary infection. In the solid organ transplant (SOT) population, manifestations of VZV or HSV may be seen in up to 70% of recipients if no prophylaxis is used, some of them life and organ threatening. While there are effective vaccines to prevent VZV primary infection and reactivation in immunocompetent adults, these vaccines are contraindicated after SOT because they are live-virus vaccines. For HSV, prevention has focused primarily on antiviral strategies because the immunologic correlates of protection and control are different from VZV, making vaccine development more challenging. Current antiviral therapy remains effective for the majority of clinical VZV and HSV infections.

Abrupt emergence of a single dominant multidrug-resistant strain of Escherichia coli

BACKGROUND

Fluoroquinolone-resistant Escherichia coli are increasingly prevalent. Their clonal origins--potentially critical for control efforts--remain undefined.

METHODS

Antimicrobial resistance profiles and fine clonal structure were determined for 236 diverse-source historical (1967-2009) E. coli isolates representing sequence type ST131 and 853 recent (2010-2011) consecutive E. coli isolates from 5 clinical laboratories in Seattle, Washington, and Minneapolis, Minnesota. Clonal structure was resolved based on fimH sequence (fimbrial adhesin gene: H subclone assignments), multilocus sequence typing, gyrA and parC sequence (fluoroquinolone resistance-determining loci), and pulsed-field gel electrophoresis.

RESULTS

Of the recent fluoroquinolone-resistant clinical isolates, 52% represented a single ST131 subclonal lineage, H30, which expanded abruptly after 2000. This subclone had a unique and conserved gyrA/parC allele combination, supporting its tight clonality. Unlike other ST131 subclones, H30 was significantly associated with fluoroquinolone resistance and was the most prevalent subclone among current E. coli clinical isolates, overall (10.4%) and within every resistance category (11%-52%).

CONCLUSIONS

Most current fluoroquinolone-resistant E. coli clinical isolates, and the largest share of multidrug-resistant isolates, represent a highly clonal subgroup that likely originated from a single rapidly expanded and disseminated ST131 strain. Focused attention to this strain will be required to control the fluoroquinolone and multidrug-resistant E. coli epidemic.

DAS181 treatment of severe parainfluenza type 3 pneumonia in a lung transplant recipient

Parainfluenza virus (PIV) may cause life‐threatening pneumonia in lung transplant patients and there are no proven effective therapies. We report the use of inhaled DAS181, a novel sialidase fusion protein, to treat severe PIV type 3 pneumonia in a lung transplant patient. Treatment was well tolerated and associated with improvement in oxygenation and symptoms, along with rapid clearance of PIV. DAS181 should be systematically evaluated for treatment of PIV infection in transplant recipients.

Efficacy and safety of maribavir dosed at 100 mg orally twice daily for the prevention of cytomegalovirus disease in liver transplant recipients: a randomized, double-blind, multicenter controlled trial

Maribavir is an oral benzimidazole riboside with potent in vitro activity against cytomegalovirus (CMV), including some CMV strains resistant to ganciclovir. In a randomized, double-blind, multicenter trial, the efficacy and safety of prophylactic oral maribavir (100 mg twice daily) for prevention of CMV disease were compared with oral ganciclovir (1000 mg three times daily) in 303 CMV-seronegative liver transplant recipients with CMV-seropositive donors (147 maribavir; 156 ganciclovir). Patients received study drug for up to 14 weeks and were monitored for CMV infection by blood surveillance tests and also for the development of CMV disease. The primary endpoint was Endpoint Committee (EC)-confirmed CMV disease within 6 months of transplantation. In a modified intent-to-treat analysis, the noninferiority of maribavir compared to oral ganciclovir for prevention of CMV disease was not established (12% with maribavir vs. 8% with ganciclovir: event rate difference of 0.041; 95% CI: -0.038, 0.119). Furthermore, significantly fewer ganciclovir patients had EC-confirmed CMV disease or CMV infection by pp65 antigenemia or CMV DNA PCR compared to maribavir patients at both 100 days (20% vs. 60%; p < 0.0001) and at 6 months (53% vs. 72%; p = 0.0053) after transplantation. Graft rejection, patient survival, and non-CMV infections were similar for maribavir and ganciclovir patients. Maribavir was well-tolerated and associated with fewer hematological adverse events than oral ganciclovir. At a dose of 100 mg twice daily, maribavir is safe but not adequate for prevention of CMV disease in liver transplant recipients at high risk for CMV disease.

Update and review: state-of-the-art management of cytomegalovirus infection and disease following thoracic organ transplantation

PURPOSE

Cytomegalovirus (CMV) is among the most important viral pathogens affecting solid organ recipients. The direct effects of CMV (eg, infection and its sequela; tissue invasive disease) are responsible for significant morbidity and mortality. In addition, CMV is associated with numerous indirect effects, including immunomodulatory effects, acute and chronic rejection, and opportunistic infections. Due to the potentially devastating effects of CMV, transplant surgeons and physicians have been challenged to fully understand this infectious complication and find the best ways to prevent and treat it to ensure optimal patient outcomes.

SUMMARY

Lung, heart, and heart-lung recipients are at considerably high risk of CMV infection. Both direct and indirect effects of CMV in these populations have potentially lethal consequences. The use of available treatment options depend on the level of risk of each patient population for CMV infection and disease. Those at the highest risk are CMV negative recipients of CMV positive organs (D+/R-), followed by D+/R+, and D-/R+. More than 1 guideline exists delineating prevention and treatment options for CMV, and new guidelines are being developed. It is hoped that new treatment algorithms will provide further guidance to the transplantation community. The first part describes the overall effects of CMV, both direct and indirect; risk factors for CMV infection and disease; methods of diagnosis; and currently available therapies for prevention and treatment. Part 2 similarly addresses antiviral-resistant CMV, summarizing incidence, risk factors, methods of diagnosis, and treatment options. Parts 3 and 4 present cases to illustrate issues surrounding CMV in heart and lung transplantation, respectively. Part 3 discusses the possible mechanisms by which CMV can cause damage to the coronary allograft and potential techniques of avoiding such damage, with emphasis on fostering strong CMV-specific immunity. Part 4 highlights the increased incidence of CMV infection and disease among lung transplant recipients and its detrimental effect on survival. The possible benefits of extended-duration anti-CMV prophylaxis are explored, as are those of combination prophylaxis with valganciclovir and CMVIG.

CONCLUSION

Through improved utilization of information regarding optimized antiviral therapy for heart and lung transplant recipients to prevent and treat CMV infection and disease and through increased understanding of clinical strategies to assess, treat, and monitor patients at high risk for CMV recurrence and resistance, the health care team will be able to provide the coordinated effort needed to improve patient outcomes.

Primary response against cytomegalovirus during antiviral prophylaxis with valganciclovir, in solid organ transplant recipients

Antiviral prophylaxis has proved successful for prevention of cytomegalovirus (CMV) disease in solid organ transplant (SOT) patients; though emerging data suggest that antiviral agents interfere with immunity, and may inhibit immune priming. In this context, we investigated levels and phenotype of primary CMV-specific immune responses that developed during antiviral prophylaxis in a cohort of CMV seronegative recipients (R(-) ) of a SOT from a seropositive donor (D(+) ). We longitudinally monitored CMV viral load, antibodies and levels of the negative immuno-modulator IL-10. PBMC were stimulated with CMV-specific peptide libraries to measure CD137 activation marker on CMV-specific T-cells and levels of PD-1 receptor, which is over expressed on exhausted T-cells. Unexpectedly, the majority (13/18) of D(+) R(-) patients who developed a primary CMV response showed early post-transplant CMV-specific responses, though levels of PD-1 on CMV-specific T-cells remained elevated throughout prophylaxis. A strong inverse association was found between levels of plasma IL-10 and CMV-specific cellular immune responses. Our study suggests that during prophylaxis, subclinical CMV infection might have occurred in the D(+) R(-) patients, and primary CMV-specific responses were detected early post-transplant when levels of plasma IL-10 were low. Extended prophylaxis or antiviral treatment did not appear to suppress CMV-specific antibodies or T-cells, which, however, showed exhaustion phenotypes.

Herpes zoster incidence in a multicenter cohort of solid organ transplant recipients

BACKGROUND

Immunosuppressed patients are at increased risk for herpes zoster (HZ), but incidence in solid organ transplant (SOT) recipients has varied in multiple studies. To assess incidence of HZ, we examined patients who underwent SOT and received follow-up care within the large multicenter US Department of Veteran's Affairs healthcare system.

METHODS

Incident cases of HZ were determined using ICD-9 coding from administrative databases. A multivariable Cox proportional hazards model, adjusted for a priori risk factors, was used to assess demographic factors associated with development of HZ.

RESULTS

Among the 1077 eligible SOT recipients, the cohort-specific incidence rate of HZ was 22.2 per 1000 patient-years (95% confidence interval [CI], 18.1-27.4). African Americans (37.6 per 1000 [95% CI, 25.0-56.6]) and heart transplants recipients (40.0 per 1000 [95% CI, 23.2-68.9]) had the highest incidence of HZ. Patients transplanted between 2005 and 2007 had the lowest incidence (15.3 per 1000 [95% CI, 8.2-28.3]). In a multivariable model, African Americans (hazard ratio [HR] 1.88; 95% CI: 1.12, 3.17) and older transplant recipients (HR 1.13; 95% CI: 1.01, 1.27 [per 5-year increment]) had increased relative hazards of HZ.

CONCLUSIONS

These data demonstrate that HZ is a common infectious complication following SOT. Future studies focused on HZ prevention are needed in this high-risk population.

Risk factors for late-onset cytomegalovirus disease in donor seropositive/recipient seronegative kidney transplant recipients who receive antiviral prophylaxis

BACKGROUND

Cytomegalovirus (CMV) disease occurs frequently after cessation of antiviral prophylaxis in CMV-seronegative kidney transplant recipients from seropositive donors (D+R-), and the risk factors are incompletely defined.

METHOD

We retrospectively assessed the incidence, clinical features, and risk factors for CMV disease in a cohort of D+R- kidney transplant recipients who received antiviral prophylaxis at a single US transplant center using descriptive statistics and Cox proportional hazards models.

RESULTS

CMV disease developed in 29 of 113 (26%) D+R- patients at a median of 185 days (interquartile range 116-231 days) post transplant, including CMV syndrome (66%) and tissue invasive disease (34%). The incidence of CMV disease was higher in patients who underwent re-transplantation (57% vs. 24%) and this factor was independently associated with a higher risk of CMV disease in multivariable analysis (hazard ratio, 4.02; 95% confidence interval, 1.3-13; P = 0.016). Other demographic and transplant variables were not independently associated with a risk of late-onset CMV disease.

CONCLUSIONS

Despite a comprehensive analysis of patient and transplant variables, only re-transplantation was identified as a risk factor for CMV disease in D+R- kidney transplant recipients who received antiviral prophylaxis, but had limited clinical predictive value. The development of novel laboratory markers to identify patients at greatest risk for CMV disease should be a priority for future studies.

Unrecognized pretransplant and donor‐derived cryptococcal disease in organ transplant recipients

BACKGROUND

Cryptococcosis occurring ≤30 days after transplantation is an unusual event, and its characteristics are not known.

METHODS

Patients included 175 solid-organ transplant (SOT) recipients with cryptococcosis in a multicenter cohort. Very early-onset and late-onset cryptococcosis were defined as disease occurring ≤30 days or >30 days after transplantation, respectively.

RESULTS

Very early-onset disease developed in 9 (5%) of the 175 patients at a mean of 5.7 days after transplantation. Overall, 55.6% (5 of 9) of the patients with very early-onset disease versus 25.9% (43 of 166) of the patients with late-onset disease were liver transplant recipients (P = .05). Very early cases were more likely to present with disease at unusual locations, including transplanted allograft and surgical fossa/site infections (55.6% vs 7.2%; P < .001). Two very early cases with onset on day 1 after transplantation (in a liver transplant recipient with Cryptococcus isolated from the lung and a heart transplant recipient with fungemia) likely were the result of undetected pretransplant disease. An additional 5 cases involving the allograft or surgical sites were likely the result of donor&#x2010;acquired infection.

CONCLUSIONS

A subset of SOT recipients with cryptococcosis present very early after transplantation with disease that appears to occur preferentially in liver transplant recipients and involves unusual sites, such as the transplanted organ or the surgical site. These patients may have unrecognized pretransplant or donor-derived cryptococcosis.

Cutaneous cryptococcosis in solid organ transplant recipients

Clinical manifestations, treatment, and outcomes of cutaneous cryptococcosis in solid organ transplant (SOT) recipients are not fully defined. In a prospective cohort comprising 146 SOT recipients with cryptococcosis, we describe the presentation, antifungal therapy, and outcome of cutaneous cryptococcal disease. Cutaneous cryptococcosis was documented in 26/146 (17.8%) of the patients and manifested as nodular/mass (34.8%), maculopapule (30.4%), ulcer/pustule/abscess (30.4%), and cellulitis (30.4%) with 65.2% of the skin lesions occurred in the lower extremities. Localized disease developed in 30.8% (8/26), and disseminated disease in 69.2% (18/26) with involvement of the central nervous system (88.9%, 16/18), lung (33.3%, 6/18), or fungemia (55.6%, 10/18). Fluconazole (37.5%) was employed most often for localized and lipid formulations of amphotericin B (61.1%) for disseminated disease. Overall mortality at 90 days was 15.4% (4/26) with 16.7% in disseminated and 12.5% in localized disease (P = 0.78). SOT recipients who died were more likely to have renal failure (75.0% vs. 13.6%, P = 0.028), longer time to onset of disease after transplantation (87.5 vs. 22.6 months, P = 0.023), and abnormal mental status (75% vs. 13.6%, P = 0.028) than those who survived. Cutaneous cryptococcosis represents disseminated disease in most SOT recipients and preferentially involves the extremities. Outcomes with appropriate management were comparable between SOT recipients with localized and disseminated cryptococcosis.

CMV in critically ill patients: pathogen or bystander?

Despite broad variability in study populations, methodologies for CMV detection, and analytic methods used, multiple studies have documented frequent CMV infection in non-immunocompromised adults with critical illness due to a variety of causes. Higher rates of CMV infection in studies of seropositive patients suggest that reactivation of latent infection rather than primary infection is the main mechanism in this setting. Risk factors for CMV reactivation (other than seropositivity) have not been clearly defined and there does not appear to be a consistent association with severity of illness. Furthermore, CMV reactivation in this setting has been associated with important adverse clinical outcomes, including increased duration of mechanical ventilation, longer length of stay and all-cause mortality. There are several biologically plausible mechanisms that could link CMV reactivation with adverse outcomes, including: direct lung injury (CMV pneumonia), amplification of inflammation systemically and within the lung, or predisposition to other nosocomial infections, but clinical data in the ICU setting are limited. Further observational studies are unlikely to significantly advance our understanding of the role of CMV in critically ill patients. Given the significant impact of critical illness, limited current therapeutic options, the availability of generally well-tolerated antiviral options for CMV, and the clinical data supporting a possible pathogenic role for CMV, there is a strong rationale for a randomised controlled trial of CMV prevention as a novel means of improving the outcomes of critically ill patients.

Geographic differences in disease expression of cryptococcosis in solid organ transplant recipients in the United States

BACKGROUND

Whether there are geographic differences in clinical presentation of cryptococcosis in solid organ transplant (SOT) recipients in the United States (US) is not known.

MATERIAL/METHODS

Patients comprised a cohort of 120 SOT recipients from US transplant centers who fulfilled the EORTC/MSG criteria for cryptococcal disease.

RESULTS

Central nervous system, pulmonary, and cutaneous cryptococcal disease were observed in 51% (61/120), 64% (77/120), and 15% (18/120) of the patients, respectively. Cutaneous disease was documented in 9% (3/32) of the patients from South Atlantic region, 19% (6/32) from Mid Atlantic, 26% (6/23) from Southern, 7% (2/29) from Midwestern, and in 1 of 4 patients from the Northwestern region of the US. When controlled for age, immunosuppressive regimen, type of transplant, and renal failure at baseline, patients from the Southern compared with other regions of the US were significantly more likely to have cutaneous cryptococcal disease (OR 3.8, 95% CI 1.1-14, P=0.045).

CONCLUSIONS

Post-transplant cryptococcosis is more likely to present with cutaneous disease in the Southern region compared with other regions in the US. This predilection for cutaneous cryptococcosis could not be explained on the basis of differences in immunosuppression or the type of transplant. Whether our findings are related to strain-related variations in characteristics of the yeast or other transplant variables remains to be determined.

Surface plasmon resonance detection using antibody-linked magnetic nanoparticles for analyte capture, purification, concentration, and signal amplification

Rapid, sensitive, and accurate detection of analytes present in low concentrations in complex matrixes is a critical challenge. One issue that affects many biosensor protocols is the number and nature of the interferences present in complex matrixes such as plasma, urine, stool, and environmental samples, resulting in loss of sensitivity and specificity. We have developed a method for rapid purification, concentration, and detection of target analytes from complex matrixes using antibody-coated superparamagnetic nanobeads (immunomagnetic beads, or IMBs). The surface plasmon resonance (SPR) detection signal from staphylococcal enterotoxin B (SEB) was dramatically increased when the IMBs were used as detection amplifiers. When SEB detection included a 10-fold concentration/purification IMB protocol, a substantial increase in detection sensitivity was observed. This procedure was used to successfully purify and concentrate SEB from serum and stool samples, then amplify the SPR detection signal. SEB at a concentration of 100 pg/mL was easily detected in both buffer and stool samples using this procedure. The IMB protocol also served to verify the analyte detection by using two different anti-SEB antibodies, mouse monoclonal antibodies attached to the magnetic nanobeads and rabbit polyclonal antibodies on the SPR sensor surface. Multiple detections of SEB in stool were performed using the same sensor surface by regenerating the sensor surfaces with a pH 2.2 buffer wash.

Extended valganciclovir prophylaxis to prevent cytomegalovirus after lung transplantation: a randomized, controlled trial

BACKGROUND

Cytomegalovirus (CMV) is the most prevalent opportunistic infection after lung transplantation. Current strategies do not prevent CMV in most at-risk patients.

OBJECTIVE

To determine whether extending prophylaxis with oral valganciclovir from the standard 3 months to 12 months after lung transplantation is efficacious.

DESIGN

Randomized, clinical trial. Patients were randomly assigned by a central automated system to treatment or placebo. Patients and investigators were blinded to treatment status. (ClinicalTrials.gov registration number: NCT00227370)

SETTING

Multicenter trial involving 11 U.S. lung transplant centers.

PATIENTS

136 lung transplant recipients who completed 3 months of valganciclovir prophylaxis.

INTERVENTION

9 additional months of oral valganciclovir (n = 70) or placebo (n = 66).

MEASUREMENTS

The primary end point was freedom from CMV disease (syndrome or tissue-invasive) on an intention-to-treat basis 300 days after randomization. Secondary end points were CMV disease severity, CMV infection, acute rejection, opportunistic infections, ganciclovir resistance, and safety.

RESULTS

CMV disease occurred in 32% of the short-course group versus 4% of the extended-course group (P < 0.001). Significant reductions were observed with CMV infection (64% vs. 10%; P < 0.001) and disease severity (110 000 vs. 3200 copies/mL, P = 0.009) with extended treatment. Rates of acute rejection, opportunistic infections, adverse events, CMV UL97 ganciclovir-resistance mutations, and laboratory abnormalities were similar between groups. During the 6 months after study completion, a low incidence of CMV disease was observed in both groups.

LIMITATION

Longer-term effects of extended prophylaxis were not assessed.

CONCLUSION

In adult lung transplant recipients who have received 3 months of valganciclovir, extending prophylaxis by an additional 9 months significantly reduces CMV infection, disease, and disease severity without increased ganciclovir resistance or toxicity. A beneficial effect with regard to prevention of CMV disease seems to extend at least through 18 months after transplantation.

The efficacy and safety of 200 days valganciclovir cytomegalovirus prophylaxis in high-risk kidney transplant recipients

Late-onset cytomegalovirus (CMV) disease is a significant problem with a standard 3-month prophylaxis regimen. This multicentre, double-blind, randomized controlled trial compared the efficacy and safety of 200 days' versus 100 days' valganciclovir prophylaxis (900 mg once daily) in 326 high-risk (D+/R-) kidney allograft recipients. Significantly fewer patients in the 200-day group versus the 100-day group developed confirmed CMV disease up to month 12 posttransplant (16.1% vs. 36.8%; p < 0.0001). Confirmed CMV viremia was also significantly lower in the 200-day group (37.4% vs. 50.9%; p = 0.015 at month 12). There was no significant difference in the rate of biopsy-proven acute rejection between the groups (11% vs. 17%, respectively, p = 0.114). Adverse events occurred at similar rates between the groups and the majority were rated mild-to-moderate in intensity and not related to study medication. In conclusion, this study demonstrates that extending valganciclovir prophylaxis (900 mg once daily) to 200 days significantly reduces the incidence of CMV disease and viremia through to 12 months compared with 100 days' prophylaxis, without significant additional safety concerns associated with longer treatment. The number needed to treat to avoid one additional patient with CMV disease up to 12 months posttransplant is approximately 5.

Lipid formulations of amphotericin B significantly improve outcome in solid organ transplant recipients with central nervous system cryptococcosis

BACKGROUND

Whether outcome of central nervous system (CNS) cryptococcosis in solid organ transplant recipients treated with lipid formulations of amphotericin B is different from the outcome of the condition treated with amphotericin B deoxycholate (AmBd) is not known.

METHODS

We performed a multicenter study involving a cohort comprising consecutive solid organ transplant recipients with CNS cryptococcosis.

RESULTS

Of 75 patients treated with polyenes as induction regimens, 55 (73.3%) received lipid formulations of amphotericin B and 20 (26.7%) received AmBd. Similar proportions of patients in both groups had renal failure at baseline (P = .94 ). Overall, mortality at 90 days was 10.9% in the group that received lipid formulations of amphotericin B and 40.0% in the group that received AmBd. In univariate analysis, nonreceipt of calcineurin inhibitors (P = .034), renal failure at baseline (P = .016), and fungemia (P = .003) were significantly associated with mortality. Compared with AmBd, lipid formulations of amphotericin B were associated with a lower mortality (P = .007). Mortality did not differ between patients receiving lipid formulations of amphotericin B with or without flucytosine (P = .349). In stepwise logistic regression analysis, renal failure at baseline (odds ratio [OR], 4.61; 95% confidence interval [CI], 1.02-20.80; P = .047) and fungemia (OR, 10.66; 95% CI, 2.08-54.55; P = .004 ) were associated with an increased mortality, whereas lipid formulations of amphotericin B were associated with a lower mortality (OR, 0.11; 95% CI, 0.02-0.57; P = .008).

CONCLUSIONS

Lipid formulations of amphotericin B were independently associated with better outcome and may be considered as the first-line treatment for CNS cryptococcosis in these patients.

Programmed death-1 receptor and interleukin-10 in liver transplant recipients at high risk for late cytomegalovirus disease

Despite significant advances in antiviral treatment, solid organ transplant (SOT) recipients remain at heightened risk for developing late cytomegalovirus (CMV) disease. Elevated inhibitory immune signaling suggests a state of immune impairment in SOT recipients, who do not control CMV infection and develop severe clinical symptoms after discontinuation of antiviral prophylaxis. We longitudinally monitored the negative immune modulator programmed death (PD)-1 receptor on both CD4 and CD8 T cells, co-expressing the CD137 surface marker of recent activation, in a liver transplant cohort. Liver recipients who progressed to CMV disease expressed elevated levels of PD-1 on CD137(+) CD4 and CD8 T cells, following stimulation with either full-length peptide libraries or CMV lysate. This novel approach, applicable to a multitude of human leukocyte antigen types, enhances the usefulness of the PD-1 measurements as a clinical strategy to predict late CMV disease. In parallel, we detected an increased level of the immunosuppressive cytokine interleukin (IL)-10, in plasma of liver recipients diagnosed with CMV disease. CMV-specific T cells were still functional when both PD-1 and IL-10 were upregulated; however they showed a marked proliferation deficit, which may limit their ability to contain viremia and lead to CMV disease. Our preliminary observations support further investigation of dual monitoring of PD-1 and IL-10, as potential immune markers of CMV disease.

Strongyloidiasis in transplant patients

Strongyloides stercoralis is an intestinal nematode that can persist in the human host for decades after the initial infection and can progress to fulminant hyperinfection syndrome in immunocompromised hosts. We describe a patient who died of Strongyloides hyperinfection syndrome 2 months after orthotopic heart transplantation and discuss approaches to prevention, diagnosis, and treatment. Current practice guidelines recommend screening for and treatment of Strongyloides infection before transplantation, but physicians in the United States often miss opportunities to identify patients with chronic strongyloidiasis. Screening tests have limitations, and clinical suspicion remains an important component of the evaluation before transplantation. After immunocompromised patients develop hyperinfection syndrome, diagnosis is often delayed and mortality is high, so emphasis must be placed on screening and treatment before transplantation. We review current strategies for prevention, diagnosis, and treatment of chronic intestinal strongyloidiasis in patients who will undergo transplantation and discuss the clinical features and management of Strongyloides hyperinfection syndrome in transplant recipients.

Systematic assessment of culture review as a tool to assess errors in the clinical microbiology laboratory

CONTEXT

Daily supervisory review is a common practice in microbiology laboratories; however, there are no publications describing errors corrected by this practice.

OBJECTIVE

To determine (1) the correction rates for routinely reviewed positive cultures, (2) the correction rates for negative cultures, and (3) the types of corrections that are found, including the number with potential clinical significance.

DESIGN

We prospectively assessed errors identified during culture report review for all positive (10-month period) and negative (1-month period) cultures at a single, university-based clinical microbiology laboratory in the United States. Errors were classified using predefined categories, and total and per category error rates were determined. A chi(2) test was used to assess significant differences between error rates.

RESULTS

A total of 112,108 culture reports were examined; 914 reports required a total of 1043 corrections. Of 101,703 positive culture reports, 786 (0.8%) required 900 corrections, 302 (0.3%) of which were potentially clinically significant. Of 10,405 negative culture reports, 128 (1.2%) required 143 corrections, 5 (0.05%) of which were potentially clinically significant. The rate of potentially clinically significant errors was significantly higher among positive versus negative culture reports (P < .001). Errors from positive culture reports most commonly involved susceptibility (374 [42%]), reporting (275 [31%]), and identification workup (217 [24%]). Most potentially significant errors from positive culture reports involved susceptibility testing (n = 253) and specimens from wound or lower respiratory tract (P < .001).

CONCLUSIONS

Review of culture reports from positive cultures from nonsterile sites with special attention to antimicrobial susceptibility testing and reporting would be most likely to detect potentially significant errors within the clinical microbiology laboratory.

Cytomegalovirus reactivation in critically ill immunocompetent patients

CONTEXT

Cytomegalovirus (CMV) infection is associated with adverse clinical outcomes in immunosuppressed persons, but the incidence and association of CMV reactivation with adverse outcomes in critically ill persons lacking evidence of immunosuppression have not been well defined.

OBJECTIVE

To determine the association of CMV reactivation with intensive care unit (ICU) and hospital length of stay in critically ill immunocompetent persons.

DESIGN, SETTING, AND PARTICIPANTS

We prospectively assessed CMV plasma DNAemia by thrice-weekly real-time polymerase chain reaction (PCR) and clinical outcomes in a cohort of 120 CMV-seropositive, immunocompetent adults admitted to 1 of 6 ICUs at 2 separate hospitals at a large US tertiary care academic medical center between 2004 and 2006. Clinical measurements were assessed by personnel blinded to CMV PCR results. Risk factors for CMV reactivation and association with hospital and ICU length of stay were assessed by multivariable logistic regression and proportional odds models.

MAIN OUTCOME MEASURES

Association of CMV reactivation with prolonged hospital length of stay or death.

RESULTS

The primary composite end point of continued hospitalization (n = 35) or death (n = 10) by 30 days occurred in 45 (35%) of the 120 patients. Cytomegalovirus viremia at any level occurred in 33% (39/120; 95% confidence interval [CI], 24%-41%) at a median of 12 days (range, 3-57 days) and CMV viremia greater than 1000 copies/mL occurred in 20% (24/120; 95% CI, 13%-28%) at a median of 26 days (range, 9-56 days). By logistic regression, CMV infection at any level (adjusted odds ratio [OR], 4.3; 95% CI, 1.6-11.9; P = .005) and at greater than 1000 copies/mL (adjusted OR, 13.9; 95% CI, 3.2-60; P < .001) and the average CMV area under the curve (AUC) in log(10) copies per milliliter (adjusted OR, 2.1; 95% CI, 1.3-3.2; P < .001) were independently associated with hospitalization or death by 30 days. In multivariable partial proportional odds models, both CMV 7-day moving average (OR, 5.1; 95% CI, 2.9-9.1; P < .001) and CMV AUC (OR, 3.2; 95% CI, 2.1-4.7; P < .001) were independently associated with a hospital length of stay of at least 14 days.

CONCLUSIONS

These preliminary findings suggest that reactivation of CMV occurs frequently in critically ill immunocompetent patients and is associated with prolonged hospitalization or death. A controlled trial of CMV prophylaxis in this setting is warranted.

Programmed death-1 expression in liver transplant recipients as a prognostic indicator of cytomegalovirus disease

Immunological parameters that distinguish solid-organ transplant (SOT) recipients at risk for life-threatening cytomegalovirus (CMV) disease are being actively pursued to aid posttransplant management. A candidate marker is programmed death (PD)-1 receptor, whose overexpression has been associated with disease progression during persistent viral infections. To determine whether levels of this negative regulator of T cell activity are altered in SOT recipients with symptoms of CMV disease, a comparative PD-1 expression analysis was done in healthy, CMV-positive individuals and in liver transplant recipients. PD-1 levels were measured among the total population of CD8(+) and CD8(+) T cells binding to CMV-specific major histocompatibility complex class I tetramers. Minimal PD-1 expression was found in the healthy, CMV-positive cohort, and symptomatic SOT recipients had significantly higher PD-1 levels. PD-1 up-regulation was significantly associated with incipient and overt CMV disease and with viremia. Our findings suggest that PD-1 could be developed as a prognostic tool to predict CMV disease and guide therapeutic interventions.

Pulmonary cryptococcosis in solid organ transplant recipients: clinical relevance of serum cryptococcal antigen

BACKGROUND

The role of serum cryptococcal antigen in the diagnosis and determinants of antigen positivity in solid organ transplant (SOT) recipients with pulmonary cryptococcosis has not been fully defined.

METHODS

We conducted a prospective, multicenter study of SOT recipients with pulmonary cryptococcosis during 1999-2006.

RESULTS

Forty (83%) of 48 patients with pulmonary cryptococcosis tested positive for cryptococcal antigen. Patients with concomitant extrapulmonary disease were more likely to have a positive antigen test result (P=.018), and antigen titers were higher in patients with extrapulmonary disease (P=.003) or fungemia (P=.045). Patients with single nodules were less likely to have a positive antigen test result than were those with all other radiographic presentations (P=.053). Among patients with isolated pulmonary cryptococcosis, lung transplant recipients were less likely to have positive cryptococcal antigen test results than were recipients of other types of SOT (P=.003). In all, 38% of the patients were asymptomatic or had pulmonary cryptococcosis detected as an incidental finding. Nodular densities or mass lesions were more likely to present as asymptomatic or incidentally detected pulmonary cryptococcosis than as pleural effusions and infiltrates (P=.008).

CONCLUSIONS

A positive serum cryptococcal antigen test result in SOT recipients with pulmonary cryptococcosis appears to reflect extrapulmonary or more advanced radiographic disease.

Serologic evidence for reactivation of cryptococcosis in solid-organ transplant recipients

Cryptococcosis is a significant infection with a high mortality in solid-organ transplant recipients. Nonetheless, the pathogenesis of this disease is poorly understood. It has been hypothesized that cryptococcosis may result from either primary infection or reactivation of a latent infection. Sera were obtained from transplant recipients prior to transplantation and at the time they developed cryptococcosis. Control sera were obtained before and after transplant from patients who did not develop cryptococcosis. Sera were tested for antibodies against Cryptococcus neoformans by using an immunoblot assay. Antibody responses were also compared with those observed in sera from rats with experimental pulmonary cryptococcosis. In all, 52% of the transplant recipients who developed cryptococcosis exhibited serologic evidence of cryptococcal infection before transplantation. These patients developed cryptococcosis significantly earlier after transplant than patients without preexisting reactivity did (5.6 +/- 3.4 months compared to 40.6 +/- 63.8 months, respectively [P = 0.0011]). The results from our study suggest that a substantial proportion of transplant-associated cryptococcosis cases result from the reactivation of a latent infection. These findings also highlight the potential utility of serologic studies in identifying patients at risk for the development of cryptococcosis after transplantation.

In vitro activity of fluoroquinolones against clinical isolates of Nocardia identified by partial 16S rRNA sequencing

Fluoroquinolones have several properties that make them potentially attractive candidates for the treatment of Nocardia infections, but information regarding their in vitro activity is limited. Minimum inhibitory concentrations (MIC) of five fluoroquinolones and other antimicrobials were determined by the reference broth dilution and E-test methods for 33 consecutive clinical isolates of Nocardia speciated by 16S rRNA gene sequences. The isolates included: Nocardia cyriacigeorgica (n = 6), N. nova (n = 8), N. farcinica (n = 8), N. brasiliensis (n = 3), N. asteroides (n = 4), and N. veterana (n = 4). MIC50/MIC90 results for ciprofloxacin, gatifloxacin, gemifloxacin, levofloxacin, and moxifloxacin by broth dilution were 32/32, 2/4, 1/4, 32/32, and 2/2 microg/ml, respectively. The MICs by broth dilution and E-test were within a two-fold doubling dilution for 94%, 97%, 97%, 100%, and 100% of isolates for ciprofloxacin, gatifloxacin, gemifloxacin, levofloxacin, and moxifloxacin, respectively. For ciprofloxacin, the E-test results showed either complete categorical agreement or minor error compared to the reference broth dilution method for 97% (32/33) of the isolates. For other fluoroquinolones, using Streptococcus pneumoniae breakpoints, 94% (124/132) of MIC results by E-test showed either complete agreement or minor error compared to the reference broth dilution method. Fluoroquinolones show variable in vitro activity against clinical isolates of Nocardia spp., and MICs determined by the E-test show reasonable agreement with those determined by the reference broth dilution method.

Incidence and Clinical Features of Ganciclovir- Resistant Cytomegalovirus Disease in Heart Transplant Recipients

BACKGROUND

The incidence and clinical and virologic aspects of ganciclovir-resistant cytomegalovirus (CMV) disease have not been well-characterized in heart transplant recipients.

METHODS

We retrospectively analyzed all patients who underwent their first heart transplantation during the period from 1 January 1995 through 30 June 2005 at a single health care center. Cox proportional hazard regression was used to assess the relationship between clinical variables and CMV disease. Portions of the UL97 gene were sequenced in patients with slow clinical and/or virologic response to ganciclovir therapy.

RESULTS

Cytomegalovirus disease developed in 32 (11.7%) of 274 patients at a median of 4.2 months after transplantation (range, 1.8-11.6 months after transplantation) and was independently associated with donor-seropositive/recipient-seronegative (D+/R-) serostatus (adjusted hazard ratio, 6.93; P<.001). The incidence of ganciclovir-resistant CMV disease was 1.5% overall (4 of 274 patients), 5% among D+/R- serostatus recipients (4 of 80 patients), and 12.5% among patients who developed CMV disease (4 of 32 patients). Ganciclovir-resistant CMV disease was significantly associated with D+/R- serostatus (4 [5%] of 80 vs. 0 [0%] of 153 patients; P=.02), greater prior exposure to ganciclovir (median duration of exposure, 150 vs. 69 days; P=.003), and substantial morbidity, including prolonged CMV-associated hospitalization (median duration of hospitalization, 66 vs. 0 days; P<.01).

CONCLUSIONS

CMV disease, including ganciclovir-resistant disease, is an important clinical problem in D+/R- heart transplant recipients who receive antiviral prophylaxis. Strategies specifically designed to reduce the incidence and impact of CMV disease in this population are warranted.

Invasive Pseudomonas aeruginosa infections: high rate of recurrence and mortality after hematopoietic cell transplantation

Limited data exist regarding the incidence and factors associated with outcome of invasive Pseudomonal infections in hematopoietic cell transplant (HCT). A retrospective analysis of cases of invasive Pseudomonas aeruginosa infection and factors associated with outcome was performed. P. aeruginosa invasive infection occurred in 95 of 5772 patients (1.65%) a median of 63 days after HCT (range 5-1435). Only 28% of infections occurred during periods of neutropenia (absolute neutrophil count<500 cells/mm(3)). Infection-attributable mortality during the initial episode of infection was 35.8%. Factors associated with initial mortality included the presence of a copathogen and high-dose steroid use. Ten (16.4%) of those who survived the initial infection experienced a recurrence of P. aeruginosa infection at a median of 9 days (range 3-17) after stopping antibiotics and 60% of those died as a result of recurrent infection a median of 1 day (range 1-7) after onset of recurrence. Grade 3-4 graft-versus-host disease was associated with a higher risk of recurrent infection. The risk of recurrence was not influenced by the presence of copathogens. Thus, invasive P. aeruginosa infections are associated with high recurrence rates and mortality in this immunocompromised population. Aggressive attempts to reduce immunosuppression and to treat copathogens may help during the initial infection.

Longitudinal Assessment of Cytomegalovirus (CMV)–Specific Immune Responses in Liver Transplant Recipients at High Risk for Late CMV Disease

Cytomegalovirus (CMV)-seronegative recipients (R(-)) of a liver transplant from CMV-positive donors (D(+)) are at high risk for developing late CMV disease after discontinuation of antiviral prophylaxis. Levels of viremia and CMV-specific interferon (IFN)- gamma -producing CD4(+) and IFN- gamma -producing CD8(+) T cell responses were prospectively measured from discontinuation of antiviral prophylaxis until 1 year after transplantation in 17 consecutive D(+)/R(-) patients. CMV loads of >1000 copies/mL were strongly associated with CMV disease in the 6 symptomatic patients. Despite immunosuppression, broadly diverse T cells specific for CMV lysate or peptide libraries spanning pp65 and immediate early (IE) 1 immunodominant CMV antigens developed in all patients. A vigorous CD8(+) T cell response to pp65 and IE1 antigens characterized the D(+)/R(-) cohort. Unexpectedly, none of these responses were predictive of CMV disease or viremia. No significant lymphopenia or functional impairment of CMV-specific T cells was detected in the symptomatic patients, whose morbidity was resolved after antiviral treatment while measurable CMV immunity was maintained during the 1-year observation period.

Cryptococcus neoformans in organ transplant recipients: impact of calcineurin-inhibitor agents on mortality

Variables influencing the risk of dissemination and outcome of Cryptococcus neoformans infection were assessed in 111 organ transplant recipients with cryptococcosis in a prospective, multicenter, international study. Sixty-one percent (68/111) of the patients had disseminated infection. The risk of disseminated cryptococcosis was significantly higher for liver transplant recipients (adjusted hazard ratio [HR], 6.65; P=.048). The overall mortality rate at 90 days was 14% (16/111). The mortality rate was higher in patients with abnormal mental status (P=.023), renal failure at baseline (P=.028), fungemia (P=.006), and disseminated infection (P=.035) and was lower in those receiving a calcineurin-inhibitor agent (P=.003). In a multivariable analysis, the receipt of a calcineurin-inhibitor agent was independently associated with a lower mortality (adjusted HR, 0.21; P=.008), and renal failure at baseline with a higher mortality rate (adjusted HR, 3.14; P=.037). Thus, outcome in transplant recipients with cryptococcosis appears to be influenced by the type of immunosuppressive agent employed. Additionally, discerning the basis for transplant type-specific differences in disease severity has implications relevant for yielding further insights into the pathogenesis of C. neoformans infection in transplant recipients.

Association of hepatic iron overload with invasive fungal infection in liver transplant recipients

Invasive fungal infection is a serious complication of orthotopic liver transplantation, but its risk factors remain incompletely defined. Iron overload has already been associated with increased risk of fungal infections, but it has not yet been assessed as a risk factor in liver transplantation. We retrospectively studied a cohort of 153 consecutive patients who underwent their first liver transplantation at a single center and who survived at least 7 days after transplantation. The association between various pretransplant patient characteristics, including hepatic explant iron and risk of invasive fungal infections, was analyzed by univariate and multivariate models. Iron in the hepatic explant was assessed by Perl's Prussian blue stain by a pathologist blinded to clinical outcome. During the first year after transplantation, 28 of 153 patients developed a total of 31 invasive fungal infections, of which 21 (68%) were caused by Candida, 7 (23%) by Aspergillus, 2 (6%) by Cryptococcus, and 1 (3%) by Saccharomyces. Stainable iron in the hepatic explant was found in 48 patients (31%). Stainable iron in the hepatic explant was found to be strongly and independently associated with posttransplantation fungal infections in multivariate analysis (hazard ratio 3.09; 95% confidence interval 1.45-6.56; P = 0.003). Hepatic iron overload is strongly and independently associated with posttransplantation invasive fungal infections. Studies to confirm this finding in other centers and define the mechanism are warranted.

Clinical and radiologic factors associated with pulmonary nodule etiology in organ transplant recipients

Identifying clinical and radiographic factors that are associated with a specific etiology of pulmonary nodules (PNs) in solid-organ transplant (SOT) recipients might be helpful in guiding empiric therapy. Multivariable logistic regression was used to assess the relationship of clinical and radiographic variables to the etiology of PN in a retrospectively identified cohort of SOT recipients at a single transplant center. PNs in 55 SOT recipients (lung 15%, heart 22%, liver 42%, kidney 18% or kidney/pancreas 5%) were diagnosed at a mean of 1061 days post-transplant and were infectious in 31 of 55 (56%) (bacterial 22%, fungal 33%, viral 2%) and noninfectious in 24 of 55 (44%) [post-transplant lymphoproliferative disorder (PTLD) 25%, carcinoma 18%]. Radiographic 'consolidation' was independently associated with an infectious etiology (OR, 20.2, p < 0.01). Epstein-Barr virus seronegativity and lung transplant were each associated with PTLD (OR, 21.7, p < 0.01) and (OR, 36.6, p < 0.001), respectively. Diagnosis less than 90 days post-transplant was associated with Aspergillus infection (OR, 12.9, p = 0.007). Specific clinical and radiographic features are associated with specific etiologies of PNs in SOT recipients and might be useful for guiding empiric therapy while awaiting results of definitive diagnostic studies.

Confirmation of Chagas' cardiomyopathy following heart transplantation

We report a case of Chagas' cardiomyopathy confirmed in a patient after heart transplantation. The patient initially presented with symptoms of congestive heart failure and was found to have positive serology for prior Trypanosoma cruzi infection. Despite optimal medical management, the patient had deterioration of his cardiac function and he underwent heart transplantation. Pathology examination of the explanted heart confirmed Chagas' cardiomyopathy. The cardiac sequelae of Chagas' disease include arrhythmias, aneurysm, thromboembolism, cardiomyopathy, and sudden death. We review the epidemiology, cardiac pathology, and evaluation of patients with Chagas' cardiac disease. We discuss the clinical features of Chagas' cardiomyopathy and available treatments including cardiac transplantation.

Systemic and cerebrospinal fluid T-helper cytokine responses in organ transplant recipients with Cryptococcus neoformans infection

BACKGROUND

The role of Th1 and Th2 mediated cytokine responses in the pathogenesis of Cryptococcus neoformans infection in organ transplant recipients has not been defined.

METHODS

We assessed cytokine levels in the sera and CSF collected prospectively at the time of diagnosis of infection in 25 transplant recipients with cryptococcosis. Serum levels were compared with those in healthy individuals and transplant recipients without cryptococcosis. IFN-gamma or IL-12 (Th1)/IL-10 (Th2) ratio < 1.0 was considered a dominant Th2 response.

RESULTS

Cases had lower ratios of IFN-gamma/IL-10 (p = 0.03) and IL-12/IL-10 (p = 0.03) compared to healthy individuals. Cytokine responses, however, did not differ significantly for cases vs. transplant controls. Cases with fungemia compared to those without fungemia tended to have higher serum IL-10 levels (p = 0.07) and lower IL-12/IL-10 ratios (p = 0.06). CSF ratios of IFN-gamma/IL-10 (p = 0.04) and IL-12/IL-10 (p = 0.04) were lower in cases with cryptococcal meningitis compared to those without meningitis; 80% (8/10) of the cases with cryptococcal meningitis vs. 0% (4/4) of those without meningitis had CSF IFN-gamma/IL-10 ratio of < 1.0 (p = 0.015). The levels of IL-10 (p = 0.04) and IFN-gamma (p = 0.04) in the CSF in cases with cryptococcal meningitis were significantly higher than those in their serum, respectively.

CONCLUSIONS

High expression of Th2 phenotype in cryptococcal meningitis and in fungemia suggests that Th dysregulation may contribute to the pathogenesis of cryptococcosis in organ transplant recipients.

Impact of cytomegalovirus in organ transplant recipients in the era of antiviral prophylaxis

BACKGROUND

Antiviral prophylaxis has been shown to decrease the incidence of cytomegalovirus (CMV) disease in organ transplant recipients, but whether CMV disease that occurs despite prophylaxis is associated with mortality remains unknown.

METHODS

The clinical features and risk factors for CMV disease in a cohort of liver transplant recipients who received antiviral prophylaxis were assessed retrospectively. Cox proportional hazard regression was used to assess the relationship of CMV to mortality during the first posttransplant year.

RESULTS

CMV disease developed in 37 of 437 (8.5%) recipients at a median of 4.5 (range, 2.5 to 12) months posttransplant and was associated only with donor-seropositive/recipient-seronegative serostatus in multivariate analysis (P<0.0001). Mortality at 1 year was 12% (51 of 437) and was infection-associated in 49% of cases. In multivariate analysis, CMV disease was independently associated with overall mortality at 1 year (HR, 5.1, P=0.002) and even more strongly with infection-associated mortality (HR 11, P=0.002). There was no association of CMV with noninfection-associated mortality (P>0.05).

CONCLUSIONS

Late CMV disease is an important clinical problem in liver transplant recipients who receive antiviral prophylaxis, and is strongly and independently associated with mortality. Strategies to prevent late CMV disease are warranted.

A prospective cross-sectional study of BK virus infection in non-renal solid organ transplant recipients with chronic renal dysfunction

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 x 10(6) 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.

A prospective cross-sectional study of BK virus infection in non-renal solid organ transplant recipients with chronic renal dysfunction

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 x 10(6) 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.

Combination of Voriconazole and Caspofungin as Primary Therapy for Invasive Aspergillosis in Solid Organ Transplant Recipients: A Prospective, Multicenter, Observational Study

BACKGROUND

: The efficacy of the combination of voriconazole and caspofungin when used as primary therapy for invasive aspergillosis in organ transplant recipients has not been defined.

METHODS

: Transplant recipients who received voriconazole and caspofungin (n=40) as primary therapy for invasive aspergillosis (proven or probable) in a prospective multicenter study between 2003 and 2005 were compared to a control group comprising a cohort of consecutive transplant recipients between 1999 and 2002 who had received a lipid formulation of AmB as primary therapy (n=47). In vitro antifungal testing of Aspergillus isolates to combination therapy was correlated with clinical outcome.

RESULTS

: Survival at 90 days was 67.5% (27/40) in the cases, and 51% (24/47) in the control group (HR 0.58, 95% CI, 0.30-1.14, P=0.117). However, in transplant recipients with renal failure (adjusted HR 0.32, 95% CI: 0.12-0.85, P=0.022), and in those with A. fumigatus infection (adjusted HR 0.37, 95% CI: 0.16-0.84, P=0.019), combination therapy was independently associated with an improved 90-day survival in multivariate analysis. No correlation was found between in vitro antifungal interactions of the Aspergillus isolates to the combination of voriconazole and caspofungin and clinical outcome.

CONCLUSIONS

: Combination of voriconazole and caspofungin might be considered preferable therapy for subsets of organ transplant recipients with invasive aspergillosis, such as those with renal failure or A. fumigatus infection.

Late-onset invasive aspergillosis in organ transplant recipients in the current era

We assessed predictive factors and characteristics of patients with late-onset invasive aspergillosis in the current era of novel immunosuppressive agents. Forty transplant recipients with invasive aspergillosis were included in this prospective, observational study initiated in 2003 at our institutions. In 50% (20/40) of these patients, the infections were late-occurring. Receipt of sirolimus in conjunction with tacrolimus for refractory rejection or cardiac allograft vasculopathy (P=0.047) was significantly associated with late-onset infection. The use of depleting or non-depleting T or B-cell antibodies, either as induction or as antirejection therapy did not correlate with time to onset of invasive aspergillosis. Mortality at 90 days was 20% (4/20) for the patients with early-onset infection and 45% (9/20) for those with late-onset infection (P=0.17). Thus, nearly one-half of the Aspergillus infections in transplant recipients in the current era are late-occurring. These data have implications relevant for prophylactic strategies and guiding clinical management of transplant recipients presenting with pulmonary infiltrates.

Inconsistent localization of gram-positive bacteria to prostate-specific specimens from patients with chronic prostatitis

OBJECTIVES

To determine the rate of gram-positive localizations and whether repetitive cultures demonstrate consistent localization of gram-positive bacteria in patients with chronic prostatitis symptoms.

METHODS

We repeated localization cultures at different visits for untreated patients with chronic prostatitis symptoms.

RESULTS

A total of 470 patients with chronic prostatitis had lower urinary tract localization cultures done. Ten-fold increases in the concentrations of gram-positive bacteria were noted when the postprostatic massage (VB3) or expressed prostatic secretions cultures were compared with first-void urine (VB1) cultures from 29 patients (6%). This was comparable to the 7% rate of gram-negative chronic bacterial prostatitis. We studied 49 patients who had undergone 130 repeated localization studies (median 2, range 2 to 4). Repeatedly negative studies were found in 20 patients, including 19 who each had undergone two studies and 1 who had undergone four studies. Of 9 patients who each had undergone three or four studies, 9 demonstrated localization of at least one gram-positive species. Of the 29 patients with gram-positive localizations, 27 (94%) did not have consistent localization of the gram-positive species.

CONCLUSIONS

Patients with chronic prostatitis demonstrated localization of gram-positive bacteria, but the results were seldom reproducible in untreated patients. Gram-positive localizations may represent nonpathogens, transient bacterial colonization of the lower urinary tract, or intermittent shedding of prostatic pathogens. The limitations of traditional cultures highlight the need for better diagnostic approaches and improved recommendations for antimicrobial therapy.

Allograft Loss in Renal Transplant Recipients with Cryptococcus Neoformans Associated Immune Reconstitution Syndrome

This study describes the association of allograft loss and immune reconstitution syndrome (IRS) in the course of Cryptococcosis neoformans infection in renal transplant recipients. Patients comprised 54 renal allograft recipients with cryptococcosis in a prospective, multicenter study. IRS developed in 5.5% (3/54) of the renal transplant recipient with C. neoformans infection. The renal allograft was lost to chronic rejection in 66% (2/3) of the patients with cryptococcosis who developed IRS compared to 5.9% (3/51) of those who did not (P=0.012). Kaplan-Meier survival analysis showed that subsequent to cryptococcal infection the probability of allograft survival was significantly lower in patients who developed IRS compared to those who did not develop IRS (P=0.0004). Temporal association of graft loss with IRS suggests a common pathophysiologic basis for these entities with implications relevant for the optimal management of renal transplant recipients with cryptococcosis.