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With the need for organs far exceeding supply, donors previously exposed to hepatitis B (HBV) and hepatitis C (HCV) viral infections should be considered for transplantation. Although many centers have protocols for transplanting organs from HBV core antibody-positive (HBcAb+) donors into select recipients, in the era of direct-acting antivirals (DAAs), a new focus should be placed on HCV-positive donors. The transmission rate from HCV antibody-positive (HCVAb+) nucleic acid testing negative (HCV NAT-) donors is expected to be very low, and we encourage use of such organs in HCV recipients provided a normal biopsy, appropriate counseling, and careful post-transplant monitoring. While transmission of HCV from HCV NAT+ donors is universal, the success of DAA in obtaining a sustained viral response in post-transplant recipients should make the use of these organs more appealing. We herein provide information to help guide the use of organs from HCV donors.

BACKGROUND The WHO recently released a BK virus (BKV) international standard. This study evaluated the WHO international standard and commercially available BKV standards by quantitative real-time PCR (qPCR) and droplet digital PCR (ddPCR). METHODS WHO, Exact Diagnostics, Acrometrix, and Zeptometrix BKV standards were tested by qPCR and ddPCR. Two preparations of NIST BKV clones were also tested. Nucleic acid was extracted with the Roche MP96 and MPLC, followed by quantification in duplicate. To resolve discrepancies, we sequenced the WHO and NIST materials. RESULTS Manufacturers' expected copies/mL were close to WHO IU/mL: linear regression of qPCR data revealed 1.12 Exact copies/IU, 0.76 Acrometrix copies/IU, and 0.70 Zeptometrix copies/IU. For ddPCR, similar concentrations were measured when either the VP1 region or the T region was targeted, and concentrations were almost 2-fold higher when both regions were targeted simultaneously. ddPCR results for the VP1 and T regions were similar for all commercial standards, but targeting the T region of the WHO standard led to a 4-fold lower result than the VP1 region. Next-generation sequencing revealed no primer or probe mismatches. However, large differences in coverage across the WHO standard and junctional reads were observed, indicating subpopulations of the WHO standard with deletions in the T region. CONCLUSIONS BKV standards showed concordance among providers, but the WHO standard contains subpopulations of viruses with various deletions in the T region. PCR results will vary depending on which region of the WHO standard is targeted.

1. Schmitto JD, Rojas SV, Hanke JS, Avsar M, Haverich A. Minimally invasive left ventricular assist device explantation after cardiac recovery: surgical technical considerations. Artif Organs 2014;38: 507-10. 2. Rojas SV, Avsar M, Khalpey Z, Hanke JS, Haverich A, Schmitto JD. Minimally invasive off-pump left ventricular assist device exchange: anterolateral thoracotomy. Artif Organs 2014;38:539-42. 3. Schmitto JD, Hanke JS, Rojas SV, Avsar M, Haverich A. First implantation in man of a new magnetically levitated left ventricular assist device (HeartMate III). J Heart Lung Transplant 2015;34: 858-60. 4. Netuka I, Sood P, Pya Y, et al. Fully magnetically levitated left ventricular assist system for treating advanced HF: a multicenter study. J Am Coll Cardiol 2015;66:2579-89.

Chapter 2 focuses on the solid organ transplantation (SOT). The Solid organ transplantation (SOT) is undertaken to restore organ function for patients with failing or end-stage disease of the liver, heart, lung, kidneys, and/or pancreas or to re-establish function in patients with short gut or other disorders of the intestinal tract. Organ transplantation requires lifelong maintenance immune suppression to prevent organ rejection. Infection can be related to donor transmission, reactivation from latency in the recipient, or acquisition de novo post-transplant. The evaluation of suspected infection in SOT recipients is guided by the clinical presentation, with likelihood shaped by prophylaxis strategies, host factors, and exposure history. Prompt evaluation is critical, often requiring multimodality imaging, microbiologic testing with cultures and molecular diagnostics, and invasive diagnostics or biopsy. The chapter concludes that, through use of biomarkers and indicators of pathogen-specific immune competence as well as better laboratory assessment of overall immune competence, a more granular identification of those SOT recipients at highest risk for infection will allow for optimization of prophylaxis and other infection prevention strategies.

Cytomegalovirus (CMV) is the single most important pathogen affecting solid organ transplant (SOT) recipients. CMV may occur as a primary infection in CMV-naive patients after SOT, or it can be reactivation of latent donor or recipient infection in CMV-seropositive SOT recipients. CMV may present as a subclinical infection among SOT recipients with sufficient pathogen-specific immunity, or clinically apparent CMV-induced tissue damage, termed CMV disease, among SOT recipients without sufficient CMV specific immunity (such as CMV D+/R− SOT patients). CMV disease is manifested by fever, malaise, myelosuppression, and/or signs of end-organ involvement. CMV is also associated with numerous indirect effects, such as an increased risk of acute rejection, chronic allograft failure, and other opportunistic infections. Because of its negative impact, CMV prevention is a major focus of posttransplant management, accomplished either by preemptive therapy or antiviral prophylaxis. Treatment of CMV disease is accomplished by the use of intravenous ganciclovir or oral valganciclovir. Reduction in immunosuppression is recommended when dealing with severe cases of CMV disease. Resistance to ganciclovir is emerging, and may be treated with alternative drugs such as foscarnet and cidofovir. Several novel antiviral drugs are currently undergoing clinical trials for prevention and treatment of CMV disease.

To describe the trend of Acanthamoeba keratitis case reports following an outbreak and the recall of a multipurpose contact lens disinfection solution. Acanthamoeba keratitis is a serious eye infection caused by the free-living amoeba Acanthamoeba that primarily affects contact lens users.A convenience sample of 13 ophthalmology centers and laboratories in the USA, provided annual numbers of Acanthamoeba keratitis cases diagnosed between 1999-2009 and monthly numbers of cases diagnosed between 2007-2009. Data on ophthalmic preparations of anti-Acanthamoeba therapies were collected from a national compounding pharmacy.Data from sentinel site ophthalmology centers and laboratories revealed that the yearly number of cases gradually increased from 22 in 1999 to 43 in 2003, with a marked increase beginning in 2004 (93 cases) that continued through 2007 (170 cases; p0.0001). The outbreak identified from these sentinel sites resulted in the recall of a contact lens disinfecting solution. There was a statistically significant (p ≤ 0.0001) decrease in monthly cases reported from 28 cases in June 2007 (following the recall) to seven cases in June 2008, followed by an increase (p = 0.0004) in reported cases thereafter; cases have remained higher than pre-outbreak levels. A similar trend was seen in prescriptions for Acanthamoeba keratitis chemotherapy. Cases were significantly more likely to be reported during summer than during other seasons.The persistently elevated number of reported cases supports the need to understand the risk factors and environmental exposures associated with Acanthamoeba keratitis. Further prevention efforts are needed to reduce the number of cases occurring among contact lens wearers.

Background Immune measurements that distinguish solid organ transplantation (SOT) recipients who control cytomegalovirus (CMV) infection from those who progress to CMV-disease (CMV-dz) may be clinically useful in guiding tailored prevention strategies. We previously reported that elevated plasma levels of the immune-modulator IL-10 are associated with late CMV-dz. Here we evaluate whether IL-10 levels measured soon after prophylaxis discontinuation are predictive of CMV-dz risk. Methods Plasma IL-10 levels were quantitatively measured by ELISA kit in 40 D/R SOT patients. All 40 D/R high-risk patients were prospectively followed for at least 12 months post-SOT: 13 subjects developed CMV-dz, all within 6 months of prophylaxis discontinuation. Results IL-10 was detectable at the first post-prophylaxis measurement for 11 of 13 subjects who developed CMV-dz. In contrast, IL-10 was detectable in only 6 of 27 CMV asymptomatic patients. Monitoring IL-10 plasma levels within 1 month prophylaxis suspension appeared to have clinically useful level of 85% sensitivity and 78% specificity. Conclusions The exact role of IL-10 with its multiple immunoregulatory effects during CMV infection is not clear. Moreover, IL-10 production can be influenced by pathological and infectious contexts, and/or anti-rejection immunosuppressant therapy. Despite mechanisms of IL-10 dysregulation may substantially differ among SOT patients, our findings suggest that measurable plasma IL-10 soon after prophylaxis discontinuation may be an adequate indicator of subsequent CMV-dz. If a similar prognostic performance is confirmed in a larger D/R cohort, IL-10 plasma levels could be used to guide the length of prophylaxis, providing a clinically useful means to reduce the incidence of CMV-dz in high risk patients.

The Kidney Donor Risk Index (KDRI) and Kidney Donor Profile Index (KDPI) assist clinicians with the selection of deceased donor kidneys. This scoring system is based on 10 donor factors including Hepatitis C virus (HCV) status from serological or NAT testing. The donor HCV status (i.e., having either a positive hepatitis C antibody (Ab) or nucleic acid testing (NAT) result) increases the hazard ratio for graft failure by 1.27 and the KDPI by approximately 20%. Whether this increase in KDPI is a true reflection of graft quality for HCV seropositive but not viremic donors is unknown. Further investigations are needed to maximize the use of these organs.

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.

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.

Antiviral prophylaxis has become a commonly used strategy for prevention of cytomegalovirus (CMV) disease in seronegative recipients of an organ from a CMV-seropositive donor (D+ R−) and has typically been given for 3–6 months post transplant (1). Despite significant reductions in the incidence of CMV with this approach, 20–40% of D+ R− patients still develop CMV disease after discontinuation of antiviral prophylaxis. CMV disease in this setting (termed ‘late-onset CMV’) is an important clinical problem that is associated with significant morbidity (2–4). Optimal approaches for preventing late-onset disease have not been fully defined, but have included extending the duration of prophylaxis, viral monitoring and preemptive therapy after discontinuation of prophylaxis, or enhanced surveillance for clinical symptoms and early treatment. Although it is well established that D+ R− transplant patients as a group are at significantly higher risk of late-onset CMV disease compared with seropositive (R +) patients, the risk factors within the D+ R− group have not been well defined. If specific clinical or transplant variables predictive of late-onset CMV disease could be identified within this group, it might be possible to design a more rational targeted CMV prevention strategy for those D+ R− patients at greatest risk. We are aware of only 4 previously published studies that analyzed risk factors for late-onset CMV in D+ R− kidney transplant recipients who received antiviral prophylaxis (4–7). Among these, 2 combined results of kidney with other transplant recipients (4, 6), making it difficult to determine which risk factors might specifically be related to kidney transplant without confounding by the other organ transplant. Thus, given the limited data regarding the risk factors for late-onset CMV disease in D+ R− kidney transplant recipients who receive antiviral prophylaxis, we retrospectively assessed the association of multiple demographic and transplant variables with CMV disease in a cohort of adult D+ R− kidney transplant recipients at a single US kidney transplant center.

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 SOTand received follow-up care within the large multicenter US Department of Veteran's Aiairs healthcare system. Methods. Incident cases of HZ were determined using ICD-9 coding from administrative databases. A multivariable Cox proportional hazards model, adjusted for ap rioririsk factors, was used to assess demographic factors associated with development of HZ. Results. Among the 1077 eligible SOT recipients, the cohort-speci¢c incidence rate of HZ was 22.2 per 1000 patient-years (95% con¢dence 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.

Background Current guidelines preferentially recommend valganciclovir (VGCV) prophylaxis over PET in most D+R− organ transplant populations, but adequately powered direct comparative clinical trials are lacking. Methods D+R− LTR were randomly assigned (1:1, stratified by site and T-cell depleting induction) to receive either PET (weekly plasma CMV DNAemia at central laboratory for 100 days, with VGCV 900 mg bid for DNAemia at any level, until two consecutive negative weekly tests) or prophy (VGCV 900 mg qd for 100 days). The primary outcome was CMV disease by 12 months as adjudicated by an independent, blinded, endpoint committee in ITT population. Secondary outcomes were opportunistic infections (OIs) (invasive fungal and bacterial), neutropenia (ANC < 1000/µL), acute rejection, graft loss, and mortality assessed at12 months. Results From October 2012 to June 2017, 205 patients were randomized at six centers; 100 to PET, 105 to prophy. The incidence of CMV disease was 9% (9/100) in PET and 19% (20/105) in prophy (P = 0.039) with majority of difference due to post-prophylaxis disease: 6% in PET vs. 17% in prophy (P = 0.027). CMV disease included syndrome in 55% (16/29) and end-organ in 45% (13/29), with similar proportions in two groups. Secondary outcomes were not different for PET and prophy groups: OIs (19% vs. 21%), neutropenia (34% vs.. 28%), acute rejection (27% vs. 27%), graft loss (2% vs. 2%), and mortality (10% vs. 6%), respectively, P > 0.05 for all comparisons. Mortality at last follow-up (median 3.2 years) was not different for PET vs. prophy (14% vs. 18%, P = 0.43). Conclusions PET significantly reduced the incidence of CMV disease compared with prophy in D+R- LTR, and was associated with similar other clinical outcomes. Current guidelines should be revised to recommend PET over prophylaxis in this setting, and similar trials conducted in other D+R− transplant populations. (Funded by NIAID; ClinicalTrials.gov# NCT01552369.) Disclosures D. Winston, Merck: Investigator, Research support. Chimerix: Investigator, Research support. Shire: Investigator, Research support. Gilead: Investigator, Research support. Oxford Immunotech: Investigator, Research support. G. M. Lyon III, Shire: Investigator, institutional research support. Hookipa: Investigator, institutional research support. Merck: Investigator, institutional research support. F. P. Silveira, Shire: contracted clinical research, site investigator. A. P. Limaye, Merk: Consultant and Investigator, Consulting fee and Research grant. Astellas Pharma Inc.: Consultant and Investigator, Consulting fee. Helocyte Inc.: Consultant, Consulting fee.

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 define 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

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.

Cytomegalovirus (CMV) is the single most important viral pathogen that affects recovery of immunosuppressed transplant recipients (1). Antiviral prophylaxis for 3 months post transplant, used by ~90% of American solid organ transplant (SOT) centers, reduces the incidence of CMV disease to

BK virus nephropathy (BKPyVAN) is a major complication in kidney transplant recipients (KTR) and typically occurs within 1 year of transplant. Guidelines vary in recommendations for BKPyV screening beyond 1 year. A systematic characterization of risk factors and outcomes of late-onset (1 year) BKPyVAN has not previously been reported.We retrospectively compared characteristics and outcomes of early- (1 year) and late-onset BKPyVAN (definitive [biopsy-confirmed] or presumptive [plasma BKPyV10 000 copies/mL]) in a cohort of 671 KTR and simultaneous kidney-pancreas transplant (SPK) recipients between 2008 and 2013 at a single US transplant center. Proportions were compared using Chi-square or Fisher's exact test with P .05 considered significant.BKPyVAN was diagnosed in 96 (14.3%) patients (proven 16.7%, presumptive 83.3%): 79 (82.3%) early- and 17 (17.7%) late-onset. The proportion with late-onset BKPyVAN was significantly higher among SPK than KTR (4 of 7 [57.1%] vs 13 of 89 [14.6%], P = .017). Late-onset represented "de novo" infection (no BKPyV detection within the first year) in 14 (82.4%) and progression of earlier lower grade BKPyV reactivation in 3 (17.6%). Clinical outcomes were similar for early- and late-onset BKPyVAN (P .05 all comparisons). In a pooled analysis of prior studies of BKPyVAN in SPK recipients, 62.9% (17 of 27) were late-onset.A significant proportion of BKPyVAN is late-onset, especially among SPK recipients, and supports a longer duration of BKPyV monitoring for SPK recipients than recommended in some guidelines.

As outcomes of transplantation have improved, the number of transplant candidates listed for deceased donor transplantation has increased significantly over the years. Organ shortage is one of the greatest challenges facing the field of organ transplantation. Until recently, organs from donors who tested for hepatitis C virus (HCV) have been used exclusively in recipients with chronic HCV infection or were discarded at a high rate. This article is protected by copyright. All rights reserved.

herpesvirus family. VZV is presentworldwide and is highly infectious. Primary infection leadsto acute varicella or ‘chickenpox,’ usually from exposureeither through direct contact with a skin lesion or throughairborne spread from respiratory droplets (1,2). After initialinfection, VZV establishes lifelong latency in cranial nerveanddorsalrootganglia,andcanreactivateyearstodecadeslater as herpes zoster (HZ) or ‘shingles’ (3). More than90% of adults in the United States acquired the disease inchildhood, while the majority of children and young adultshave been vaccinated with the live virus vaccine (2,4).Primary varicella typically presents with fever, constitu-tional symptoms and a vesicular, pruritic, widely dissem-inated rash that primarily involves the trunk and face (5).Thesymptomsusuallyresolvewithin7–10days,butinrarecases primary varicella leads to more severe disease andvisceral invasion. Complications, such as hepatitis, pancre-atitis, pneumonitis and encephalitis are infrequent but canbelife-threatening;adultsandveryyoungchildrenaremorelikely to develop such complications from primary infection(6,7). Rates of hospitalization and mortality due to varicellahave dropped with the institution of routine childhood vari-cella vaccination (8,9).Nearly all patients with HZ develop an exanthem of vesic-ular lesions in a dermatomal distribution. The annual inci-dence of HZ in the general population is 1.5–3.0 cases per1000 persons (2), and is estimated to occur in up to 20%of individuals during their lifetime (10). Secondary compli-cations such as bacterial superinfection and postherpeticneuralgia (PHN), or chronic neuropathic pain at the site ofHZ, lead to increased morbidity (11).Over 90% of adult solid organ transplant (SOT) recipientswill be seropositive for VZV. Rates are lower in pediatrictransplants(12,13),butimmunitywillincreaseasuptakeofvaricella vaccine improves. Varicella is rare in adult SOT re-cipients,butcanbedevastating,withvisceralinvolvement,severe skin disease, and disseminated intravascular coag-ulation (14–19). HZ is a frequent infectious complication inSOT recipients with an incidence of approximately 8–11%during the first 4 years posttransplant (20–22). Invasive dis-ease and dissemination similar to that seen in primary VZVinfection are uncommon but have been reported in SOTand other immunocompromised populations, and level ofimmunosuppression may alter the risk of developing thesecomplications (17,23,24). Rates of PHN in SOT recipi-ents may also be higher than in immunocompetent popu-lations (22).

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.

Background. Prognostic implications of cryptococcal antigen and outcomes associated with central nervous system (CNS) cryptococcal lesions in solid organ transplant recipients have not been fully defined.Methods. Patients were derived form a cohort of 122 solid organ transplant recipients with cryptococcosis in a multicenter study from 1999 to 2006.Results. Central nervous system cryptococcosis was documented in 61 patients. Serum or cerebral spinal fluid antigen titers did not correlate with mortality at 90 days or cerebral spinal fluid sterilization at 2 weeks. Central nervous system lesions were identified in 16 patients and included leptomeningeal lesions in eight, parenchymal lesions in six, and hydrocephalus in two. Overall, 13/16 CNS lesions were present at the time of diagnosis. One parenchymal and two hydrocephalus lesions, however, developed after diagnosis and fulfilled the criteria for immune reconstitution syndrome. Cerebral spinal fluid antigen titers were higher with meningeal versus parenchymal lesions, and hydrocephalus (P = 0.015). Mortality was 50% (3/6) for patients with parenchymal, 12.5% (1/8) for those with leptomeningeal, and 0/3 for patients with hydrocephalus. Mortality was 31% (4/13) for patients with CNS lesions at baseline and 0/3 in those with new onset lesions.Conclusions. Despite a higher antigen titer with meningeal lesions, outcomes tended to be worse with parenchymal compared with meningeal lesions or hydrocephalus. New onset CNS lesions may represent immune reconstitution syndrome and seemed to be associated with better outcome.

Synergistic interactions were observed between CIs and antifungal agents against 53 (90%) of 59 Cryptococcus neoformans isolates from solid organ transplant recipients with cryptococcosis and may account for better outcomes in patients with cryptococcosis receiving these immunosuppressive agents.

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 (Pp.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.

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.

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.

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

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.

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.

Background Gastrointestinal (GI) cytomegalovirus (CMV) disease is the most common manifestation of tissue-invasive CMV infection in solid organ transplant (SOT) recipients, but the diagnostic yields of blood and tissue testing have not been systematically assessed in a large patient cohort. Methods We retrospectively identified consecutive SOT recipients with biopsy-confirmed GI CMV disease who had both tissue and blood (CMV polymerase chain reaction or antigenemia) diagnostic testing performed within 14 days of diagnosis. Descriptive statistics and logistic regression were used to assess the association between patient factors and viremia and the diagnostic yield of tests performed on biopsy specimens. Results A total of 101 patients (73% donor seropositive/recipient seronegative [D+/R-], 22% recipient seropositive [R+]) had GI CMV disease (58% upper, 22% lower, and 20% both) at a median of 185 days (range, 21-6345 days) post transplant. In multivariate analysis, R+ CMV serostatus (odds ratio [OR] 0.1 [0.0-0.4], P 6 months post transplant (OR 0.3 [0.1-0.9], P = 0.03) were each independently associated with absence of CMV viremia at time of diagnosis. In the subset of patients (n = 29) in whom both histopathology and viral culture were performed on biopsy specimens, 11 (39%) had CMV detected only by culture and had similar clinical characteristics and outcomes to those with positive histopathology (P > 0.05 for all comparisons). Conclusions The sensitivity of viremia in SOT recipients with GI CMV disease is significantly lower in CMV-seropositive patients and in those >6 months post transplant. Addition of viral culture to endoscopic biopsy specimens significantly increases the diagnostic yield for GI CMV disease.

Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. Background. The utility of Aspergillus galactomannan (GM) and β-D-glucan (BG) in liver transplant recipients remains uncertain. Methods. As part of a randomized, double-blind trial of antifungal prophylaxis in liver transplant recipients at risk for invasive fungal infections (IFIs), GM and BG were assessed in 199 patients at baseline (enrollment) and weekly thereafter for the duration of study drug. Receiver operating characteristic (ROC) analysis was used to evaluate the accuracy of these for the diagnosis of IFIs. Results. Overall, 46.4% of the patients at baseline had positiveGM(index ≥ 0.5) and 89.6%had BG of 80 pg/mL or greater with BG level of 500 pg/mL or greater in 31.8%. Patients with invasive aspergillosis (IA) (3/3) had positive GM at baseline as did 45.5% of those without IA (P = 0.098); the area under the ROC curve for the diagnosis of IA was 0.77 (fair test, ie, good sensitivity but poor specificity). Using BG cutoff of 80 pg/mL or higher, 100%(12/12) of the patients with IFI had positive baseline BGand as did 88.9% (160/180) of those without IFI (P = 0.618); the area under the ROC curve for predicting IFIs was 0.56 (poor test). In multivariate analyses, GM positivity was associated with study site (P = 0.041), and BG positivity with renal replacement therapy (P = 0.05) and study site (P = 0.01). The GM and BG levels declined over time; positivity at subsequent time points was lower in comparison with baseline (P < 0.001). Conclusions. The GM and BG tests had significant center variability and limited accuracy for the diagnosis of IFIs in high-risk liver transplant recipients.

Background Mycobacterium abscessus infection in patients with cystic fibrosis (CF) can result in accelerated clinical decline and the potential for direct or indirect transmission between patients has been recently demonstrated. Data on the outcomes of M abscessus outbreaks and the efficacy of specific infection control procedures in patients with CF remain limited. This study provides follow-up from an outbreak of pulmonary M abscessus in our center, highlighting outcomes and strategies that appear to have prevented further spread of the organism. Methods Data from our adult CF center (1989-2015) were analyzed, including chart reviews of all patients with positive mycobacterial sputum cultures, cultures from environment surfaces, and epidemiologic evaluation of infected patients. Following an M abscessus outbreak in 2009, infection control policies were intensified based on CF guidelines and surveillance data were collected and reviewed. Results Five cases of M abscessus were involved in the outbreak; 3 patients died during follow-up. An environment search failed to reveal an intermediary source of transmission between patients. After implementation of infection control measures composed of staff/patient education, environment sterilization, and patient isolation, no new cases were detected. Conclusions Direct or indirect patient-to-patient transmission of M abscessus is a threat in the CF population. A multifaceted infection control strategy based on CF guidelines was effective in halting transmission in our center.

BACKGROUND Chronic lung allograft dysfunction (CLAD) is a major cause of allograft loss post-lung transplantation. Prior studies have examined the association between respiratory virus infection (RVI) and CLAD were limited by older diagnostic techniques, study design, and case numbers. We examined the association between symptomatic RVI and CLAD using modern diagnostic techniques in a large contemporary cohort of lung transplant recipients (LTRs). METHODS We retrospectively assessed clinical variables including acute rejection, cytomegalovirus pneumonia, upper and lower RVI, and the primary endpoint of CLAD (determined by 2 independent reviewers) in 250 LTRs in a single university transplantation program. Univariate and multivariate Cox models were used to analyze the relationship between RVI and CLAD in a time-dependent manner, incorporating different periods of risk following RVI diagnosis. RESULTS Fifty patients (20%) were diagnosed with CLAD at a median of 95 weeks post-transplantation, and 79 (32%) had 114 episodes of RVI. In multivariate analysis, rejection and RVI were independently associated with CLAD (adjusted hazard ratio [95% confidence interval]) 2.2 (1.2-3.9), P = .01 and 1.9 (1.1-3.5), P = .03, respectively. The association of RVI with CLAD was stronger the more proximate the RVI episode: 4.8 (1.9-11.6), P < .01; 3.4 (1.5-7.5), P < .01; and 2.4 (1.2-5.0), P = .02 in multivariate analysis for 3, 6, and 12 months following RVI, respectively. CONCLUSIONS Symptomatic RVI is independently associated with development of CLAD, with increased risk at shorter time periods following RVI. Prospective studies to characterize the virologic determinants of CLAD and define the underlying mechanisms are warranted.

Human herpesvirus 6 is associated with a variety of complications in immunocompromised patients, but no studies have systematically and comprehensively assessed the impact of human herpesvirus 6 reactivation, and its interaction with cytomegalovirus, in ICU patients.We prospectively assessed human herpesvirus 6 and cytomegalovirus viremia by twice-weekly plasma polymerase chain reaction in a longitudinal cohort study of 115 adult, immunocompetent ICU patients. The association of human herpesvirus 6 and cytomegalovirus reactivation with death or continued hospitalization by day 30 (primary endpoint) was assessed by multivariable logistic regression analyses.This study was performed in trauma, medical, surgical, and cardiac ICUs at two separate hospitals of a large tertiary care academic medical center.A total of 115 cytomegalovirus seropositive, immunocompetent adults with critical illness were enrolled in this study.None.Human herpesvirus 6 viremia occurred in 23% of patients at a median of 10 days. Human herpesvirus 6B was the species detected in eight samples available for testing. Most patients with human herpesvirus 6 reactivation also reactivated cytomegalovirus (70%). Severity of illness was not associated with viral reactivation. Mechanical ventilation, burn ICU, major infection, human herpesvirus 6 reactivation, and cytomegalovirus reactivation were associated with the primary endpoint in unadjusted analyses. In a multivariable model adjusting for mechanical ventilation and ICU type, only coreactivation of human herpesvirus 6 and cytomegalovirus was significantly associated with the primary endpoint (adjusted odds ratio, 7.5; 95% CI, 1.9-29.9; p = 0.005) compared to patients with only human herpesvirus 6, only cytomegalovirus, or no viral reactivation.Coreactivation of both human herpesvirus 6 and cytomegalovirus in ICU patients is associated with worse outcome than reactivation of either virus alone. Future studies should define the underlying mechanism(s) and determine whether prevention or treatment of viral reactivation improves clinical outcome.

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.

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

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.

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.

A transgenic mouse model was used to identify an HLA-A*02-restricted epitope within the VP1 polypeptide of a human polyomavirus, BK virus (BKV), which is associated with polyomavirus-associated nephropathy in kidney transplant patients. Peptide stimulation of splenocytes from mice immunized with recombinant modified vaccinia virus Ankara expressing BKV VP1 resulted in expansion of cytotoxic T lymphocytes (CTLs) recognizing the sequence LLMWEAVTV corresponding to amino acid residues 108 to 116 (BKV VP1p108). These effector T-cell populations represented functional CTLs as assessed by cytotoxicity and cytokine production and were cross-reactive against antigen-presenting cells pulsed with a peptide corresponding to the previously described JC virus (JCV) VP1 homolog sequence ILMWEAVTL (JCV VP1p100) (I. J. Koralnik et al., J. Immunol. 168: 499-504, 2002). A panel of 10 healthy HLA-A*02 human volunteers and two kidney transplant recipients were screened for T-cell immunity to this BK virus VP1 epitope by in vitro stimulation of their peripheral blood mononuclear cells (PBMC) with the BKV VP1p108 peptide, followed by tetramer labeling combined with simultaneous assays to detect intracellular cytokine production and degranulation. PBMC from 4/10 subjects harbored CTL populations that recognized both the BKV VP1p108 and the JCV VP1p100 peptides with comparable efficiencies as measured by tetramer binding, gamma interferon production, and degranulation. CTL responses to the JCV VP1p100 epitope have been associated with prolonged survival in progressive multifocal leukoencephalopathy patients (R. A. Du Pasquier et al., Brain 127: 1970-1978, 2004; I. J. Koralnik et al., J. Immunol. 168: 499-504, 2002). Given that both human polyomaviruses are resident in a high proportion of healthy individuals and that coinfection occurs (W. A. Knowles et al., J. Med. Virol. 71: 115-123, 2003), our findings suggest a reinterpretation of this protective T-cell immunity, suggesting that the same VP1 epitope is recognized in HLA-A*02 persons in response to either BK or JC virus infection.

Background. We describe an immune reconstitution syndrome (IRS)-like entity in the course of evolution of Cryptococcus neoformans infection in organ transplant recipients. Methods. The study population comprised a cohort of 83 consecutive organ transplant recipients with cryptococcosis who were observed for a median of 2 years in an international, multicenter study. Results. In 4 (4.8%) of the 83 patients, an IRS-like entity was observed a median of 5.5 weeks after the initiation of appropriate antifungal therapy. Worsening of clinical manifestations was documented, despite cultures being negative for C. neoformans. These patients were significantly more likely to have received tacrolimus, mycophenolate mofetil, and prednisone as the regimen of immunosuppressive therapy than were all other patients (P = .007). The proposed basis of this phenomenon is reversal of a predominantly Th2 response at the onset of infection to a Thi proinflammatory response as a result of receipt of effective antifungal therapy and a reduction in or cessation of immunosuppressive therapy. Conclusions. This study demonstrated that an IRS-like entity occurs in organ transplant recipients with C. neoformans infection. Furthermore, this entity may be misconstrued as a failure of therapy. Immunomodulatory agents may have a role as adjunctive therapy in such cases.

Polyomavirus-associated nephropathy (PVAN) is an emerging cause of kidney transplant failure affecting 1-10% of patients. As uncertainty exists regarding risk factors, diagnosis, and intervention, an independent panel of experts reviewed the currently available evidence and prepared this report. Most cases of PVAN are elicited by BK virus (BKV) in the context of intense immunosuppression. No specific immunosuppressive drug is exclusively associated with PVAN, but most cases reported to date arise while the patient is on triple immunosuppressive combinations, often comprising tacrolimus and/or mycophenolate mofetil plus corticosteroids. Immunologic control of polyomavirus replication can be achieved by reducing, switching, and/or discontinuing components of the immunosuppressive regimen, but the individual's risk of rejection should be considered. The success rate of this intervention is increased with earlier diagnosis. Therefore, it is recommended that all renal transplant recipients should be screened for BKV replication in the urine: 1) every three months during the first two years posttransplant; 2) when allograft dysfunction is noted; and 3) when allograft biopsy is performed. A positive screening result should be confirmed in

We developed a strategy to determine the clinical impact associated with errors in clinical microbiology testing. Over a 9-month period, we used a sequential three-stage method to prospectively evaluate 480 consecutive corrected microbiology laboratory reports. The three stages were physician review of the corrected report, medical record review, and interview with the clinician(s) taking care of the patient. Of the 480 corrected reports, 301 (62.7%) were ruled out for significant clinical impact by physician review and an additional 25 cases (5.2%) were ruled out for clinical impact by medical record review. This left 154 cases (32.1%) that required clinician interview to determine clinical impact. The clinician interview revealed that 32 (6.7%) of the corrected reports were associated with adverse clinical impact. Of these 32 cases, 19 (59.4%) involved delayed therapy, 8 (25.0%) involved unnecessary therapy, 8 (25.0%) were associated with inappropriate therapy, and 4 (12.5%) were associated with an increased level of care. The laboratory was entirely responsible for the error in 28 (87.5%) of the 32 cases and partially responsible in the other 4 cases (12.5%). Twenty-six (81.3%) of the 32 cases involved potentially preventable analytic errors that were due to lack of knowledge (cognitive error). In summary, we used evaluation of corrected reports to identify laboratory errors with adverse clinical impact, and most of the errors were amenable to laboratory-based interventions. Our method has the potential to be implemented in other laboratory settings to identify and characterize errors that impact patient safety.

Chronic renal dysfunction is common in non-renal solid organ (SOT) and hematopoietic stem cell transplant (HSCT) recipients and is commonly attributed to calcineurin inhibitor toxicity, often without renal histopathologic evaluation. Polyomavirus nephropathy (PVN) is an important cause of allograft dysfunction in kidney transplant recipients but has rarely been reported in native kidneys of non-renal transplant recipients. We report the clinical, pathologic and virologic features of PVN in native kidneys of two allograft recipients. In both, severe renal dysfunction was accompanied by histopathologic evidence of PVN, including characteristic viral inclusions by routine stains, immunohistochemistry and electron microscopy. High levels of BK virus (BKV) DNA were detected in kidney tissue of patients using BKV-specific polymerase chain reaction (PCR). In 1 patient, high levels of BKV DNA were detected in plasma and urine, and administration of low-dose cidofovir was associated with clearance of BK viremia. These results extend the populations in which PVN has been documented in native kidneys to include heart and stem cell transplant recipients, and suggest that cidofovir has activity against BKV in vivo. Studies to define the incidence and potential contribution of PVN to chronic renal dysfunction commonly attributed to calcineurin inhibitor toxicity in non-renal transplant recipients are warranted.

Given the limited information regarding BK virus-associated nephropathy (BKVN) in pediatric kidney transplant recipients, we assessed the incidence, risk factors, clinical and virologic features of BKVN in pediatric renal transplant recipients at a single transplant center by means of a retrospective cohort study. Histologically confirmed BKVN developed in 6 of 173 (3.5%) kidney transplant recipients at a median of 15 months post-transplant (range: 4-47 months). At a median follow-up of 28 months (range: 5-32), all patients had functioning grafts with mean creatinine and GFR of 1.9 mg/dL and 58 mL/min/1.73 m2, respectively. At the time of diagnosis, all cases had viruria (median 6.1 x 10(6) copies/mL, range: 10(5) to 3.9 x 10(8) copies/mL) and viremia (median 21,000 copies/mL, range: 10,000-40,000 copies/mL). Recipient seronegativity for BKV was significantly associated with the development of BKVN (p = 0.01). BKVN is an important cause of late allograft dysfunction and is strongly associated with recipient seronegativity in pediatric kidney transplant recipients. Further studies to confirm this finding and to define the clinical utility of routine pre-transplant BKV serologic testing are warranted.