958 resultados para failure factors


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INTRODUCTION Data concerning outcome after management of acetabular fractures by anterior approaches with focus on age and fractures associated with roof impaction, central dislocation and/or quadrilateral plate displacement are rare. METHODS Between October 2005 and April 2009 a series of 59 patients (mean age 57 years, range 13-91) with fractures involving the anterior column was treated using the modified Stoppa approach alone or for reduction of displaced iliac wing or low anterior column fractures in combination with the 1st window of the ilioinguinal approach or the modified Smith-Petersen approach, respectively. Surgical data, accuracy of reduction, clinical and radiographic outcome at mid-term and the need for endoprosthetic replacement in the postoperative course (defined as failure) were assessed; uni- and multivariate regression analysis were performed to identify independent predictive factors (e.g. age, nonanatomical reduction, acetabular roof impaction, central dislocation, quadrilateral plate displacement) for a failure. Outcome was assessed for all patients in general and in accordance to age in particular; patients were subdivided into two groups according to their age (group "<60yrs", group "≥60yrs"). RESULTS Forty-three of 59 patients (mean age 54yrs, 13-89) were available for evaluation. Of these, anatomic reduction was achieved in 72% of cases. Nonanatomical reduction was identified as being the only multivariate predictor for subsequent total hip replacement (Adjusted Hazard Ratio 23.5; p<0.01). A statistically significant higher rate of nonanatomical reduction was observed in the presence of acetabular roof impaction (p=0.01). In 16% of all patients, total hip replacement was performed and in 69% of patients with preserved hips the clinical results were excellent or good at a mean follow up of 35±10 months (range: 24-55). No statistical significant differences were observed between both groups. CONCLUSION Nonanatomical reconstruction of the articular surfaces is at risk for failure of joint-preserving management of acetabular fractures through an isolated or combined modified Stoppa approach resulting in total joint replacement at mid-term. In the elderly, joint-preserving surgery is worth considering as promising clinical and radiographic results might be obtained at mid-term.

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Background Escherichia coli is a common cause of asymptomatic and symptomatic bacteriuria in hospitalized patients. Asymptomatic bacteriuria (ASB) is frequently treated with antibiotics without a clear indication. Our goal was to determine patient and pathogen factors suggestive of ASB. Methods We conducted a 12-month prospective cohort study of adult inpatients with E. coli bacteriuria seen at a tertiary care hospital in St. Louis, Missouri, USA. Urine cultures were taken at the discretion of treating physicians. Bacterial isolates were tested for 14 putative virulence genes using high-throughput dot-blot hybridization. Results The median age of the 287 study patients was 65 (19–101) years; 78% were female. Seventy percent had community-acquired bacteriuria. One-hundred ten (38.3%) patients had ASB and 177 (61.7%) had symptomatic urinary tract infection (sUTI). Asymptomatic patients were more likely than symptomatic patients to have congestive heart failure (p = 0.03), a history of myocardial infarction (p = 0.01), chronic pulmonary disease (p = 0.045), peripheral vascular disease (p = 0.04), and dementia (p = 0.03). Patients with sUTI were more likely to be neutropenic at the time of bacteriuria (p = 0.046). Chronic pulmonary disease [OR 2.1 (95% CI 1.04, 4.1)] and dementia [OR 2.4 (95% CI 1.02, 5.8)] were independent predictors for asymptomatic bacteriuria. Absence of pyuria was not predictive of ASB. None of the individual virulence genes tested were associated with ASB nor was the total number of genes. Conclusions Asymptomatic E. coli bacteriuria in hospitalized patients was frequent and more common in patients with dementia and chronic pulmonary disease. Bacterial virulence factors could not discriminate symptomatic from asymptomatic bacteriurias. Asymptomatic E. coli bacteriuria cannot be predicted by virulence screening.

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Cardiolipin (CL) is responsible for modulation of activities of various enzymes involved in oxidative phosphorylation. Although energy production decreases in heart failure (HF), regulation of cardiolipin during HF development is unknown. Enzymes involved in cardiac cardiolipin synthesis and remodeling were studied in spontaneously hypertensive HF (SHHF) rats, explanted hearts from human HF patients, and nonfailing Sprague Dawley (SD) rats. The biosynthetic enzymes cytidinediphosphatediacylglycerol synthetase (CDS), phosphatidylglycerolphosphate synthase (PGPS) and cardiolipin synthase (CLS) were investigated. Mitochondrial CDS activity and CDS-1 mRNA increased in HF whereas CDS-2 mRNA in SHHF and humans, not in SD rats, decreased. PGPS activity, but not mRNA, increased in SHHF. CLS activity and mRNA decreased in SHHF, but mRNA was not significantly altered in humans. Cardiolipin remodeling enzymes, monolysocardiolipin acyltransferase (MLCL AT) and tafazzin, showed variable changes during HF. MLCL AT activity increased in SHHF. Tafazzin mRNA decreased in SHHF and human HF, but not in SD rats. The gene expression of acyl-CoA: lysocardiolipin acyltransferase-1, an endoplasmic reticulum MLCL AT, remained unaltered in SHHF rats. The results provide mechanisms whereby both cardiolipin biosynthesis and remodeling are altered during HF. Increases in CDS-1, PGPS, and MLCL AT suggest compensatory mechanisms during the development of HF. Human and SD data imply that similar trends may occur in human HF, but not during nonpathological aging, consistent with previous cardiolipin studies.

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BACKGROUND Patients with femoroacetabular impingement (FAI) often develop pain, impaired function, and progression of osteoarthritis (OA); this is commonly treated using surgical hip dislocation, femoral neck and acetabular rim osteoplasty, and labral reattachment. However, results with these approaches, in particular risk factors for OA progression and conversion to THA, have varied. QUESTIONS/PURPOSES We asked if patients undergoing surgical hip dislocation with labral reattachment to treat FAI experienced (1) improved hip pain and function; and (2) prevention of OA progression; we then determined (3) the survival of the hip at 5-year followup with the end points defined as the need for conversion to THA, progression of OA by at least one Tönnis grade, and/or a Merle d'Aubigné-Postel score less than 15; and calculated (4) factors predicting these end points. METHODS Between July 2001 and March 2003, we performed 146 of these procedures in 121 patients. After excluding 35 patients (37 hips) who had prior open surgery and 11 patients (12 hips) who had a diagnosis of Perthes disease, this study evaluated the 75 patients (97 hips, 66% of the procedures we performed during that time) who had a mean followup of 6 years (range, 5-7 years). We used the anterior impingement test to assess pain, the Merle d'Aubigné-Postel score to assess function, and the Tönnis grade to assess OA. Survival and predictive factors were calculated using the method of Kaplan and Meier and Cox regression, respectively. RESULTS The proportion of patients with anterior impingement decreased from 95% to 17% (p < 0.001); the Merle d'Aubigné-Postel score improved from a mean of 15 to 17 (p < 0.001). Seven hips (7%) showed progression of OA and another seven hips (7%) converted to THA Survival free from any end point (THA, progression of OA, or a Merle d'Aubigné-Postel < 15) of well-functioning joints at 5 years was 91%; and excessive acetabular rim trimming, preoperative OA, increased age at operation, and weight were predictive factors for the end points. CONCLUSIONS At 5-year followup, 91% of patients with FAI treated with surgical hip dislocation, osteoplasty, and labral reattachment showed no THA, progression of OA, or an insufficient clinical result, but excessive acetabular trimming, OA, increased age, and weight were associated with early failure. To prevent early deterioration of the joint, excessive rim trimming or trimming of borderline dysplastic hips has to be avoided.

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AIMS To assess incidence rates (IRs) of and identify risk factors for incident severe hypoglycaemia in patients with type 2 diabetes newly treated with antidiabetic drugs. METHODS Using the UK-based General Practice Research Database, we performed a retrospective cohort study between 1994 and 2011 and a nested case-control analysis. Ten controls from the population at risk were matched to each case with a recorded severe hypoglycaemia during follow-up on general practice, years of history in the database and calendar time. Using multivariate conditional logistic regression analyses, we adjusted for potential confounders. RESULTS Of 130,761 patients with newly treated type 2 diabetes (mean age 61.7 ± 13.0 years), 690 (0.5%) had an incident episode of severe hypoglycaemia recorded [estimated IR 11.97 (95% confidence interval, CI, 11.11-12.90) per 10,000 person-years (PYs)]. The IR was markedly higher in insulin users [49.64 (95% CI, 44.08-55.89) per 10,000 PYs] than in patients not using insulin [8.03 (95% CI, 7.30-8.84) per 10,000 PYs]. Based on results of the nested case-control analysis increasing age [≥ 75 vs. 20-59 years; adjusted odds ratio (OR), 2.27; 95% CI, 1.65-3.12], cognitive impairment/dementia (adjusted OR, 2.00; 95% CI, 1.37-2.91), renal failure (adjusted OR, 1.34; 95% CI, 1.04-1.71), current use of sulphonylureas (adjusted OR, 4.45; 95% CI, 3.53-5.60) and current insulin use (adjusted OR, 11.83; 95% CI, 9.00-15.54) were all associated with an increased risk of severe hypoglycaemia. CONCLUSIONS Severe hypoglycaemia was recorded in 12 cases per 10,000 PYs. Risk factors for severe hypoglycaemia included increasing age, renal failure, cognitive impairment/dementia, and current use of insulin or sulphonylureas.

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BACKGROUND Urinary incontinence or the inability to void spontaneously after ileal orthotopic bladder substitution is a frequent finding in female patients. OBJECTIVE To evaluate how hysterectomy and nerve sparing affect functional outcomes and whether these relate to pre- and postoperative urethral pressure profile (UPP) results. DESIGN, SETTING, AND PARTICIPANTS Prospectively performed pre- and postoperative UPPs of 73 female patients who had undergone cystectomy and bladder substitution were correlated with postoperative voiding and continence status. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Outcome analyses were performed with the Kruskal-Wallis test, Wilcoxon-Mann-Whitney, or two-group post hoc testing with the Bonferroni correction. Chi-square or Fisher exact tests were applied for the categorical data. RESULTS AND LIMITATIONS Of postoperatively continent or hypercontinent patients, 22 of 43 (51.2%) had the uterus preserved; of incontinent patients, only 4 of 30 (13.3%, p<0.01) had the uterus preserved. Of postoperatively continent or hypercontinent patients, 27 of 43 patients (62.8%) had bilateral and 15 of 43 (34.9%) had unilateral attempted nerve sparing. In incontinent patients, 11 of 30 (36.7%) had bilateral and 16 of 30 (53.3%) had unilateral attempted nerve sparing (p=0.02). When compared with postoperatively incontinent patients, postoperatively continent patients had a longer functional urethral length (median: 32mm vs 24mm; p<0.001), a higher postoperative urethral closing pressure at rest (56cm H2O vs 35cm H2O; p<0.001) as well as a higher preoperative urethral closing pressure at rest (74cm H2O vs 47.5cm H2O; p=0.01). The main limitation was the limited number of patients. CONCLUSIONS In female patients undergoing radical cystectomy and bladder substitution, preservation of the uterus and attempted nerve sparing results in better functional outcomes. The preoperative UPPs correlate with postoperative voiding and continence status and may predict which patients are at a higher risk of functional failure after bladder substitution. PATIENT SUMMARY If preservation of the urethra's innervation is not possible during cystectomy, poor functional results with bladder substitutes are likely.

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BACKGROUND In the meantime, catheter ablation is widely used for the treatment of persistent atrial fibrillation (AF). There is a paucity of data about long-term outcomes. This study evaluates (1) 5-year single and multiple procedure success and (2) prognostic factors for arrhythmia recurrences after catheter ablation of persistent AF using the stepwise approach aiming at AF termination. METHODS AND RESULTS A total of 549 patients with persistent AF underwent de novo catheter ablation using the stepwise approach (2007-2009). A total of 493 patients were included (Holter ECGs ≥ every 6 months). Mean follow-up was 59 ± 16 months with 2.1 ± 1.1 procedures per patient. Single and multiple procedure success rates were 20.1% and 55.9%, respectively (80% off antiarrhythmic drug). Antiarrhythmic drug-free multiple procedure success was 46%. Long-term recurrences (n=171) were paroxysmal AF in 48 patients (28%) and persistent AF/atrial tachycardia in 123 patients (72%). Multivariable recurrent event analysis revealed the following factors favoring arrhythmia recurrence: failure to terminate AF during index procedure (hazard ratio [HR], 1.279; 95% confidence interval [CI], 1.093-1.497; P = 0.002), number of procedures (HR, 1.154; 95% CI, 1.051-1.267; P = 0.003), female sex (HR, 1.263; 95% CI, 1.027-1.553; P = 0.027), and the presence of structural heart disease (HR, 1.236; 95% CI, 1.003-1.524; P = 0.047). AF termination was correlated with a higher rate of consecutive procedures because of atrial tachycardia recurrences (P = 0.003; HR, 1.71; 95% CI, 1.20-2.43). CONCLUSIONS Catheter ablation of persistent AF using the stepwise approach provides limited long-term freedom of arrhythmias often requiring multiple procedures. AF termination, the number of procedures, sex, and the presence of structural heart disease correlate with outcome success. AF termination is associated with consecutive atrial tachycardia procedures.

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PURPOSE The aim of this study was to analyze the patient pool referred to a specialty clinic for implant surgery over a 3-year period. MATERIALS AND METHODS All patients receiving dental implants between 2008 and 2010 at the Department of Oral Surgery and Stomatology were included in the study. As primary outcome parameters, the patients were analyzed according to the following criteria: age, sex, systemic diseases, and indication for therapy. For the inserted implants, the type of surgical procedure, the types of implants placed, postsurgical complications, and early failures were recorded. A logistic regression analysis was performed to identify possible local and systemic risk factors for complications. As a secondary outcome, data regarding demographics and surgical procedures were compared with the findings of a historic study group (2002 to 2004). RESULTS A total of 1,568 patients (792 women and 776 men; mean age, 52.6 years) received 2,279 implants. The most frequent indication was a single-tooth gap (52.8%). Augmentative procedures were performed in 60% of the cases. Tissue-level implants (72.1%) were more frequently used than bone-level implants (27.9%). Regarding dimensions of the implants, a diameter of 4.1 mm (59.7%) and a length of 10 mm (55.0%) were most often utilized. An early failure rate of 0.6% was recorded (13 implants). Patients were older and received more implants in the maxilla, and the complexity of surgical interventions had increased when compared to the patient pool of 2002 to 2004. CONCLUSION Implant therapy performed in a surgical specialty clinic utilizing strict patient selection and evidence-based surgical protocols showed a very low early failure rate of 0.6%.

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The study of secession generally stresses the causal influence of cultural identities, political preferences, or ecological factors. Whereas these different views are often considered to be mutually exclusive, this paper proposes a two-stage model in which they are complementary. We posit that cultural identities matter for explaining secessionism, but not because of primordial attachments. Rather, religious and linguistic groups matter because their members are imbued with cultural legacies that lead to distinct political preferences – in this case preferences over welfare statism. Further, ecological constraints such as geography and topography affect social interaction with like-minded individuals. On the basis of both these political preferences and ecological constraints, individuals then make rational choices about the desirability of secession. Instrumental considerations are therefore crucial in explaining the decision to secede, but not in a conventional pocketbook manner. To examine this theory, we analyze the 2013 referendum on the secession of the Jura Bernois region from the Canton of Berne in Switzerland, using municipal level census and referendum data. The results lend support to the theory and suggest one way in which the politics of identity, based on factors like language and religion, can be fused with the politics of interest (preferences for more or less state intervention into the polity and economy) to better understand group behavior.

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Analysis of recurrent events has been widely discussed in medical, health services, insurance, and engineering areas in recent years. This research proposes to use a nonhomogeneous Yule process with the proportional intensity assumption to model the hazard function on recurrent events data and the associated risk factors. This method assumes that repeated events occur for each individual, with given covariates, according to a nonhomogeneous Yule process with intensity function λx(t) = λ 0(t) · exp( x′β). One of the advantages of using a non-homogeneous Yule process for recurrent events is that it assumes that the recurrent rate is proportional to the number of events that occur up to time t. Maximum likelihood estimation is used to provide estimates of the parameters in the model, and a generalized scoring iterative procedure is applied in numerical computation. ^ Model comparisons between the proposed method and other existing recurrent models are addressed by simulation. One example concerning recurrent myocardial infarction events compared between two distinct populations, Mexican-American and Non-Hispanic Whites in the Corpus Christi Heart Project is examined. ^

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Context. Healthcare utilization of elder cardiovascular patients in United States will increase in near future, due to an aging population. This trend could burden urban emergency centers, which have become a source of primary care. ^ Objective. The objective of this study was to determine the association of age, gender, ethnicity, insurance and other presenting variables on hospital admission in an emergency center for elder cardiovascular patients. ^ Design, setting and participants. An anonymous retrospective review of emergency center patient login records of an urban emergency center in the years 2004 and 2005 was conducted. Elder patients (age ≥ 65 years) with cardiovascular disease (ICD91 390-459) were included. Multivariate logistic regression analysis was used to identify independent factors for hospital admission. Four major cardiovascular reasons for hospitalisation – ischemic heart disease, heart failure, hypertensive disorders and stroke were analysed separately. ^ Results. The number of elder patients in the emergency center is increasing, the most common reason for their visit was hypertension. Majority (59%) of the 12,306 elder patients were female. Forty five percent were uninsured and 1,973 patients had cardiovascular disease. Older age (OR 1.10; CI 1.02-1.19) was associated with a marginal increase in hospital admission in elder stroke patients. Elder females compared to elder males were more likely to be hospitalised for ischemic heart disease (OR 2.71; CI 1.22-6.00) and heart failure (OR 1.58; CI 1.001-2.52). Furthermore, insured elder heart failure patients (OR 0.54; CI 0.31-0.93) and elder African American heart failure patients (OR 0.32; CI 0.13-0.75) were less likely to be hospitalised. Ambulance use was associated with greater hospital admissions in elder cardiovascular patients studied, except for stroke. ^ Conclusion. Appropriate health care distribution policies are needed for elder patients, particularly elder females, uninsured, and racial/ethnic minorities. These findings could help triage nurse evaluations in emergency centers to identify patients who were more likely to be hospitalised to offer urgent care and schedule appointments in primary care clinics. In addition, health care plans could be formulated to improve elder primary care, decrease overcrowding in emergency centers, and decrease elder healthcare costs in the future. ^

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Objectives. Predict who will develop a dissection. To create male and female prediction models using the risk factors: age, ethnicity, hypertension, high cholesterol, smoking, alcohol use, diabetes, heart attack, congestive heart failure, congenital and non-congenital heart disease, Marfan syndrome, and bicuspid aortic valve. ^ Methods. Using 572 patients diagnosed with aortic aneurysms, a model was developed for each of males and females using 80% of the data and then verified using the remaining 20% of the data. ^ Results. The male model predicted the probability of a male in having a dissection (p=0.076) and the female model predicted the probability of a female in having a dissection (p=0.054). The validation models did not support the choice of the developmental models. ^ Conclusions. The best models obtained suggested that those who are at a greater risk of having a dissection are males with non-congenital heart disease and who drink alcohol, and females with non-congenital heart disease and bicuspid aortic valve.^

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Genital human papillomavirus (HPV) is of public health concern because persistent infection with certain HPV types can cause cervical cancer. In response to a nationwide push for cervical cancer legislation, Texas Governor Rick Perry bypassed the traditional legislative process and issued an executive order mandating compulsory HPV vaccinations for all female public school students prior to their entrance in the sixth grade. By bypassing the legislative process Governor Perry did not effectively mitigate the risk perception issues that arose around the need for and usefulness of the vaccine mandate. This policy paper uses a social policy paradigm to identify perception as the key intervening factor on how the public responds to risk information. To demonstrate how the HPV mandate failed, it analyzes four factors, economics, politics, knowledge and culture, that shape perception and influence the public's response. By understanding the factors that influence the public's perception, public health practitioners and policy makers can more effectively create preventive health policy at the state level. ^

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RAS-ERK-MAPK (Mitogen-activated protein kinase) pathway plays an essential role in proliferation, differentiation, and tumor progression. In this study, we showed that ERK downregulated FOXO3a through directly interacting with and phosphorylating FOXO3a at Serine 294, Serine 344, and Serine 425. ERK-phosphorylated FOXO3a was degraded by MDM2-mediated ubiquitin-proteosome pathway. FOXO3a phosphorylation and degradation consequently promoted cell proliferation and tumorigenesis. However, the non-phosphorylated FOXO3a mutant, which was resistant to the interaction and degradation by MDM2, resulted in inhibition of tumor formation. Forkhead O transcription factors (FOXOs) are important in the regulation of cellular functions including cell cycle arrest and cell death. Perturbation of FOXOs function leads to deregulated cell proliferation and cancer. Inactivation of FOXO proteins by activation of cell survival pathways, such as PI3K/AKT/IKK, is associated with tumorigenesis. Our study will further highlight FOXOs as new therapeutic targets in a broad spectrum of cancers. ^ Chemotherapeutic drug resistance is the most concerned problem in cancer therapy as resistance ultimately leads to treatment failure of cancer patients. In another study, we showed that blocking ERK activity with AZD6244, an established MEK1/2 inhibitor currently under human cancer clinical trials, enhances FOXO3a expression in various human cancer cell lines in vitro, and also in human colon cancer cell xenografts in vivo. Knocking down FOXO3a and its downstream gene Bim impaired AZD6244-induced growth suppression, whereas restoring activation of FOXO3a sensitized human cancer cell to AZD6244-induced growth arrest and apoptosis. More importantly, AZD6244-resistant cancer cells showed impaired endogenous FOXO3a nuclear translocation, reduced FOXO3a-Bim promoter association and significantly decreased Bim expression in response to AZD6244. AZD6244-resistant cancer cells can be sensitized to API-2 (an AKT inhibitor) and LY294002 (a PI3K inhibitor) in suppressing cell growth and colony formation, these inhibitors were known to enhance FOXO3a activity/nuclear translocation through inhibiting PI3K-AKT pathway. This study reveals novel molecular mechanism contributing to AZD6244-resistance through regulation of FOXO3a activity, further provides significant clinical implication of combining AZD6244 with PI3K/AKT inhibitors for sensitizing AZD6244-resistant cancer cells by activating FOXO3a. FOXO3a activation can be an essential pharmacological target and indicator to mediate and predict AZD6244 efficacy in clinical use. ^

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Background. Polyomavirus reactivation is common in solid-organ transplant recipients who are given immunosuppressive medications as standard treatment of care. Previous studies have shown that polyomavirus infection can lead to allograft failure in as many as 45% of the affected patients. Hypothesis. Ubiquitous polyomaviruses when reactivated by post-transplant immunosuppressive medications may lead to impaired renal function and possibly lower survival prospects. Study Overview. Secondary analysis of data was conducted on a prospective longitudinal study of subjects who were at least 18 years of age and were recipients of liver and/or kidney transplant at Mayo Clinic Scottsdale, Arizona. Methods. DNA extractions of blinded urine and blood specimens of transplant patients collected at Mayo Clinic during routine transplant patient visits were performed at Baylor College of Medicine using Qiagen kits. Virologic assays included testing DNA samples for specific polyomavirus sequences using QPCR technology. De-identified demographic and clinical patient data were merged with laboratory data and statistical analysis was performed using Stata10. Results. 76 patients enrolled in the study were followed for 3.9 years post transplantation. The prevalence of BK virus and JC virus urinary excretion was 30% and 28%. Significant association was observed between JC virus excretion and kidney as the transplanted organ (P = 0.039, Pearson Chi-square test). The median urinary JCV viral loads were two logs higher than those of BKV. Patients that excreted both BKV and JCV appeared to have the worst renal function with a mean creatinine clearance value of 71.6 millimeters per minute. A survival disadvantage was observed for dual shedders of BKV and JCV, log-rank statistics, p = 0.09; 2/5 dual-shedders expired during the study period. Liver transplant and male sex were determined to be potential risk factors for JC virus activation in renal and liver transplant recipients. All patients tested negative for SV40 and no association was observed between polyomavirus excretion and type of immunosuppressive medication (tacrolimus, mycophenolate mofetil, cyclosporine and sirolimus). Conclusions. Polyomavirus reactivation was common after solid-organ transplantation and may be associated with impaired renal function. Male sex and JCV infection may be potential risk factors for viral reactivation; findings should be confirmed in larger studies.^