Renal artery assessment with nonenhanced steady-state free precession versus contrast-enhanced MR angiography

PURPOSE: To prospectively assess the diagnostic accuracy of nonenhanced three-dimensional (3D) steady-state free precession (SSFP) magnetic resonance (MR) angiography for detection of renal artery stenosis (RAS), with breath-hold contrast material-enhanced MR angiography performed as the reference standard. MATERIALS AND METHODS: The study was local ethics committee approved; all patients gave written informed consent. Fifty-three patients (30 male, 23 female; mean age, 58 years) with arterial hypertension and suspected of having RAS were examined with 1.5-T 3D SSFP renal MR angiography. Stenosis grade, maximal visible vessel length, and subjective image quality were compared. Sensitivity, specificity, accuracy, and negative predictive value (NPV) were calculated on artery-by-artery and patient-by-patient bases. The significance of the results was assessed with the paired two-sided t test for continuous variables and with the marginal homogeneity test for categorical variables. Cohen kappa statistics were used to estimate interobserver agreement. RESULTS: One hundred eight renal arteries with 20 significant (>or=50%) stenoses were detected with contrast-enhanced MR angiography. At artery-by-artery analysis, sensitivity, specificity, accuracy, and NPV of nonenhanced SSFP MR angiography for RAS detection were 100%, 93%, 94%, and 100%, respectively, for observer 1 and 95%, 95%, 95%, and 99%, respectively, for observer 2. Corresponding patient-by-patient values were 100%, 92%, 94%, and 100%, respectively, for observer 1 and 100%, 95%, 96%, and 100%, respectively, for observer 2. Overestimation of stenosis grade with SSFP MR angiography resulted in six and four false-positive findings for readers 1 and 2, respectively. Mean maximal visible lengths of the renal arteries were 69.9 mm at contrast-enhanced MR angiography and 61.1 mm at SSFP MR angiography (P<.001). Both techniques yielded good to excellent image quality. CONCLUSION: Slab-selective inversion-prepared 3D SSFP MR angiography had high sensitivity, specificity, accuracy, and NPV for RAS detection, without the need for contrast material. However, RAS severity was overestimated in some patients.

Self-reported non-adherence to antiretroviral therapy repeatedly assessed by two questions predicts treatment failure in virologically suppressed patients

BACKGROUND: The aim of this study was to explore the predictive value of longitudinal self-reported adherence data on viral rebound. METHODS: Individuals in the Swiss HIV Cohort Study on combined antiretroviral therapy (cART) with RNA <50 copies/ml over the previous 3 months and who were interviewed about adherence at least once prior to 1 March 2007 were eligible. Adherence was defined in terms of missed doses of cART (0, 1, 2 or >2) in the previous 28 days. Viral rebound was defined as RNA >500 copies/ml. Cox regression models with time-independent and -dependent covariates were used to evaluate time to viral rebound. RESULTS: A total of 2,664 individuals and 15,530 visits were included. Across all visits, missing doses were reported as follows: 1 dose 14.7%, 2 doses 5.1%, >2 doses 3.8% taking <95% of doses 4.5% and missing > or =2 consecutive doses 3.2%. In total, 308 (11.6%) patients experienced viral rebound. After controlling for confounding variables, self-reported non-adherence remained significantly associated with the rate of occurrence of viral rebound (compared with zero missed doses: 1 dose, hazard ratio [HR] 1.03, 95% confidence interval [CI] 0.72-1.48; 2 doses, HR 2.17, 95% CI 1.46-3.25; >2 doses, HR 3.66, 95% CI 2.50-5.34). Several variables significantly associated with an increased risk of viral rebound irrespective of adherence were identified: being on a protease inhibitor or triple nucleoside regimen (compared with a non-nucleoside reverse transcriptase inhibitor), >5 previous cART regimens, seeing a less-experienced physician, taking co-medication, and a shorter time virally suppressed. CONCLUSIONS: A simple self-report adherence questionnaire repeatedly administered provides a sensitive measure of non-adherence that predicts viral rebound.

Strategies for routine biopsies in heart transplantation based on 8-year results with more than 13,000 biopsies

The endomyocardial biopsy (EMB) in heart transplant recipients has been considered the "gold standard" for diagnosis of graft rejection (REJ). The purpose of this retrospective study is to develop long-term strategies (frequency and postoperative duration of EMB) for REJ monitoring. Between 1985 and 1992, 346 patients (mean age 44.5 years, female patients = 14%) received 382 heart grafts. For graft surveillance EMBs were performed according to a fixed schedule depending on postoperative day and the results of previous biopsies. In the first year the average number (no.) of EMBs/patient was 20 with 19% positive for REJ in the first quarter, dropping to 7% REJ/EMB by the end of the first year. The percentage of REJ/EMB declined annually from 4.7% to 4.5%, 2.2% and less than 1% after the fifth year. Individual biopsy results in the first 3 postoperative months had little predictive value. Patients with fewer than two REJ (group 1), vs patients with two or more REJ in the first 6 postoperative months (group 2), were significantly less likely to reject in the second half of the first year (group 1: 0.29 +/- 0.6 REJ/patient; group 2:0.83 +/- 1.3 REJ/patient; P < 0.001) and third postoperative year (group 1:0.12 +/- 0.33 REJ/patients; group 2:0.46 +/- 0.93 REJ/patient; P < 0.05). In conclusion, routine EMBs in the first 3 postoperative months have only limited predictive value, however the number of routine EMBs can be drastically reduced later depending on the intermediate postoperative REJ pattern.

Accuracy of WHO CD4 cell count criteria for virological failure of antiretroviral therapy

OBJECTIVES: To examine the accuracy of the World Health Organization immunological criteria for virological failure of antiretroviral treatment. METHODS: Analysis of 10 treatment programmes in Africa and South America that monitor both CD4 cell counts and HIV-1 viral load. Adult patients with at least two CD4 counts and viral load measurements between month 6 and 18 after starting a non-nucleoside reverse transcriptase inhibitor-based regimen were included. WHO immunological criteria include CD4 counts persistently <100 cells/microl, a fall below the baseline CD4 count, or a fall of >50% from the peak value. Virological failure was defined as two measurements > or =10 0000 copies/ml (higher threshold) or > or =500 copies/ml (lower threshold). Measures of accuracy with exact binomial 95% confidence intervals (CI) were calculated. RESULTS: A total of 2009 patients were included. During 1856 person-years of follow up 63 patients met the immunological criteria and 35 patients (higher threshold) and 95 patients (lower threshold) met the virological criteria. Sensitivity [95% confidence interval (CI)] was 17.1% (6.6-33.6%) for the higher and 12.6% (6.7-21.0%) for the lower threshold. Corresponding results for specificity were 97.1% (96.3-97.8%) and 97.3% (96.5-98.0%), for positive predictive value 9.5% (3.6-19.6%) and 19.0% (10.2-30.9%) and for negative predictive value 98.5% (97.9-99.0%) and 95.7% (94.7-96.6%). CONCLUSIONS: The positive predictive value of the WHO immunological criteria for virological failure of antiretroviral treatment in resource-limited settings is poor, but the negative predictive value is high. Immunological criteria are more appropriate for ruling out than for ruling in virological failure in resource-limited settings.

Heart rate response determines long term exercise capacity after heart transplantation

BACKGROUND: Exercise capacity after heart transplantation (HTx) remains limited despite normal left ventricular systolic function of the allograft. Various clinical and haemodynamic parameters are predictive of exercise capacity following HTx. However, the predictive significance of chronotropic competence has not been demonstrated unequivocally despite its immediate relevance for cardiac output. AIMS: This study assesses the predictive value of various clinical and haemodynamic parameters for exercise capacity in HTx recipients with complete chronotropic competence evolving within the first 6 postoperative months. METHODS: 51 patients were enrolled in this exercise study. Patients were included when at least >6 months after HTx and without negative chronotropic medication or factors limiting exercise capacity such as significant transplant vasculopathy or allograft rejection. Clinical parameters were obtained by chart review, haemodynamic parameters from current cardiac catheterisation, and exercise capacity was assessed by treadmill stress testing. A stepwise multiple regression model analysed the proportion of the variance explained by the predictive parameters. RESULTS: The mean age of these 51 HTx recipients was 55.4 +/- 13.2 yrs on inclusion, 42 pts were male and the mean time interval after cardiac transplantation was 5.1 +/- 2.8 yrs. Five independent predictors explained 47.5% of the variance observed for peak exercise capacity (adjusted R2 = 0.475). In detail, heart rate response explained 31.6%, male gender 5.2%, age 4.1%, pulmonary vascular resistance 3.7%, and body-mass index 2.9%. CONCLUSION: Heart rate response is one of the most important predictors of exercise capacity in HTx recipients with complete chronotropic competence and without relevant transplant vasculopathy or acute allograft rejection.

Relationship between renal resistance index and renal function in liver transplant recipients after cessation of calcineurin inhibitor

End stage renal disease is a major complication after orthotopic liver transplantation (OLT). Vasoconstriction of renal arterial vessels because of calcineurin inhibitor (CNI) treatment plays a pivotal role in the development of renal insufficiency following OLT. Renal resistance can be measured non-invasively by determining the resistance index (RI) of segmental arteries by color-coded duplex ultrasonography, a measure with predictive value for future renal failure. Sixteen OLT patients on long-term CNI therapy were recruited prospectively and randomly assigned either to receive the m-TOR inhibitor sirolimus (SRL) or to continue on CNI treatment, and were followed for one yr. Serum creatinine (crea) declined after conversion to SRL, whereas it tended to increase in patients remaining on CNI (meanDelta crea SRL: -27, -18, -18, -15 micromol/L; meanDelta crea CNI: 4, 5, 8, 11 micromol/L at 1, 3, 6, 12 months, p = 0.02). RI improved after switching to SRL and was lower on SRL than on CNI (meanDeltaRI SRL: -0.04, -0.04, -0.03, -0.03; meanDeltaRI CNI: -0.006, 0.004, -0.007, -0.01 after 1, 3, 6, 12 months, p = 0.016). Individual changes of RI correlated significantly with individual changes of crea (r = 0.54, p < 0.001). Conversion from CNI to SRL can ameliorate renal function accompanied by a reduction of intrarenal RI after OLT.

Association between longitudinal changes in depressive symptoms and plasma fibrinogen levels in school teachers

Depression and anxiety previously predicted coronary artery disease (CAD) risk. Inflammation contributes to CAD and shows an association with depression. We followed 57 teachers (mean 49+/-8 years) over 21 months and investigated whether changes in depressive and anxiety symptoms relate to those in the CAD risk and inflammation marker fibrinogen and vice versa. Increase in depressive symptoms and in fibrinogen levels were significantly correlated. While controlling for baseline depression rendered the association between changes in depression and fibrinogen nonsignificant, taking into account baseline fibrinogen levels maintained the predictive value of fibrinogen change for depression change. Anxiety and fibrinogen changes were not significantly correlated. This dynamic relationship between depression and the inflammatory biomarker fibrinogen might advance our knowledge about psychobiological mechanisms underlying both CAD and sickness behavior.

One-year evaluation of a neonatal screening program for cystic fibrosis in Switzerland

BACKGROUND From January 2011 onward, the Swiss newborn screening (NBS) program has included a test for cystic fibrosis (CF). In this study, we evaluate the first year of implementation of the CF-NBS program. METHODS The CF-NBS program consists of testing in two steps: a heel prick sample is drawn (= Guthrie test) for measurement of immunoreactive trypsinogen (IRT) and for DNA screening. All children with a positive screening test are referred to a CF center for further diagnostic testing (sweat test and genetic analysis). After assessment in the CF center, the parents are given a questionnaire. All the results of the screening process and the parent questionnaires were centrally collected and evaluated. RESULTS In 2011, 83 198 neonates were screened, 84 of whom (0.1%) had a positive screening result and were referred to a CF center. 30 of these 84 infants were finally diagnosed with CF (positive predictive value: 35.7%). There was an additional infant with CF and meconium ileus whose IRT value was normal. The 31 diagnosed children with CF correspond to an incidence of 1 : 2683. The average time from birth to genetically confirmed diagnosis was 34 days (range: 13-135). 91% of the parents were satisfied that their child had undergone screening. All infants receiving a diagnosis of CF went on to receive further professional care in a CF center. CONCLUSION The suggested procedure for CF-NBS has been found effective in practice; there were no major problems with its implementation. It reached high acceptance among physicians and parents.

Electrocardiographic characteristics of patients with Ebstein's anomaly before and after ablation of an accessory atrioventricular pathway

UNLABELLED The abnormal development of the tricuspid valve in patients with Ebstein's anomaly results in several activation abnormalities including delayed intraatrial conduction, right bundle branch block (RBBB), and ventricular preexcitation. The aim of the present study was to define the ECG characteristics before and after ablation of an accessory A-V pathway (AP) in patients with Ebstein's anomaly. METHODS A series of 226 consecutive patients with Ebstein's anomaly was studied. Sixty-four patients (28%) had documented tachycardia. Thirty-three patients with recurrent tachycardia were found to have a single right-sided AP that was successfully ablated (study group). Thirty patients without tachycardia served as the control group. RESULTS Only 21 of 33 patients (62%) had a typical ECG pattern of preexcitation. In addition, none of the patients had an ECG pattern of RBBB during sinus rhythm. In contrast, 28 of 30 (93%) patients in the control group had RBBB (P < 0.001). Radiofrequency catheter ablation resulted in appearance of RBBB in 31 of 33 (94%) patients. The absence of RBBB in patients with Ebstein's anomaly and recurrent tachycardia had a 98% sensitivity and 92% specificity for the diagnosis of an AP. The positive predictive value was 91% (0.77, 0.97 CI 95%) and the negative predictive value was 98% (0.85, 0.99 CI 95%). CONCLUSION One-third of patients with Ebstein's anomaly and symptomatic tachyarrhythmias have minimal or absent ECG features of ventricular preexcitation. In these patients, the absence of RBBB pattern is a strong predictor of an AP.

Executive functions in 5- to 8-year olds: Developmental changes and relationship to academic achievement

Pronounced improvements in executive functions (EF) during preschool years have been documented in cross-sectional studies. However, longitudinal evidence on EF development during the transition to school and predictive associations between early EF and later school achievement are still scarce. This study examined developmental changes in EF across three time-points, the predictive value of EF for mathematical, reading and spelling skills and explored children's specific academic attainment as a function of early EF. Participants were 323 children following regular education; 160 children were enrolled in prekindergarten (younger cohort: 69 months) and 163 children in kindergarten (older cohort: 78.4 months) at the first assessment. Various tasks of EF were administered three times with an interval of one year each. Mathematical, reading and spelling skills were measured at the last assessment. Individual background characteristics such as vocabulary, non-verbal intelligence and socioeconomic status were included as control variables. In both cohorts, changes in EF were substantial; improvements in EF, however, were larger in preschoolers than school-aged children. EF assessed in preschool accounted for substantial variability in mathematical, reading and spelling achievement two years later, with low EF being especially associated with significant academic disadvantages in early school years. Given that EF continue to develop from preschool into primary school years and that starting with low EF is associated with lower school achievement, EF may be considered as a marker or risk for academic disabilities.

Interim endoscopy results during neoadjuvant therapy for gastric cancer correlate with histopathological response and prognosis

BACKGROUND Neoadjuvant chemotherapy for locally advanced gastric cancer leads to major histopathological response in less than 30 % of patients. Data on interim endoscopic response assessment do not exist. This exploratory prospective study evaluates early endoscopy after 50 % of the chemotherapy as predictor for later response and prognosis. METHODS Forty-seven consecutive patients were included (45 resected; 33 R0 resections). All patients received baseline endoscopy and CT scans, after 50 % of their chemotherapy (EGD-1, CT-1) and after completion of chemotherapy (EGD-2, CT-2). Interim endoscopic response (EGD-1) was assessed after having received 50 % (6 weeks) of the planned 12 weeks of neoadjuvant chemotherapy. Post-chemotherapy response was clinically assessed by a combination of CT scan (CT-2) and endoscopy (EGD-2). Histopathological response was determined by a standardized scoring system (Becker criteria). Endoscopic response was defined as a reduction of >75 % of the tumor mass. RESULTS Twelve patients were responders at EGD-1 and 13 at EGD-2. Nine patients (19.1 %) were clinical responders and 7 patients (15.6 %) were histopathological responders after chemotherapy. Specificity, accuracy, and negative predictive value of the interim EGD-1 for subsequent histopathological response were 31/38 (82 %), 36/47 (76 %), and 31/33 (93 %); and for recurrence or death, 28/30 (93.3 %), 38/47 (80.9 %), and 28/35 (80.0 %). Response at EGD-1 was significantly associated with histopathological response (p = 0.010), survival (p < 0.001), and recurrence-free survival (p = 0.009). CONCLUSIONS Interim endoscopy after 6 weeks predicts response and prognosis. Therefore, tailoring treatment according to interim endoscopic assessment could be feasible, but the findings of this study should be validated in a larger patient cohort.

Loss of Cdx2 Expression in Primary Tumors and Lymph Node Metastases is Specific for Mismatch Repair-Deficiency in Colorectal Cancer

Background: Approximately 20% of all colorectal cancers are hypothesized to arise from the "serrated pathway" characterized by mutation in BRAF, high-level CpG Island Methylator Phenotype, and microsatellite instability/mismatch repair (MMR)-deficiency. MMR-deficient cancers show frequent losses of Cdx2, a homeodomain transcription factor. Here, we determine the predictive value of Cdx2 expression for MMR-deficiency and investigate changes in expression between primary cancers and matched lymph node metastases. Methods: Immunohistochemistry for Cdx2, Mlh1, Msh2, Msh6, and Pms2 was performed on whole tissue sections from 201 patients with primary colorectal cancer and 59 cases of matched lymph node metastases. Receiver operating characteristic curve analysis and Area under the Curve (AUC) were investigated; association of Cdx2 with clinicopathological features and patient survival was carried out. Results: Loss of Cdx2 expression was associated with higher tumor grade (p = 0.0002), advanced pT (p = 0.0166), and perineural invasion (p = 0.0228). Cdx2 loss was an unfavorable prognostic factor in univariate (p = 0.0145) and multivariate [p = 0.0427; HR (95% CI): 0.58 (0.34-0.98)] analysis. The accuracy (AUC) for discriminating MMR-proficient and - deficient cancers was 87% [OR (95% CI): 0.96 (0.95-0.98); p < 0.0001]. Specificity and negative predictive value for MMR-deficiency was 99.1 and 96.3%. One hundred and seventy-four patients had MMR-proficient cancers, of which 60 (34.5%) showed Cdx2 loss. Cdx2 loss in metastases was related to MMR-deficiency (p < 0.0001). There was no difference in expression between primary tumors and matched metastases. Conclusion: Loss of Cdx2 is a sensitive and specific predictor of MMR-deficiency, but is not limited to these tumors, suggesting that events "upstream" of the development of microsatellite instability may impact Cdx2 expression.

Tumor regression grade of urothelial bladder cancer after neoadjuvant chemotherapy: a novel and successful strategy to predict survival.

Histopathologic tumor regression grades (TRGs) after neoadjuvant chemotherapy predict survival in different cancers. In bladder cancer, corresponding studies have not been conducted. Fifty-six patients with advanced invasive urothelial bladder cancer received neoadjuvant chemotherapy before cystectomy and lymphadenectomy. TRGs were defined as follows: TRG1: complete tumor regression; TRG2: >50% tumor regression; TRG3: 50% or less tumor regression. Separate TRGs were assigned for primary tumors and corresponding lymph nodes. The prognostic impact of these 2 TRGs, the highest (dominant) TRG per patient, and competing tumor features reflecting tumor regression (ypT/ypN stage, maximum diameter of the residual tumor) were determined. Tumor characteristics in initial transurethral resection of the bladder specimens were tested for response prediction. The frequency of TRGs 1, 2, and 3 in the primary tumors were n=16, n=19, and n=21; corresponding data from the lymph nodes were n=31, n=9, and n=16. Interobserver agreement in determination of the TRG was strong (κ=0.8). Univariately, all evaluated parameters were significantly (P≤0.001) related to overall survival; however, the segregation of the Kaplan-Meier curves was best for the dominant TRG. In multivariate analysis, only dominant TRG predicted overall survival independently (P=0.035). In transurethral resection specimens of the chemotherapy-naive bladder cancer, the only tumor feature with significant (P<0.03) predictive value for therapy response was a high proliferation rate. In conclusion, among all parameters reflecting tumor regression, the dominant TRG was the only independent risk factor. A favorable chemotherapy response is associated with a high proliferation rate in the initial chemotherapy-naive bladder cancer. This feature might help personalize neoadjuvant chemotherapy.

Prediction of outcome in patients with low-grade squamous intraepithelial lesions by fluorescence in situ hybridization analysis of human papillomavirus, TERC, and MYC

BACKGROUND Cytology is an excellent method with which to diagnose preinvasive lesions of the uterine cervix, but it suffers from limited specificity for clinically significant lesions. Supplementary methods might predict the natural course of the detected lesions. The objective of the current study was to test whether a multicolor fluorescence in situ hybridization (FISH) assay might help to stratify abnormal results of Papanicolaou tests. METHODS A total of 219 liquid-based cytology specimens of low-grade squamous intraepithelial lesions (LSIL), 49 atypical squamous cells of undetermined significance (ASCUS) specimens, 52 high-grade squamous intraepithelial lesion (HSIL) specimens, and 50 normal samples were assessed by FISH with probes for the human papillomavirus (HPV), MYC, and telomerase RNA component (TERC). Subtyping of HPV by polymerase chain reaction (PCR) was performed in a subset of cases (n=206). RESULTS There was a significant correlation found between HPV detection by FISH and PCR (P<.0001). In patients with LSILs, the presence of HPV detected by FISH was significantly associated with disease progression (P<.0001). An increased MYC and/or TERC gene copy number (>2 signals in>10% of cells) prevailed in 43% of ASCUS specimens and was more frequent in HSIL (85%) than in LSIL (33%) (HSIL vs LSIL: P<.0001). Increased TERC gene copy number was significantly correlated with progression of LSIL (P<.01; odds ratio, 7.44; area under the receiver operating characteristic curve, 0.73; positive predictive value, 0.30; negative predictive value, 0.94) CONCLUSIONS: The detection of HPV by FISH analysis is feasible in liquid-based cytology and is significantly correlated with HPV analysis by PCR. The analysis of TERC gene copy number may be useful for risk stratification in patients with LSIL.

Empirical chemosensitivity testing in a spheroid model of ovarian cancer using a microfluidics-based multiplex platform.

The use of biomarkers to infer drug response in patients is being actively pursued, yet significant challenges with this approach, including the complicated interconnection of pathways, have limited its application. Direct empirical testing of tumor sensitivity would arguably provide a more reliable predictive value, although it has garnered little attention largely due to the technical difficulties associated with this approach. We hypothesize that the application of recently developed microtechnologies, coupled to more complex 3-dimensional cell cultures, could provide a model to address some of these issues. As a proof of concept, we developed a microfluidic device where spheroids of the serous epithelial ovarian cancer cell line TOV112D are entrapped and assayed for their chemoresponse to carboplatin and paclitaxel, two therapeutic agents routinely used for the treatment of ovarian cancer. In order to index the chemoresponse, we analyzed the spatiotemporal evolution of the mortality fraction, as judged by vital dyes and confocal microscopy, within spheroids subjected to different drug concentrations and treatment durations inside the microfluidic device. To reflect microenvironment effects, we tested the effect of exogenous extracellular matrix and serum supplementation during spheroid formation on their chemotherapeutic response. Spheroids displayed augmented chemoresistance in comparison to monolayer culturing. This resistance was further increased by the simultaneous presence of both extracellular matrix and high serum concentration during spheroid formation. Following exposure to chemotherapeutics, cell death profiles were not uniform throughout the spheroid. The highest cell death fraction was found at the center of the spheroid and the lowest at the periphery. Collectively, the results demonstrate the validity of the approach, and provide the basis for further investigation of chemotherapeutic responses in ovarian cancer using microfluidics technology. In the future, such microdevices could provide the framework to assay drug sensitivity in a timeframe suitable for clinical decision making.