Tuberculosis screening during the 2015 European refugee crisis.

BACKGROUND: The purpose of our study was to describe and evaluate management, performance and results of Tuberculosis (TB)-screening among refugees and asylum seekers in a rural area in Germany in 2015. METHODS: Refugees or asylum seekers, staying in shared-accommodation are obligated to participate on screening chest X-ray (CXR) in order to screen for signs of potentially infectious pulmonary TB (German Protection against Infection Act and German Asylum Procedure Act). n = 705 individuals underwent screening chest X-ray (CXR) to detect pulmonary TB in September and October 2015 on site. One experienced radiologist interpreted and reported each CXR within 24 h after the enrollment in the screening program and results were sent to the local Public Health Department for potential further medical care. Image abnormalities suggestive for TB were defined according to established radiographic criteria such as pleural effusion, cavitation, consolidation, fibrous scarring or calcification. Only in case of TB-suggestive findings on CXR, further diagnostics were arranged (pulmonological examination, follow-up CXR, sputum culture, interferon-gamma release assay, bronchoscopy). Follow-up data was collected in collaboration with the local Public Health Department. Descriptive statistics were calculated using GraphPad Prism software. RESULTS: n = 637 CXR examinations (90%) did not show abnormal findings, n = 54 CXR (8%) showed incidental findings, and n = 14 CXR (2%) were suspicious for acute TB. Of these, n = 14 individuals, eight underwent further TB diagnostics. Active TB was confirmed in one individual (0.001% of the screening cohort). CONCLUSIONS: Our cohort reflects current immigrations statistics in Europe and illustrates an overall low TB prevalence amongst individuals entering Germany in 2015. However, our findings support the improvement of diagnostic algorithms.

Renal ischemia-reperfusion injury causes hypertension and renal perfusion impairment in the CD1 mice which promotes progressive renal fibrosis.

Renal ischemia-reperfusion injury (IRI) is a severe complication of major surgery and a risk factor for increased morbidity and mortality. Here, we investigated mechanisms that might contribute to IRI-induced progression to chronic kidney disease (CKD). Acute kidney injury (AKI) was induced by unilateral IRI for 35 min in CD1 and C57BL/6 (B6) mice. Unilateral IRI was used to overcome early mortality. Renal morphology, NGAL upregulation, and neutrophil infiltration as well as peritubular capillary density were studied by immunohistochemistry. The composition of leukocyte infiltrates in the kidney after IRI was investigated by flow cytometry. Systemic blood pressure was measured with a tail cuff, and renal perfusion was quantified by functional magnetic resonance imaging (fMRI). Mesangial matrix expansion was assessed by silver staining. Following IRI, CD1 and B6 mice developed similar morphological signs of AKI and increases in NGAL expression, but neutrophil infiltration was greater in CD1 than B6 mice. IRI induced an increase in systemic blood pressure of 20 mmHg in CD1, but not in B6 mice; and CD1 mice also had a greater loss of renal perfusion and kidney volume than B6 mice ( P < 0.05). CD1 mice developed substantial interstitial fibrosis and decreased peritubular capillary (PTC) density by day 14 while B6 mice showed only mild renal scarring and almost normal PTC. Our results show that after IRI, CD1 mice develop more inflammation, hypertension, and later mesangial matrix expansion than B6 mice do. Subsequently, CD1 animals suffer from CKD due to impaired renal perfusion and pronounced permanent loss of peritubular capillaries.

Assessment of acute kidney injury with T1 mapping MRI following solid organ transplantation.

OBJECTIVES: To evaluate T1 mapping as a non-invasive, functional MRI biomarker in patients shortly after solid organ transplantation to detect acute postsurgical kidney damage and to correlate T1 times with renal function. METHODS: 101 patients within 2 weeks after solid organ transplantation (49 kidney transplantation, 52 lung transplantation) and 14 healthy volunteers were examined by MRI between July 2012 and April 2015 using the modified Look-Locker inversion recovery (MOLLI) sequence. T1 times in renal cortex and medulla and the corticomedullary difference were compared between groups using one-way ANOVA adjusted for multiple comparison with the Tukey test, and T1 times were correlated with renal function using Pearson's correlation. RESULTS: Compared to healthy volunteers T1 times were significantly increased after solid organ transplantation in the renal cortex (healthy volunteers 987 ± 102 ms; kidney transplantation 1299 ± 101 ms, p < 0.001; lung transplantation 1058 ± 96 ms, p < 0.05) and to a lesser extent in the renal medulla. Accordingly, the corticomedullary difference was diminished shortly after solid organ transplantation. T1 changes were more pronounced following kidney compared to lung transplantation, were associated with the stage of renal impairment and significantly correlated with renal function. CONCLUSIONS: T1 mapping may be helpful for early non-invasive assessment of acute kidney injury and renal pathology following major surgery such as solid organ transplantation. KEY POINTS: • Renal cortical T1 relaxation times are prolonged after solid organ transplantation. • Cortical T1 values increase with higher stages of renal function impairment. • Corticomedullary difference decreases with higher stages of renal function impairment. • Renal cortical T1 relaxation time and corticomedullary difference correlate with renal function. • T1 mapping may be helpful for non-invasive assessment of post-operative renal pathology.

Evaluation of MRI/Ultrasound Fusion-Guided Prostate Biopsy Using Transrectal and Transperineal Approaches.

PURPOSE: To evaluate transrectal (TR) and transperineal (TP) approaches for MRI/ultrasound (MRI/US) fusion-guided biopsy to detect prostate cancer (PCa). MATERIALS AND METHODS: 154 men underwent multiparametric MRI and MRI/US fusion-guided biopsy between July 2012 and October 2016. 79/154 patients were biopsied with a TR approach and 75/154 with a TP approach. MRI was retrospectively analyzed according to PI-RADS version 2. PI-RADS scores were compared with histopathological results. Descriptive statistics, accuracy, and negative and positive predictive values were calculated. Histopathological results of first, second, and third MRI targeted biopsy cores were compared to evaluate the impact of one verus multiple targeted cores. RESULTS: Detection rates of PCa were 39% for TR biopsy and 75% for TP biopsy. Sensitivity/specificity for tumor detection with PI-RADS ≥ 4 were 81/69% for TR biopsy and 86/84% for TP biopsy. In 31% for TR biopsy and 19% for TP biopsy, PCa was found in the second or third MRI targeted biopsy core only. CONCLUSION: MRI/US fusion-guided biopsy may be conducted with the TR as well as the TP approach with high accuracy, giving more flexibility for diagnosis and the option for focal treatment of PCa.

Functional MRI for characterization of renal perfusion impairment and edema formation due to acute kidney injury in different mouse strains.

PURPOSE: The purpose was to characterize acute kidney injury (AKI) in C57BL/6 (B6)- and 129/Sv (Sv)-mice by noninvasive measurement of renal perfusion and tissue edema using functional MRI. METHODS: Different severities of AKI were induced in B6- and Sv-mice by renal ischemia reperfusion injury (IRI). Unilateral clamping of the renal pedicle for 35 min (moderate AKI) or 45 min (severe AKI) was done. MRI (7-Tesla) was performed 1, 7 and 28 days after surgery using a flow alternating inversion recovery (FAIR) arterial spin labeling (ASL) sequence. Maps of perfusion and T1-relaxation time were calculated. Relative MRI-parameters of the IRI kidney compared to the contralateral not-clipped kidney were compared between AKI severities and between mouse strains using unpaired t-tests. In addition, fibrosis was assessed by Masson Trichrome and collagen IV staining. RESULTS: After moderate AKI relative perfusion impairment was significantly higher in B6- than in Sv-mice at d7 (55±7% vs. 82±8%, p<0.05) and d28 (76±7% vs. 102±3%, p<0.01). T1-values increased in the early phase after AKI in both mouse strains. T1-increase was more severe after prolonged ischemia times of 45 min compared to 35 min in both mouse strains, measured in the renal cortex and outer stripe of outer medulla. Kidney volume loss (compared to the contralateral kidney) occurred already after 7 days but proceeded markedly towards 4 weeks in severe AKI. Early renal perfusion impairment was predictive for later kidney volume loss. The progression to chronic kidney disease (CKD) in the severe AKI model was similar in both mouse strains as revealed by histology. CONCLUSION: Quantification of renal perfusion and tissue edema by functional MRI allows characterization of strain differences upon AKI. Renal perfusion impairment was stronger in B6- compared to Sv-animals following moderate AKI. Prolonged ischemia times were associated with more severe perfusion impairment and edema formation in the early phase and progression to CKD within 4 weeks of observation.

Standardized Reporting of Prostate MRI: Comparison of the Prostate Imaging Reporting and Data System (PI-RADS) Version 1 and Version 2.

INTRODUCTION: Objective of our study was to determine the agreement between version 1 (v1) and v2 of the Prostate Imaging Reporting and Data System (PI-RADS) for evaluation of multiparametric prostate MRI (mpMRI) and to compare their diagnostic accuracy, their inter-observer agreement and practicability. MATERIAL AND METHODS: mpMRI including T2-weighted imaging, diffusion-weighted imaging (DWI) and dynamic contrast-enhanced imaging (DCE) of 54 consecutive patients, who subsequently underwent MRI-guided in-bore biopsy were re-analyzed according to PI-RADS v1 and v2 by two independent readers. Diagnostic accuracy for detection of prostate cancer (PCa) was assessed using ROC-curve analysis. Agreement between PI-RADS versions and observers was calculated and the time needed for scoring was determined. RESULTS: MRI-guided biopsy revealed PCa in 31 patients. Diagnostic accuracy for detection of PCa was equivalent with both PI-RADS versions for reader 1 with sensitivities and specificities of 84%/91% (AUC = 0.91 95%CI[0.8-1]) for PI-RADS v1 and 100%/74% (AUC = 0.92 95% CI[0.8-1]) for PI-RADS v2. Reader 2 achieved similar diagnostic accuracy with sensitivity and specificity of 74%/91% (AUC = 0.88 95%CI[0.8-1]) for PI-RADS v1 and 81%/91% (AUC = 0.91 95%CI[0.8-1]) for PI-RADS v2. Agreement between scores determined with different PI-RADS versions was good (reader 1: κ = 0.62, reader 2: κ = 0.64). Inter-observer agreement was moderate with PI-RADS v2 (κ = 0.56) and fair with v1 (κ = 0.39). The time required for building the PI-RADS score was significantly lower with PI-RADS v2 compared to v1 (24.7±2.3 s vs. 41.9±2.6 s, p<0.001). CONCLUSION: Agreement between PI-RADS versions was high and both versions revealed high diagnostic accuracy for detection of PCa. Due to better inter-observer agreement for malignant lesions and less time demand, the new PI-RADS version could be more practicable for clinical routine.

Diffusion-Weighted imaging and diffusion tensor imaging detect delayed graft function and correlate with allograft fibrosis in patients early after kidney transplantation.

PURPOSE: To combine diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) for detection of allograft dysfunction in patients early after kidney transplantation and to correlate diffusion parameters with renal function and renal histology of allograft biopsies. MATERIALS AND METHODS: Between day 4 and 11 after kidney transplantation 33 patients with initial graft function and 31 patients with delayed graft function (DGF) were examined with a 1.5T magnetic resonance imaging (MRI) scanner. DTI and DWI sequences were acquired and fractional anisotropy (FA), apparent diffusion coefficient (ADCmono), pure diffusion (ADCdiff ), and the perfusion fraction (Fp) were calculated. Kidney biopsies in 26 patients were analyzed for allograft pathology, ie, acute tubular injury, inflammation, edema, renal fibrosis, and rejection. Histological results were correlated with MRI parameters. RESULTS: In the renal medulla FA (0.25 ± 0.06 vs. 0.29 ± 0.06, P < 0.01) and ADCmono (1.73 ± 0.13*10(-3) vs. 1.93 ± 0.16*10(-3) mm(2) /s, P < 0.001) were significantly reduced in DGF patients compared with patients with initial function. For ADCdiff and Fp similar reductions were observed. FA and ADCmono significantly correlated with renal function (r = 0.53 and r = 0.57, P < 0.001) and were inversely correlated with the amount of renal fibrosis (r = -0.63 and r = -0.65, P < 0.05). CONCLUSION: Combined DTI and DWI detected allograft dysfunction early after kidney transplantation and correlated with allograft fibrosis. J. Magn. Reson. Imaging 2016;44:112-121.

Functional MRI detects perfusion impairment in renal allografts with delayed graft function.

Delayed graft function (DGF) after kidney transplantation is not uncommon, and it is associated with long-term allograft impairment. Our aim was to compare renal perfusion changes measured with noninvasive functional MRI in patients early after kidney transplantation to renal function and allograft histology in biopsy samples. Forty-six patients underwent MRI 4-11 days after transplantation. Contrast-free MRI renal perfusion images were acquired using an arterial spin labeling technique. Renal function was assessed by estimated glomerular filtration rate (eGFR), and renal biopsies were performed when indicated within 5 days of MRI. Twenty-six of 46 patients had DGF. Of these, nine patients had acute rejection (including borderline), and eight had other changes (e.g., tubular injury or glomerulosclerosis). Renal perfusion was significantly lower in the DGF group compared with the group with good allograft function (231 ± 15 vs. 331 ± 15 ml·min(-1)·100 g(-1), P < 0.001). Living donor allografts exhibited significantly higher perfusion values compared with deceased donor allografts (P < 0.001). Renal perfusion significantly correlated with eGFR (r = 0.64, P < 0.001), resistance index (r = -0.57, P < 0.001), and cold ischemia time (r = -0.48, P < 0.01). Furthermore, renal perfusion impairment early after transplantation predicted inferior renal outcome and graft loss. In conclusion, noninvasive functional MRI detects renal perfusion impairment early after kidney transplantation in patients with DGF.

Targeted MRI/TRUS fusion-guided biopsy in men with previous prostate biopsies using a novel registration software and multiparametric MRI PI-RADS scores: first results.

PURPOSE: To evaluate a novel system for MRI/TRUS fusion-guided biopsy for detection of prostate cancer (PCa) in patients with previous negative prostate biopsy and determine diagnostic accuracy when using the Prostate Imaging Reporting and Data System (PI-RADS) for multiparametric magnetic resonance imaging (mpMRI) as proposed by the European Society of Urogenital Radiology. METHODS: Thirty-nine men with clinical suspicion of PCa and history of previous prostate biopsy underwent mpMRI on a 3-T MRI. In total, 72 lesions were evaluated by the consensus of two radiologists. PI-RADS scores for each MRI sequence, the sum of the PI-RADS scores and the global PI-RADS were determined. MRI/TRUS fusion-guided targeted biopsy was performed using the BioJet™ software combined with a transrectal ultrasound system. Image fusion was based on rigid registration. PI-RADS scores of the dominant lesion were compared with histopathological results. Diagnostic accuracy was determined using receiver operating characteristic curve analysis. RESULTS: MRI/TRUS fusion-guided biopsy was reliable and successful for 71 out of 72 lesions. The global PI-RADS score of the dominant lesion was significantly higher in patients with PCa (4.0 ± 1.3) compared to patients with negative histopathology (2.6 ± 0.8; p = 0.0006). Using a global PI-RADS score cut-off ≥4, a sensitivity of 85 %, a specificity of 82 % and a negative predictive value of 92 % were achieved. CONCLUSIONS: The described fusion system is dependable and efficient for targeted MRI/TRUS fusion-guided biopsy. mpMRI PI-RADS scores combined with a novel real-time MRI/TRUS fusion system facilitate sufficient diagnosis of PCa with high sensitivity and specificity.

T1-mapping for assessment of ischemia-induced acute kidney injury and prediction of chronic kidney disease in mice.

OBJECTIVES: To investigate whether T1-mapping allows assessment of acute kidney injury (AKI) and prediction of chronic kidney disease (CKD) in mice. METHODS: AKI was induced in C57Bl/6N mice by clamping of the right renal pedicle for 35 min (moderate AKI, n = 26) or 45 min (severe AKI, n = 23). Sham animals served as controls (n = 9). Renal histology was assessed in the acute (day 1 + day 7; d1 + d7) and chronic phase (d28) after AKI. Furthermore, longitudinal MRI-examinations (prior to until d28 after surgery) were performed using a 7-Tesla magnet. T1-maps were calculated from a fat-saturated echoplanar inversion recovery sequence, and mean and relative T1-relaxation times were determined. RESULTS: Renal histology showed severe tubular injury at d1 + d7 in both AKI groups, whereas, at d28, only animals with prolonged 45-min ischemia showed persistent signs of AKI. Following both AKI severities T1-values significantly increased and peaked at d7. T1-times in the contralateral kidney without AKI remained stable. At d7 relative T1-values in the outer stripe of the outer medulla were significantly higher after severe than after moderate AKI (138 ± 2% vs. 121 ± 3%, p = 0.001). T1-elevation persisted until d28 only after severe AKI. Already at d7 T1 in the outer stripe of the outer medulla correlated with kidney volume loss indicating CKD (r = 0.83). CONCLUSION: T1-mapping non-invasively detects AKI severity in mice and predicts further outcome. KEY POINTS: Renal T1-relaxation times are increased after ischemia-induced acute kidney injury. Renal T1-values correlate with subsequent kidney volume loss. T1-mapping detects the severity of acute kidney injury and predicts further outcome.