Implementation of a new surveillance system for dialysis-associated infection events in outpatient dialysis facilities in Germany.

INTRODUCTION: Patients receiving maintenance haemodialysis are at risk of catheter-related infections. Up to now, there has been no standardized surveillance tool in Germany to evaluate infection events in haemodialysis outpatients. As such, this study aimed to implement an online-based surveillance tool in outpatient dialysis facilities, and to report the first national surveillance data for haemodialysis patients in Germany from October 2019 until September 2021. METHODS: Outpatient dialysis facilities reported three types of dialysis-associated infection event (DAIE): bloodstream infections, intravenous antimicrobial starts, and local access site infections. Denominator data were provided by the number of haemodialysis treatments at each facility per month. DAIE rates stratified by vascular access type were calculated. RESULTS: In total, 43 outpatient dialysis facilities reported 723 DAIEs, including 63 bloodstream infections, 439 intravenous antimicrobial starts, and 221 local access site infections. The overall incidence of DAIEs was 0.51 per 1000 dialysis treatments (723/1,413,457) during the surveillance period. The overall incidence of DAIEs was 0.13 per 1000 dialysis treatments among patients with arteriovenous fistulas (AVFs; 126/990,392), 0.41 per 1000 dialysis treatments among patients with arteriovenous grafts (41/99,499), and 1.68 per 1000 dialysis treatments among patients with central venous catheters (CVCs; 535/318,757). The rate ratio of DAIEs between CVC and AVF rates was 13.2 (95% confidence interval 10.9-16.0; P<0.001). DISCUSSION: These 2-year infection data represent the first standardized data of outpatient dialysis facilities in Germany. Rates of infection were highest among patients with CVCs compared with other vascular access types. This online-based surveillance tool may be helpful to identify effective targets for infection prevention measures in haemodialysis patients.

Liver Assessment in Patients with Ataxia-Telangiectasia: Transient Elastography Detects Early Stages of Steatosis and Fibrosis.

Background: Ataxia-telangiectasia (A-T) is a rare autosomal-recessive multisystem disorder characterized by pronounced cerebellar ataxia, telangiectasia, cancer predisposition, and altered body composition. Liver diseases with steatosis, fibrosis, and hepatocellular carcinoma are frequent findings in older patients but sensitive noninvasive diagnostic tools are lacking. Objectives: To determine the sensitivity of transient elastography (TE) as a screening tool for early hepatic tissue changes and serum biomarkers for liver disease. Methods: Thirty-one A-T patients aged 2 to 25 years were examined prospectively from 2016-2018 by TE. In addition, we evaluated the diagnostic performance of liver biomarkers for steatosis and necroinflammatory activity (SteatoTest and ActiTest, Biopredictive, Paris) compared to TE. For calculation and comparison, patients were divided into two groups (<12, >12 years of age). Results: TE revealed steatosis in 2/21 (10%) younger patients compared to 9/10 (90%) older patients. Fibrosis was present in 3/10 (30%) older patients as assessed by TE. We found a significant correlation of steatosis with SteatoTest, alpha-fetoprotein (AFP), HbA1c, and triglycerides. Liver stiffness correlated significantly with SteatoTest, ActiTest, HbA1c, and triglycerides. Conclusion: Liver disease is a common finding in older A-T patients. TE is an objective measure to detect early stages of steatosis and fibrosis. SteatoTest and ActiTest are a good diagnostic assessment for steatosis and necroinflammatory activity in patients with A-T and confirmed the TE results.

Posterior urethral valves: prenatal diagnostic signs and outcome.

INTRODUCTION: Urethral valves can be of enormous clinical importance. Both the prognosis for an affected fetus and the indication for a prenatal therapeutic intervention depend to a high degree on the accuracy of the prenatal diagnosis. PATIENTS AND METHODS: The sonographic findings and the results of the postnatal diagnostic workup of 24 boys treated for urethral valves in our institute are analyzed in the present paper. RESULTS: Out of a group of 900 children, diagnosed prenatally as having urinary tract anomalies, the postnatal diagnostic workup revealed 24 boys suffering from posterior urethral valves. The combination of megacystis, oligohydramnios, and bilateral renal abnormalities was present in 3 boys, and it was only in these cases that urethral valves were correctly identified as the underlying pathology. The largest group (n = 16) of these fetuses presented with bilateral hydronephrosis with and without megaureter. Megacystis in any combination with other findings was detected only in 4 patients. Oligohydramnios as a sign of impaired renal function was observed in four pregnancies. Four children suffered postnatally from beginning renal insufficiency. Eight infants (33%) required some form of respiratory support. This group included the 4 newborns with oligohydramnios during the pregnancy. CONCLUSIONS: Posterior urethral valves represent a rare but severe congenital malformation. They can disrupt the development of the entire urinary tract and may be life-limiting to the affected boy. Only rarely, however, are they manifested as the complete pathological picture on prenatal ultrasound. In most cases, bilateral impairment of the fetal renal development suggests severe subvesical obstruction. Thus in cases with bilateral renal impairment on prenatal ultrasonography, posterior urethral valves are to be excluded postnatally. Oligohydramnios is a predictor of a poor outcome of the renal function.

[Prenatal diagnosis of obstructive uropathies - positive predictive value and effect on postnatal therapy]. / Pränatalsonographische Befunde bei obstruktiven Uropathien - positive Vorhersagefähigkeit und Bedeutung für die postnatale Therapie.

INTRODUCTION: Prenatal diagnosis of urological anomalies is a standard procedure nowadays. The aim of this study was first to define the frequency of urinary tract anomalies in the selected patients in a level III center for prenatal diagnostics and therapy. The second aim was to show the accuracy of prenatal diagnosis in the special groups of obstructive uropathies. PATIENTS AND METHODS: Postnatal diagnoses were used for control of the prenatal findings. In the 12-year retrospective study, we analyzed 21 616 pregnancies scanned for fetal anomalies. In 1 574 fetuses pediatric surgical anomalies were diagnosed. Out of 1 077 follow-ups 618 patients with urinary tract anomalies were found. RESULTS: It could be shown that prenatal ultrasound has a high sensitivity for the diagnosis of obstructive renal tract anomalies. The diagnosis of subpelvine obstruction and muticystic kidney dysplasia can be made with an accuracy of 97 and 98 %. The therapeutic relevance of the diagnosis "isolated hydronephrosis" increases up to 60 % when mild dilatation is neglected. False negative scans for urinary tract anomalies are low at 10 %. CONCLUSION: Hence, prenatal ultrasound for urinary tract anomalies is a method of high sensitivity. The therapeutic relevance is rather high. The most important question is to find all those patients who need a postnatal therapeutic approach immediately.

Follow-up of unilateral multicystic kidney dysplasia after prenatal diagnosis.

OBJECTIVES: Since the introduction of antenatal diagnostic screening, multicystic kidney dysplasia (MCKD) has been diagnosed in 1 of 4300 live births. We analyze our own experience and demonstrate a management regime based on these results and existing studies. METHODS: Retrospective data analysis was carried out in 110 patients, prenatally diagnosed with MCDK. A total of 93 patients with confirmed diagnosis of unilateral MCDK were born alive and followed up in our institutions. RESULTS: A total of 110 unilateral cystic kidneys were prenatally diagnosed; 93 were confirmed postnatally. These children were retrospectively allocated to two treatment groups: 51 were operated upon; 42 were treated conservatively. A micturition cystourethrogram was performed 88 times, yielding 20 pathological findings. Vesicoureteral reflux was identified 11 times (12.5%). Eleven children (12%) had associated non-urological abnormalities. Cardiac and musculoskeletal malformations predominated. After 1995, nephrectomy was performed only when clinically indicated. Thirty-seven children were treated conservatively for between 4 months and 6 years (mean 33 months); 28 dysplastic kidneys exhibited size reduction. Complete involution was noted in 16 of 28 children between 7 and 29 months (mean 16.2 months). CONCLUSION: This study provides evidence that neonatal nephrectomy of unilateral MCDK is rarely required. It also shows that the discussed malformation is not an isolated developmental abnormality. In a high proportion, associated urogenital abnormalities were present and therapeutically relevant, and determined the overall prognosis.

[Retrospective analysis of differential therapeutic measures in children with double kidney and ureter and hydronephrosis]. / Retrospektive Analyse des differentialtherapeutischen Vorgehens bei Kindern mit Doppelnieren mit Ureter duplex und Harntransportstörung.

In this study, we analyzed the findings of 79 duplex kidneys in 64 children treated at our institution between 1987 and 1999. Several reasons for impaired urine transport in a duplex kidney were clarified. A total of 55% of all patients manifested a variety of abnormal findings during prenatal screening. In the course of postnatal diagnostic work-up, renal units were classified according to their leading pathomorphological features: 44% showed a ureterocele, 29% nonfunctioning units at first diagnosis, and 27% vesicoureteric reflux. Nonfunctioning moieties had been heminephrectomized in most cases. In such nonfunctioning cases in the presence of associated ureteroceles, relief drainage was unsuccessful in our study. Reflux rarely matures. Ureterocystoneostomy is successful in 80% of our cases. In functioning units with a ureterocele, endoscopic therapy may be the one and only intervention needed. However, they commonly require secondary reconstructive measures.

[MRI in patients with cardiac pacemakers: in vitro and in vivo evaluation at 0.5 tesla]. / MRT bei Patienten mit Herzschrittmachern: In-vitro- und In-vivo-Evaluierung bei 0,5 Tesla.

PURPOSE: MRI is currently regarded as absolutely contraindicated in patients with implanted cardiac pacemakers. In this prospective study safety and feasibility of MRI in patients with new generation pacemakers (PM) was evaluated in vitro and in vivo. METHODS: 14 PM models in vitro and 18 patients with implanted new generation PM underwent a MRI exam at 0.5 Tesla with standard spin, turbo spin, and gradient echo (FFE) sequences under continuous ECG-monitoring. PM inquiry was performed before and after the MRI exam, including assessment of stimulation thresholds. RESULTS: In the static magnetic field all PM switched to the asynchronous mode due to activation of the Reed switch, resulting in continuous pacing at a fixed rate. In three PM models in vitro, however, after activation of the Reed switch, there was a software-induced switch back to the demand mode. In these PM inhibition and triggering were observed after starting the MRI scan due to influence of the pulsed magnetic fields. PM program changes, damage of PM components, dislocation/torque of the PM and rapid pacing of the PM were observed neither in vitro nor in vivo. Atrial and ventricular stimulation thresholds remained unchanged. CONCLUSION: MRI at 0.5 Tesla should not be regarded as absolutely contraindicated in patients with implanted new generation PM. However, knowledge of the behaviour of the specific PM model in static and pulsed magnetic fields is required, if necessary also changes of the PM program prior to the MRI exam, continuous ECG monitoring and cardiological stand-by.

Calcium homeostasis of isolated heart muscle cells exposed to pulsed high-frequency electromagnetic fields.

The intracellular calcium concentration ([Ca(2+)]i) of isolated ventricular cardiac myocytes of the guinea pig was measured during the application of pulsed high-frequency electromagnetic fields. The high-frequency fields were applied in a transverse electromagnetic cell designed to allow microscopic observation of the myocytes during the presence of the high-frequency fields. The [Ca(2+)]i was measured as fura-2 fluorescence by means of digital image analysis. Both the carrier frequency and the square-wave pulse-modulation pattern were varied during the experiments (carrier frequencies: 900, 1,300, and 1,800 MHz pulse modulated at 217Hz with 14 percent duty cycle; pulsation pattern at 900 MHz: continuous wave, 16 Hz, and 50 Hz modulation with 50 percent duty cycle and 30 kHz modulation with 80 percent duty cycle). The mean specific absorption rate (SAR) values in the solution were within one order of magnitude of 1 mW/kg. They varied depending on the applied carrier frequency and pulse pattern. The experiments were designed in three phases: 500 s of sham exposure, followed by 500 s of field exposure, then chemical stimulation without field. The chemical stimulation (K+ -depolarization) indicated the viability of the cells. The K+ depolarization yielded a significant increase in [Ca(2+)]i. Significant differences between sham exposure and high-frequency field exposure were not found except when a very small but statistically significant difference was detected in the case of 900 MHz/50 Hz. However, this small difference was not regarded as a relevant effect of the exposure.

Effects of nuclear magnetic resonance imaging on cardiac pacemakers.

Patients with cardiac pacemakers are currently restricted from nuclear magnetic resonance imaging (MRI). The aim of the study was to analyze the influence of MRI on new generation pacemakers. Tests were performed using a phantom model with seven dual chamber and two single chamber systems in a 0.5 Tesla MRI scanner. Monitoring by telemetry and oscillography were used during the standard clinical scan sequences as well as a pacemaker inquiry after each sequence. Spin echo, gradient echo, and fast field echo sequences were performed with the following stimulation modes: VVI, VVIR, VOO, DDD, DDDR, and DOO. On entering the static magnetic field, the reed switch was activated followed by asynchronous stimulation. The subsequent scan showed no influence on the stimulation function nor on the pacemaker program. Event counter function remained intact. Pacemakers with automatic mode switching to demand pacing or programmed inactivation of the reed switch were triggered in the dual chamber mode and were inhibited in the one chamber mode during the scan. Alterations of pacemaker program or rapid pacing were not observed. MRI scan could induce voltage as high as intracardiac signals, but the stimulation threshold of the heart was not reached. Thus, pacemakers should be programmed in the asynchronous mode during scan to avoid inhibition and trigger mechanism.