MO889: High Flux Dialyzer 2.6 M2 is Promising for Free Light Chains Removal in High Flux Hemodialysis and Hemodiafiltration

BACKGROUND AND AIMS

Immunoglobulin light chains are classified as middle molecule uremic toxins and its removal through effective dialyzer is needed with less albumin loss. This study assessed the free light chains removal using dialyzer surface area (SA) 2.6m2 in high flux dialysis (HD) versus hemodiafiltration (HDF) and its relation to cumulative albumin loss.

METHOD

A cross-over study included 25 patients who underwent hemodialysis using dialyzer surface area 2.6 m2 in high flux HD followed by online post-dilution hemodiafiltration with washout period 2 weeks using high flux dialyzers (max 2.0 m2 SA). All patients were subjected to single session measurement of dialysate albumin every hour and pre-post dialysis Free light chains (FLC) kappa and Lambda by ELISA.

RESULTS

Dialyzer (SA) 2.6m2 showed significant reduction in post-dialysis kappa and lambda in comparison to pre-dialysis level in high flux hemodialysis and hemodiafiltration (P < 0.001). HDF showed higher kappa and lambda FLC reduction ratio (45.16 ± 6.53 ng/mL), (28.68 ± 4.36 ng/mL), respectively compared with high flux HD (29.52 ± 6.38 ng/mL), (19.48 ± 1.96 ng/mL), respectively (P < 0.001). HDF/HD fold change of kappa and lamda were (1.56 ± 0.23) and (1.48 ± 0.26), respectively. Patients on HDF dialysis had significant total albumin loss in dialysate [median (IQR) 2.47 (1.16) gm/dL] compared with high flux dialysis [median (IQR) 0.65 (0.64) gm/dL] with (P < 0.001). Maximum albumin loss in patients on HDF was in the first hour [median (IQR) 1.22 (0.59)] gm/dL with lower albumin loss in the next hours reaching median {0.17 (0.15) gm/dL} in the fourth hour. Trans-membrane pressure was positively correlated with total albumin loss in high flux hemodialysis and hemodiafiltration (r 0.443, p 0.027, r 0.745, P = 0.001), respectively.

CONCLUSION

High flux dialyzer 2.6 m2 (SA) is effective for free light chains removal especially with online post-dilution hemodiafiltration with acceptable albumin loss.

Performance of intermittently scanned continuous glucose monitoring systems in people with type 1 diabetes: A pooled analysis

AIMS

To conduct a pooled analysis to assess the performance of intermittently scanned continuous glucose monitoring (isCGM) in association with the rate of change in sensor glucose in a cohort of children, adolescents, and adults with type 1 diabetes.

MATERIAL AND METHODS

In this pooled analysis, isCGM system accuracy was assessed depending on the rate of change in sensor glucose. Clinical studies that have been investigating isCGM accuracy against blood glucose, accompanied with collection time points were included in this analysis. isCGM performance was assessed by means of median absolute relative difference (MedARD), Parkes error grid (PEG) and Bland-Altman plot analyses.

RESULTS

Twelve studies comprising 311 participants were included, with a total of 15 837 paired measurements. The overall MedARD (interquartile range) was 12.7% (5.9-23.5) and MedARD differed significantly based on the rate of change in glucose (P < 0.001). An absolute difference of -22 mg/dL (-1.2 mmol/L) (95% limits of agreement [LoA] 60 mg/dL (3.3 mmol/L), -103 mg/dL (-5.7 mmol/L)) was found when glucose was rapidly increasing (isCGM glucose minus reference blood glucose), while a -32 mg/dL (1.8 mmol/L) (95% LoA 116 mg/dL (6.4 mmol/L), -51 mg/dL (-2.8 mmol/L)) absolute difference was observed in periods of rapidly decreasing glucose.

CONCLUSIONS

The performance of isCGM was good when compared to reference blood glucose measurements. The rate of change in glucose for both increasing and decreasing glucose levels diminished isCGM performance, showing lower accuracy during high rates of glucose change.

Impact of Weight Reduction on Thyroid Function and Nonalcoholic Fatty Liver among Egyptian Adolescents with Obesity

BACKGROUND

The prevalence of childhood obesity has been increasing worldwide. This may explain the emergence of nonalcoholic fatty liver as the leading cause of liver disease. Several previous studies have addressed the association between thyroid function and nonalcoholic fatty liver disease.

OBJECTIVES

To study the impact of weight reduction through lifestyle modifications in adolescents with obesity.

METHODS

A prospective cohort study was done on 61 adolescents with obesity. Patients were evaluated at the first visit by the full history, clinical examination, and investigations (thyroid profile, lipid profile, liver function tests, HbA1c, and liver ultrasonography) as basal information. The intervention program included a dietary program, increasing physical activity, and decreasing sedentary activity. A postintervention evaluation was done at the end of six months which included anthropometric measures, laboratory results, and ultrasonographic estimation.

RESULTS

It was shown that the mean BMI of the participants had significantly decreased after lifestyle modification from (32.05 ± 3.36 kg/m2) to (28.1 ± 2.77 kg/m2) (P < 0.001). It also showed that the percentage of studied adolescents with elevated TSH decreased from 47.5% to 19.7% after the weight reduction program. Improvement was also achieved in the lipid profile and liver functions. The percentage of studied adolescents with ultrasound appearance of NAFLD decreased from 31.1% to 26.2% after weight reduction.

CONCLUSIONS

Lifestyle modification positively influences the metabolic derangement in obesity without medical treatment. ΔTSH is a significant predictor of the change in BMI z-score. It is also possible that hepatic steatosis affects thyroid function rather than the other way around.

People with type 1 diabetes and impaired awareness of hypoglycaemia have a delayed reaction to performing a glucose scan during hypoglycaemia: a prospective observational study

AIMS

Considering that people with type 1 diabetes and impaired awareness of hypoglycaemia (IAH) have a delayed perception of hypoglycaemia, the question arises whether they perform scans later in case of hypoglycaemia than people without IAH. We assessed whether time to performing a scan after reaching hypoglycaemia while using a flash glucose monitoring (flash GM) system is different in people with IAH compared with people without IAH.

METHODS

Ninety-two people with type 1 diabetes [mean (± sd) age 42 ± 14 years, HbA1c 57 ± 9 mmol/mol] using a flash GM system for 3 months were included. Flash GM data were assessed for time until scan after reaching hypoglycaemia level 1 (< 3.9 mmol/l) and level 2 (< 3.0 mmol/l) and compared for type 1 diabetes with vs. without IAH via unpaired t-test/Mann-Whitney U test (P < 0.05).

RESULTS

Significant differences were found only for the delay between reaching hypoglycaemia and scan between people with and without IAH for Gold score [hypoglycaemia level 1: IAH 78 (51-105) min vs. without IAH 63 (42-89) min, P = 0.03; night-time hypoglycaemia level 2: IAH 140 (107-227) min vs. without IAH 96 (41-155) min, P = 0.004] and Pedersen-Bjergaard score [hypoglycaemia level 1: IAH 76 (52-97) min vs. without IAH 54 (38-71) min, P = 0.011; night-time hypoglycaemia level 1: IAH 132 (79-209) min vs. without IAH 89 (59-143) min, P = 0.011; night-time hypoglycaemia level 2: IAH 134 (66-212) min vs. without IAH 80 (37-131) min, P = 0.002). Data are shown as median (i.q.r.).

CONCLUSIONS

Time until scan after reaching hypoglycaemia might be an objective assessment tool for IAH, but needs to be investigated comprehensively in future studies.

A head-to-head comparison of personal and professional continuous glucose monitoring systems in people with type 1 diabetes: Hypoglycaemia remains the weak spot

To compare the performance of a professional continuous glucose monitoring (proCGM) and a personal continuous glucose monitoring (persCGM) system worn in parallel under standardized conditions in individuals with type 1 diabetes (T1D), two CGM systems (iPro2 - proCGM; Minimed 640G - persCGM) worn in parallel using the same sensor (Enlite 2) were compared. Ten people with T1D were included in this single-centre, open-label study in which CGM performance was evaluated. The study consisted of a 24-hours inpatient phase (meals, exercise, glycaemic challenges) and a 4-day home phase. Analyses included fulfilment of ISO 15197:2013 criteria, mean absolute relative difference (MARD), Parkes Error Grid and Bland-Altman plots. During the inpatient stay, ISO 15197:2013 criteria fulfilment was 58.4% (proCGM) and 57.8% (persCGM). At home, the systems met ISO 15197:2013 criteria by 66.5% (proCGM) and 65.3% (persCGM). No difference of MARD in inpatient phase (19.1 ± 16.7% vs. 19.0 ± 19.6; P = 0.83) and home phase (18.6 ± 26.8% vs. 17.4 ± 21.3%, P = 0.87) was observed. All sensors performed less accurately during hypoglycaemia. ProCGM and persCGM showed similar performance during daytime and night-time for the inpatient and the home phase. However, sensor performance was reduced during hypoglycaemia for both systems.

MicroRNA 499 gene expression in patients on hemodialysis with cardiovascular complications

BACKGROUND

MicroRNA (miRNA) 499 is an evolutionarily conserved muscle-specific miRNA that is encoded by an intron of the myh7 gene and is likely to play a role in myosin gene regulation. It has been shown to be involved in inhibiting apoptosis and myocardial infarction induced by ischemia and anoxia. It is unknown whether levels of miRNAs are affected in patients undergoing hemodialysis.

OBJECTIVE

The aim of this study was to assess circulating levels of miRNA 499 in hemodialysis patients and whether the levels are affected by dialyzer membranes (high flux vs. low flux).

METHODS

The studied population consisted of 32 end stage renal disease (ESRD) patients (22 males and 10 females) with age ranged from 38% to 75% years on regular hemodialysis (4 hours, 3 times weekly) for at least 1 year duration with cardiovascular events in the last 6 months and 32 healthy controls (20 males and 12 females) with an age range from 54 to 60 years. Patients were involved into a two-stage sequential study; high-flux hemodialysis stage (stage I), then low-flux hemodialysis stage (stage II). Expressed levels of plasma miRNA 499 have been measured by Real Time-PCR. Lipid profile, serum phosphorus, serum calcium, serum creatinine, and blood urea were measured in all patients.

RESULTS

In this study, 2 patients with an open-heart surgery showed highly elevation in the miRNA 499, while the other patients, showing different degrees of ischemia, had different levels of elevated miRNA 499. Statistically significant higher levels of miRNA 499 in plasma were observed in all the studied patients with cardiovascular diseases compared to the levels of miRNA 499 found in healthy controls (P < 0.0001). MicroRNA 499 was found to be a dialyzable marker. A significant decrease in plasma levels of miRNA 499 was obtained after either high-flux or low-flux dialysis compared to plasma levels of miRNA 499 found before dialysis (P < 0.0001). On comparing both types of hemodialysis membranes with respect to miRNA 499 clearance, we found that low-flux membrane showed better clearance for miRNA 499 than high-flux membrane with a statistically significant difference between them (P < 0.001).

CONCLUSION

In conclusion, miRNA 499 levels are elevated in patients with ESRD with cardiovascular complications. High-flux membrane seems to be less efficient in miRNA 499 clearance in cardiac patients on hemodialysis.

Evaluation of subcutaneous glucose monitoring systems under routine environmental conditions in patients with type 1 diabetes

Continuous and flash glucose monitoring (GM) systems have been established in diabetes care. We compared the sensor performance of 3 commercially available GM systems. A total of 12 patients with type 1 diabetes were included in a single-centre, open-label study in which the sensor performance of the Abbott FreeStyle libre (Abbott), Dexcom G4 Platinum (Dexcom) and Medtronic MiniMed 640G (Medtronic) systems over 12 hours was compared during mimicked real-life conditions (meals, exercise, hypo- and hyperglycaemia). Sensor performance was determined by fulfilment of ISO 15197:2013 criteria, calculating mean absolute relative difference (MARD), and was also illustrated using Parkes error grid and Bland-Altman plots. Sensor performance during changes in metabolic variables (lactate, betahydroxybutyrate, glucagon, non-esterified-fatty-acids) was determined by Spearman's rank correlation coefficient testing. The systems fulfilled ISO 15197:2013 criteria by 73.2% (Abbott), 56.1% (Dexcom) and 52.0% (Medtronic). The MARDs ± standard deviation in the entire glycaemic range were 13.2% ± 10.9% (Abbott), 16.8% ± 12.3% (Dexcom) and 21.4% ± 17.6% (Medtronic), respectively. All sensors performed less accurately during hypoglycaemia and best during hyperglycaemia. We did not observe an influence of metabolic variables on sensor performance.

Direct ink writing of silica-bonded calcite scaffolds from preceramic polymers and fillers

Silica-bonded calcite scaffolds have been successfully 3D-printed by direct ink writing, starting from a paste comprising a silicone polymer and calcite powders, calibrated in order to match a SiO₂/CaCO₃ weight balance of 35/65. The scaffolds, fabricated with two slightly different geometries, were first cross-linked at 350 °C, then fired at 600 °C, in air. The low temperature adopted for the conversion of the polymer into amorphous silica, by thermo-oxidative decomposition, prevented the decomposition of calcite. The obtained silica-bonded calcite scaffolds featured open porosity of about 56%-64% and compressive strength of about 2.9-5.5 MPa, depending on the geometry. Dissolution studies in SBF and preliminary cell culture tests, with bone marrow stromal cells, confirmed the in vitro bioactivity of the scaffolds and their biocompatibility. The seeded cells were found to be alive, well anchored and spread on the samples surface. The new silica-calcite composites are expected to be suitable candidates as tissue-engineering 3D scaffolds for regeneration of cancellous bone defects.

First-line tracheal resection and primary anastomosis for postintubation tracheal stenosis

Introduction Tracheal stenosis following intubation is the most common indication for tracheal resection and reconstruction. Endoscopic dilation is almost always associated with recurrence. This study investigated first-line surgical resection and anastomosis performed in fit patients presenting with postintubation tracheal stenosis. Methods Between February 2011 and November 2014, a prospective study was performed involving patients who underwent first-line tracheal resection and primary anastomosis after presenting with postintubation tracheal stenosis. Results A total of 30 patients (20 male) were operated on. The median age was 23.5 years (range: 13-77 years). Seventeen patients (56.7%) had had previous endoscopic tracheal dilation, four (13.3%) had had tracheal stents inserted prior to surgery and one (3.3%) had undergone previous tracheal resection. Nineteen patients (63.3%) had had a tracheostomy. Eight patients (26.7%) had had no previous tracheal interventions. The median time of intubation in those developing tracheal stenosis was 20.5 days (range: 0-45 days). The median length of hospital stay was 10.5 days (range: 7-21 days). The success rate for anastomoses was 96.7% (29/30). One patient needed a permanent tracheostomy. The in-hospital mortality rate was 3.3%: 1 patient died from a chest infection 21 days after surgery. There was no mortality or morbidity in the group undergoing first-line surgery for de novo tracheal lesions. Conclusions First-line tracheal resection with primary anastomosis is a safe option for the treatment of tracheal stenosis following intubation and obviates the need for repeated dilations. Endoscopic dilation should be reserved for those patients with significant co-morbidities or as a temporary measure in non-equipped centres.

Bilateral cystic encephalomalacia following multiple intrauterine transfusions for anti-Kell isoimmunisation

Fetal and neonatal haemolytic diseases result from maternal allo-immunisation to fetal antigens. Maternal antibodies cross the placenta causing red cell haemolysis, resulting in fetal anaemia and, in severe cases, hydrops and perinatal death. Intravascular intrauterine blood transfusion (IUT) has markedly reduced perinatal mortality and is now a standard procedure. IUT is considered to be a safe procedure with fetal loss rate reported to be less than 5% and no reported increase in the rate of neurodevelopment impairment. In this report, we are presenting a case of bilateral cystic encephalomalacia following fetal anaemia secondary to anti-Kell iso-immunisation treated with multiple IUTs. Such a significant adverse outcome following IUT for anti-Kell iso-immunisation has not been reported in the literature. This case highlights the need for appropriate parental counselling and routine postnatal head ultrasound in all babies delivered following multiple IUTs.

The impact of systemic fungal infection in patients with perforated oesophagus

INTRODUCTION

Perforated oesophagus is a surgical emergency with significant morbidity and mortality. Systemic fungal infection represents a poor response to the magnitude of the insult, which adds significantly to the risk of morbidity and mortality in these patients. We reviewed our experience with this group of patients over a six-year period in a tertiary referral centre.

METHODS

A retrospective clinical review was conducted of patients who were admitted following a ruptured oesophagus over a period of six years (January 2002 - January 2008).

RESULTS

We had 27 admissions (18 men and 9 women) following an isolated perforated oesophagus to our unit. The median patient age was 65 years (range: 22-87 years). The majority (n=24, 89%) presented with spontaneous perforations (Boerhaave's syndrome) and three (11%) were iatrogenic. Fungal organisms, predominantly Candida albicans, were positively cultured in pleural or blood samples in 16 (59%) of the 27 patients. Fourteen patients grew yeasts within the first seven days while two showed a delayed growth after ten days. Overall mortality was 5 out of 27 patients (19%). There was no mortality among the group that did not grow yeasts in their blood/pleural fluid while mortality was 31% (5/16) in the group with systemic fungal infection (p<0.001). A positive fungal culture was also associated with increase ventilation time, intensive care unit stay and inpatient hospital stay but not an increased rate of complications.

CONCLUSIONS

Systemic fungal infection in patients with a ruptured oesophagus affects a significant proportion of these patients and carries a poor prognosis despite advanced critical care interventions. It may represent a general marker of poor host response to a major insult but can add to mortality and morbidity. It is worth considering adding antifungal therapy empirically at an early stage to antimicrobials in patients with an established diagnosis of a perforated oesophagus.

Air leaks following pulmonary resection for lung cancer: is it a patient or surgeon related problem?

INTRODUCTION

Prolonged air leak (PAL) is the most common complication after partial lung resection and the most important determinant of length of hospital stay for patients post-operatively. The aim of this study was to determine the risk factors involved in developing air leaks and the consequences of PAL.

METHODS

All patients undergoing lung resection between January 2002 and December 2007 in our hospital were studied retrospectively. Univariate analysis to predict risk factors for developing post-operative air leaks included patient demographics, smoking status, pulmonary function tests, disease aetiology (benign, malignant), neoadjuvant therapy (pre-operative radiotherapy/chemotherapy), extent and type of resection, and different consultant surgeons' practice. A logistic regression model was used for multivariate analysis.

RESULTS

A total of 1,911 lung resections were performed over the 6-year study period. An air leak lasting more than 6 days post-operatively was present in 129 patients (6.7%). This included 100 out of the 1,250 patients (8%) from the lobectomy group and 29 out of the 661 patients (4.4%) from the wedge/segmentectomy group. Using the multivariate analysis, the risk factors for developing an air leak included a low predicted forced expiratory volume in 1 second (pFEV(1)) (p<0.001), performing an upper lobectomy (p=0.002) and different consultant practice (p=0.02). PAL was associated with increased length of stay (p<0.0001), in-hospital mortality (p=0.003) and intensive care unit readmission (p=0.05).

CONCLUSIONS

Air leaks after pulmonary resections were at an acceptable rate in our series. Particular patients are at a higher risk but meticulous surgical technique is vital in reducing their incidence. Our study shows that pFEV1 is the strongest predictor of post-operative air leaks.

Prevalence and association of post-renal transplant anemia

In some renal allograft recipients, anemia persists or develops following transplantation. Anemia is associated with pre-operative blood loss and allograft dysfunction, including delayed graft function, acute rejection and chronic allograft dysfunction. To study the prevalence and association of post-renal transplant anemia, we studied 200 renal transplant recipients; 131 (65.5%) patients were males and 69 (34.5%) patients were females, and age ranged from 17 to 67 years, with a mean of 37.7 ± 10.8 years. All patients were receiving cyclosporine, prednisolone and mycophenolate mofetil (MMF). Complete blood count was done at two times: three and six months post-renal transplant. There were 74% anemic patients three months after renal transplantation and 45% anemic patients six months after renal transplantation. High creatinine value, female gender, delayed graft function, episodes of acute rejection, perioperative blood loss and infections were the only significant independent risk factors for prevalence of anemia post-renal transplant. In our study, we did not find an association between MMF and cyclosporine nor angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptors blocker (ARBs) with anemia. This study demonstrates that anemia is a common complication during the first six months after kidney transplantation, with several risk factors precipitating this complication.

Malignant pleural mesothelioma presenting with a spontaneous hydropneumothorax: a report of 2 cases

Malignant pleural mesothelioma (MPM) originates in the mesothelial cells that line the pleural cavities. Most patients initially experience the insidious onset of chest pain or shortness of breath and have a history of asbestos exposure. It rarely presents as spontaneous pneumothorax. We report here two cases where malignant pleural mesothelioma presented with a spontaneous hydropneumothorax and was only discovered following surgery. We emphasise the need for a chest CT-scan preoperatively in older patients presenting with a secondary pneumo/hydropneumothorax.

Large pulmonary masses containing varicose veins: a rare presentation of benign metastasising leiomyomas

A 48-year-old woman presented with cough and chest pain. A chest radiograph and CT scans showed bilateral lung masses containing massive venous varices. A core biopsy specimen revealed benign metastasising leiomyoma with strong expression of progesterone receptors. A review of her medical history revealed a hysterectomy 11 years earlier. The lung masses showed significant reduction in size after induction of artificial menopause, although the pulmonary varices persisted.

Effects of a 2- to 4-week course of repetitive transcranial magnetic stimulation (rTMS) on neuropsychologic functioning, electroencephalogram, and auditory threshold in depressed patients

BACKGROUND

The safety of repetitive transcranial magnetic stimulation (rTMS) has only previously been formally studied in volunteers receiving a single session of stimulation or in a small number of depressed subjects receiving a 2-week treatment course. This study examined safety issues in depressed subjects receiving up to 4 weeks of rTMS. Efficacy results from this study have been previously reported.

METHODS

Eighteen subjects with DSM-IV major depression participated in a 2-week, parallel, double-blind, sham-controlled study of rTMS treatment. Twelve subjects then went on to receive 4 weeks active rTMS in an open follow-up. We examined the effects of rTMS on neuropsychologic function (up to 4 weeks), auditory threshold (up to 6 weeks exposure to rTMS noise), and an electroencephalogram (after 2 weeks). Data were analyzed by repeated measures analysis.

RESULTS

There were trends for improvement in neuropsychologic performance, probably due to practice effects. No mean changes in auditory threshold occurred, but two patients showed mild high-frequency hearing loss after several weeks of rTMS. Electroencephalograms in two patients, one of whom had sham stimulation, showed minor abnormality.

CONCLUSIONS

No significant mean deficits were demonstrated in this cohort. Overall, rTMS for up to 4 weeks is safe, but individual results suggest caution and the need for further investigation of the safety of several weeks of rTMS.

Imaging of an unusual case of parasitic twinning

Conjoined twins are rare in the literature and parasitic conjoined twins are rarer still. To our knowledge no cases of parasitic conjoined twins have previously been reported in the radiology literature. We present a case of parasitic conjoined twins in which radiographic findings played an important role in management.

Shock sensitization of startle in rats: the role of contextual conditioning

The role of contextual conditioning in the shock sensitization of startle effect was examined in 2 experiments with rats. Experiment 1 showed that shock sensitized the startle response only if it was given in the test context, and Experiment 2 showed that the sensitization effect was abolished in subjects preexposed to the test context. Taken together, these results show that shock sensitization of startle is mediated by contextual conditioning. The implications of this finding for using the shock sensitization of startle procedure as a model preparation for examining the neural and pharmacological bases of unconditioned fear are discussed.

Shock sensitization of startle in rats: the role of contextual conditioning

The role of contextual conditioning in the shock sensitization of startle effect was examined in 2 experiments with rats. Experiment 1 showed that shock sensitized the startle response only if it was given in the test context, and Experiment 2 showed that the sensitization effect was abolished in subjects preexposed to the test context. Taken together, these results show that shock sensitization of startle is mediated by contextual conditioning. The implications of this finding for using the shock sensitization of startle procedure as a model preparation for examining the neural and pharmacological bases of unconditioned fear are discussed.