Determinants of Parathyroid Hormone Levels During the First Year After Kidney Transplantation

BackgroundSpontaneous remission of secondary hyperparathyroidism after kidney transplantation requires time to occur. The aim of the present study was to investigate factors that may be related to the reduction of parathyroid hormone (PTH) after transplantation as well as the rate of its reduction.MethodsWe studied 81 kidney transplant recipients at our transplantation center between January 2014 and September 2017. The relationship of PTH values during the first year after transplant with renal function, type of kidney graft origin (deceased or living), and delayed renal graft function was examined. Moreover, we determined the correlation of the rate of PTH reduction within the first year with the value of PTH before transplant.ResultsOf the total of 81 recipients, 28 (35.1%) were women and 53 (64.8%) were men, with a mean age of 47 ± 11.87 years. At the same time, there was a decrease of PTH by 33% in the first half of the first year after transplantation and by 57% in the second. In addition, a statistically significant correlation of PTH with renal function was found (P = .001), with PTH values decreasing as the glomerular filtration rate increased. Finally, transplants from deceased donors were associated with higher values of PTH, whereas the value of PTH before transplant was positively correlated with the value after it (P = .001).ConclusionsSecondary hyperparathyroidism, which accompanies end-stage chronic renal failure, usually resolves adequately after transplantation. The determinants of this resolution are the recipient's renal function, the kidney graft origin (deceased), and the pretransplant PTH values.     

Serum Leptin Levels After Bariatric Surgery Across a Range of Glucose Tolerance from Normal to Diabetes

Background: A longitudinal, clinical intervention study with bariatric surgery was done to investigate the relationship between leptin levels, BMI, and insulin during weight loss across a range of glucose tolerance from normal to diabetes. Methods: 43 morbidly obese patients (BMI: 42-75 kg/m²) undergoing vertical banded gastroplasty Roux-en-Y gastric bypass (VBG-RGB), were divided into 3 groups: 21 normal (NGT), 12 impaired glucose tolerance (IGT) and 10 type 2 diabetes (DM). Leptin, insulin, glucose, lipids and uric acid were measured at baseline and 2, 4, 6, and 12 months following surgery. Results: BMI fell from 54.1 ± 9.1 to 34.6 ± 6.3 kg/m², similarly in all groups. Leptin decreased from 73.9 ± 8.7 to 16.9 ± 10.2 ng/ml and was strongly correlated with BMI during 1-year follow-up (r=0.78; p<0.001). Linear univariate analysis for repeated evaluation showed a positive correlation between leptin and glucose, triglycerides, uric acid, and insulin. Multivariate regression analysis indicated that BMI was independently correlated with the decrease in leptin (p<0.001), accounting for 66% of the variance in leptin levels during weight loss. These results were found in the NGT and IGT groups. In the DM group, a small additional influence in leptin levels was attributed to glucose decrease. Conclusions: A strong link between leptin and BMI was found after surgery. BMI was the main determinant of the decrease of leptin. In these patients submitted to bariatric surgery, ranging from normal glucose tolerance to diabetes, changes in insulin levels and metabolic parameters, except for glucose in the DM group, did not appear to be correlated with changes in leptin levels.     

Changes in Ghrelin Levels Following Bariatric Surgery: Review of the Literature

Obesity is a severe health issue that is a global epidemic. Bariatric surgery is an accepted, popular, and effective therapy for weight loss. Ghrelin, a peptide secreted primarily by the fundus cells of the stomach, has been found to impact body weight by its influence on appetite. Although numerous studies have investigated serum ghrelin levels following bariatric surgery, there is no solid agreement yet as to the direction or magnitude of its change, or even its impact on weight loss. Some studies have found an increase in ghrelin, some have found a decrease, and others have found no change in ghrelin following bariatric surgery. The purpose of this review was to establish the impact of ghrelin changes following bariatric surgery.     

Serum Levels of Interleukin-12 in Graves' Disease and Their Dynamic Changes After Surgery

Purpose To investigate the role of interleukin-12 (IL-12) in Graves' disease, we measured the pre- and postoperative levels of serum IL-12 in patients undergoing surgery for Graves' disease. Methods The subjects of this study were 73 patients with Graves' disease, admitted for surgical treatment after taking antithyroid drugs for various durations. We collected blood from 11 of these patients, 1, 3, and 6 months postoperatively, to measure the serum IL-12 levels using a Human IL-12 +p40 Immunoassay Kit. Results The preoperative levels of serum IL-12 were higher in patients with Graves' disease than in healthy controls. Based on the preoperative data, there was a significant relationship between the levels of serum IL-12 and free T3. An analysis of the postoperative time course of these 11 patients showed that the levels of serum IL-12 decreased gradually from 1 month to 6 months, postoperatively. There was also a significant correlation between the levels of serum IL-12 and soluble IL-2R, and a significant negative correlation between the levels of serum IL-12 and thyroid-stimulating hormone receptor antibody. Conclusion Measurement of the levels of serum IL-12 may be a valuable immunological marker in the time course of treatment for Graves' disease.     

Acute Graft Pyelonephritis During the First Year After Renal Transplantation

Introduction

Urinary tract infections are the most common infections in renal transplant recipients. Acute graft pyelonephritis (AGPN) is considered a potential risk factor for poorer graft outcomes; however, its clinical impact still remains controversial.

Methods

This study analyzed urine cultures performed within the first 12 months after renal transplantation with reference to clinical data of patients who received a renal transplant at Gdańsk Transplantation Centre between January 2007 and December 2009. Renal function assessed by creatinine concentration and estimated glomerular filtration rate was recorded 24 months after renal transplantation.

Results

This study examined urine cultures and clinical data from 209 renal transplant recipients, including 59.3% men, with a mean age of 46 ± 14 years. We observed 70 AGPN episodes defined as the presence of significant bacteriuria, fever >38°, and/or graft pain and/or acute graft function impairment, including 13 cases of bacteremia, in 46 patients. This accounted for 22% of all diagnosed urinary tract infections. Over 80% of all AGPN episodes were diagnosed beginning from the second month posttransplantation, and the most frequently isolated uropathogen was Escherichia coli (65.7%, n = 46). Female sex, vesicoureteral reflux, or strictures at the ureterovesical junction and a history of cytomegalovirus infection emerged as independent predictors of AGPN. The evolution of renal graft function measured by serum creatinine concentration and MDRG eGFR rate did not differ significantly between patients with and without AGPN.

Conclusions

AGPN may be a marker of an underlying impairment of urine flow, eg, due to vesicoureteral reflux or strictures at the ureterovesical junction, whereas it does not affect graft function in renal transplant recipients.     

Evidence That the Length of Bile Loop Determines Serum Bile Acid Concentration and Glycemic Control After Bariatric Surgery

Background

Bariatric surgery contributes to the improvement in glucose metabolism that may be related to a postoperative increase in serum bile acids (BAs). Three commonly used types of bariatric procedures, laparoscopic sleeve gastrectomy (LSG) (without creation of a bile loop), Roux-en-Y gastric bypass (RYGB), and omega-loop gastric bypass (OLGB) (with creation of shorter 100–150 cm and longer 200–280 cm bile loops, respectively), differ in their effects on glycemic control. The aim of the study was to compare the effects of various bariatric procedures on serum BA concentration and glucose homeostasis.

Methods

Serum BAs in 26 obese patients were determined by liquid chromatography-mass spectrometry prior to bariatric surgery, as well as 4 days and 3 months thereafter.

Results

Four days after the surgery, serum concentrations of BAs in LSG and OLGB groups were similar as prior to the procedure, and a slight decrease in serum BAs was observed in the RYGB group. Serum BA level in the LSG group remained unchanged also at 3 months after the surgery, whereas a significant 0.5- and 3-fold increase in this parameter was noted in the RYGB and OLGB groups, respectively. Serum concentration of BAs correlated positively with the length of the bile loop (R?=?0.47, p?<?0.05).

Conclusion

The evident improvement of glycemic control observed 3 months after OLGB might be associated with a postoperative increase in serum BAs, resulting from their better absorption from the longer bile loop. However, the changes in serum BAs probably had little or no impact on insulin sensitivity improvement at 4 days post-surgery.

     

Characterizing Readmissions After Bariatric Surgery

Introduction

Readmissions are an important quality metric for surgery. Here, we compare characteristics of readmissions across laparoscopic Roux­en-Y gastric bypass (LRYGB), sleeve gastrectomy (LSG), and adjustable gastric band (LAGB).

Methods

Demographic, intraoperative, anthropometric, and laboratory data were prospectively obtained for 1775 patients at a single academic institution. All instances of readmissions within 1 year were recorded. Data were analyzed using STATA, release 12.

Results

For the 1775 patients, 113 (6.37 %) were readmitted. Mean time to readmission was 52.1 days. Of all the readmissions, 64.6 % were within 30 days, 22.1 % from 30 to 90 days, 1.77 % from 90 to 180 days, and 11.5 % from 180 to 365 days. Incidence of 30-day readmissions varied across surgeries (LRYGB: 7.17 %; LAGB: 3.05 %; LSG: 4.25 %, p?=?0.04). Time to readmission varied as well, with 90.0 % of LSG and 80.0 % of LABG patients within the first 30 days, versus 60.8 % of LRYGB (p?=?0.02). The most common causes of readmissions were gastrointestinal issues related to index procedure (34.5 %) and did not vary across surgeries. In multivariable logistic regression, index hospital length of stay (LOS) was associated with readmission (OR?=?1.07, 95 % CI 1.02–1.13, p?=?0.01).

Conclusions

Readmissions after bariatric surgery are associated with high index hospital LOS, and a measureable proportion of procedure-related readmissions can occur up to 1 year, especially for LRYGB.

     

Discharge Disposition After Bariatric Surgery

Weight loss continues for extended time post-bariatric surgery; thus, discharge destination is an important factor to consider when examining outcomes of surgery. The Agency for Healthcare Research and Quality State Inpatient Database was utilized to identify patients with bariatric surgery and to determine factors associated with and predictive of home discharge. Patients that were discharged home had shorter length of stays, lower total hospital costs, fewer chronic conditions, and lower readmission rates. Factors predictive of discharge were identified. Being discharged home could be associated with characteristics vital to patient’s long-term weight loss. It is imperative to focus on factors predictive of home discharge in order to reap the most beneficial outcomes of surgery.     

Bone Metabolism After Bariatric Surgery

Bariatric surgery is a popular and effective treatment for severe obesity but may have negative effects on the skeleton. This review summarizes changes in bone density and bone metabolism from animal and clinical studies of bariatric surgery, with specific attention to Roux‐en‐Y gastric bypass (RYGB), adjustable gastric banding (AGB), and sleeve gastrectomy (SG). Skeletal imaging artifacts from obesity and weight loss are also considered. Despite challenges in bone density imaging, the preponderance of evidence suggests that bariatric surgery procedures have negative skeletal effects that persist beyond the first year of surgery, and that these effects vary by surgical type. The long‐term clinical implications and current clinical recommendations are presented. Further study is required to determine mechanisms of bone loss after bariatric surgery. Although early studies focused on calcium/vitamin D metabolism and mechanical unloading of the skeleton, it seems likely that surgically induced changes in the hormonal and metabolic profile may be responsible for the skeletal phenotypes observed after bariatric surgery. © 2014 American Society for Bone and Mineral Research.     

Improvement of Nonalcoholic Fatty Liver Disease After Bariatric Surgery in Morbidly Obese Chinese Patients

Background

Obesity is a risk factor for nonalcoholic fatty liver disease (NAFLD), which appears to improve after weight loss induced by bariatric surgery in Western countries. The present study aims to determine the alterations of clinical measurements and liver histology of NAFLD after bariatric surgery in morbidly obese Chinese patients.

Methods

Between November 2006 and December 2007, 21 morbidly obese patients receiving intra-operative liver biopsy and follow-up liver biopsy 1?year after laparoscopic Roux-en-Y gastric bypass were enrolled. NAFLD activity score (NAS) and fibrosis stage were histologically evaluated.

Results

The mean body mass index fell from 43.8?±?7.5 to 28.3?±?4.6?kg/m² (P?P?P?<?0.01), but not aspartate aminotransferase (P?=?0.66). Histological improvement was noted in NAS (P?P?P?P?=?0.02). Pre-operatively, 4 (19.0%), 11 (52.4%), and 6 (28.6%) patients were found to have NAS ?R5, 3 or 4, and ?Q2, respectively. All patients had NAS ?Q2 after surgery. Fibrosis stage also showed significant improvement (P?Conclusions Bariatric surgery can achieve a dramatic improvement of NAFLD both biochemically and histologically in morbidly obese Chinese patients.     

Alcohol Use Disorders After Bariatric Surgery

Background

The increased incidence of alcohol use disorders (AUD) after bariatric surgery has been proposed despite limited empirical support. We sought to determine the prevalence of current and lifetime AUD and other Axis I diagnoses in patients who have undergone bariatric surgery, and to test the hypothesis that greater weight loss is associated with a higher incidence of AUD following surgery.

Methods

Individuals who underwent bariatric surgery between 2004 and 2007 were recruited for inclusion in the study. The diagnosis of current and lifetime AUD and other Axis I disorders was assessed using the Structured Clinical Interview for DSM-IV.

Results

A total of 51 individuals were included. The prevalence of lifetime and current AUD was 35.3% and 11.8%, respectively. No associations were found between weight loss following surgery and the development of an AUD or other Axis I diagnoses. Significantly more current AUD was reported in (1) individuals with a lifetime history of AUD compared to those without a lifetime AUD (p?p?Conclusions Individuals undergoing bariatric surgery were found to have a lifetime prevalence of AUD comparable to the general population. Although weight loss was not associated with the development of an AUD following surgery, individuals with a lifetime history of AUD may be at increased risk for relapsing to alcohol use after surgery. All instances of current AUD were identified in individuals undergoing RYGB as opposed to LAGB.     

Differential Changes in Exercise Performance After Massive Weight Loss Induced by Bariatric Surgery

Background

Exercise performance and pulmonary function are often impaired in severely obese subjects. Bariatric surgery represents the most effective therapy for severe obesity, but data on changes in exercise performance after massive weight loss induced by bariatric surgery have rarely been assessed so far.

Methods

Exercise performance was obtained by bicycle spiroergometry in 18 severely obese patients before and at least 1 year after bariatric surgery. Additionally, pulmonary function was assessed by spirometry.

Results

BMI was reduced from 46.3?±?1.6 to 33.5?±?1.4 kg/m² after surgery. Pulmonary function (forced expiratory volume within 1 s; inspiratory vital capacity) improved after weight loss (both p?≤?0.01). At peak exercise, heart rate (HR) peak, absolute oxygen uptake (VO₂) peak, and load peak did not differ between both assessments (all p?>?0.25). However, relative (related to actual body weight) VO₂ peak and workload peak were higher after than before surgery (both p?≤?0.005), while gross efficiency peak and ventilatory equivalent peak remained unchanged (both p?>?0.30). At anaerobic threshold (AT), patients showed lower HR AT and absolute VO₂ AT after than before surgery (both p?<?0.05), while absolute workload AT did not differ (p?=?0.58). In turn, relative VO₂ AT did not change (p?=?0.30), whereas relative workload AT was higher after surgery (p?=?0.04). Also, ventilatory efficiency AT and gross efficiency AT tended to be improved (both p?=?0.08). Before surgery, the patients performed 27.0 % of VO₂ peak above their AT, while this fraction increased to 35.3 % (p?=?0.006).

Conclusions

Results indicated differential changes in exercise performance, with the relative but not the absolute peak performance being improved after massive weight loss. Interestingly, anaerobic exercise tolerance was markedly improved after surgery.     

Validation of Limited Sampling Strategy for Estimation of Mycophenolic Acid Exposure During the First Year After Heart Transplantation

Background

Individualization of mycophenolate mofetil (MMF) dosing based on mycophenolic acid (MPA) therapeutic drug monitoring may minimize the risk of organ transplant rejection. The MPA area under the 12-hour concentration–time curve (MPA-AUC_0–12h) is a more powerful predictor of rejection than are MPA trough levels. Measurement of MPA-AUC_0–12h, however, is difficult and clinically impractical. The limited sampling strategy (LLS) has been proposed to overcome this problem.

Objective

To validate the predictive performance of MPA LSS algorithms previously published for heart transplant (HTx) recipients (initial group) when applied to a new independent group of 29 HTx recipients (validation group) during the first year after transplantation.

Patients and Methods

In a previous study, we established 2 algorithms using a LSS in HTx recipients: (1) 5.568 + 0.902 × C_1.25 + 2.022 × C₂ + 4.594 × C₆ and (2) 3.8 + 1.025 · C_1.25 + 1.819 × C₂ + 1.566 × C₄ + 3.479 × C₆. Agreement between abbreviated AUC and the full AUC_0–12h was tested using the Bland-Altman method. The validation group was used to test and assess bias and precision.

Results

The 2 LSS algorithms used predicted the corresponding MPA-AUC_0–12h with a mean bias of −4.85% and −3.6% and mean precision of 15.9% and 14%, respectively.

Conclusions

The MPA-AUC_0–12h obtained using the LSS may be useful to guide clinical management and dosing. This study prospectively validates 2 algorithms for calculation of MPA-AUC_0–12h using an LSS calculated in HTx recipients. Bias and precision values suggest that our algorithms could be used for MPA therapeutic drug monitoring predictions in HTx recipients who share the same characteristics.     

Changes in Bone Mineral Density During the First Year of Dialysis Treatment

International Urology and Nephrology -     

Trocar Port Hernias After Bariatric Surgery

Background

Laparoscopic bariatric surgery is increasingly being performed worldwide. It is estimated that trocar port hernias occur more often in obese patients due to their obesity and because the ports are not closed routinely. The aim of the present study was to analyze the incidence, risk factors, and management of patients with trocar port hernias after laparoscopic bariatric surgery.

Methods

All patients who were operated between 2006 and 2013 were included. During the study period, the trocar ports were not closed routinely. All patients who had any symptomatic abdominal wall hernia during follow-up were included.

Results

Overall, 1524 laparoscopic bariatric procedures were performed. There were 1249 female (82 %) and 275 male (18 %) patients. The mean age was 44 years, and median body mass index was 43 kg/m². Patients underwent laparoscopic Roux-en-Y gastric bypass (LRYGB) (n?=?859), laparoscopic adjustable gastric banding (LAGB) (n?=?364), laparoscopic sleeve gastrectomy (LSG) (n?=?68), revisional surgery (n?=?226), and other procedures (n?=?7). Three hundred and one patients (20 %) had one or more postoperative complications and the overall mortality was 0.3 % (four patients). There were 14 patients (0.9 %) with an abdominal wall hernia, of which eight (0.5 %) had a trocar port hernia, three (0.2 %) an incisional hernia from other previous surgery, and three (0.2 %) an umbilical hernia. Gender, age, BMI, smoking, type II diabetes, procedure type, complications, and weight loss were not associated with the occurrence of abdominal wall hernias.

Conclusions

Trocar port hernias after bariatric surgery occur seldom if the trocar port is not routinely closed.