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71.

Background

Although several studies have been conducted on the patterns of recurrence in resected perihilar cholangiocarcinoma, they have many limitations. The aim of this study was to investigate recurrence after resection and to evaluate prognostic factors on the time to recurrence and recurrence-free survival.

Methods

Consecutive patients who underwent curative-intent resection of perihilar cholangiocarcinoma between 2001 and 2012 were reviewed retrospectively. The Cox proportional hazards model was used for multivariable analysis.

Results

In the study period, 402 patients underwent resection of perihilar cholangiocarcinoma (R0, n?=?340; R1, n?=?62). Radial margin positivity (n?=?43, 69%) was the most common reason for R1 resection. The median follow-up of survivors was 7.4 years. The cumulative recurrence probability was higher in R1 than in R0 resection (86% vs 57% at 5 years, P?<?.001). Seventeen R0 patients had a recurrence over 5 years after resection. There was no difference in median survival time after recurrence between R0 and R1 resection (10 vs 7 months). The proportion of isolated locoregional recurrence was higher in R1 than in R0 resection (37% vs 16%, P?<?.001), whereas the proportion of distant recurrence was similar. In R0 resection, the independent prognostic factors for time to recurrence and recurrence-free survival were microscopic venous invasion and lymph node metastasis.

Conclusion

More than half of patients with perihilar cholangiocarcinoma experience recurrence after R0 resection. These recurrences occur frequently within 5 years but occasionally after 5 years, which emphasizes the need for close and long-term surveillance. Adjuvant strategies should be considered, especially for patients with nodal metastasis or venous invasion even after R0 resection.  相似文献   
72.

Background

Parathyroidectomy (PTx) decreases the mortality rate of refractory secondary hyperparathyroidism (rSHP) due to chronic kidney disease. A consensus regarding which techniques of PTx are associated with better outcomes is not available. The aims of this study are to evaluate the clinical and laboratory evolution of 49 hemodialysis patients with rSHP who underwent PTx using different techniques.

Methods

Patients underwent subtotal PTx (sub-PTx) or total PTx with autotransplantation (AT) of 45 (PTx-AT45) or 90 parathyroid fragments (PTx-AT90) and were followed for 12 months. We analyzed the expression of proliferating cell nuclear antigen (PCNA), calcium-sensing receptor (CasR), vitamin D receptor (VDR), fibroblast growth factor receptor-1 (FGFR1), sodium-dependent phosphate cotransporter-1 (PIT1), and Klotho in parathyroid glands.

Results

Baseline median serum intact parathyroid hormone (iPTH) levels were 1,466 (1,087–2,125) pg/mL; vascular calcification scores correlated with serum iPTH (r?=?0.529; P?=?.002) and serum phosphate levels (r?=?0.389; P?=?.028); and Klotho expression was negatively correlated with serum phosphate levels (r?=??0.4; P?=?.01). After 12 months, serum iPTH and alkaline phosphatase levels were significantly controlled in all groups, as was bone pain. The proportions of patients with serum iPTH levels within the ranges recommended by Kidney Disease: Improving Global Outcomes were similar among the treatment groups. During the hungry bone disease (HBS), patients received 3,786?g (1,412–7,580) of elemental calcium, and a trend toward a positive correlation between the cumulative calcium load at the end of follow up and VC score post-PTx was noted (r?=?0.390; P?=?.06). Two cases evolved to clinically uncontrolled hyperparathyroidism in the sub-PTx group. The expression patterns of PCNA, VDR, CasR, PIT1, FGFR1, and Klotho in parathyroid glands did not correlate with serum systemic iPTH levels or the duration of HBS.

Conclusions

All 3 operative techniques were effective at controlling rSHP, both in clinical and laboratory terms. Neither the quantity nor quality of parathyroid fragments influenced serum systemic iPTH and AT-iPTH levels. The cumulative calcium load appeared to correlate with the VC score and may have affected its progression. The effects of phosphate restriction on Klotho expression in human parathyroid glands and the subsequent decrease in FGF23 resistance must be addressed in further studies.  相似文献   
73.

Background

In the Model for End-Stage Liver Disease (MELD) system, patients with “MELD exceptions” points may have unfair privilege in the competition for liver grafts. Furthermore, organ distribution following identical ABO blood types may also result in unjust organ allocation. The aim of this study was to investigate access to liver transplantation in a tertiary Brazilian center, regarding “MELD exceptions” situations and among ABO-blood groups.

Methods

A total of 465 adult patients on the liver waitlist from August 2015 to August 2016 were followed up until August 2017. Patients were divided into groups according to ABO-blood type and presence of “exceptions points.”

Results

No differences in outcomes were observed among ABO-blood groups. However, patients from B and AB blood types spent less time on the list than patients from A and O groups (median, 46, 176, 415, and 401 days, respectively; P = .03). “Exceptions points” were granted for 141 patients (30.1%), hepatocellular carcinoma being the most common reason (52.4%). Patients with “exceptions points” showed higher transplantation rate, lower mortality on the list, and lower delta-MELD than non-exceptions patients (56.7% vs 19.1% [P < .01]; 18.4% vs 38.5% [P < .01], and 2.0 ± 2.6 vs 6.9 ± 7.0 [P < .01], respectively). Patients with refractory ascites had a higher mortality rate than those with other “exceptions” or without (48%).

Conclusions

The MELD system provides equal access to liver transplantation among ABO-blood types, despite shorter time on the waitlist for AB and B groups. The current MELD exception system provides advantages for candidates with “exception points,” resulting in superior outcomes compared with those without exceptions.  相似文献   
74.

Background

Although renal function recovery of living kidney donors has been reported in a number of studies, many patients show poor recovery, and the long-term prognosis of these patients has not been well studied. In this investigation we explored the long-term prognosis of renal function in patients with chronic kidney disease (CKD) at 1 year after nephrectomy.

Methods

Patients who underwent donor nephrectomy during the period from March 2006 to April 2014, with a follow-up creatinine study at 1 year postoperatively and more than 3 years of follow-up, were included in the study. Creatinine and estimated glomerular filtration rate (eGFR, using the Modification of Diet in Renal Disease formula) before and after surgery were studied. Age, sex, history of hypertension or diabetes, body mass index, blood pressure, complete blood count, preoperative routine serum chemistry, and urine study results were reviewed.

Results

Among 841 patients who had donor nephrectomy, 362 were included in the study. There were 111 patients (30.6%) with eGFR <60 mL/min/1.73 m2 at 1 year postsurgery, and the median follow-up period was 62.8 months (interquartile range [IQR] 42.0–86.3 months). The maximum eGFR after 3-year follow-up was studied, and 48 patients (43.2%) never recovered eGFR to >60 mL/min/1.73 m2. Age, history of hypertension, preoperative eGFR, and eGFR at 1 year were predictive factors at univariate analysis. Multivariate analysis of these factors was studied, and age (52.5 [IQR 47–55.7] vs 47 [IQR 7–53] years, odds ratio [OR] 1.1, 95% confidence interval [CI] 1.02–1.15, P = .007), history of hypertension (16.7% vs 1.6%, OR 10.0, 95% CI 1.09–92.49, P = .042), and eGFR at 1 year (53.9 [IQR 50.3–56.0] vs 57.0 [IQR 54.2–58.4] mL/min/1.73 m2, OR 0.8, 95% CI 0.72–0.92, P = .002) remained as significant risk factors.

Conclusion

Of all living donors, 15.7% had CKD after >3 years of follow-up. Close observation is warranted when donors have CKD after 1 year follow-up, as 43.2% fail to recover renal function. Patients who are older, have a history of hypertension, and have low eGFR at 1-year follow-up are especially at risk.  相似文献   
75.

Background

The effect of altered parathyroid hormone metabolism in renal insufficiency on intraoperative parathyroid hormone monitoring during parathyroidectomy is not well known. This study evaluates operative outcomes in patients undergoing parathyroidectomy guided by intraoperative parathyroid hormone monitoring for primary hyperparathyroidism with mild and moderate renal insufficiency.

Methods

A retrospective review of prospectively collected data in 604 patients with sporadic primary hyperparathyroidism undergoing parathyroidectomy guided by intraoperative parathyroid hormone monitoring was performed. Patients were stratified by stage of chronic kidney disease (CKD); those with overt secondary hyperparathyroidism (CKD stages IV and V) were excluded. Rates of bilateral neck exploration, multiglandular disease, and long-term operative outcomes, including success, failure, and recurrence were compared.

Results

Of the 604 patients, 38% (230/604) had normal renal function or stage I CKD, 44% (268/604) had stage II CKD, and 18% (106/604) had stage III CKD. Overall, there were no differences in the rates of bilateral neck exploration or multiglandular disease or in rates of operative success, failure, or recurrence in patients with normal renal function and stages I to III CKD.

Conclusion

Parathyroidectomy guided by intraoperative parathyroid hormone monitoring is performed with high operative success uniformly in primary hyperparathyroidism patients with mild and moderate renal insufficiency with outcomes similar to those with normal renal function.  相似文献   
76.

Background

Single antigen bead assay (SAB) is a sensitive method for detecting HLA antibodies, but it does not specifically identify clinically relevant subsets. Recently, a new assay has been developed for detection of C3d bound to HLA antibody-antigen complex. We evaluated the C3d assay regarding its correlation with SAB in renal patients.

Methods

A total of 138 serum samples from 109 sensitized patients were tested in parallel by SAB and C3d assay for detection of HLA class I antibodies. The relationship between C3d assay and SAB was analyzed for the numbers and median fluorescent intensity (MFI) values of the identified antibodies.

Results

Of the 138 samples, 137 were positive on SAB; of the 137 SAB-positive samples, 76 were positive on C3d assay. A total of 3748 and 685 antibodies were identified by the SAB and the C3d assay, respectively. The maximal MFI values of the SAB in the 76 samples that were C3d assay-positive were significantly higher than those of the 61 samples that were C3d assay-negative (P < .05), with the median values of 17,057 and 6066, respectively. Only 11 (0.4%) of the 2905 antibodies with MFI < 10,000 on SAB vs 501 (59.4%) of the 843 antibodies with MFI > 10,000 on SAB were identified by C3d assay with MFI > 1000.

Conclusions

The C3d assay positivity seems to be dependent on its MFI value on SAB. Further studies are needed to ascertain the clinical significance of C3d positivity by itself.  相似文献   
77.
Uterus transplantation (UTx) has become an alternative to gestational surrogacy and adoption for women with uterine factor infertility (UFI). Brännström et al achieved the first human delivery after UTx in 2014, and to date a total of 8 babies have been born after UTx from living donors. This outcome has attracted much attention worldwide, and many countries are now preparing for UTx.There are an estimated 60,000 women of reproductive age with UFI in Japan, and these patients cannot have biological children because gestational surrogacy is forbidden in Japan. We have performed UTx research from 2009 using cynomolgus macaque, in preparation for clinical application of UTx for these patients to have a child, and we have accumulated a large amount of data. However, the UTx procedure still has many medical, ethical, and social issues that require discussion prior to clinical application. The Japan Society for Uterus Transplantation was established in 2014 for further discussion of these issues in Japan.UTx is still in the experimental stage overseas, and the safety and efficacy remain unclear, despite several clinical applications. Despite the many issues to be resolved, this organ transplantation technology will provide new hope for women with UFI, and further development of the technology is important for future reproductive and transplant medicine.In this article, we summarize the current status of UTx and the situation regarding future clinical application in Japan.  相似文献   
78.
Treatment with mammalian target of rapamycin inhibitors (mTORi) has been associated with an increased incidence of proteinuria after kidney transplantation as compared to other immunosuppressive agents. Proteinuria after mTORi use may occur in different clinical conditions and the precise mechanism remains unclear. The objective of this study was to investigate the related risk factors for proteinuria after mTORi treatment in kidney transplant recipients. This retrospective observational study population consisted of kidney transplant recipients followed up in a medical center in Southern Taiwan from January 1999 to April 2016. The baseline characteristics and transplantation-related profiles were collected at the time of enrollment. We examined risk factors for mTORi-associated proteinuria using a multivariate logistic regression analysis. P < .05 was considered as statistically significant. Hyperlipidemia and obesity at the initiation of mTORi treatment were strong predictors for proteinuria. Earlier identification of these risk factors may assist physicians in deciding the best candidate for mTORi conversion in order to optimize transplantation outcomes.  相似文献   
79.

Background

Comorbid conditions are important in the survival of kidney transplant recipients. The weights assigned to comorbidities to predict survival may vary based on the type of index disease and advances in the management of comorbidities. We aimed to develop a modified Charlson comorbidity index (CCI) in renal allograft recipients (mCCI-KT), thereby improving risk stratification for mortality.

Methods

A total of 3765 recipients in a multicenter cohort were included to develop a comorbidity score. The weights of the comorbidities, per the CCI, were recalibrated using a Cox proportional hazards model.

Results

Peripheral vascular disease, liver disease, myocardial infarction, and diabetes in the CCI were selected from the Cox proportional hazards model. Thus, the mCCI-KT included 4 comorbidities with recalibrated severity weights. Whereas the CCI did not discriminate for survival, the mCCI-KT provided significant discrimination for survival using the Kaplan-Meier method and Cox regression analysis. The mCCI-KT showed modest increases in c-statistics (0.54 vs 0.52, P = .001) and improved net mortality risk reclassification by 16.3% (95% confidence interval, 3.2–29.4; P = .015) relative to the CCI.

Conclusion

The mCCI-KT stratifies the risk for mortality in renal allograft recipients better than the CCI, suggesting that it may be a preferred index for use in clinical practice.  相似文献   
80.

Background

Although patients undergoing liver transplantation (LT) are frequently exposed to predisposing factors of atrial fibrillation (AF) such as autonomic imbalance, surgical stress, and elevated catecholamine levels, the occurrence of intraoperative AF (IOAF) has not been fully examined in LT candidates.

Methods

Data from 1059 patients who underwent adult LT from 2006 to 2010 were analyzed. Among patients with preoperative normal sinus rhythm, the incidence, prognosis, and detailed characteristics of newly developed IOAF were assessed. Their risk factors and clinical implication, including hepatic graft survival and mortality, were also examined.

Results

Thirteen (1.2%) cases of AF newly developed intraoperatively. A higher Model for End-Stage Liver Disease score (adjusted odds ratio, 1.077 [95% confidence interval, 1.015–1.143]; P = .015) and fulminant hepatic failure (adjusted odds ratio, 6.844 [95% CI, 1.944–24.096]; P = .003) were associated with its occurrence. Eight cases of newly developed AF occurred immediately after hepatic graft reperfusion; the other 3 cases occurred during the pre-anhepatic or anhepatic phase. The majority of patients (9 cases) experienced only brief episodes of AF lasting <1 hour. Despite all patients with newly developed AF eventually converting to sinus rhythm within 1 week after surgery, the episode of IOAF was independently associated with mortality (adjusted hazard ratio, 5.097 [95% confidence interval, 2.189–11.868]; P < .001) after adjustment for Model for End-Stage Liver Disease score.

Conclusions

For LT recipients, even a brief episode of newly developed IOAF seems to be an important prognosticator, regardless of AF duration.  相似文献   
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