Perioperative changes of procalcitonin levels in patients undergoing liver transplantation

BACKGROUND

Severe sepsis is a life-threatening complication after liver transplantation (LT) that can be difficult to diagnose and appropriately treat after LT because of patients being treated with immunosuppressants. The present study examines perioperative changes in serum procalcitonin (PCT), a specific marker of systemic bacterial infection, and determines the value of PCT as a diagnostic tool for bacteremia or rejection.

METHODS

Perioperative serum PCT levels were prospectively assessed in 104 consecutive adult patients undergoing LT (living-donor LT, n = 90; deceased-donor LT, n = 14) between May 2010 and August 2012.

RESULTS

Serum PCT levels remarkably increased soon after LT and gradually decreased thereafter, but were not increased in patients diagnosed with cytomegalovirus infection or acute cellular rejection. Serum PCT levels in patients who underwent deceased-donor LT were significantly higher than in those who underwent living-donor LT until postoperative day (POD) 7. Serum PCT levels were significantly higher in patients with bacteremia than in those without bacteremia after POD 14. In patients with post-transplant bacteremia, PCT levels increased again after POD 7 in patients who died within 3 months of LT, while levels remained low after POD 7 in patients who were alive. A positive predictive value of 83.3% for bacteremia and a negative predictive value of 97.4% were obtained at PCT cutoffs of 2.0 and 0.5 ng/mL, respectively.

CONCLUSION

Serum PCT measurement, using appropriate cutoff values, could help diagnose severe infection, and might be able to differentiate bacteremia from acute cellular rejection.

Structural changes in dermal collagen and oxidative stress levels in the skin of Japanese overweight males

OBJECTIVE

It has been reported that obese people have poorly organized dermal collagen structure because of the degradation of collagen fibers, which is caused by an increase in oxidative stress levels associated with the hypertrophy of subcutaneous adipose cells. However, it is unclear whether an increase in oxidative stress levels caused by the accumulation of subcutaneous adipose tissue and a change in the dermal structure also occur in overweight and obese Japanese people. The objectives of this study are to identify structural changes that occur in the dermis and to measure the levels of oxidative stress in Japanese overweight males.

METHODS

The overweight group included 43 Japanese male volunteers aged between 25 and 64 years and with a body mass index (BMI) of ≥25 and <30. The control group included 47 male volunteers aged between 22 and 64 years and with BMI of <25. The 20-MHz Dermascan C® ultrasound scanner with software for image analyses was used. Echogenicity of the upper and lower dermis was measured. The mRNA expression level of heme oxygenase-1 (HMOX1) in hair follicles was quantitatively analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) and was used as a marker of oxidative stress. Ultrasonographic imaging and collection of hair follicles were performed at the same site on the thigh, abdomen, and upper arm.

RESULTS

The HMOX1 mRNA expression level in the abdomen and thigh was significantly lower in the overweight group than in the control group. Moreover, the echogenicity of the upper dermis of the abdomen and the lower dermis of the abdomen and thigh was significantly lower in the overweight group than in the control group.

CONCLUSION

We detected an increase in oxidative stress levels and a decrease in the density of dermal collagen at the same site on the thigh, abdomen, and upper arm of Japanese overweight males. These findings suggest the fragility of the dermis of Japanese overweight males, which might have been caused by the accumulation of subcutaneous adipose tissue.

Section 7. A new therapeutic strategy on portal flow modulation that increases donor safety with good recipient outcomes

The goal of this study was to examine whether the lower limit of the graft-to-recipient weight ratio (GRWR) can be safely reduced to make better use of the left lobe graft in adult-to-adult living donor liver transplantation in combination with portal pressure control. Beginning December 2007, the acceptable limit for GRWR was lowered to ≥0.7% and by April 2009, it was further lowered to ≥0.6%. A portal pressure control program targeting a final portal pressure <15 mm Hg was also introduced. The donor complication rate decreased from 13.8% to 9.3%. The overall survival of recipients with GRWR <0.8% did not differ from recipients with a GRWR ≥0.8%. In conclusion, the lower limit of the GRWR can be safely reduced to 0.6% using a left lobe graft in adult-to-adult living donor liver transplantation in combination with portal pressure control.

Influence of cytochrome P450 (CYP) 3A4*1G polymorphism on the pharmacokinetics of tacrolimus, probability of acute cellular rejection, and mRNA expression level of CYP3A5 rather than CYP3A4 in living-donor liver transplant patients

Association between cytochrome P450 (CYP) 3A4*1G genotype of donors (n=412) and/or recipients (n=410), and the pharmacokinetics of tacrolimus and the risk of acute cellular rejection was examined in Japanese living-donor liver transplant patients between 2004 and 2011. The concentration/dose (C/D) ratio of tacrolimus in patients carrying graft liver with CYP3A4*1/*1 was significantly higher during 7 d after surgery than in that with CYP3A4*1/*1G (214 vs. 157 [ng/mL]/[mg/kg/day], p<0.01). After postoperative day 8, no significant difference was observed among CYP3A4*1G genotypes in the graft liver. However, the C/D ratio in CYP3A4*1/*1 of the intestine was significantly higher than that in CYP3A4*1G/*1G for 5 weeks after surgery (postoperative days 1-14; p<0.001, postoperative days 15-35; p<0.01). During postoperative days 14 and 26, acute cellular rejection incidences tended to be lower in the patients with graft liver carrying the CYP3A4*1/*1 allele than in the patients carrying CYP3A4*1G allele (8.7% vs. 14.6%, p=0.0973). However, CYP3A4*1G in the intestine had almost no effect on the incidence of rejection (9.9% in CYP3A4*1/*1 vs. 12.5% in CYP3A4*1G allele, p=0.4824). CYP3A4*1G was significantly related to mRNA expression of CYP3A5 rather than of CYP3A4 in the graft liver and intestine and was strongly linked with the CYP3A5*1. Thus, we elucidated that CYP3A4*1G genotype in the intestine was an important indicator of the pharmacokinetics of tacrolimus, whereas this genotype in the graft liver tended to influence the frequency of acute cellular rejection after transplantation.

Luminescence-based assay to screen preservation solutions for optimal ability to maintain viability of rat intestinal grafts

BACKGROUND

Segmental intestinal transplantations from living, genetically related donors provide advantages compared with those from cadaveric subjects. However, successful preservation during ischemic cold storage is critical for living donor grafts. Thus, the development of preservation solutions that maintain graft viability is essential for success. Herein we have reported application of a cell-based viability assay in multiwell plates to assess the effectiveness of various solutions to preserve intestinal grafts.

METHODS

Freshly isolated intestinal chips from luciferase transgenic rats were placed in 96-well tissue culture plates for incubation at 4°C for 24 hours in various preservation solutions: ET-Kyoto (ET-K), University of Wisconsin (UW) solution, Euro-Collins (EC) solution, histidine-tryptophan-ketoglutarate (HTK) solution, lactated Ringer's (LR) solution, or saline.

RESULTS

As indicated by a higher level of luminescence, intestinal chips preserved in UW, HTK, or ET-K solution contained more viable cells, than those preserved in EC, LR, or saline solution. After exposure to the preservation solutions for 1 hour, the mucosal layer chips showed lower cell viability than the muscle layer chips.

CONCLUSION

Our data demonstrated that ET-K and UW solutions used together with intestinal chips of Luciferase transgenic rat and in vivo imaging provided optimal viability during ischemic cold storage prior to transplantation. Further development of preservation conditions to minimize the loss of viability of intestinal grafts before clinical transplantation is essential to improve outcomes.

Section 12. Living donor liver transplantation for patients with high model for end-stage liver disease scores and acute liver failure

Living donor liver transplantation (LDLT) for patients with high model for end-stage liver disease score and acute liver failure patients have little or not gained any substantial following among Western centers because of the "donor high risk-low recipient benefit scenario" that puts the donor at a significant risk against the survival odds for a recipient who is receiving a partial graft and considered marginal by Western standards. In most Asian countries, there is sometimes no other source of live graft but a willing live liver donor. There are individual Asian center reports that conclude that LDLT has comparable outcome to deceased donor liver transplant. However, the outcomes of a large number of patients after undergoing adult LDLT for high model for end-stage liver disease scores and acute liver failure at a single center have not been investigated. Here in, we present our experience with such subgroup of patients undergoing LDLT.

Chronic rejection associated with antiviral therapy for recurrent hepatitis C after living-donor liver transplantation

BACKGROUND

Chronic rejection (CR) has been reported to be associated with antiviral therapy for recurrent hepatitis C in liver transplant (LT) recipients. The aims of this study were to clarify the details of antiviral therapy-associated CR after living-donor liver transplantation (LDLT) and to identify the factors associated with CR.

METHODS

A retrospective chart review was performed on 125 recipients who had received antiviral therapy for recurrent hepatitis C after LDLT between January 2001 and September 2012. The characteristics of patients who developed CR during or within 6 months after antiviral therapy were compared with those of 76 patients who did not develop CR despite receiving antiviral therapy for more than 1 year.

RESULTS

Seven of 125 (6%) patients developed CR during or within 6 months after the end of antiviral therapy. CR was diagnosed after a median (range) of 9 (1-16) months of antiviral therapy. In five patients, rejection progressed rapidly and resulted in death within 3 months after diagnosis. Analysis revealed two significant factors associated with CR: reduction of the immunosuppressant dose during antiviral therapy and a low fibrosis score as the indication for antiviral therapy.

CONCLUSIONS

CR developed in association with antiviral therapy for recurrent hepatitis C after LDLT. This complication may be prevented by ensuring that the immunosuppressant dose is not reduced during antiviral therapy.

Impact of preoperative uncontrollable hepatic hydrothorax and massive ascites in adult liver transplantation

PURPOSE

Uncontrollable hepatic hydrothorax and massive ascites (H&MA) requiring preoperative drainage are sometimes encountered in liver transplantation (LT). We retrospectively analyzed the characteristics of such patients and the impact of H&MA on the postoperative course.

METHODS

We evaluated 237 adult patients who underwent LT in our institute between April 2006 and October 2010.

RESULTS

Recipients with uncontrollable H&MA (group HA: n = 36) had more intraoperative bleeding, higher Child-Pugh scores, lower serum albumin concentrations and higher blood urea nitrogen concentrations than those without uncontrollable H&MA (group C: n = 201). They were also more likely to have preoperative hepatorenal syndrome and infections. The incidence of postoperative bacteremia was higher (55.6 vs. 46.7%, P = 0.008) and the 1- and 3-year survival rates were lower (1 year: 58.9 vs. 82.9%; 3 years: 58.9 vs. 77.7%; P = 0.003) in group HA than in group C. The multivariate proportional regression analyses revealed that uncontrollable H&MA and the Child-Pugh score were independent risk factors for the postoperative prognosis.

CONCLUSIONS

Postoperative infection control may be an important means of improving the outcome for patients with uncontrollable H&MA undergoing LT, and clinicians should strive to perform surgery before H&MA becomes uncontrollable.

[Specific considerations in living-donor liver transplantation]

INTRODUCTION

Due to the limited number of cadaver donors, adult living liver donor transplantation became an alternative for liver transplantation. During living liver donor transplantation, the safety and uncomplicated recovery of the donor are as important as the appropriate volume and weight of the donated graft. The middle hepatic vein causes a significant dilemma, due to the special anatomical position. The reconstruction of the middle hepatic vein branches supplying S5, S8 is suggested when the anatomically right liver lobe is transplanted.

AIM

The aim of the present study was to investigate the requirements of the reconstruction of middle hepatic vein and to give an accurate description about the discrepancy between the portal vein in- and outflow.

METHOD

The authors analyzed the liver anatomic characteristics of 130 donors undergoing living liver donor transplantation with the use of MeVis software. The so-called porto-hepatic disparity index (shift) was introduced.

RESULTS

The right hepatic vein was dominant in 64.6% of all cases, while the left hepatic vein was never observed to be dominant. The territories of V5 and V8 were responsible for the 33.2±8.9% of the right hepatic lobe area. The correlation between portal venous territory and vein dominancy were as follows: R2 = 0.7811 in the left liver lobe; R² = 0.5463 in the area of middle hepatic vein and R² = 0.5843 in the case of the right hepatic vein. The average value of the shift was 28.2%.

CONCLUSIONS

The differences among the pattern of portal in- and hepatic outflow is an important issue that should be taken into consideration when deciding the necessity for reconstruction of the middle hepatic vein.

Portocaval shunt for hepatocyte package: challenging application of small intestinal graft in animal models

In developing therapeutic alternatives to liver transplantation, we have used the strategy of applying a small intestinal segment as a scaffold for hepatocyte transplantation and also as a portocaval shunt (PCS) system to address both liver dysfunction and portal hypertension. The aim of this study was to investigate the feasibility of such an intestinal segment in animal models. Hepatocytes isolated from luciferase-transgenic Lewis rats were transplanted into jejunal segments of wild-type Lewis rats with mucosa removal without PCS application. Luciferase-derived luminescence from transplanted hepatocytes was stably detected for 30 days. Then, we performed autologous hepatocyte transplantation into the submucosal layer of an isolated and vascularized small intestinal segment in pigs. Transplanted hepatocytes were isolated from the resected left-lateral lobe of the liver. On day 7, hepatocyte clusters and bile duct-like structures were observed histologically. To create an intestinal PCS system in pigs, an auto-graft of the segmental ileum and interposing vessel graft were anastomosed to the portal vein trunk and inferior vena cava. However, thrombi were observed in vessels of the intestinal PCSs. We measured the correlation between infusion pressure and flow volume in whole intestines ex vivo in both species and found that the high pressure corresponding to portal hypertension was still insufficient to maintain the patency of the intestinal grafts. In conclusion, we demonstrated the feasibility of the small intestine as a scaffold for hepatocyte transplantation in rat and pig models, but PCS using an intestinal graft failed to maintain patency in a pig model.

Usefulness of endoscope guided transabdominal ultrasonography in T staging of colorectal cancer

BACKGROUND/AIMS

We investigated the efficacy of endoscope guided transabdominal ultrasonography (EGTUS) for the evaluating the depth of colorectal cancer invasion.

METHODOLOGY

The subjects were 52 patients with colon cancer and 30 patients with rectal cancer who underwent transabdominal US and curative surgery. During endoscopy, we applied transabdominal US by filling the area around the tumor with de-gassed water. The accuracy of depth invasion assessment using EGTUS was compared with that using endoscopic, computed tomography (CT), surgical or histological findings.

RESULTS

The tumor detection rate was 75.6% (62/82), 88.5% (46/52) for colon cancer and 53.3% (16/30) for rectal cancer. The diagnostic accuracies of EGTUS, endoscopic, CT and surgical findings were 87.1% (54/62), 73.2% (60/82), 66.7% (46/69), 65.9% (54/82), respectively. The diagnostic accuracy of EGTUS was 100% (2/2), 66.7% (4/6), and 90.0% (44/49) for T1, T2 and T3 cancer, respectively.

CONCLUSION

The results suggest that EGTUS is useful for evaluating preoperative T staging of colorectal cancer.

Usefulness of the Kyoto criteria as expanded selection criteria for liver transplantation for hepatocellular carcinoma

BACKGROUND

Previously, we proposed expanded selection criteria for liver transplantation (LT) for hepatocellular carcinoma (HCC), the Kyoto criteria, involving a combination of tumor number ≤10, maximal diameter of each tumor ≤5 cm, and serum des-gamma-carboxy prothrombin levels ≤400 mAU/mL, and we have used these criteria since January 2007. In the present study, the usefulness of the criteria was validated prospectively as well as retrospectively.

METHODS

One hundred ninety-eight patients with HCC who underwent living donor LT (LDLT) from February 1999 through December 2011 were enrolled in this study. Overall survival and recurrence rates were investigated in patients classified according to the Kyoto criteria, the Milan criteria, or previous treatments for HCC. Tumor biological aggressiveness, including microvascular invasion and histologic differentiation, according to selection criteria was also examined.

RESULTS

The 5-year overall survival for patients within the Kyoto criteria (n = 147; 82%) was greater than that for the 49 patients exceeding them (n = 49; 42%; P < .001). The 5-year recurrence rate for patients within the Kyoto criteria (4.4%) was less than that for patients exceeding them (51%; P < .001). Intention-to-treat analysis of the 62 patients who underwent LDLT after implementation of the Kyoto criteria showed that the 5-year overall survival rate and the recurrence rate were 82% and 7%, respectively. Tumor biology was significantly less aggressive in patients within the Kyoto criteria.

CONCLUSION

The Kyoto criteria are useful expanded criteria for LDLT for HCC and could help to achieve favorable outcomes.