Recipient artery dissection during extracranial-intracranial bypass surgery:Two case reports

BACKGROUND Superficial temporal artery to middle cerebral artery(STA-MCA)bypass is a valuable treatment for preventing ischemia and hemorrhage in occlusive cerebrovascular disease.Anastomosis site dissection is rarely reported among the various bypass-related complications.CASE SUMMARY In this case report,we describe two patients,who were 63-and 59-years-old with middle cerebral artery occlusion treated by STA-MCA bypass.During bypass surgery,the recipient M4 artery intima was dissected.We sacrificed the dissecting portion,and no complications occurred during the follow-up period.Postoperative brain imaging revealed improved brain perfusion.We report rare cases of recipient artery dissection located in the extracranial to intracranial bypass site,and we suggest atherosclerotic changes in the recipient artery and insufficient puncture as the causes.CONCLUSION Appropriate recipient artery selection is critical,and if dissection occurs,it is essential to sacrifice the dissecting portion quickly.

Supportive care in transplantation: A patient-centered care model to better support kidney transplant candidates and recipients

Kidney transplantation(KT),although the best treatment option for eligible patients,entails maintaining and adhering to a life-long treatment regimen of medications,lifestyle changes,self-care,and appointments.Many patients experience uncertain outcome trajectories increasing their vulnerability and symptom burden and generating complex care needs.Even when transplants are successful,for some patients the adjustment to life post-transplant can be challenging and psychological difficulties,economic challenges and social isola-tion have been reported.About 50%of patients lose their transplant within 10 years and must return to dialysis or pursue another transplant or conservative care.This paper documents the complicated journey patients undertake before and after KT and outlines some initiatives aimed at improving patient-centered care in transplantation.A more cohesive approach to care that borrows its philosophical approach from the established field of supportive oncology may improve patient experiences and outcomes.We propose the"supportive care in transplantation"care model to operationalize a patient-centered approach in transplantation.This model can build on other ongoing initiatives of other scholars and researchers and can help advance patient-centered care through the entire care continuum of kidney transplant recipients and candidates.Multi-dimensionality,multi-disciplinarity and evidence-based approaches are proposed as other key tenets of this care model.We conclude by proposing the potential advantages of this approach to patients and healthcare systems.Core Tip:Kidney transplant recipients and candidates face several uncertainties in their care journey and have several expressed unmet healthcare needs.We recommend a structured and comprehensive approach to transplant care across the entire continuum of a transplant patient’s journey similar to what has been developed in the field of oncology.The supportive care in transplantation model can operationalize patient-centered care and build on the efforts of other researchers in the field.We postulate that such a model would significantly improve care delivery and patients’experiences and outcomes and potentially decrease healthcare utilization and cost.INTRODUCTION Patients with kidney failure benefit from(KT)[1,2],and experience improved survival rates when compared with dialysis[3-6].KT studies,using validated instruments,have also consistently demonstrated that kidney transplant recipients(KTRs)experience better health-related quality of life and several improvements in other disease-specific domains when compared with dialysis[7].In countries where dialysis is out of reach for many,the diagnosis of kidney failure would be futile without KT[8].Thus,increasing KT has been a priority for the nephrology and transplant communities.This priority has been reflected in recent global trends:Of the 79 countries where data were available,the International Society of Nephrology’s Global Kidney Atlas reported that the prevalence of KTRs in 2023 was 279 per million population which represented an increase of 9.4%from the data published four years prior[8].Despite this growth,KT can be a challenging journey for many patients and it is sometimes regarded as a‘cure’,which does not conform with the reality that many patients experience[9-13].KTRs must maintain a life-long treatment regimen of medications,lifestyle changes,self-care and medical appointments[14-17].As poignantly stated by a young female transplant recipient,“I thought everything would change once I got my kidney.I thought I would be healthy again”but after experiencing multiple side effects of immunosuppressive medications and graft loss,she stated,“I am just a different kind of patient now”[18].Indeed,a significant proportion of patients experience graft failure and return to dialysis;it is estimated that over 50%return to dialysis within 10 years of KT[19-23].Patients are often not prepared for this outcome and report several psychosocial and physical ramifications of graft failure[24,25].Overall,high symptom burden,adverse effects of immunosuppressants,risk of graft rejection or failure and mortality,contribute to complex needs,vulnerability and uncertainties for patients,increasing their care needs and treatment burden[26-30].In this paper,we highlight the complex journey that KTRs and candidates undertake that can generate varied outcome trajectories and complex healthcare needs.We highlight the need for a comprehensive patient-centered approach to care and conclude with a proposal for a“supportive care in transplantation”care model.

Impact of COVID-19 on liver transplant recipients: A nationwide cohort study evaluating hospitalization, transplant rejection, and inpatient mortality

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has posed a major public health concern worldwide.Patients with comorbid conditions are at risk of adverse outcomes following COVID-19.Solid organ transplant recipients with concurrent immunosuppression and comorbidities are more susceptible to a severe COVID-19 infection.It could lead to higher rates of inpatient complications and mortality in this patient population.However,studies on COVID-19 outcomes in liver transplant(LT)recipients have yielded inconsistent findings.AIM To evaluate the impact of the COVID-19 pandemic on hospital-related outcomes among LT recipients in the United States.METHODS We conducted a retrospective cohort study using the 2019–2020 National Inpatient Sample database.Patients with primary LT hospitalizations and a secondary COVID-19 diagnosis were identified using the International Classi-fication of Diseases,Tenth Revision coding system.The primary outcomes included trends in LT hospitalizations before and during the COVID-19 pandemic.Secondary outcomes included comparative trends in inpatient mortality and transplant rejection in LT recipients.RESULTS A total of 15720 hospitalized LT recipients were included.Approximately 0.8% of patients had a secondary diagnosis of COVID-19 infection.In both cohorts,the median admission age was 57 years.The linear trends for LT hospitalizations did not differ significantly before and during the pandemic(P=0.84).The frequency of in-hospital mortality for LT recipients increased from 1.7% to 4.4% between January 2019 and December 2020.Compared to the pre-pandemic period,a higher association was noted between LT recipients and in-hospital mortality during the pandemic,with an odds ratio(OR)of 1.69[95% confidence interval(CI):1.55-1.84),P<0.001].The frequency of transplant rejections among hospitalized LT recipients increased from 0.2%to 3.6% between January 2019 and December 2020.LT hospitalizations during the COVID-19 pandemic had a higher association with transplant rejection than before the pandemic[OR:1.53(95%CI:1.26-1.85),P<0.001].CONCLUSION The hospitalization rates for LT recipients were comparable before and during the pandemic.Inpatient mortality and transplant rejection rates for hospitalized LT recipients were increased during the COVID-19 pandemic.

Optimizing growth in pediatric renal transplant recipients: An update

Growth retardation is a significant complication observed in pediatric renal transplant recipients,originating from a multifactorial etiology.Factors contributing to growth impairment encompass pre-transplant conditions such as primary kidney disease,malnutrition,quality of care,growth deficits at the time of transplantation,dialysis adequacy,and the use of recombinant human growth hormone.Additionally,elements related to the renal transplant itself,such as living donors,corticosteroid usage,and graft functioning,further compound the challenge.Although renal transplantation is the preferred renal replacement therapy,its impact on achieving final height and normal growth in children remains uncertain.The consequences of growth delay extend beyond the physi-ological realm,negatively influencing the quality of life and social conditions of pediatric renal transplant recipients,and ultimately affecting their educational and employment outcomes.Despite advancements in graft survival rates,growth retardation remains a formidable clinical concern among children undergoing renal transplantation.Major risk factors for delayed final adult height include young age at transplantation,pre-existing short stature,and the use of specific immunosuppressive drugs,particularly steroids.Effective management of growth retardation necessitates early intervention,commencing even before transplantation.Strategies involving the administration of recombinant growth hormone both pre-and post-transplant,along with protocols aimed at minimizing steroid usage,are important for achieving catch-up growth.This review provides a comprehensive outline of the multifaceted nature of growth retardation in pediatric renal transplant recipients,emphasizing the importance of early and targeted interventions to mitigate its impact on the long-term well-being of these children from birth to adolescence.INTRODUCTION Children with chronic kidney disease(CKD)endure frequent hospitalizations and ongoing treatment,which significantly affect their quality of life.One of the most noticeable effects of CKD in children is poor growth,with stunted height being a common sign of chronic malnutrition.Growth assessment involves regularly measuring weight and height/length and comparing these against z-score charts,along with other anthropometric indicators like head circumference and mid-upper arm circumference.Data from the North American Pediatric Renal Trials and Collaborative Studies(NAPRTCS)registry shows that over 35%of children enrolled had stunted growth at the time of admission,with growth impairment being more severe in younger children(58%in those aged under 1 year,compared to 22%in those aged over 12 years).Additionally,the same data revealed that growth impairment worsens as the severity of the disease increases.Although recent advances in science have enabled better outcomes for children with CKD,in resource-limited settings,numerous children are still deprived of achieving optimal growth owing to the disease and its related factors.Stunting is a key indicator of chronic growth impairment in children.A study by Wong et al[1]in the United States Renal Data System found that each SD decrease in height among children with stage V CKD is linked to a 14%increase in the risk of death[1].Similarly,research by Furth et al[2]using data from the NAPRTCS indicated that children with a height standard deviation score(SDS)of-2.5 face a relative hazard of death of 2.07.Stunting also correlates with increased hospitalizations.A study in the United States followed 1112 pediatric patients with end-stage renal disease from 1990 to 1995.It showed that children with severe or moderate growth failure had higher hospitalization rates compared to those with normal growth.Specifically,the relative risk for hospitalization was 1.14(95%CI:1.1-1.2)for those with moderate growth failure and 1.24(95%CI:1.2-1.3)for those with severe growth failure,even after adjusting for age,sex,race,cause,and duration of end-stage renal disease,and treatment type[2](dialysis or transplant).The growth of a child significantly affects his/her psychological and overall well-being as an adult.Short children are often embarrassed by peers,and it has been observed that height influences employment status,with unemployment being more prevalent among stunted individuals.Further,marital opportunities can be fewer among stunted individuals[3].Hence,all measures to achieve adequate growth should be attempted in children with CKD,regardless of whether they undergo transplantation.

Diagnosis,treatment protocols,and outcomes of liver transplant recipients infected with COVID-19

Several cases of fatal pneumonia during November 2019 were linked initially to severe acute respiratory syndrome coronavirus 2,which the World Health Organization later designated as coronavirus disease 2019(COVID-19).The World Health Organization declared COVID-19 as a pandemic on March 11,2020.In the general population,COVID-19 severity can range from asymptomatic/mild symptoms to seriously ill.Its mortality rate could be as high as 49%.The Centers for Disease Control and Prevention have acknowledged that people with specific underlying medical conditions,among those who need immunosuppression after solid organ transplantation(SOT),are at an increased risk of developing severe illness from COVID-19.Liver transplantation is the second most prevalent SOT globally.Due to their immunosuppressed state,liver transplant(LT)recipients are more susceptible to serious infections.Therefore,comorbidities and prolonged immunosuppression among SOT recipients enhance the likelihood of severe COVID-19.It is crucial to comprehend the clinical picture,immunosuppressive management,prognosis,and prophylaxis of COVID-19 infection because it may pose a danger to transplant recipients.This review described the clinical and laboratory findings of COVID-19 in LT recipients and the risk factors for severe disease in this population group.In the following sections,we discussed current COVID-19 therapy choices,reviewed standard practice in modifying immunosuppressant regimens,and outlined the safety and efficacy of currently licensed drugs for inpatient and outpatient management.Additionally,we explored the clinical outcomes of COVID-19 in LT recipients and mentioned the efficacy and safety of vaccination use.

Cryptococcosis in kidney transplant recipients:Current understanding and practices

Cryptococcosis is the third most commonly occurring invasive fungal disease in solid organ transplant recipients(SOT).It is caused by encapsulated yeast,Cryptococcus species,predominantly Cryptococcus neoformans and Cryptococcus gattii.Though kidney transplant recipients are at the lowest risk of cryptococcosis when compared to other solid organ transplant recipients such as lung,liver or heart,still this opportunistic infection causes significant morbidity and mortality in this subset of patients.Mortality rates with cryptococcosis range from 10%-25%,while it can be as high as 50%in SOT recipients with central nervous system involvement.The main aim of diagnosis is to find out if there is any involvement of the central nervous system in disseminated disease or whether there is only localized pulmonary involvement as it has implications for both prognostication and treatment.Detection of cryptococcal antigen(CrAg)in cerebrospinal fluid or plasma is a highly recommended test as it is more sensitive and specific than India ink and fungal cultures.The CrAg lateral flow assay is the single point of care test that can rapidly detect cryptococcal polysaccharide capsule.Treatment of cryptococcosis is challenging in kidney transplant recipients.Apart from the reduction or optimization of immunosuppression,lipid formulations of amphotericin B are preferred as induction antifungal agents.Consolidation and maintenance are done with fluconazole;carefully monitoring its interactions with calcineurin inhibitors.This review further discusses in depth the evolving developments in the epidemiology,pathogenesis,diagnostic assays,and management approach of cryptococcosis in kidney transplant recipients.

Risk stratification of renal transplant recipients using routine parameters: Implication of learning from SARS-CoV-2 into transplant follow-up program

BACKGROUND Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)infection is a global pandemic that is associated with a high risk of morbidity and mortality among recipients of solid organ transplantation.In the course of acute SARS-CoV-2 infection,various laboratory markers have been identified as predictors for high risk of mortality.AIM To risk stratify renal transplant recipients(RTxR)using general demographic parameters,comorbidities and routine laboratory markers for the severity of the disease and its outcomes.We believe that learning about these routinely monitored parameters can help us plan better strategies for the RTxR follow-up program.METHODS This present study includes RTxR who acquired SARS-CoV-2 infection from March 2020 to February 2021.We recorded the basic demographics,comorbidities and routine laboratory markers.We investigated the impact of SARS-CoV-2 infection on RTxRs and risk-stratified the progression of disease severity and outcomes in terms of recovery or mortality.RESULTS From 505 RTxRs in our renal transplant follow-up program,29(7.75%)RTxRs had PCR-positive SARS-CoV-2 infection.We recorded 8 deaths from SARS-CoV-2 infection giving an overall mortality rate of 1.6%but a significant 27.6%mortality in SARS-CoV-2 positive recipients.Age more than 68 years,non-Caucasian ethnicity and male gender were associated with a significant drop in survival probability;P≤0.001.<0.001 and<0.0001 respectively.87.5%of the deceased were diabetic;P≤0.0.0001.Estimated glomerular filtration rate of less than 26 mL/min/1.73 m2,serum albumin less than 20 g/L,Hemoglobin less than 9.6 g/L and serum calcium less than 1.70 mmol/L were all associated with significantly increased risk of mortality;P=0.0128,<0.001,<0.0001 and 0.0061 respectively.CONCLUSION This study has identified some routinely used modifiable parameters in predicting a higher risk of mortality and morbidity.This knowledge can be used in RTxR follow-up programs by addressing these parameters early to help reduce the morbidity and mortality in RTxRs.

Different behaviour of BK-virus infection in liver transplantrecipients

Polyomavirus BK(BKV) infects up to 90% of the general population. After primary infection, occurring early during childhood, a state of non-replicative infection is established in the reno-urinary tract, without complications for immunocompetent hosts. In immunocompromised individuals, particularly transplanted patients, asymptomatic BKV viremia and/or viruria can be observed. Renal grafts may also be sources of infection as BKV prefers kidneys rather than other solid organs for transplantation such as the liver. The mechanism behind the higher incidence of BKV infection in kidney transplant patients, compared to liver or heart transplantation, is unclear and the prevalence of BKV infection in non-renal solid organ transplants has not been yet thoroughly investigated. We evaluated the prevalence of Polyomavirus BK infection among liver transplant recipients. A Pub Med search was conducted using the terms BKV infection AND liver transplant recipients; BKV AND non-renal solid organ transplant*; BKV infection AND immunosuppression; the search was limited to title/abstract and English-language articles published from 2000, to March 2015. Eleven relevant studies suggest that the prevalence of BKV viruria and/or viremia among liver transplant recipients is less than that reported in kidney or heart transplant recipients, except when chronic kidney disease(CKD) is present at the same time. Data also suggest that viruric and viremic patients have higher levels of serum creatinine than BKV negative patients. Moreover, no specific immunosuppressive drugs are associated with the onset of BKV nephropathy. The comorbidity of transplantation and CKD could play a major role in promoting BKV replication.

Renal function and physical fitness after 12-mo supervised training in kidney transplant recipients

AIM To evaluate the effect of a 12-mo supervised aerobic and resistance training, on renal function and exercise capacity compared to usual care recommendations.METHODS Ninety-nine kidney transplant recipients(KTRs) were assigned to interventional exercise(Group A; n = 52) and a usual care cohort(Group B; n = 47). Blood and urine chemistry, exercise capacity, muscular strength, anthropometric measures and health-related quality of life(HRQo L) were assessed at baseline, and after 6 and 12 mo. Group A underwent a supervised training three times per week for 12 mo. Group B received only general recommendations about home-based physical activities.RESULTS Eighty-five KTRs completed the study(Group A, n = 44; Group B, n = 41). After 12 mo, renal function remained stable in both groups. Group A significantly increased maximum workload(+13 W, P = 0.0003), V'O2 peak(+3.1 mL/kg per minute, P = 0.0099), muscular strength in plantar flexor(+12 kg, P = 0.0368), height in the countermovement jump(+1.9 cm, P = 0.0293) and decreased in Body Mass Index(-0.5 kg/m^2, P = 0.0013). HRQo L significantly improved in physical function(P = 0.0019), physical-role limitations(P = 0.0321) and social functioning scales(P = 0.0346). Noimprovements were found in Group B.CONCLUSION Twelve-month of supervised aerobic and resistance training improves the physiological variables related to physical fitness and cardiovascular risks without consequences on renal function. Recommendations alone are not sufficient to induce changes in exercise capacity of KTRs. Our study is an example of collaborative working between transplant centres, sports medicine and exercise facilities.

Role of steroid maintenance in sensitized kidney transplant recipients

AIM: To evaluate whether there is a threshold sensitization level beyond which benefits of chronic steroid maintenance(CSM) emerge. METHODS: Using Organ Procurement and Transplant Network/United Network of Organ Sharing database, we compared the adjusted graft and patient survivals for CSM vs early steroid withdrawal(ESW) among patients who underwent deceased-donor kidney(DDK) transplantation from 2000 to 2008 who were stratified by peak-panel reactive antibody(peak-PRA) titers(0%-30%, 31%-60% and > 60%). All patients received perioperative induction therapy and maintenance immunosuppression based on calcineurin inhibitor(CNI) and mycophenolate mofetil(MMF).RESULTS: The study included 42851 patients. In the 0%-30% peak-PRA class, adjusted over-all graft-failure(HR 1.11, 95%CI: 1.03-1.20, P = 0.009) and patientdeath(HR 1.29, 95%CI: 1.16-1.43, P < 0.001) risks were higher and death-censored graft-failure risk(HR 1.06, 95%CI: 0.98-1.14, P = 0.16) similar for CSM(n = 25218) vs ESW(n = 7399). Over-all(HR 1.04, 95%CI: 0.85-1.28, P = 0.70) and death-censored(HR 0.97, 95%CI: 0.78-1.21, P = 0.81) graft-failure risks were similar and patient-death risk(HR 1.39, 95%CI: 1.03-1.87, P = 0.03) higher for CSM(n = 3495) vs ESW(n = 850) groups for 31%-60% peak-PRA class. In the > 60% peak-PRA class, adjusted overall graft-failure(HR 0.90, 95%CI: 0.76-1.08, P = 0.25) and patientdeath(HR 0.92, 95%CI: 0.71-1.17, P = 0.47) risks were similar and death-censored graft-failure risk lower(HR 0.84, 95%CI: 0.71-0.99, P = 0.04) for CSM(n = 4966)vs ESW(n = 923).CONCLUSION: In DDK transplant recipients who underwent perioperative induction and CNI/MMF maintenance, CSM appears to be associated with increased risk for death with functioning graft in minimally-sensitized patients and improved death-censored graft survival in highly-sensitized patients.

Depressive symptoms and associated factors among renal-transplant recipients in China

Aim:This study aimed to explore depressive symptoms and associated factors among renal-transplant(RT)recipients in China.Methods:This study included 287 RT recipients.Data were collected from August to November 2014 by utilizing demographic forms,namely,the Self-rating Depression Scale and the Multidimensional Scale of Perceived Social Support.Descriptive statistics,Student's t test,Chi-square test,ANOVA,and multiple linear regression were used for data analysis.Results:More than half of the recipients presented depressive symptoms.All recipients in the four transplant period groups(≤5 yr,5e10 yr,10e15 yr,and>15 yr)reported greater depressive symptoms than the Norm.No significant difference was observed in the depressive symptoms in the four transplant period groups.Multiple linear regression indicated that depressive symptoms were significantly associated with employment status,economic burden,inhabitation area,and social support.Conclusion:Depression is common among RT recipients in China.Employment status,economic burden,inhabitation area,and social support are the main factors affecting depression among RT recipients.Follow-up clinics should prescribe the evaluation of depression as a routine examination for RT patients.Moreover,depressed recipients must be provided with individualized care by collecting information on the depressive symptoms,employment status,economic burden,inhabitation area,and perceived social support of recipients.

Kidney transplantation in older recipients:Preemptive high KDPI kidney vs lower KDPI kidney after varying dialysis vintage

AIM To evaluate the outcomes of transplanting marginal kidneys preemptively compared to better-quality kidneys after varying dialysis vintage in older recipients.METHODS Using OPTN/United Network for Organ Sharing database from 2001-2015, we identified deceased donor kidney(DDK) transplant recipients > 60 years of age who either underwent preemptive transplantation of kidneys with kidney donor profile index(KDPI) ≥ 85%(marginal kidneys) or received kidneys with KDPI of 35%-84%(better quality kidneys that older wait-listed patients would likely receive if waited longer) after being on dialysis for either 1-4 or 4-8 years. Using a multivariate Cox model adjusting for donor, recipient and transplant related factors-overall and death-censored graft failure risks along with patient death risk of preemptive transplant recipients were compared to transplant recipients in the 1-4 and 4-8 year dialysis vintage groups.RESUTLS The median follow up for the whole group was 37 mo(interquartile range of 57 mo). A total of 6110 DDK transplant recipients above the age of 60 years identified during the study period were found to be eligible to be included in the analysis. Among these patients350 received preemptive transplantation of kidneys with KDPI ≥ 85. The remaining patients underwent transplantation of better quality kidneys with KDPI 35-84% after being on maintenance dialysis for either 1-4 years(n = 3300) or 4-8 years(n = 2460). Adjusted overall graft failure risk and death-censored graft failure risk in preemptive high KDPI kidney recipients were similar when compared to group that received lower KDPI kidney after being on maintenance dialysis for either 1-4 years(HR 1.01, 95%CI: 0.90-1.14, P = 0.84 and HR 0.96, 95%CI: 0.79-1.16, P = 0.66 respectively) or 4-8 years(HR 0.82, 95%CI: 0.63-1.07, P = 0.15 and HR 0.81, 95%CI: 0.52-1.25, P = 0.33 respectively). Adjusted patient death risk in preemptive high KDPI kidney recipients were similar when compared to groups that received lower KDPI kidney after being on maintenance dialysis for 1-4 years(HR 0.99, 95%CI: 0.87-1.12, P = 0.89) but lower compared to patients who were on dialysis for 4-8 years(HR 0.74, 95%CI: 0.56-0.98, P = 0.037).CONCLUSION In summary, our study supports accepting a "marginal" quality high KDPI kidney preemptively in older waitlisted patients thus avoiding dialysis exposure.

Use of Muscle Feeding Arteries as Recipient Vessels for Soft Tissue Reconstruction in Lower Extremities

Summary:Microsurgical free tissue transfer is still playing an important role in lower extremity reconstruction.Finding a suitable recipient artery for anastomosis is critical in the microsurgical procedure,especially in an extensive wound,or in a complex trauma combined with vascular injury.From April 2014 to March 2018,we retrospectively reviewed patients with traumatic/posttraumatic,oncologic,and electrical wounds in the lower extremity.Those treated with muscle feeding artery as recipient vessels were included.The latissimus dorsi(LD)muscle free flap,anterior lateral thigh(ALT)perforator free flap,and deep inferior epigastric perforator(DIEP)free flap were raised.The muscle feeding arteries to vastus lateral muscle and to medial head of gastrocnemius muscle,concomitant veins,and great saphenous vein were used as recipient vessels.Injuries included in the study were caused by tumour in 2 cases,car accident in 3 cases,crushing in 3 cases,burns in one case,and electrical injury in one case.The wound size varied from 14 cm x 6 cm to 30 cm x 20 cm.LD,ALT,and DIEP free flaps were used in 6,3,and 4 patients,respectively.The muscle feeding arteries to medial head of gastrocnemius muscle,to sartorius muscle,and to vastus lateral muscle were used as recipient arteries in 4,5,and one patient,respectively.Concomitant and great saphenous veins were used as recipient veins in 10 and 4 patients,respectively.Using the muscle feeding artery is feasible to avoid injury to the main artery and facilitate dissection and anastomoses,particularly when the wound is located proximal to the mid-third of the lower leg.

Efficient and Provably Secure Multi-Recipient Signcryption from Bilinear Pairings

Signcryption is a cryptographic primitive that performs signature and encryption simultaneously, at lower computational costs and communication overheads than the signature-then- encryption approach. In this paper, we propose an efficient multi-recipient signcryption scheme based on the bilinear pairings, which broadcasts a message to multiple users in a secure and authenticated manner. We prove its semantic security and unforgeability under the Gap Diffie-Hellman problem assumption in the random oracle model. The proposed scheme is more efficient than re-signcrypting a message n times using a signcryption scheme in terms of computational costs and communication overheads.

Clinical outcomes of coronavirus disease 2019 in liver transplant recipients

BACKGROUND Liver transplant patients are at higher risk of infection due to immunosuppression.Whether liver transplant recipients are also more susceptible to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and will have worse outcomes than the general population if they develop coronavirus disease 2019(COVID-19)due to SARS-CoV-2 is a topic of ongoing studies,including ours.AIM To assess the clinical outcomes of COVID-19 in liver transplant recipients.METHODS This was a case-control study,with a database search performed(at the study site)from March 1,2020 through February 28,2021.Patients 18 years or older who tested positive for SARS-CoV-2 via polymerase chain reaction(PCR)were included in the study.Patients with infection other than pneumonia at the time of admission were excluded.After selection,patients who had been the recipient of liver transplant were considered cases and those without as controls.After being matched by age,sex,and obesity,two controls were randomly selected for each case.Death and hospitalization due to COVID-19 infection were the primary outcomes.Secondary outcomes were pertinent only to patients who were hospitalized,and they included duration of hospital stay,need for supplemental oxygen,presence of at least one type of end-organ damage,effects on liver enzymes,incidence of acute liver failure,effect on d-dimer levels,and incidence of venous thromboembolism(VTE).Chi-square or Fisher’s exact test was used to compare all primary and secondary outcomes with the exception of duration of hospital stay and d-dimer levels,which were compared using the Wilcoxon signed-rank test.Alpha criterion was set at 0.05.Logistic regression was performed for each primary outcome(as the dependent variable).Statistical analyses were performed using R software.RESULTS Of the 470 Liver transplant recipients who were tested for COVID-19 via the PCR test,39 patients tested positive(8.3%).There was no significant difference between cases and controls regarding death[odds ratio(OR):2.04,95%confidence interval(CI):0.14–29.17;P=0.60]and hospitalization rates(OR:1.38,95%CI:0.59–3.24;P=0.46).There also was no significant difference between cases and controls with respect to all secondary outcomes.Among all patients who had elevated liver enzymes,their levels were either normalized,improving,or remained stable at the time of discharge.No patient developed acute liver failure.Of the 31 hospitalized patients,27 received a prophylactic anticoagulation dose and no patient developed VTE in either group.Among cases who were hospitalized,immunosuppression was decreased in 5 patients and there was no change in immunosuppression among the remaining 7 patients.One patient died in each of these two subgroups.Logistic regression analysis was done,but all of the models had poor model predictions as well as insignificant predictors(independent variables).Therefore,they could not be used for either prediction or inference.CONCLUSION Clinical outcomes of COVID-19 in liver transplant recipients are not different than those without transplantation.COVID-19 should not impact timely health care access and immunosuppression continuation among these patients.

Graft-to-recipient weight ratio lower to 0.7% is safe without portal pressure modulation in right-lobe living donor liver transplantation with favorable conditions

BACKGROUND: The low graft-to-recipient weight ratio(GRWR) in adult-to-adult living donor liver transplantation(LDLT) is one of the major risk factors affecting graft survival. The goal of this study was to evaluate whether the lower limit of the GRWR can be safely reduced without portal pressure modulation in right-lobe LDLT. METHODS: From 2005 to 2011, 317 consecutive patients from a single institute underwent LDLT with right-lobe grafts without portal pressure modulation. Of these, 23 had a GRWR of less than 0.7%(group A), 27 had a GRWR of ≥0.7%, 【0.8%(group B), and 267 had a GRWR of more than and equal to 0.8%(group C). Medical records, including recipient, donor, operation factors, laboratory findings and complications were reviewed retrospectively. RESULTS: The baseline demographics showed low model for end-stage liver disease score(mean 16.3±8.9) and high percentage of hepatocellular carcinoma(231 patients, 72.9%). Three groups by GRWR demonstrated similar characteristics except recipient body mass index and donor gender. For smallforsize syndrome, there were 3(13.0%) in group A, 1(3.7%) in group B, and 2 patients(0.7%) in group C(P【0.001). Hepatic artery thrombosis was more frequently observed in group A than in groups B and C(8.7% vs 3.7% vs 1.9%, P=0.047). However, among the three groups, graft survival rates at 1 year(100% vs 96.3% vs 93.6%) and 3 years(91.7% vs 73.2% vs 88.1%) were not different(P=0.539). In laboratory measurements,there was no group difference in total bilirubin and albumin. However, prothrombin time was longer in group A within postoperative 1 week and platelet count was lower in groups A and B within postoperative 1 month. CONCLUSION: A GRWR lower to 0.7% is safe and does not need to modulate portal pressure in adult-to-adult LDLT using the right-lobe in favorable conditions including low model for end-stage liver disease score.

Metabolic and functional effects of exercise training in diabetic kidney transplant recipients

BACKGROUND Physical activity levels are significantly lower in kidney transplant(KT)recipients compared to the general population.The effects of exercise training in KT recipients with diabetes mellitus remain unclear,and so little is known about the role of increased exercise on cardiovascular risk and metabolic profile of KT patients.AIM To investigate the effects of a 6-mo home-based exercise training program on functional capacity,glucose levels and lipid profile of diabetic KT patients.METHODS In total,21 type II diabetic KT recipients were randomly assigned into two groups:Exercise(n=11,aged 52.9±10.1 years)and control(n=10,aged 53.01±9.5 years).All participants at baseline and the end of the study underwent biochemical tests for fasting plasma glucose levels,glycated hemoglobin and lipid profile and cardiopulmonary exercise testing for maximum oxygen uptake[(VO2)peak]estimation.The exercise group followed a 6-mo supervised home-based aerobic and progressive resistance exercise program of moderate intensity 3 times per week,while the control group continued to receive usual care.RESULTS At the end of the 6-mo study,the exercise group had significantly lower values in fasting plasma glucose by 13.4%(from 120.6±28.9 mg/dL to 104.8±21.9 mg/dL,P=0.01),glycated hemoglobin by 1.5%(from 6.7%±0.4 to 6.6%±0.4,P=0.01)and triglycerides by 8.5%(from 164.7±14.8 mg/dL to 150.8±11.6 mg/dL,P<0.05)and higher values in high-density lipoprotein by 10.2%(from 51.4±8.8 mg/dL to 57.2±8.7 mg/dL,P<0.05)and(VO_(2))_(peak)by 4.7%(from 22.7±3.3 to 23.8±4.2,P=0.02)than the control group.There were statistically significant differences between the two groups at the end of the study for fasting plasma glucose(decreased by 9.6%,P<0.05),triglycerides(decreased by 4.5%,P=0.04)and(VO_(2))_(peak)(increased by 4.4%,P=0.01).Finally,after training,there was a moderate,positive linear relationship between(VO_(2))_(peak)and glycated hemoglobin in the exercise group(r=0.408,P=0.03).CONCLUSION The results demonstrated that a 6-mo home-based mixed type exercise training program can improve the functional capacity,levels of glucose and lipid profile of diabetic KT recipients.

Matching donor to recipient in liver transplantation: Relevance in clinical practice

Achieving optimum outcomes after liver transplantation requires an understanding of the interaction between donor,graft and recipient factors.Within the cohort of patients waiting for a transplant,better matching of the donor organ to the recipient will improve transplant outcomes and benefit the overall waiting list by minimizing graft failure and need for re-transplantation.A PubMed search was conducted to identify published literature investigating the effects of donor factors such as age,gender,ethnicity,viral serology;graft factors such as size and quality,recipient factors such as age,size,gender and transplant factors such as major or minor blood group incompatibility and immunological factors.We also report technical and therapeutic modifications that can be used to manage donor-recipient mismatch identified from literature and the authors’clinical experience.Multiple donor and recipient factors impact graft survival after liver transplantation.Appropriate matching based on donor-organ-recipient variables,modification of surgical technique and innovative peri-transplant strategies can increase the donor pool by utilizing grafts from marginal donors that are traditionally turned down.

Evaluating twenty-years of follow-up after orthotopic liver transplantation, best practice for donor-recipient matching: What can we learn from the past era?

AIM To characterize major determinants of 20-year survival after liver transplantation(LT).METHODS This longitudinal single-institution study includes 313 consecutive patients who received a LT between 1988 and 1992. Pretransplant clinical characteristics and laboratory values were assessed and compared between 20-year survivors and non-survivors. Particular attention was paid to the Model for End-Stage Liver Disease(labM ELD)-score and the Eurotransplant Donor Risk Index(ET-DRI) to unravel their impact on 20-year survival after LT.RESULTS Twenty-year survivors were significantly younger(44 vs 50 years, P = 0.001), more likely to be female(49% vs 36%, P = 0.03) and less likely to be obese at the time of LT(19% vs 32%, P = 0.011). Mean labM ELD-score(P = 0.156), rate of high-urgency LT(P = 0.210), coldischemia time(P = 0.994), rate of retransplantation(P = 0.12) and average donor age(28 vs 33 years, P = 0.099) were not statistically different. The mean estimated glomerular filtration rate was higher among survivors(P = 0.007). ET-DRI > 1.4(P = 0.020) and donor age ≥ 30 years(P < 0.022) had significant influence on 20-year survival. The overall survival was not significantly impacted by labM ELD-score categories(P = 0.263).CONCLUSION LT offers excellent long-term results in case of optimal donor and recipient conditions. However, mainly due to the current organ shortage, these ideal circumstances are rarely given; thus algorithms for donor-recipient matching need to be refined, in order to enable a maximum benefit for the recipients of high quality as well as marginal organs.

Recipients of 2016 AJCC Most Influential Paper Award

The editorial board of American Journal of Climate Change (AJCC) announces Recipients of 2016 AJCC Influential Paper Award.