The Key Role of Warm and Cold Ischemia in Uterus Transplantation: A Review

Midlateral Approach Replantation of a Distal Phalanx Second Toe Amputation in a 4-Year-Old Child: A Case Report

CASE

A 4-year-old girl patient presented with complete amputation of the second toe close to the distal interphalangeal joint. Replantation was performed using a novel midlateral approach. The procedure used the dorsal subcutaneous vein on the foot as a graft for the artery. Four months postoperatively, the toe healed without any complication. The patient reported pain-free physical exercise without limitations in daily activity.

CONCLUSION

This report demonstrates that this approach has the potential to provide a safe and viable alternative for treating toe amputations and offers advantages such as simplified artery identification, straightforward anastomosis, and improved vein graft harvesting.

Hypothermic machine perfusion for uterus transplantation

OBJECTIVE

To describe the feasibility of hypothermic machine perfusion (HMP) in uterus transplantation (UT) to potentially improve the preservation of the uterus and enhance graft preservation in the donation after brainstem death (DBD) context. Uterus transplantation is a new surgical approach to treating absolute uterine infertility; it can be performed after living donation or after DBD. In the DBD context, the uterus is typically the last organ removed after other vital organs, with the exception of the Baylor team, which removes the uterus first. This key aspect imposes an unavoidable mild temperature ischemia for >1 hour on the uterus during the removal of the vital abdominal and chest organs. In renal transplantation, the perfusion machine reduces the risk of delayed graft function; thus, we hypothesized that machine perfusion could result in a reduction of uterus graft dysfunction. The uterus graft dysfunction could be expressed by a low embryo implantation rate, pregnancy loss, or vascular pregnancy diseases such as preeclampsia or fetal growth restriction." To date, static cold storage of the uterus is the only standard method for preservation before transplantation. HMP is an emerging method that could potentially improve the preservation of the uterus to enhance graft preservation in the DBD context.

DESIGN

This video article shows all the technical details of using the HMP for uterine transplantation.

SETTING

University.

ANIMALS

Porcine model.

INTERVENTION

Porcine uterus was retrieved from a DBD domestic animal model and flushed with KPS MP (Bridge To Life Ltd in UK) at 4 °C. After vascular preparation on the back table, the uterus was perfused using KPS MP through a cannula in the aorta using the VitaSmart device (Bridge To Life Ltd in UK) for 18 hours. Then, the uterus was transplanted to the porcine recipient.

MAIN OUTCOME MEASURES

The macroscopic appearance of the uterus at the end of HMP and the assessment of the uterus vascularization after transplantation in the recipient compared with the native uterus.

RESULTS

This video shows the cannulation of the iliac vessels, cooling and removal of the uterus on a porcine model, uterus preservation using HMP during 18 hours, and then UT in a new recipient pig with the reperfusion of the transplanted uterus next to the native, intact uterus of the recipient. The macroscopic appearance of the uterus at the end of HMP appeared viable and was perfectly flushed. The assessment of the uterus vascularization after transplantation in the recipient was similar to that of the native uterus. To our knowledge, we describe here for the first time the UT procedure in DBD context on an animal model and the use of HMP for uterus preservation in UT programs; this could increase the number of uterine grafts available for a greater number of female recipients.

CONCLUSION

Hypothermic machine perfusion could allow the duration of cold ischemia to be prolonged without altering the uterine graft. Nevertheless, this assertion has to be validated in a human context.

Differences between living and deceased donation in human uterus transplantation: A narrative review

The decision to use a living or deceased donor to perform uterus transplantation (UTx) is an evaluation of benefit and harm and is based on the medical team's choices. The current study determines the differences between living and deceased donation in human UTx according to determinant factors in choosing the donor type. For this review study, the PubMed database was searched without time, language, and location limitations up to May 2022. From 113 identified articles, 45 papers were included in the study for review. According to the results, in comparison to living donation, the biggest advantage of deceased donation is the lack of surgical and or psychological risks for the donor. In contrast, a comprehensive pre-transplantation medical assessment is less possible in deceased donation, and preplanned surgery cannot be realized. According to published peer-reviewed clinical trials on UTx, the graft failure rates in living and deceased donor UTx are 21% and 36%, respectively. Supposing all recipients who did not have graft failure underwent embryo transfer, live birth rates in living and deceased donor UTx procedures are almost 63% and 71%, respectively. Currently, considering the occurrence of live births from both donations, particularly from nulliparous deceased donor, increased demand for UTx in the near future, shortage of uterus grafts, and lack of sufficient data for a comprehensive comparison between the 2 types of donation, the use of both donations still seems necessary and rational.

Uterus Transplantation: Revisiting the Question of Deceased Donors versus Living Donors for Organ Procurement

Uterus transplantation is a surgical treatment for women with congenital or acquired uterine factor infertility. While uterus transplantation is a life-enhancing transplant that is commonly categorized as a vascular composite allograft (e.g., face or hand), it is similar to many solid organ transplants (e.g., kidney) in that both living donors (LDs) and deceased donors (DDs) can be utilized for organ procurement. While many endpoints appear to be similar for LD and DD transplants (including graft survival, time to menses, livebirth rates), there are key medical, technical, ethical, and logistical differences between these modalities. Primary considerations in favor of a LD model include thorough screening of donors, enhanced logistics, and greater donor availability. The primary consideration in favor of a DD model is the lack of physical or psychological harm to a living donor. Other important factors, that may not clearly favor one approach over the other, are important to include in discussions of LD vs. DD models. We favor a stepwise approach to uterus transplantation, one in which programs first begin with DD procurement before attempting LD procurement to maximize successful organ recovery and to minimize potential harms to a living donor.

Technological Advancements in Uterus Transplantation

Uterus transplantation is barely a decade old and in a young, evolving field it is hard to identify "technological advances" since it is, in of itself, a technological advance. Nonetheless, one can still identify advances in diagnostic imaging that have improved donor screening to avoid graft losses, highlight the adoption of robotic surgery to make the living donor uterus procurement more minimally invasive, and look to a future of biotechnology like perfusion pumps and bioengineering such as synthetic uterus to increase donor supply. Additional technologies are on the horizon and promise to shape the field further.

Trimetazidine an emerging paradigm in renal therapeutics: Preclinical and clinical insights

Trimetazidine (TMZ) is a well-known anti-ischemic agent used for the treatment of angina pectoris. In the past decades, the efficacy of this drug has been tested in a wide range of kidney injuries, including drug-induced nephrotoxicity (DIN), radio-contrast agent-induced nephropathy, and surgically induced renal ischemic injury. TMZhas renoprotective effects by attenuating oxidative stress, inflammatory cytokine release, maintaining oxygen and energy balance. Moreover, TMZ administration prevented kidney graft rejection in the porcine model by suppressing the infiltration of mononuclear cells, preserving mitochondrial functions, and maintaining Ca+ homeostasis. In DIN and diabetic kidney diseases,TMZ treatment prevents renal injury by inactivating immune cells, attenuating renal fibrosis, inflammation, apoptosis, and histological abnormalities. Interestingly, the clinical therapeutic efficacy of TMZ has also been documented in pre-existing kidney disease patients undergoing contrast exposure for diagnostic intervention. However, the mechanistic insights into the TMZ mediated renoprotective effects in other forms of renal injuries, including type-2 diabetes, drug-induced nephrotoxicity, and hypertension-induced chronic kidney diseases, remain uninvestigated and incomplete. Moreover, the clinical utility of TMZ as a renoprotective agent in radio-contrast-induced nephrotoxicity needs to be tested in a large patient population. Nevertheless, the available pieces of evidence suggest that TMZ is a promising and emerging renal therapy for the treatment and management of kidney diseases of variable etiologies. This review discusses the various pre-clinical and clinical findings and provides mechanistic insights into the TMZ mediated beneficial effects in various kidney diseases.

Evolution and Transformation of Uterine Transplantation: A Systematic Review of Surgical Techniques and Outcomes

BACKGROUND

 Uterine transplantation (UTx) is acknowledged to be on the second (2A) of five steps of development in accordance with the staging system for the evaluation of surgical innovations. Accordingly, we aimed to systematically review the available evidence of the surgical techniques and outcomes of UTx in terms of graft survival.

METHODS

 A comprehensive search was conducted across PubMed Medline, Cochrane-EBMR, Scopus, Web of Science, and CENTRAL through November 2020.

RESULTS

 Forty studies, reporting 64 recipients and 64 donors, satisfied inclusion criteria. The surgical time and the estimated blood loss were 515 minutes and 679 mL for graft procurement via laparotomy, 210 minutes and 100 mL for laparoscopic-assisted graft harvest, and 660 minutes and 173 mL for robotic-assisted procedures, respectively. Urinary tract infections (n = 8) and injury to the urinary system (n = 6) were the most common donor complications. Using the donor's internal iliac system, two arterial anastomoses were performed in all cases. Venous outflow was accomplished through the uterine veins (UVs) in 13 cases, a combination of the UVs and the ovarian/uteroovarian veins (OVs/UOVs) in 36 cases, and solely through the OVs/UOVs in 13 cases. Ischemia time was 161 and 258 minutes when using living donors (LD) and deceased donors (DD), respectively. Forty-eight uteri were successfully transplanted or fulfilled the purpose of transplantation, 41 from LDs and 7 from DDs. Twenty-five and four live childbirths from LDs and DDs have been reported, respectively.

CONCLUSION

 UTx is still experimental. Further series are required to recommend specific surgical techniques that best yield a successful transplant and reduce complications for donors and recipients.

Uterus transplantation: state of the art in 2021

PURPOSE

To provide a comprehensive review of uterus transplantation in 2021, including a discussion of pregnancy outcomes of all reported births to date, the donor and recipient selection process, the organ procurement and transplant surgeries, reported complications, postoperative monitoring, preimplantation preparation, and ethical considerations.

METHODS

Literature review and expert commentary.

RESULTS

Reports of thirty-one live births following uterus transplantation have been published from both living and deceased donors. The proper selection of donors and recipients is a labor-intensive process that requires advanced planning. A multidisciplinary team is critical. Reported complications in the recipient include thrombosis, infection, vaginal stricture, antenatal complications, and graft failure. Graft rejection is a common occurrence but rarely leads to graft removal. While most embryo transfers are successful, recurrent implantation failures in uterus transplant patients have been reported. Rates of preterm delivery are high but appear to be declining; more data, including long-term outcome data, is needed.

CONCLUSIONS

Uterus transplantation is an emerging therapy for absolute uterine factor infertility, a condition previously without direct treatment options. It is paramount that reproductive health care providers are familiar with the uterus transplantation process as more patients seek and receive this treatment.

Mitochondria and Antibiotics: For Good or for Evil?

The discovery and application of antibiotics in the common clinical practice has undeniably been one of the major medical advances in our times. Their use meant a drastic drop in infectious diseases-related mortality and contributed to prolonging human life expectancy worldwide. Nevertheless, antibiotics are considered by many a double-edged sword. Their extensive use in the past few years has given rise to a global problem: antibiotic resistance. This factor and the increasing evidence that a wide range of antibiotics can damage mammalian mitochondria, have driven a significant sector of the medical and scientific communities to advise against the use of antibiotics for purposes other to treating severe infections. Notwithstanding, a notorious number of recent studies support the use of these drugs to treat very diverse conditions, ranging from cancer to neurodegenerative or mitochondrial diseases. In this context, there is great controversy on whether the risks associated to antibiotics outweigh their promising beneficial features. The aim of this review is to provide insight in the topic, purpose for which the most relevant findings regarding antibiotic therapies have been discussed.

Deceased Donation Uterus Transplantation: A Review

Uterus transplantation (UTx) offers women with absolute uterine factor infertility the option to gestate and birth their own biologically related child. The first birth following living donation UTx happened in 2014. The first birth following deceased donation happened in December 2017, with further successes since. Interest in deceased donation UTx is increasing. The authors established a database to track UTx clinical trials and outcomes. Utilising this database and existing literature, this article reviews the first reported cases of deceased donation UTx and outcomes, and drawing upon comparisons with living donor UTx, comments upon the future for this area of reproductive transplantation research. This is the first article to bring together the literature on deceased donation UTx procedures and outcomes.

Morphologic assessment of hypertonic citrate adenine, histidine-tryptophan-ketoglutarate, and university of Wisconsin solutions for hypothermic uterus preservation in rats

AIM

Optimizing perfusate for static cold storage is one of the key ways of reducing organ dysfunction and rejection in organ transplantation. Here, we tested the effectiveness of the three different solutions for hypothermic uterus preservation.

METHODS

Twenty rats were divided into four groups, five in each group. Uterine grafts were retrieved and perfused in situ. The uteri were preserved at 4°C in normal saline as control group (group NS), hypertonic citrate adenine (group HCA), histidine-tryptophan-ketoglutarate (group HTK), or university of Wisconsin solutions (group UW) for 0, 12, 24, and 48 h, respectively. HE, electron microscopy, TUNEL staining, and Cleaved Caspase3 immunohistochemical staining were assessed at each time point.

RESULTS

There was no significant difference in the uterine retrieval time, perfusion time, and the amount of perfusion solution in NS, HCA, HTK, and UW groups (p > 0.05). HCA and HTK can well preserve the pathological morphology of rat uterine tissues for up to 24 h, and the apoptosis rates of the two groups are 7.2% and 7.1%, respectively, with no statistical difference (p > 0.05). Still, the protective effect of HTK on the ultrastructure of cells was much better than HCA. There was a significant difference in the apoptosis rate of UW (6.5%), HTK (8.8%), and HCA (9.4%) at 48 h, with mitochondrial and endoplasmic reticulum structure well preserved only in UW.

CONCLUSION

At 4°C, normal saline is not suitable to preserve rat uterus for more than 12 h. The morphologic results would favor the use of HTK rather than HCA for short-term hypothermic uterus preservation (≤24 h). UW is better than HTK and HCA for 48 h hypothermic uterus preservation.

Custodiol-N Is Superior to Custodiol® Solution in Experimental Rat Uterus Preservation

Uterus transplantation (UTx) is the first and only available treatment for women with absolute uterine factor infertility. However, clinical application is limited by the lack of organs, ischemia/reperfusion injury, as well as immunosuppression after UTx. Several different preservation solutions are used in experimental and clinical UTx, including Custodiol^® solution. Recently, the novel Custodiol-N solution was developed with superior results in organ preservation. However, the solution was not tested yet in UTx. Therefore, the aims of this study were to evaluate the effect of Custodiol-N in uterus prolonged cold preservation time (8 and 24 h), compared to Custodiol^® solution. Uterus tissue samples were obtained from adult Sprague Dawley rats (n = 10/group). Cold ischemic injury was estimated by histology, including immunohistochemistry, and biochemical tissue analyses. After 8 h of cold ischemia, higher percentage of tissue edema, necrosis signs and myeloperoxidase expression, as well as lower superoxide dismutase activity were found in Custodiol^® compared to Custodiol-N (p < 0.05). These differences were more pronounced after 24 h of cold preservation time (p < 0.05). This study demonstrated that Custodiol-N protects uterus grafts from cold ischemic injury better than standard Custodiol^® most likely via inhibition of oxidative stress and tissue edema. It seems that iron chelators in the composition of Custodiol-N play an important protective role against cold ischemia.

Ethical Implications of Donor Type for Uterus Transplantation: Why We Should Remain Wary of Using Living Donors

Over the last few years, research teams have made significant advancements in treating absolute uterine factor infertility through uterus transplantation, culminating in the birth of the first US baby born from a uterus transplant in November 2017. However, studies have differed on the choice of either deceased or living donors, with some centers even exploring both methods. As researchers continue to investigate the medical feasibility of these approaches, it is also important for the medical community to consider how deceased and living uterus donation differ ethically. We argue that if living and deceased donation demonstrate equivalent clinical efficacy and the deceased donor pool is sufficient, living uterus donation should be reevaluated and may no longer be ethically justifiable.

Immunosuppression in uterine transplantation

Uterine transplantation (UTx) is the only effective treatment for uterine infertility patients to become genetic mothers. After decades of research, the surgical methods of UTx are very developed. There are numerous factors that affect the results of UTx, such as selection of the donor uterus before transplantation, immunosuppressive therapy post-transplantation, rejection monitoring, and immune tolerance. Studies have shown that immune rejection is a crucial factor affecting the survival rate after organ transplantation. Unlike liver or kidney transplantation, the aim of UTx is to obtain a functional uterus that is able to support successful pregnancy and birth of a healthy fetus. Because of the unique purpose of UTx, its immunosuppressive program is relatively specialized. Some immunosuppressive agents can cause perinatal complications, and inducing immune tolerance is necessary to resolve these side effects. Further understanding of the immune mechanism of UTx and the continuous development of new immunosuppressive agents, combined with the application of assisted reproductive technology, will be more conducive to the realization of UTx to breed offspring.