Innovations in reconstructive microsurgery: Reconstructive transplantation

What is needed to ensure long-term sustainability for the field of vascularized composite allotransplantation?

The field of vascularized composite allotransplantation (VCA) has demonstrated remarkable advances since its inception with some excellent long-term results in a variety of graft types. However, unlike solid organ transplantation, it has yet to become mainstream. We therefore discuss strategies on ensuring long-term sustainability by addressing continued clinical developments of VCA to improve the risk-to-benefit balance, importance of public support, improved policy and financial support, and need for a bridge to the future of transplant surgery. There has been headway on all fronts and collaboration among the VCA centers for centralization of data and incorporation of patient voices will be essential for continued progress.

Facial Nerve Revascularization Strategies in Facial Restoration

Facial transplants represent the current exemplar in the reconstruction of severely damaged faces, whereas conventional free flap reconstruction has its limitations in restoring both function and surface cover.

Addressing common orthopaedic calamities with microsurgical solutions

Reconstructive microsurgery has been an essential aspect of orthopaedic surgery and extremity reconstruction since the introduction of the operating microscope in the mid-20^th century. The reconstructive ladder ranges from simple healing by secondary intention to complex procedures such as free tissue transfer and vascularized composite allotransplantation. As orthopaedic surgery has evolved over the past 60 years, so too have the reconstructive microsurgical skills that are often needed to address common orthopaedic surgery problems. In this article, we will discuss a variety of complex orthopaedic surgery scenarios ranging from trauma to infection to tumor resection as well as the spectrum of microsurgical solutions that can aid in their management.

The current outcomes and future challenges in pediatric vascularized composite allotransplantation

PURPOSE OF REVIEW

We review the outcomes and future challenges associated with pediatric vascularized composite allotransplantation, including follow-up data from our bilateral pediatric hand-forearm transplantation.

RECENT FINDINGS

In 2015, the first heterologous pediatric upper extremity hand-forearm transplant was performed at the Children's Hospital of Philadelphia, and in 2019, the first pediatric neck reconstructive transplantation was performed in Poland. The 5-year follow-up of the pediatric upper extremity recipient demonstrates similar growth rates bilaterally, an increase in bone age parallel to chronologic age, and perhaps similar overall growth to nontransplant norms. The pediatric upper extremity recipient continues to make gains in functional independence. He excels academically and participates in various extracurricular activities. Future challenges unique to the pediatric population include ethical issues of informed consent, psychosocial implications, limited donor pool, posttransplant compliance issues, and greater life expectancy and therefore time to inherit the many complications of immunosuppression.

SUMMARY

Currently, we recommend pediatric vascularized composite allotransplantation (VCA) for bilateral upper extremity amputees, preferably on immunosuppression already, and those patients who would have the most potential gain not available through standard reconstructive techniques while being able to comply with postoperative immunosuppression protocols, surveillance, rehabilitation, and follow-up.

Blood proteome profiling using aptamer-based technology for rejection biomarker discovery in transplantation

Face transplantation is a promising solution for patients with devastating facial injuries who lack other satisfactory treatment options. At the same time, this type of transplantation is accompanied with high risks of acute transplant rejection. The limitations of traditional skin biopsy and the need to frequently monitor the condition of face transplant call for less invasive biomarkers to better diagnose and treat acute rejection. Discovery of peripheral serum proteins accurately reflecting the transplant status would represent a reasonable solution to meet this demand. However, to date, there is no clinical data available to address the feasibility of this approach. In this study, we used the next generation aptamer-based SOMAscan proteomics platform to profile 1305 proteins of peripheral blood serum in twenty-four samples taken from 6 patients during no-rejection, nonsevere rejection, and severe rejection episodes. Also, we provide a detailed description of biosample processing and all steps to generate and analyze the SOMAscan dataset with hope it will assist in performing biomarker discovery in other transplantation centers using this platform.

MMP3 Is a Non-invasive Biomarker of Rejection in Skin-Bearing Vascularized Composite Allotransplantation: A Multicenter Validation Study

Background: There is unmet need for non-invasive immunomonitoring to improve diagnosis and treatment of acute rejection in vascularized composite allotransplantation (VCA). Circulating matrix metalloproteinase 3 (MMP3) was described as a candidate non-invasive biomarker to predict treatment response to acute rejection in clinical VCA. However, larger validation studies are yet to be reported to allow for more definitive conclusions.

Methods: We retrospectively measured MMP3 levels using ELISA in a total of 140 longitudinal serum samples from six internal and three external face transplant recipients, as well as three internal and seven external upper extremity transplant recipients. The control groups comprised serum samples from 36 kidney transplant recipients, 14 healthy controls, and 38 patients with autoimmune skin disease. A linear mixed model was used to study the effect of rejection state (pre-transplant, no-rejection, non-severe rejection (NSR), and severe rejection) on MMP3 levels.

Results: In VCA, MMP3 levels increased significantly (p < 0.001) between pre- and post-transplant no-rejection states. A further increase occurred during severe rejection (p < 0.001), while there was no difference in MMP3 levels between non-severe and no-rejection episodes. A threshold of 5-fold increase from pre-transplant levels could discriminate severe from NSR with 76% sensitivity and 81% specificity (AUC = 0.79, 95% CI = 0.65–0.92, p < 0.001). In kidney transplantation, the MMP3 levels were significantly (p < 0.001) elevated during antibody-mediated rejection but not during T-cell mediated rejection (TCMR) (p = 0.547). MMP3 levels in healthy controls and autoimmune skin disease patients were comparable with either pre-transplant or no-rejection/NSR episodes of VCA patients.

Conclusion: The results of this study suggest that serum MMP3 protein is a promising marker for stratifying patients according to severity of rejection, complementary to biopsy findings.

A Call to Accountability: Reporting Outcomes in Vascularized Composite Allotransplantation

Because nearly all the vascularized composite allotransplants performed in the United States have been proposed and carried out as research, the ethical duty to report outcomes pertains. This duty is set forth in several international statements, including the World Health Organization’s Statement on Public Disclosure of Clinical Trial Results, the 2013 Helsinki Declaration, and the Singapore Statement on Research Integrity. These international statements call for the reporting of negative and inconclusive outcomes as well as positive outcomes, and for the reporting of results from previously unreported past research. In 2014, the Organ Procurement and Transplant Network vascularized composite allotransplant committee proposed mandatory data collection and submission requirements for transplants, but only for those which took place in September 2015 or later. Reporting of data for the allotransplants which took place before September 2015 was regarded as optional, even though the pre-September 2015 transplants represent the majority of vascularized composite allotransplants in the United States and all the long-term outcome data. We encourage the American Society of Reconstructive Transplantation and the Organ Procurement and Transplant Network committee to embrace the international ethical standards and to hold all vascularized composite allotransplant programs in the United States accountable for reporting data on outcomes of pre-September 2015 transplants.

Narrative methods for assessing "quality of life" in hand transplantation: five case studies with bioethical commentary

Despite having paved the way for face, womb and penis transplants, hand transplantation today remains a small hybrid of reconstructive microsurgery and transplant immunology. An exceptionally limited patient population internationally (N < 200) complicates medical researchers' efforts to parse outcomes "objectively." Presumed functional and psychosocial benefits of gaining a transplant hand must be weighed in both patient decisions and bioethical discussions against the difficulty of adhering to post-transplant medications, the physical demands of hand transplant recovery on the patient, and the serious long-term health risks of immunosuppressant drugs. This paper relates five narratives of hand transplantation drawn from an oral history project to show how narrative methods can and should inform ethical evaluations and the clinical process of hand transplantation. The interviews with patients and their partners analyzed here lead us to suggest that qualitative accounts of patient experiences should be used to complement clinical case studies reported in medical journals and to help develop instruments to assess outcomes more systematically.