不相容肾移植计划
通常，需要肾脏移植的患者都有活体供体. Unfortunately, many living donors may not have blood or tissue types that match the recipient. If the donor organ does not match the recipient’s blood and tissue, the transplant will fail. 不兼容的 donor/patient pairs may be interested in one of our 不兼容的 肾移植 programs.
在本节中:
血液相容性
Living transplant donors and recipients should have matching or compatible blood types to decrease the risk of organ rejection. 如果你不确定自己的血型, your physician will review this information with you during your evaluation process. 血型取决于红细胞表面的抗原, 并分为A类, B, AB, 或O. 血型是由基因决定的, 所以很可能有一个亲密的家庭成员和你有相同的血型.
交叉配型阳性及致敏患者
大约30%的移植患者是敏感的. This means that they have harmful antibodies which will attack foreign tissue, 比如活体捐献者的移植器官. 这些抗体是通过先前接触外来组织而产生的, 比如怀孕期间, 以前的移植, 或者输血. Sensitized patients may wait three to four times longer than unsensitized patients for a compatible deceased donor kidney.
来检测受体的抗体, a sample of their blood is mixed with a sample of the potential donor’s blood. 这种测试被称为“交叉匹配”,，并显示接受者的抗体与潜在供体的抗体如何反应. 测试结果可以是阳性的也可以是阴性的. 一开始可能会让人感到困惑, but a positive crossmatch means that a donor and recipient are not compatible.
A positive crossmatch results in the recipient’s antibodies attacking the donor’s which means the kidney is not suitable for transplant.
A negative crossmatch means that the recipient’s antibodies do not attack the donor’s which means the kidney is suitable for transplant.
积极的试验:
A positive crossmatch results in the recipient’s antibodies attacking the donor’s which means the kidney is not suitable for transplant.
消极的试验:
A negative crossmatch means that the recipient’s antibodies do not attack the donor’s which means the kidney is suitable for transplant.
If a donor and recipient are not compatible, a transplant can still be performed. Experts at the Johns Hopkins 综合移植中心 developed a method call 血浆置换, which helps make a kidney more compatible for a recipient and significantly affects survival outcomes.
血浆置换
The antibodies in a person’s blood help protect our bodies from foreign objects. 通常，你的抗体保护你免受病毒和细菌的侵害. 然而, 在器官移植的情况下, your antibodies may mistake your new organ as an invading object and try to defend your body from this intruder.
血浆置换 is similar to dialysis; 然而, 它去除血液中抗体所在的血浆部分. 血浆是血液中携带红细胞的几乎透明的部分, 白细胞, 血小板和其他物质通过你的血液. During 血浆置换, you will need to have a working native fistula, graft or dialysis catheter. 如果你有导尿管, one line of the catheter is attached to tubing and takes blood to the 血浆置换 machine. 导管的第二根线用于回流血液. If you have a fistula or graft, needles will be placed as they are for dialysis. 当针扎到位时，你可能会感到轻微的不适. 这与献血者的经历相似.
移植 patients may need to have multiple 血浆置换 sessions before and after surgery to remove antibodies. 此外，患者产生抗体的脾脏也可能被切除.
患者还需要免疫抑制药物. This will be required before transplantation and may be needed following surgery.
什么是配对肾脏交换?
自2001年以来, Johns Hopkins 综合移植中心 has participated in paired kidney exchanges. 配对肾脏交换, also known as a “kidney swap” occurs when a living kidney donor is incompatible with the recipient, 与另一对供体/受体交换肾脏. 将进行两次活体供体移植. Suppose there were two donor/recipient pairs, Donor and Recipient 1 and Donor and Recipient 2:
- 供体1将把一个肾给受体2.
- 然后，供体2将把一个肾脏给受体1.
This kidney paired donation transplant enables two incompatible recipients to receive healthy, 更相容的肾脏. All medically eligible donor/recipient pairs may participate in the paired kidney exchange program.
在更复杂的情况下，可以使用额外的供体/受体对. Participating in the paired kidney exchange program allows for a recipient to receive a better matched kidney, and helps other individuals who would otherwise continue to wait for a matched donor. Approximately 45% of donor/recipient pairs could find a perfectly matched donor by entering the national paired kidney exchange program.
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多年来, matching potential donor/recipient pairs was managed through the local hospital, 或者通过与地区医院合作. 最近, 器官获取和移植网络 started a 肾脏 Paired Donation program that will find matching donor/recipient pairs throughout the United States. 约翰霍普金斯大学的专家们预测到了这一点, 每年, 额外1个,000 – 2,通过这一国家计划，可以进行000次捐赠.
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任何地方都可能需要一个月到两年的时间才能找到一个交换对. 这取决于供体/受体的抗体水平, 血型和数据库里的人数.
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如果手术是两对供体/受体之间的简单交换, the Johns Hopkins 综合移植中心 will typically remove the kidneys from the donors in the morning and transplant to the recipients in the afternoon. 也许有那么几次, 然而, 一个移植手术可能会在另一个移植手术几周后进行. If multiple donor/recipient pairs are involved, the process may take several weeks.
如果有其他医院参与, 捐献者有可能被要求前往他们的所在地. 如果是这样的话, 捐赠者将被指派一名协调员, 这家医院的外科医生和肾病专家. 大多数医院都会接受运送过来的捐赠者的肾脏. 研究 has shown the living donor kidneys can be stored in preservation fluid for up to eight hours and still work effectively. -
Donor/recipient pairs do not meet until after the exchange has taken place and only if each person agrees.
非直接捐赠
Non-directed donors are everyday people who decide to make a difference in the life of a stranger by donating a kidney. 当与不相容连接时, 现有的供体/接受者对, 非定向捐赠引发了肾脏捐赠的多米诺骨牌效应. The combination of non-directed donation and living donation can significantly lower the number of patients on the transplant waiting list.
“Becoming a living kidney donor is a serious decision, with some risks, but many rewards. I couldn't get past the idea that the slim chance that this surgery might affect my quality of life was more than offset by the knowledge that my kidney might mean all the difference to some child who would have no life at all if I backed away.”
约翰·坦普尔，非定向肾捐赠者