Do you remember that I popularized the indications of kidney transplantation for ABO-incompatible relatives on March 15? (Are you suitable for kidney transplantation for ABO-incompatible relatives?) Today, I will continue to lead you to understand several issues that need to be paid attention to before kidney transplantation for ABO-incompatible relatives.
First, let’s briefly review the indications and contraindications of kidney transplantation for ABO-incompatible relatives: It is suitable for patients with end-stage renal disease. Its indications and contraindications are basically similar to those of kidney transplantation for ABO-compatible blood type, especially for patients with uremia who are difficult to find ABO-compatible kidney sources in a short period of time, have poor dialysis treatment effects, or have many complications, are life-threatening, and cannot accept other renal replacement therapies.
Then, let’s take a look at the preoperative preparation for ABO blood type incompatible relatives’ kidney transplant recipients. The most noteworthy thing is that the recipient’s blood type antibody titer needs to be reduced through plasma exchange, rituximab, and routine use of immunosuppressants before the operation. The transplantation requirements for anti-A and anti-B antibody blood type antibody titers on the day of transplantation are: adult recipients IgM≤1∶16, IgG≤1∶16; children recipients IgM≤1∶64, IgG≤1∶64[1]. If the initial blood type antibody titer is higher than the target titer, plasma exchange is performed to reach the target titer; for recipients with lower blood type antibody titers and who meet the antibody titer requirements on the day of transplantation, plasma exchange can be omitted; the dose of rituximab is determined based on the recipient’s CD19+ cell value before the operation.
Here, we will continue to popularize the relevant knowledge of rituximab. Rituximab is a chimeric mouse anti-human CD20 monoclonal antibody. CD20 is expressed on normal human initial B cells and mature B cells. Therefore, the use of rituximab can reduce the proportion of B cells that produce antibodies and become a routine preoperative treatment measure. Of course, the routine use of immunosuppressants is also necessary. In our center, recipients start taking oral maintenance doses of triple immunosuppressants (tacrolimus + MPA + prednisone) 2 weeks before surgery, and patients with high antibody titers start 3 to 4 weeks before surgery (more plasma exchange). In addition, since coagulation system dysfunction can cause complications such as bleeding and embolism, the patient’s coagulation function status is also a point that needs special attention before surgery. At present, the coagulation function requirements on the day of surgery are: activated partial thromboplastin time (APTT) is 24 to 46 seconds; plasma thrombin time (TT) is 11 to 21 seconds; fibrinogen (FIB) is 1.2 to 4 g/L; D-dimer is <0.3 mg/L[2].
Seeing this, if you still have many questions in your mind, then you can take a closer look at the article “Exploration of Individualized Pretreatment of Recipients of ABO-Incompatible (ABOi) Relative Kidney Transplantation” published by our center’s chief physician Rong Ruiming in the “Fudan Journal” in January 2020. I believe you can gain more.