Rh(D) Alloimmunization Risk After Rh(D)-Incompatible Solid Organ Transplantations in Rh(D)-Negative Recipients

Area of Science:

• Immunology
• Transplantation Medicine
• Hematology

Background:

• Rh(D)-incompatible solid organ transplantation lacks standardized guidelines for anti-D immunoglobulin (RhIG) prophylaxis.
• The management of Rh(D)-negative recipients undergoing Rh(D)-incompatible transplantation remains an area of clinical uncertainty.

Purpose of the Study:

• To evaluate the necessity and efficacy of RhIG prophylaxis in Rh(D)-negative patients receiving Rh(D)-incompatible solid organ transplants.
• To assess Rh alloimmunization rates and clinical outcomes, including graft function and survival, in this patient population.

Main Methods:

• Retrospective review of 35 Rh(D)-negative patients who underwent Rh(D)-incompatible solid organ transplantation.
• Patients were categorized into RhIG-administered and non-administered groups.
• Monitoring included antibody screening, graft function assessment (serum creatinine/bilirubin), and biopsy for suspected rejection.

Main Results:

• No cases of anti-D alloimmunization were detected in the RhIG non-administered group (n=16).
• A statistically significant increase in rejection episodes was observed in the RhIG-administered group among kidney transplant recipients (P = .0278).
• Median follow-up was 60 months, with a median recipient age of 48.5 years.

Conclusions:

• The low incidence of Rh(D) alloimmunization is likely attributed to the immunosuppressive environment post-transplantation.
• RhIG prophylaxis does not appear to offer clinical benefits in Rh(D)-incompatible solid organ transplantation.
• Current findings suggest a re-evaluation of RhIG prophylaxis protocols in this specific transplant context is warranted.