The Association between Peri-Transplant RBC Transfusion and Graft Failure after Kidney Transplantation: A Nationwide Cohort Study

Background: Patients undergoing kidney transplantation (KT) often receive red blood cell (RBC) transfusion during admission for KT which may increase the risk of allosensitization. The association between peri-transplant RBC transfusion and graft survival was evaluated using a nationwide cohort. Methods: This retrospective study analyzed 13,871 patients who underwent KT in Korea between 2007 and 2015. The outcomes were graft failure rate and overall patient survival depending on the amount of RBC transfusion. Results: The overall graft failure rate was 15.5%. Compared to the graft failure rate of 13.5% in the no transfusion group, the graft failure rate was 15.4% in the 1–2 units group (sHR 1.06 (95% CI 0.97–1.17), p = 0.216), 21.4% in the 3–5 units group (sHR 1.39 (1.21–1.61), p < 0.001), and 35.3% in the 6 or more units group (sHR 2.20 (1.70–2.85), p < 0.001). The overall survival rate was 97.5% in the no transfusion group, compared to 95.9% in the 1–2 units group (HR 1.50 (1.22–1.83), p < 0.001), 92.0% in the 3–5 units group (HR 2.43 (1.87–3.15), p < 0.001), and 67.5% in the 6 or more units group (HR 6.81 (5.03–9.22), p < 0.001). Conclusions: Peri-transplant RBC transfusion was independently associated with the increased risk of renal allograft failure and death in KT patients.

Nocardiosis in renal transplant patients

Renal transplant patients are immunosuppressed and are at increased risk of opportunistic infections, including Nocardia infection. In renal transplant patients, information on the incidence and risk factors associated with nocardiosis is limited. To address the incidence and risk factors associated with nocardiosis in a large renal transplant population, we used the US Renal Data System (USRDS). Sequelae of allograft failure or rejection after infection were also examined. Demographics, clinical risk factors, Nocardia diagnosis, and allograft failure following Nocardia infection were queried in USRDS renal transplant patients using International Classification of Diseases, Ninth Revision (ICD-9) codes in billing claims and Centers for Medicare and Medicaid Services Form 2728. Generalized linear models were used to determine the risk factors associated with nocardiosis, and Cox proportional hazards models were used to examine the association of risk factors with graft failure among patients with Nocardia infection. Of 203,233 renal transplant recipients identified from 2001 to 2011, 657 (0.32%) were diagnosed with Nocardia infection. Pneumonia was the most frequent presentation (15.2%), followed by brain abscess (8.4%). Numerous factors associated with increased Nocardia infection included age >65 years (OR=2.10, 95% CI 1.71 to 2.59), history of transplant failure (OR=1.28, CI 1.02 to 1.60) or history of rejection (OR=4.83, CI 4.08 to 5.72), receipt of a deceased donor transplant (OR=1.23, CI 1.03 to 1.46), and treatment with basiliximab (OR=1.25, CI 1.00 to 1.55), cyclosporine (OR=1.30, CI 1.03 to 1.65), tacrolimus (OR=2.45, CI 2.00 to 3.00), or thymoglobulin (OR=1.89, CI 1.59 to 2.25). In patients with nocardiosis administration of antithymocyte globulin (HR=2.76), chronic obstructive pulmonary disease (HR=2.47), and presentation of Nocardia infection with brain abscess (HR=1.85) were associated with an increased risk of graft failure. This study provides new information to enhance early recognition and targeted treatment of nocardiosis in renal transplant patients.

Association Between Meniscal Allograft Tears and Early Surgical Meniscal Allograft Failure

Background: Meniscal allograft transplantation (MAT) has become a viable treatment option for patients with symptomatic meniscal deficiency. Some patients experience early surgical meniscal allograft failure attributed to causes that have not yet been sufficiently clarified. Purpose: To evaluate the prevalence, types, and distribution of arthroscopically confirmed meniscal allograft tears and the associated effect on surgical meniscal allograft survival. Study Design: Cohort study; Level of evidence, 3. Methods: Patients undergoing MAT with a minimum 2-year follow-up were retrospectively reviewed. Descriptive and surgical data were collected. Type and location of arthroscopically confirmed meniscal allograft tears were recorded and compared between medial and lateral allografts and suture-only and bone block fixation. A survival analysis was conducted to evaluate the effect of meniscal allograft tears on surgical meniscal allograft survival. Results: This study included 142 patients (54% male; mean ± SD age, 29.6 ± 10.4 years) with a mean follow-up of 10.3 ± 7.5 years. The prevalence of meniscal allograft tears was 32%, observed at a median of 1.2 years (interquartile range, 2.8 years) after MAT. The posterior horns were most frequently affected, followed by the posterior roots, midbodies, anterior horns, and anterior roots. The most frequently observed tear types were root tears (43%), followed by longitudinal, horizontal, radial, complex, bucket-handle, and meniscocapsular separation tears. A statistically significant association was found between meniscal allograft tear types and fixation techniques ( P = .027), with root tears predominant after suture-only as compared with bone block fixation (57% vs 22%). Patients with meniscal allograft root tears were a mean of 5.4 years (95% CI, 1.6-9.2 years; P = .007) younger than were patients without root tears. The 1-year surgical meniscal allograft survival rate was significantly lower for torn versus intact meniscal allografts (75% vs 99%; P < .001). Conclusion: Meniscal allograft root tears were predominant, associated with younger patient age, and more often observed when using the suture-only fixation technique versus the bone block fixation technique. Torn meniscal allografts were associated with early surgical graft failure when compared with intact meniscal allografts, resulting in a significantly lower 1-year survival rate.