Antithymocyte globulin-induced refractory hypotension in renal transplantation recipient

Risk factors and outcomes of persistent post-transplant hypotension among simultaneous pancreas and kidney transplant recipients

BACKGROUND

The risk factors and outcomes associated with post- transplant hypotension after simultaneous pancreas and kidney (SPK) Transplantation are poorly defined.

METHODS

SPK recipients at our center between 2010 and 2021 with functioning pancreas and kidney grafts for >6 months were included. Recipients were then divided into three groups based on active medications for the treatment of hypo-or hypertension at 6-months post-transplant: those with normal blood pressure (NBP) not requiring medication (NBP group), those on antihypertensive medications (HTN group), and those on medications for hypotension (fludrocortisone and/or midodrine) (Hypotensive group).

RESULTS

A total of 306 recipients were included in the study: 54 (18%) in the NBP group, 215 (70%) in the HTN group, and 37 (12%) in the Hypotensive group. On multivariate analysis, the use of T-depleting induction (aHR = 9.64, p = .0001, 95% Cl = 3.12-29.75), pre-transplant use of hypotensive medications (aHR = 4.53, p = .0003, 95% Cl = 1.98-10.38), and longer duration of dialysis (aHR = 1.02, p = .01, 95% Cl = 1.00-1.04) were associated with an increased risk of post-transplant hypotension. Post-transplant hypotension was not associated with an increased risk of death-censored kidney or pancreatic allograft failure, or patient death.

CONCLUSION

Hypotension was common even 6 months post-SPK transplantation. With appropriate management, hypotension was not associated with detrimental graft or patient outcomes.

What Therapeutic Regimen Will Be Optimal for Initial Clinical Trials of Pig Organ Transplantation?

We discuss what therapeutic regimen might be acceptable/successful in the first clinical trial of genetically engineered pig kidney or heart transplantation. As regimens based on a calcineurin inhibitor or CTLA4-Ig have proved unsuccessful, the regimen we administer to baboons is based on induction therapy with antithymocyte globulin, an anti-CD20 mAb (Rituximab), and cobra venom factor, with maintenance therapy based on blockade of the CD40/CD154 costimulation pathway (with an anti-CD40 mAb), with rapamycin, and a corticosteroid. An anti-inflammatory agent (etanercept) is administered for the first 2 wk, and adjuvant therapy includes prophylaxis against thrombotic complications, anemia, cytomegalovirus, and pneumocystis. Using this regimen, although antibody-mediated rejection certainly can occur, we have documented no definite evidence of an adaptive immune response to the pig xenograft. This regimen could also form the basis for the first clinical trial, except that cobra venom factor will be replaced by a clinically approved agent, for example, a C1-esterase inhibitor. However, none of the agents that block the CD40/CD154 pathway are yet approved for clinical use, and so this hurdle remains to be overcome. The role of anti-inflammatory agents remains unproven. The major difference between this suggested regimen and those used in allotransplantation is the replacement of a calcineurin inhibitor with a costimulation blockade agent, but this does not appear to increase the complications of the regimen.

Severe anti-thymocyte globulin-induced cytokine release syndrome in a renal transplant patient

Cytokine release syndrome is a systemic inflammatory response that can be triggered by a variety of factors such as infection or exposure to certain drugs, particularly novel T cell-engaging immunotherapies. Severe cytokine release syndrome as a complication following treatment with anti-thymocyte globulin, although recognised, is not well-reported in the literature. We report the case of a 64-year-old man who developed catastrophic cytokine release syndrome after receiving anti-thymocyte globulin during kidney transplantation. We highlight the importance of prompt recognition of severe cytokine release syndrome with strategies to aid survival in life-threatening cases.