Automated red blood cell exchange for acute drug removal in a patient with sirolimus toxicity

State of the Evidence: Drug Removal via Apheresis

Therapeutic apheresis refers to a diversity of procedures in which specific hematologic components (e.g., plasma, erythrocytes, leukocytes, etc.) with pathological associations are removed from circulation (with possible replacement) in order to treat a variety of disease processes. As pharmacologic agents also circulate with these components, their removal is sometimes incidental, or in the scenario of drug toxicity, a therapeutic goal. The corpus of published manuscripts on this subject has grown immensely over the past few decades; however, the breadth of diseases, methods, and drugs that co-exist in this space make it challenging to generate generalizable evidence regarding drug removal via apheresis. This review discusses factors worth considering when interpreting literature-reported data on drug removal by apheresis with examples from several notable studies and highlights topics in need of evidential improvement and growth as our palette of therapeutic agents continues to expand.

Role of automated red blood cell exchange in the treatment of aluminum phosphide poisoning: A case report and review of the literature

Aluminum phosphide (AIP) is a fumigant commonly used in agricultural areas. AIP is frequently misused for suicidal purposes because it is easily accessible. AIP poisoning causes severe metabolic acidosis, resistant hypotension, acute respiratory distress syndrome, and multiorgan failure with cardiogenic shock. Despite supportive management and intensive care, most patients die following AIP ingestion because there is no specific antidote. In this case report we present a 15-year-old female who presented with vomiting, coma and epigastric pain. She developed resistant metabolic acidosis and hypotension due to AIP poisoning. Although supportive treatment did not result in clinical improvement, she was successfully treated with automated red blood cell exchange. Automated red blood cell exchange is a procedure which is used to exchange the patient erythrocyte mass with donor red blood cell. Although automated red blood cell exchange is a preferred treatment method in the complications of sickle cell anemia, some blood diseases and infectious diseases such as malaria and babesiosis, there is little information about its use in poisoning. To the best of our knowledge, this is the first child with AIP poisoning who was treated with automated red blood cell exchange.

Successful management of sirolimus toxicity in a hematopoietic stem cell transplant patient using automated red blood cell exchange

BACKGROUND

Sirolimus is an immunosuppressive agent used in organ rejection prophylaxis in solid-organ transplantation, graft-vs-host disease prophylaxis in hematopoietic stem cell transplantation, and as an immune modulator for patients with lymphangioleiomyomatosis and vascular malformations. Sirolimus has a narrow therapeutic index with potential severe side effects, including hypertension, hepatotoxicity, nephrotoxicity, and neurotoxicity.

CASE REPORT

We report a case of a 19-year-old woman with severe sickle cell disease who underwent a matched unrelated hematopoietic stem cell transplantation, whose course was complicated by sirolimus toxicity. This case was challenging because sirolimus has no specific antidote, is largely bound to red blood cells (RBCs), has a high distribution volume, and cannot be removed by dialysis or plasmapheresis.

RESULT

Due to the concern for toxicity, we looked into possibilities for rapid sirolimus clearance using automated RBC exchange. The treatment was effective in decreasing blood sirolimus levels within the therapeutic ranges.

CONCLUSION

The use of RBC exchange is potentially safe and effective in the management of a case of sirolimus toxicity.