Apheresis for severe malaria complicated by cerebral malaria, acute respiratory distress syndrome, acute renal failure, and disseminated intravascular coagulation

Current evidence and future of automated erythrocyte exchange in the treatment of severe malaria

Despite the administration of antimalarial treatment, severe malaria still has a high mortality rate. Since overall survival is associated with total parasite biomass, whole blood exchange (e.g. blood exchange transfusions) has been proposed as a potential method to rapidly reduce peripheral parasitaemia. Automated red blood cell exchange has been advocated as a physical method to remove parasites. Compared to exchange transfusion, automated red blood exchange may avoid the risk of volume alterations and haemodynamic distress. Since 1984, there have been 37 published cases in which automated red blood cell exchange was used as an adjunctive treatment in severe malaria caused by Plasmodium falciparum. This short review summarizes current evidence and discusses problems, challenges and goals for future studies and research in order to assess the clinical benefit of automated erythrocyte exchange in severe malaria cases.

Therapeutic plasma exchange: an underutilized therapeutic modality?

Since its clinical availability approximately 25 years ago, therapeutic plasma exchange (TPE) has become recognized as appropriate primary therapy for many diverse medical conditions. In some aspects TPE has been constrained in its use according to schedules of efficacy. Expansion of TPE to other indications is likely once attention is focused on its ability to enable patients to avoid potentially toxic pharmacologic interventions if employed as a chronic therapy, and especially when it is accepted that adjunctive use, not only a curative role, is a valuable use of this therapeutic modality.

Clinical application of therapeutic erythrocytapheresis (TEA)

Therapeutic erythrocytapheresis (TEA) has been used in different diseases such as polycythemia vera (PV), secondary erythrocytosis or hemochromatosis as a process of the less cumbersome but more expensive phlebotomy. TEA is preferred in emergency conditions such as thrombocytosis or in conditions such as porphyria cutanea tarda (PCT) or erythropoietic porphyria when plasma exchange (PEX) is often combined with TEA to reduce extracellular levels of uroporphyrin which contribute to plasma hyperviscosity. TEA is often combined with drug therapy that varies from etoposide in PV to EPO and desferoxamine which are used to mobilize and reduce iron stores in hemochromatosis. Benefits from this combination may be more long lasting than expected. Nonetheless for TEA, there is no standard protocol and, clinical experience with this therapy remains highly anecdotal. Therapeutic red cell-exchange (TREX) has been used with much interest over the years, starting with the management of hemolytic disease of the newborn and later used to correct severe anemia in thalassemia patients thereby preventing iron overload. It has also been used for the management of complications of sickle cell disease such as priapism, chest syndrome, stroke, retinal, bone, splenic and hepatic infarction or in preparation for surgery by reducing HbS to less than 30%. Automated apheresis has also favored the use of TREX in conditions such as paroxysmal nocturnal hemoglobinuria and aniline poisoning, arsenic poisoning, Na chlorate intoxications and CO intoxications, hemoglobinopathies, autoimmune hemolytic anemia, reactions due to ABO incompatibility, in preparation for ABO incompatible bone marrow transplantation or for preventing anti-D immunization after the transfusion of D(+) cells to D(-) recipients. Another field of application has been in the emergency management of intraerythrocytic parasite infections such as malaria and babesiosis. Application of TREX may be wide but its real use remains limited. In our personal experience, in 16 years, only 167 TREX procedures have been carried out in a total of 13,747 therapeutic procedures. This represents only 1.21% of the total.

Therapeutic plasma exchange and cytapheresis in pediatric patients

Pediatric therapeutic apheresis is reviewed including what it is, how it is performed and indications for its use. Pediatric patients are special, and the unique needs for replacement fluids and attention to access, anticoagulation, volume shifts and hypothermia are stressed. While all indications cannot be addressed, the procedures most commonly performed are reviewed. These include erythrocytapheresis, leukaphereses and plasma exchanges. A table details the strength of evidence supporting the use of apheresis procedures for many of these indications.