Haewon C. Kim

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice—Evidence-Based Approach from the Apheresis Applications Committee of the American Society for Apheresis

The American Society for Apheresis (ASFA) Apheresis Applications Committee is charged with a review and categorization of indications for therapeutic apheresis. Beginning with the 2007 ASFA Special Issue (fourth edition), the subcommittee has incorporated systematic review and evidence‐based approach in the grading and categorization of indications. This Fifth ASFA Special Issue has further improved the process of using evidence‐based medicine in the recommendations by refining the category definitions and by adding a grade of recommendation based on widely accepted GRADE system. The concept of a fact sheet was introduced in the Fourth edition and is only slightly modified in this current edition. The fact sheet succinctly summarizes the evidence for the use of therapeutic apheresis. The article consists of 59 fact sheets devoted to each disease entity currently categorized by the ASFA as category I through III. Category IV indications are also listed. J. Clin. Apheresis, 2010.

Role of Plasmapheresis in the Management of Acute Hepatic Failure in Children

ObjectiveTo assess the efficacy of plasmapheresis in the treatment of children with acute hepatic failure. Summary Background DataAcute liver failure is expressed with severe encephalopathy, coagulopathy, and subsequent multisystem organ failure, resulting in a high death rate. Liver transplantation is considered the best option, with long-term 1-year survival rates exceeding 88%. It has been suggested that plasmapheresis may improve coagulopathy and prevent bleeding complications while maintaining adequate fluid, electrolyte, and acid–base balance. MethodsForty-nine patients with acute liver failure underwent a total of 243 therapeutic plasma exchanges (TPE). Indications for treatment included candidacy for liver transplant and prolonged prothrombin time. Pheresis was performed daily until the patient recovered, died, or was transplanted. Four patients were anhepatic during pheresis. ResultsCoagulation profiles after TPE significantly improved compared with mean preexchange values while maintaining euvolemia. No bleeding episodes were observed during the course of treatment. There was no sustained improvement in neurologic function. Spontaneous recovery was observed in three patients; the remaining either underwent transplantation (32/49) or were not considered transplant candidates because of irreversible neurologic insults (11/49) or sepsis (3/49). ConclusionFor children with acute liver failure, TPE is extremely effective in preventing life-threatening bleeding while maintaining appropriate volume status in small children. This method of treatment has no effect on the neurologic complications of liver failure and has no impact on the ability of the liver to regenerate.

Differentiation of bone and bone marrow infarcts from osteomyelitis in sickle cell disorders.

To determine whether imaging techniques can differentiate osteomyelitis from bone infarction in sickle cell disorders, 39 sets of bone scans (BS) and bone marrow scans (BMS) were performed on 31 patients with sickling disorders and bone pain. In addition, three patients who had either a BS or a BMS were included. Results were analyzed according to whether scans were performed three days or less (Period 1), four to six days (Period 2), or seven or more days (Period 3) after the onset of pain. Regardless of the period, all but five BMS for 34 episodes of assumed infarction showed decreased uptake. BS findings varied depending on the time interval, with none of the ten in Period 1 showing increased uptake, but all 11 in Period 3 showing increased uptake. However, in Period 2, about half of the 13 BS showed increased uptake. All three patients with osteomyelitis in Period 3 had increased uptake on BS. The BMS done in one of these patients showed decreased uptake. Three patients with cellulitis had normal BS and BMS. One patient with septic arthritis had normal BMS, but slightly increased uptake on BS. Although typical imaging patterns are present in early and late infarction (Periods 1 and 3), the patterns for late infarction may not differ from those of advanced osteomyelitis. Therefore, imaging studies are only of value in differentiating infarction from osteomyelitis when both BS and BMS are performed soon after the appearance of symptoms.

Effect of erythrocytapheresis on arterial oxygen saturation and hemoglobin oxygen affinity in patients with sickle cell disease

An important purpose of blood transfusion in patients with sickle cell disease is to improve arterial oxygen saturation (SaO2) and thereby reduce red cell sickling. To investigate the degree of improvement in SaO2 by blood transfusion, we determined the hemoglobin oxygen affinity, transcutaneous oxygen saturation (Tc‐SO2), and pulse rate before and after automated partial exchange transfusion (erythrocytapheresis). In 13 patients with sickle cell disease who underwent 24 erythrocytapheresis procedures, the mean oxygen tension at half saturation (P50) was significantly reduced from 30.4 ± 2.2 to 26.0 ± 1.6 mm Hg (P < 0.01) immediately after exchange transfusion. Mean Tc‐SO2 values increased from 96.2 ± 2.8 to 98.5 ± 2.1% (P < 0.01). Approximately 50% of the increase in Tc‐SO2 after erythrocytapheresis could be explained by the increase in hemoglobin oxygen affinity. An increase in arterial oxygen pressure (PaO2) following erythrocytapheresis, suggested by the calculated PaO2 in this study, may explain some of the increase in Tc‐SO2. We conclude that improvement in Tc‐SO2 in patients with sickle cell disease resulted from changes in hemoglobin oxygen affinity as well as blood oxygen pressure following erythrocytapheresis. Am. J. Hematol. 59:5–8, 1998.

Red cell exchange: special focus on sickle cell disease

The primary function of red blood cells (RBCs) is to deliver oxygen from the lungs to tissues. Tissue hypoxia occurs when the oxygen-carrying capacity of RBCs is compromised due primarily to 3 causes: (1) a reduction in circulating RBC mass, (2) an increase in circulating RBC mass, or (3) abnormal hemoglobin (Hb) that either does not sufficiently release oxygen to tissues (high-oxygen-affinity hemoglobin) or occludes the microvasculature due to deformed RBCs (sickled RBCs). To improve oxygenation in patients with reduced or increased RBC mass, RBC administration (simple transfusion) or RBC removal (RBC depletion) is performed, respectively. However, for patients with abnormal Hb, RBCs containing abnormal Hb are removed and replaced by healthy volunteer donor RBCs by red cell exchange (RCE). RCE can be performed by manual exchange or by automated exchange using a blood cell separator (erythrocytapheresis). In this review, indications for RCE in sickle cell disease using the evidence-based American Society for Apheresis categories(1) are presented and the rationale for RCE in each disorder are discussed. Simple transfusion versus RCE and manual RCE versus automated RCE are compared. Finally, this review briefly presents some of the challenges of performing erythrocytapheresis in small children and discusses various choices for central venous access during RCE.(2.)

Life-threatening complications in a child with hemoglobin SD-Los Angeles disease.

Hemoglobin SD-Los Angeles is an uncommon sickle hemoglobinopathy. We describe a boy with documented Hb SD-Los Angeles who had experienced acute splenic sequestration, pneumococcal sepsis, aplastic crisis and functional asplenia during his first two years of life. We suggest that children with Hb SD-Los Angeles are at similar risks for the life-threatening complications which characterize sickle cell anemia and should receive the same comprehensive medical care currently recommended for children with Hb SS disease.

Childhood-onset familial porphyria cutanea tarda: Effects of therapeutic phlebotomy

Cutaneous fragility at age 2 years with blistering, scarring, milia, and hypertrichosis at age 4 years were noted in an otherwise healthy girl who had no family history of porphyria. Results of porphyrin analyses of urine, serum, and red blood cells revealed a pattern consistent with porphyria cutanea tarda. Red blood cell uroporphyrinogen decarboxylase activity was diminished to approximately 50% of normal in the child and in her mother and maternal grandmother, who were without symptoms; activity was normal in her sister, father, and maternal grandfather. Therapeutic phlebotomies were followed by a biochemical and clinical remission.

Extracorporeal photopheresis practice patterns: An international survey by the ASFA ECP subcommittee

Although many apheresis centers offer extracorporeal photopheresis (ECP), little is known about current treatment practices.

Report of the ASFA apheresis registry study on Wilson's disease

Wilsons disease is a rare autosomal recessive genetic disorder that results in accumulation of copper in the liver, brain, cornea and kidney. Therapeutic plasma exchange (TPE) has been used to remove copper and provide a bridge to liver transplantation. We report here the collective experiences through the ASFA apheresis registry on Wilsons disease.

The presurgical management with erythrocytapheresis of a patient with a high-oxygen-affinity, unstable Hb variant (Hb Bryn Mawr)

BACKGROUND: Hemoglobin (Hb) Bryn Mawr is an unstable Hb variant resulting in congenital hemolytic anemia. This variant Hb also has an increased affinity for oxygen. The perioperative transfusion management of this disorder is described, and the first genomic analysis of this Hb variant is given. CASE REPORT: An 11‐year‐old boy, heterozygous for Hb Bryn Mawr, was referred for cholecystectomy. Sequence analysis of genomic DNA confirmed that the patients was heterozygous for a T–>C transition in the codon for amino acid 85, causing a substitution of serine for phenylalanine in the beta‐globin chain. On the basis of whole‐blood O2 dissociation studies, projected tissue O2 delivery would have been suboptimal during general anesthesia; therefore, a partial red cell exchange transfusion was performed to lower variant Hb and prevent tissue hypoxia during surgery. The red cell mass to be exchanged (50%) was determined from the calculated increase in O2 delivery capacity required to maintain an O2 extraction of 4 to 5 mL of O2 per dL of whole blood. The p50 of whole blood from the patients immediately after the exchange transfusion was 16.0 torr. At the time of surgery, the p50 was normal (25.9 torr). The patients whole blood 2,3 DPG levels were 4.70 mmol per mL of red cells (before transfusion) (normal range=4.8 +/− 0.3 mmol/mL red cells), 4.07 mmol per mL of red cells (immediately after transfusion), and 4.55 mmol per mL of red cells (48 hours after transfusion). CONCLUSION: This patient with Hb Bryn Mawr was prepared for surgery with a partial exchange transfusion to prevent tissue hypoxia during anesthesia. Decreased 2,3 DPG levels immediately after transfusion resulted in increased O2 affinity of whole blood; however, 48 hours after exchange transfusion, a normal p50 (due to both removal of variant Hb and regeneration of 2,3, DPG) was observed. Partial exchange transfusion is useful in the preoperative management of patients with Hb variants characterized by increased O2 affinity.