Use of therapeutic plasma exchange for pediatric neurological diseases.

Therapeutic plasma exchange is used to treat neurological diseases in the pediatric population. Since its first use in pediatric patients with hepatic coma in the form of manual whole blood exchange, therapeutic plasma exchange has been increasingly used to treat these disorders of the nervous system. This expansion is a result of improved techniques and apheresis instruments suitable for small children, as well as the recognition of its applicability to many diseases in the pediatric population. This review provides a historical overview of the use of therapeutic apheresis in children and highlights the most common applications for therapeutic plasma exchange to treat neurological disorders in children.

Iron Deficiency Anemia in Patients Undergoing Extracorporeal Photopheresis for Cutaneous T-Cell Lymphoma.

OBJECTIVE: To describe the indicidence and severity of iron deficiency anemia (IDA) in patients who have received extracorporeal photopheresis (ECP) treatment of cutaneous T-cell lymphoma (CTCL). METHODS: We performed a retrospective study during a 9-year period of patients with CTCL who were treated with ECP. ECP was performed with UVAR XTS and CELLEX (Therakos Inc). IDA was defined by a drop in hemoglobin (Hb), mean cell volume (MCV), and increased red blood cell distribution width (RDW). RESULTS: We identified a total of 36 patients; 1 patient was excluded due to severe anemia. In 35 patients, initial hemoglobin values ranged from 9.8 g per dL to 15.9 g per dL, and patients received 4 to 327 ECP treatments. In all, 28 patients showed decreases in Hb of 0.8 g per dL to 6 g per dL during treatments. CONCLUSION: Chronic ECP led to IDA in 28 of 35 patients with CTCL. IDA occurs due to blood loss when ECP equipment does not return full blood volume to patients.

Impact of high dose vitamin C on platelet function.

AIM: To examine the effect of high doses of vitamin C (VitC) on ex vivo human platelets (PLTs). METHODS: Platelet concentrates collected for therapeutic or prophylactic transfusions were exposed to: (1) normal saline (control); (2) 0.3 mmol/L VitC (Lo VitC); or (3) 3 mmol/L VitC (Hi VitC, final concentrations) and stored appropriately. The VitC additive was preservative-free buffered ascorbic acid in water, pH 5.5 to 7.0, adjusted with sodium bicarbonate and sodium hydroxide. The doses of VitC used here correspond to plasma VitC levels reported in recently completed clinical trials. Prior to supplementation, a baseline sample was collected for analysis. PLTs were sampled again on days 2, 5 and 8 and assayed for changes in PLT function by: Thromboelastography (TEG), for changes in viscoelastic properties; aggregometry, for PLT aggregation and adenosine triphosphate (ATP) secretion in response to collagen or adenosine diphosphate (ADP); and flow cytometry, for changes in expression of CD-31, CD41a, CD62p and CD63. In addition, PLT intracellular VitC content was measured using a fluorimetric assay for ascorbic acid and PLT poor plasma was used for plasma coagulation tests [prothrombin time (PT), partial thrombplastin time (PTT), functional fibrinogen] and Lipidomics analysis (UPLC ESI-MS/MS). RESULTS: VitC supplementation significantly increased PLTs intracellular ascorbic acid levels from 1.2 mmol/L at baseline to 3.2 mmol/L (Lo VitC) and 15.7 mmol/L (Hi VitC, P < 0.05). VitC supplementation did not significantly change PT and PTT values, or functional fibrinogen levels over the 8 d exposure period (P > 0.05). PLT function assayed by TEG, aggregometry and flow cytometry was not significantly altered by Lo or Hi VitC for up to 5 d. However, PLTs exposed to 3 mmol/L VitC for 8 d demonstrated significantly increased R and K times by TEG and a decrease in the α-angle (P < 0.05). There was also a fall of 20 mm in maximum amplitude associated with the Hi VitC compared to both baseline and day 8 saline controls. Platelet aggregation studies, showed uniform declines in collagen and ADP-induced platelet aggregations over the 8-d study period in all three groups (P > 0.05). Collagen and ADP-induced ATP secretion was also not different between the three groups (P > 0.05). Finally, VitC at the higher dose (3 mmol/L) also induced the release of several eicosanoids including thromboxane B2 and prostaglandin E2, as well as products of arachidonic acid metabolism via the lipoxygenases pathway such as 11-/12-/15-hydroxyicosatetraenoic acid (P < 0.05). CONCLUSION: Alterations in PLT function by exposure to 3 mmol/L VitC for 8 d suggest that caution should be exerted with prolonged use of intravenous high dose VitC.

Extracorporeal photopheresis: clinical use so far.

Extracorporeal photopheresis (ECP or photopheresis) is an advanced therapeutic apheresis procedure in which blood is separated into its various components and the isolated buffy coat is treated with 8-methoxypsoralen (a photoactivating drug), exposed to ultraviolet light and returned to the patient. All other remaining blood components are also returned to the patient. The purpose of this procedure is immunomodulation. The treated leukocytes, specifically T-cells, are returned to the patient's circulation and will induce cytotoxicity and reduce proliferation of new T-cells. In the United States, ECP was initially approved for the treatment of cutaneous T-cell lymphoma by the US Food and Drug Administration in the late 1980s. Since that time, it has been used as an "off-label" therapy to treat several other autoimmune diseases in the United States and even more extensively in Europe and Asia. The following review is limited to the current clinical use of ECP in cutaneous T-cell lymphoma, Crohn's disease, systemic sclerosis, graft versus host disease, and emerging data on nephrogenic systemic fibrosis.

Therapeutic apheresis in critically ill patients.

Therapeutic apheresis procedures in critically ill patients comprises of therapeutic plasma exchange in most cases but also less commonly, erythrocytapheresis (red cell exchange), thrombocytapheresis, or leukocytapheresis. These procedures present a number of challenges to the apheresis healthcare team, and there are myriad beneficial and adverse effects for patients. In this patient population, one has to weigh the risks against the benefits and especially in those situations where apheresis is requested as a treatment when other alternative therapies have failed. Therapeutic plasma exchange is capable of removing toxins, pathologic auto- and allo-antibodies but will also remove beneficial medications, clotting factors and cations which are chelated by citrate anticoagulant. Herein, we review clinically significant issues that are commonly encountered in patients that are in the intensive care unit and have conditions that require therapeutic apheresis.

Investigation of heparin-related hypotensive adverse events during photopheresis: utility of a patient care database.

BACKGROUND: Extracorporeal photopheresis (ECP) is a procedure in which leukocytes are harvested from a patient's whole blood, treated with a DNA binding dye and ultraviolet light to inactivate lymphocytes, and then returned into the patient's circulation. In January 2008, we observed moderately severe anaphylactoid reactions in eight of 16 patients undergoing ECP. CASE STUDY: Each affected individual exhibited hypotension of sudden onset, usually with tachycardia, during the return of heparin-anticoagulated blood at the end of the first cycle of collection of leukocytes. A systematic investigation of possible contributing factors revealed that all reactions were associated with administration of a single new lot of heparin. RESULTS: Changing to a different manufacturer of heparin eliminated the occurrence of further such hypotensive reactions during ECP. Although the symptoms were initially attributed to vasovagal reactions or dehydration, their temporal association with exposure to a new lot of heparin suggested a procedure-related phenomenon. Of particular note, was the finding that of the eight patients who had reactions at any time, six had initial exposures without reactions, suggesting a process of sensitization. CONCLUSION: This study demonstrated the value of a patient database listing lot numbers of all medications and components used in each routine ECP procedure for facilitating rapid determination of common patient exposures, making it easier to determine the cause of adverse events, in this case, a particular lot of heparin responsible for the hypotensive adverse events.

Fecal occult blood testing.

Colorectal cancer (CRC) is the third most common cancer in the United States. A reduction in cumulative mortality occurs when patients are routinely screened by fecal occult blood tests (FOBT) and early lesions are removed. These point-of-care tests detect minute amounts of blood released from precancerous and cancerous colon lesions. Positive test results should be followed up with complete diagnostic testing to treat precancerous lesions and diagnose patients at earlier stages of cancer, thereby increasing overall survival. More complex assays are designed to detect genetic changes in cells released from malignant and even premalignant lesions. This article provides information on the screening and diagnostic tests available for CRC detection as well as the advantages and disadvantages of each.