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Per journal article "peripheral blood stem cell mobilization and collection in pediatric healthy sibling donors weighing 20 kilograms or less; algerian experience" by benakli, et al peripheral blood stem cells (pbsc) are the source of allogeneic hematopoietic stem cell transplants currently used for malignant and non-malignant hematological diseases.Pbsc harvest may be difficult in young children who are donors.Extracorporeal separator line priming by red blood cells or albumin alone is usually required to improve haemodynamic tolerance and efficacy of collection.We present our experience with 29 children weighing 20 kg or less mobilised between on (b)(6) 2005 and (b)(6) 2018.The median age and weight at the time of apheresis were 5 years and 18 kg, respectively.A total of 54 pbsc were performed.The median cell yield per apheresis was 5.9 × 106 cd34+cells/kg (2,5-13,9) recipient body weight (rbw).Despite their low weight, insertion of a femoral catheter was avoided in 58.6% of children.Nineteen donors required 2 or 3 apheresis sessions without any major complication.Twenty-nine pts with hemopathies have successfully benefited from pbsc except one case of rejection with aplastic anemia.Morbidity related to pbsc collections was low.Transient hypotension during the procedure required intravenous fluids in 3 cases (10,3%).Ten children (34,4%) developed symptomatic hypocalcemia corrected by calcium injection." section 3.2 (complications related to apheresis), page 3 there were 6 instances reported for intravenous diazepam, 3 instances of vasovagal rxn for transient hypotension, and 10 instances of citrate rxn for calcium injection.Specific details, such as patient information and outcome, were not included in the article for these events, therefore this report is being provided as a summary of the events.The collection set is not available for return because it was discarded by the customer.
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This report is being filed to provide additional information in h.11.Investigation: pbsc mobilization was performed by administration of g-csf (10 g/kg once daily) for 4 consecutive days and collection was started on day 5.A target cd34+ cell dose of at least 4.106/kg of rbw was considered as a criteria to complete collection.In cases in which a second or third procedure was needed, the fifth and sixth additional g-csf doses were administered immediately after the first apheresis at days 5 and 6.Blood processed during apheresis was returned to the child either via a central venous catheter (cvc) or a peripheral vein, depending on the state of the peripheral veins in each case.For this reason, donors should be carefully evaluated and the catheter placed by a well-trained pediatric physician.Some donors received an inhaled general anesthesia for cvc placement and others had conscious sedation.Before beginning, local antiseptic treatment with povidone iodine was performed to prevent infections in the puncture site.The extracorporeal line was primed with high molecular weight starch or albumin, using a priming volume of about 100¿150 ml to mitigate hemodynamic complications.Blood priming was not systematically performed.Transfusion of leukocyte-depleted phenotyped irradiated packed red blood cells was performed if the haemoglobin was less than 10 g/dl before the second or third harvests.During apheresis, slight sedation was used in donors who were agitated or uncooperative.The children were entertained by the presence of a parent in the room during collection and connected to a monitor to observe their blood pressure, oxygen saturation and heart rate.Pbsc were collected using a continuous flow blood cell separator (cobe spectra® or optia, terumo-bct, usa) with the mononuclear cell (mnc) program.Acid¿citrate¿dextrose (acd-a) was used as anticoagulant (acda ratio of 1/12 to 1/16 based on the patient weight and anticoagulant rate (ac) of 1.2 to 1.6 ml/min).We adjusted the acda ratio and ac rate when needed to get a good inlet rate for the patient.To prevent hypocalcaemia, prophylactic calcium gluconate was administered continuously in a ratio of 1 ml per 200 ml of blood processed.Large volume leukapheresis was defined as processing at least three times the donor blood volume.Viable collection cd34 cell counts were performed using a single-platform method based on the ishage gating strategy using a facscanto flow cytometer (bd, san jose, ca).3.Results between january 2005 and december 2018, pbsc were collected from 29 healthy donors (17 boys and 12 girls) weighing 20 kg or less.Demographic characteristic are shown in table 1.The median age at the time of apheresis was 5 years (range: 3¿9 years) and the median weight was 18 kg (range: 13¿20 kg).A total of 54 pbsc collections was performed in those 29 donors (table 2).A single apheresis was sufficient to obtain the required cell number in 10 cases (34,4%).Two apheresis were performed on consecutive days in 13 cases (44,8%) and 3 apheresis were performed in 6 cases (20,6%).During the apheresis procedure, 6 (20,6%) children required sedation with low dose of intravenous diazepam due to uncooperativeness.Prior to pbsc collection, after mobilization, the mean of white blood cell count was 49,3.106/l (range: 27,5-93,3) and blood line priming was not performed.Five donors (17%) received transfusions of red blood cells before the second or third harvests.Insertion of a femoral central venous line was necessary in 17 children (58,6%).No child experienced any collection-related occlusion or infection.The blood volume (bv) processed during the apheresis procedure, and the volume of the final product collected were 5964 ml (range: 2709-10583) and 195 ml (range: 100-351), respectively.The median duration of the apheresis per donor, was 223 min (range: 115-351) with a median blood flow rate of 25 ml/min (range: 20-50) using a median acd-a of 375 ml (range: 128-717).The median cd34+ cell count collected per child was 5,9 × 106/kg rbw (0,58¿24,64) of whom 18 donors (62%) achieved the target cd34+ cell dose of more than 4.106/kg and 27 donors (93%) more than 2.106/ kg.Males had a higher mean collected cd34+ cell yield (= 4.106/kg) than females (82% vs 33%).The mean ratio between donor and recipient (d/r) body weight was 0,74 (0,25-1,36).Donors with this ratio < 1 failed to reach cd34+ cell dose > 4.106/kg.Morbidity related to pbsc collections was low.Transient hypotension during the procedure required intravenous fluids in 3 cases (10,3%).Ten children (34,4%) developed symptomatic hypocalcaemia corrected by calcium injection.No child experienced any collection-related infection.The median value of lowest hemoglobin and platelet concentration reported after harvest were 10 g/dl (range: 6,7-12,9) and 143 × 109/l (86-363), respectively.Thrombocytopenia less than 100 × 109/l was seen in one donor (3%) and anemia with less than 10 g/dl hemoglobin level observed in 13(44,8%) donors.Apart from 3 donors (10%), all expressed their willingness to donate again.A request for lot numbers is not feasible because there are many months between collection of data, to peer review, to final publication.Therefore, a dhr search could not be conducted for this specific incident.All lots must meet acceptance criteria for release.According to therapeutic apheresis: a physician's handbook, adverse events occur during therapeutic procedures with a frequency of 4.8%.Some of the most common reactions include fever, urticaria, hypocalcemic symptoms, pruritus, dyspnea, tachycardia, and mild hypotension.According to therapeutic apheresis: a physician's handbook, with current centrifugal technology, reductions in platelet count are usually modest, and levels quickly return to baseline.In a severely thrombocytopenic patient, however, such a loss may mask the beginning of platelet recovery.Similarly, the small amount of red cells lost in the apheresis circuit may be more apparent in an anemic patient who has meager production capacity and who is receiving multiple procedures.Although generally well tolerated, the large-volume leukocytapheresis for stem cell collections in patients often results in a decline in hematocrit and platelet count, particularly because some red cells and platelets are incidentally removed with the stem cells.According to therapeutic apheresis: a physician's handbook, with current centrifugal technology, reductions in platelet count are usually modest, and levels quickly return to baseline.In a severely thrombocytopenic patient, however, such a loss may mask the beginning of platelet recovery.Similarly, the small amount of red cells lost in the apheresis circuit may be more apparent in an anemic patient who has meager production capacity and who is receiving multiple procedures.Although generally well tolerated, the large-volume leukocytapheresis for stem cell collections in patients often results in a decline in hematocrit and platelet count, particularly because some red cells and platelets are incidentally removed with the stem cells.Investigation is in process and a follow-up report will be provided.Citation: benakli, et al malek benakli*, redhouane ahmed nacer, farih mehdid, rachida belhadj, nadia rahmoune, mounira baazizi, dina ait ouali, farida harieche, rose-marie hamladji.
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Per journal article "peripheral blood stem cell mobilization and collection in pediatric healthy sibling donors weighing 20 kilograms or less; algerian experience" by benakli, et al peripheral blood stem cells (pbsc) are the source of allogeneic hematopoietic stem cell transplants currently used for malignant and non-malignant hematological diseases.Pbsc harvest may be difficult in young children who are donors.Extracorporeal separator line priming by red blood cells or albumin alone is usually required to improve haemodynamic tolerance and efficacy of collection.We present our experience with 29 children weighing 20 kg or less mobilised between january 2005 and june 2018.The median age and weight at the time of apheresis were 5 years and 18 kg, respectively.A total of 54 pbsc were performed.The median cell yield per apheresis was 5.9 × 106 cd34+cells/kg (2,5-13,9) recipient body weight (rbw).Despite their low weight, insertion of a femoral catheter was avoided in 58.6% of children.Nineteen donors required 2 or 3 apheresis sessions without any major complication.Twenty-nine pts with hemopathies have successfully benefited from pbsc except one case of rejection with aplastic anemia.Morbidity related to pbsc collections was low.Transient hypotension during the procedure required intravenous fluids in 3 cases (10,3%).Ten children (34,4%) developed symptomatic hypocalcemia corrected by calcium injection." section 3.2 (complications related to apheresis), page 3 there were 6 instances reported for intravenous diazepam, 3 instances of vasovagal rxn for transient hypotension, and 10 instances of citrate rxn for calcium injection.Specific details, such as patient information and outcome, were not included in the article for these events, therefore this report is being provided as a summary of the events.The collection set is not available for return because it was discarded by the customer.
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