Identification of the molecular etiology in rare congenital hemolytic anemias using next-generation sequencing with exome-based copy number variant analysis.

OBJECTIVES: In congenital hemolytic anemias (CHA), it is not always possible to determine the specific diagnosis by evaluating clinical findings and conventional laboratory tests. The aim of this study is to evaluate the utility of next-generation sequencing (NGS) and clinical-exome-based copy number variant (CNV) analysis in patients with CHA. METHODS: One hundred and forty-three CHA cases from 115 unrelated families referred for molecular analysis were enrolled in the study. Molecular analysis was performed using two different clinical exome panels in 130 patients, and whole-exome sequencing in nine patients. Exome-based CNV calling was incorporated into the traditional single-nucleotide variant and small insertion/deletion analysis pipeline for NGS data in 92 cases. In four patients from the same family, the PK Gypsy variant was investigated using long-range polymerase chain reaction. RESULTS: Molecular diagnosis was established in 86% of the study group. The most frequently mutated genes were SPTB (31.7%) and PKLR (28.5%). CNV analysis of 92 cases revealed that three patients had different sizes of large deletions in the SPTB and six patients had a deletion in the PKLR. CONCLUSIONS: In this study, NGS provided a high molecular diagnostic rate in cases with rare CHA. Analysis of the CNVs contributed to the diagnostic success.

The effect of virtual reality on pain, fear and emotional appearance during blood draw in pediatric patients at the hematology-oncology outpatient clinic: A randomized controlled study.

OBJECTIVE: Invasive attempts can be very painful and stressful for pediatric patients. Virtual Reality (VR) can be used to distract patients undergoing such procedures in pediatric hematology oncology patients. METHODS: A parallel trial design approach was adopted for this randomized controlled trial, guided by the CONSORT checklist. The study sample (n = 69) was divided into a VR group (n = 34) and a control group (n = 35) using stratified randomization. For the blood draw attempt, no distraction method was applied to the control group, while the children in the VR group were distracted from the procedure with the Epic Roller Coasters VR application. The primary variable assessed was pain, while secondary variables were fear and emotional appearance. The scores of emotional appearance, fear, and pain were compared with a Mann-Whitney U Test. RESULTS: The pre-procedure emotional appearance score was 11.3 ± 4.3 in the VR group and 11.0 ± 5.0 in the control group, and the post-procedure score was 6.5 ± 3.3 in the VR group and 11.8 ± 5.3 in the control group, indicating a difference in emotional appearance after the procedure. VR group had lower negative emotional appearance, lower pain, and lower fear scores after procedure compared to the control group. CONCLUSION: VR can be considered an effective approach to reducing the negative emotional appearance and for relieving pain and fear in children aged 4-12 years undergoing blood draw procedures in pediatric hematology and oncology outpatient unit (ClinicalTrials.gov: NCT05675358).

Can Propranolol Affect Platelet Indices in Infantile Hemangioma?

INTRODUCTION: Propranolol, a nonselective beta-blocker used in the medical treatment of infantile Hemangioma (IH), has been shown to decrease the levels of vascular endothelial growth factor and reduce angiogenesis with its antiproliferative and antiangiogenetic effects. MATERIALS AND METHODS: It has been reported that the storage, transport, and secretion of vascular endothelial growth factor (VEGF) are associated with platelet volume indices (PVI). We aimed to investigate the effect of propranolol on PVI in IH patients. Propranolol treatment was started on 22 IH patients. Platelets, mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit values in the follow-ups at months 0, 1, and 2 were compared between 22 patients who received treatment and 25 patients who did not. RESULTS: While a statistically significant difference between months 0, 1, and 2 in PDW and MPV values was detected in the treated group, it was not detected in the untreated group. Taking into consideration that VEGF levels were higher at the beginning of the treatment in the pathophysiology of the disease, it was thought that the decrease in VEGF levels by propranolol may have led to a decrease in MPV and PDW levels in the treatment group. CONCLUSION: Consequently, in IH cases, propranolol response follow-up can be evaluated with PVIs, especially MPV and PDW, and it may facilitate clinicians' monitoring of the disease after propranolol administration.

Central nervous system thrombosis in pediatric acute lymphoblastic leukemia in Turkey: A multicenter study.

BACKGROUND: In patients with acute lymphoblastic leukemia (ALL), the risk of thromboembolism increases due to hemostatic changes secondary to the primary disease and due to treatment-related factors. In this multicenter study, we aimed to research the frequency of central nervous system (CNS) thrombosis occurring during treatment, hereditary and acquired risk factors, clinical and laboratory features of patients with thrombosis, treatment approaches, and thrombosis-related mortality and morbidity rates in pediatric ALL patients. PROCEDURE: Pediatric patients who developed CNS thrombosis during ALL treatment from 2010 to 2021 were analyzed retrospectively in 25 different Pediatric Hematology Oncology centers in Türkiye. The demographic characteristics of the patients, symptoms associated with thrombosis, the stage of the leukemia treatment during thrombosis, the anticoagulant therapy applied for thrombosis, and the final status of the patients recorded through electronic medical records were determined. RESULTS: Data from 70 patients with CNS thrombosis during treatment, out of 3968 pediatric patients with ALL, were reviewed. The incidence of CNS thrombosis was 1.8% (venous: 1.5 %; arterial: 0.03%). Among patients with CNS thrombosis, 47 had the event in the first 2 months. Low molecular weight heparin (LMWH) was the most commonly used treatment with a median of 6 months (min-max: 3-28 months). No treatment-related complications occurred. Chronic thrombosis findings occurred in four patients (6%). In five (7%) patients who developed cerebral vein thrombosis, neurological sequelae (epilepsy and neurological deficit) remained. One patient died related to thrombosis, and the mortality rate was 1.4%. CONCLUSION: Cerebral venous thrombosis and, less frequently, cerebral arterial thrombosis may develop in patients with ALL. The incidence of CNS thrombosis is higher during induction therapy than during other courses of treatment. Therefore, patients receiving induction therapy should be monitored carefully for clinical findings suggestive of CNS thrombosis.

Evaluation of coagulation parameters and impact of transfusion on coagulation in patients with beta thalassemia major.

There have been several studies that have shown that patients with beta thalassemia major are at a higher risk of thrombosis due to the procoagulant activity of thalassemic erythrocytes, decreased liver synthetic function, increased platelet activity and vascular endothelial activation attributed to chronic oxidative stress, although there are no established tests to predict thrombotic risk in TM patients. In this study, we evaluated whether or not the platelet function analyser (PFA-200) and thrombin generation test (TGT) would be useful tools to identify hypercoagulability and risk of thrombosis in thalassemia major patients. The study included 50 patients with thalassemia major and 104 healthy control group. Pretransfusion and posttransfusion PFA-200 and TGT results were compared with control group. We found that median C/ADP and C/EPI values in the thalassemia major group were greater in both the pre and posttransfusion samples than the C/ADP and C/EPI results from the control group. The TGT results showed there was no difference between control group and the results from the thalassemia major group. The TGT and PFA-200 testing did not identify hypercoagulability nor identify clear testing parameters to predict a thalassemia major patient's risk of thrombosis. There may be other mechanisms/causes yet unidentified that could better explain thalassemia major patient's increased risk from thromboembolic events.

[The Role of Anti-HBc Testing on Donor Selection and Its Contribution to Current Alghorithms; Can the Gülhane Experience Be a Model for Turkey?] / Anti-HBc Testinin Bagisçi Seçimindeki Rolü, Güncel Algoritmaya Katkisi; Gülhane Deneyimi Türkiye için Örnek Model Olur Mu?

Additional or different test procedures can be applied to maximize transfusion safety by reducing the risk of transfusion-transmitted infections. Antibodies to hepatitis B core antigen (anti-HBc) is one of the most commonly used serologic marker in this context. The aim of the study was to analyse anti-Hbc test results performed within the scope of routine screening tests in our center and to examine the effect of the donor re-entry protocol established. A total of 57191 people who applied to Gülhane Regional Blood Center to donate blood between 2014-2019 were included in the study. All blood donations were screened for anti-HBc by chemiluminescense immunoassay (Architect i2000 SR, AXSYM, Abbott, IL, USA). Hepatitis B surface antibody (anti-HBs) and hepatitis B virus (HBV) deoxyribonucleic acid (DNA) (ABI Prism 7500 Real time PCR system, Applied Biosystems, USA) tests were performed in accordance with the donor recovery protocol for those who could be reached among those with positive for anti-HBc test results. Samples with > 100 IU/ml of anti-HBs levels and negative for HBV DNA test were included in the donor pool. Of the 57 191 blood donors involved in the study, 5125 (8.5%) were found as positive for anti-HBc. Of the donors, 54 035 (94.4%) were male and 3156 (5.5%) were female. The difference was found to be statistically significant in terms of gender distribution between the years of the study (p<0.001). The highest anti-HBc positivity rate (35.7%) was in the age group of 60 years and over while the lowest positivity rate (3.8%) was in the age group of 18-30 years (r= 0.549, p= 0.0001). The year with the highest anti-HBc seroprevalance (10.1%) was 2017, while the year with the lowest (7.9%) was 2014. The distribution of seropositivity over the years was statistically significant (p<0.001). In the study, anti-HBs and HBV-DNA test results of 439 donors were accessible and of which 301 (68.5%) were considered eligible to donate again according to the re-entry protocol. The isolated anti-HBc positivity and HBV-DNA positivity rates were 7.5% (33/430) and 0.2% (1/439) respectively,in blood donors to whom re-entry protocol was performed. The seroprevalance of anti-HBc below 10% during the six-year period in which the study was conducted is a critical data for the evaluation of this test within the scope of routine microbiological screening tests. Moreover, we have observed that donor losses due to the antiHBc testing can be significantly reduced with the implementation of donor re-entry protocols. Anti-HBc screening strategy should be decided by considering of HBV epidemiology, cost-effectivity and possible blood donor losses.

Thrombin generation in children with febrile neutropenia.

BACKGROUND: Febrile neutropenia (FN) is a common and serious complication in patients with leukemia. Hemostasis and inflammation are two interrelated systems in response to infection. We aimed to investigate the course of thrombin formation in febrile neutropenia attack of children with acute lymphoblastic leukemia (ALL). METHODS: Thrombin generation was monitored in children treated for ALL at diagnosis of febrile neutropenia (FN) (t < sub > 0 < /sub > ), at 48 < sup > th < /sup > hour of FN (t1) and after recovery from neutropenia (t < sub > 2 < /sub > ). RESULTS: Twenty-nine patients and 50 healthy children as control were enrolled into the study. Mean endogenous thrombin potential (ETP) and mean peak value of thrombin results at t < sub > 1 < /sub > were significantly higher than at t < sub > 0 < /sub > , t < sub > 2 < /sub > and control groups, respectively. A positive but statistically nonsignificant correlation between ETP values at t < sub > 1 < /sub > and duration of neutropenia was observed. CONCLUSION: Although thrombin generation is enhanced both due to chemotherapy or malignancy itself, our results revealed that thrombin formation also increased in neutropenic infection of children with leukemia.

A case of pediatric psoriasis achieving remission after allogenic bone marrow transplantation.

BACKGROUND: Psoriasis is an inflammatory skin disease in which the cells and molecules of innate and adaptive immunity are involved in the pathogenesis. Aplastic anemia is a bone marrow deficiency syndrome that is characterized by an extreme reduction in the number of blood cells as a result of failure in hematopoiesis. Allogenic hematopoietic stem cell transplantation is a promising treatment for Aplastic Anemia and it is important to note that other comorbid diseases like psoriasis- since both have some common pathogenetic mechanisims- might achieve remission after treatment. CASE: We present a 12-years-old male patient who underwent bone marrow transplantation for aplastic anemia and his psoriasis vulgaris lesions completely regressed. The final follow-up visit on day 150 also revealed no sign of the pre-transplantation skin and scalp lesions. CONCLUSIONS: This is the first case of pediatric psoriasis together with aplastic anemia that achieved complete remission of psoriasis after bone marrow transplantation. Our case report needs to be supported by prospective studies involving larger patient populations.

Evaluating the effect of donor anxiety levels and lifestyle characteristics on the activation of platelet concentrates.

BACKGROUND: Smoking, alcohol use, performing regular physical exercise, dietary habits, and anxiety level may cause platelet activation. We aimed to evaluate the anxiety levels, smoking status, alcohol intake, and sportive habits of donors, and determine their impact on the quality of apheresis-platelets. METHODS: State and Transient Anxiety Inventory (STAI) was used to determine the level of donors' anxiety. STAI has two subscales: S-anxiety scale (STAI-I) and T-anxiety scale (STAI-II), each comprising 20 questions rated on a 4-point Likert scale. Data on smoking, alcohol consumption, and performing regular physical exercise were obtained from a questionnaire filled out before donation. Flow cytometric analysis was used to quantify activated platelets. RESULTS: The STAI-I level of 86 participants was normal, while that of 12 was higher. No significant difference was found in the active platelet absolute count [1.8×1011 (2.7) and 1.4×1011 (1.3), respectively; P=0.665] between donors with normal STAI-I levels and those with higher STAI-I levels. Of 98 donors, 42 had normal STAI-II levels, while 56 had higher STAI-II levels. No significant difference was found in the active platelet absolute count [2.3×1011 (3.1) and 1.5×1011 (2.3), respectively; P=0.224] between donors with normal STAI-II levels and those with higher STAI-II levels. Platelet counts of individuals who perform regular physical exercise were significantly higher than those of individuals who did not perform regular physical exercise (6.3±1.4×1011 vs. 5.5±1.4×1011). CONCLUSION: The quality of apheresis platelets is not affected by anxiety levels and lifestyle characteristics of blood donors. There is no need to organize apheresis blood donor pool considering with these subjects.

Bringing Packed Red Blood Cells to the Point of Combat Injury: Are We There Yet?

Objective: Hemorrhage is the leading cause of injury-related prehospital mortality. We investigated worst-case scenarios and possible requirements of the Turkish military. As we plan to use blood resources during casualty transport, the impact of transport-related mechanical stress on packed red blood cells (PRBCs) was analyzed. Materials and Methods: The in vitro experiment was performed in the environmental test laboratories of ASELSAN®. Operational vibrations of potential casualty transport mediums such as Sikorsky helicopters, Kirpi® armored vehicles, and the NATO vibration standard MIL-STD-810G software program were recorded. The most powerful mechanical stress, which was created by the NATO standard, was applied to 15 units of fresh (≤7 days) and 10 units of old (>7 days) PRBCs in a blood cooler box. The vibrations were simulated with a TDS v895 Medium-Force Shaker Device. On-site blood samples were analyzed at 0, 6, and 24 h for biochemical and biomechanical analyses. Results: The mean (±standard deviation) age of fresh and old PRBCs was 4.9±2.2 and 32.8±11.8 days, respectively. Six-hour mechanical damage of fresh PRBCs was demonstrated by increased erythrocyte fragmentation rates (p=0.015), hemolysis rates (p=0.003), and supernatant potassium levels (p=0.003) and decreased hematocrit levels (p=0.015). Old PRBC hemolysis rates (p=0.015), supernatant potassium levels (p=0.015), and supernatant hemoglobin (p=0.015) were increased and hematocrit levels were decreased (p=0.015) within 6 h. Two (13%) units of fresh PRBCs and none of the old PRBCs were eligible for transfusion after 6 h of mechanical stress. Conclusion: When an austere combat environment was simulated for 24 h, fresh and old PRBC hemolysis rates were above the quality criteria. Currently, the technology to overcome this mechanical damage does not seem to exist. In light of the above data, a new national project is being performed.

Elevated plasma asymmetric dimethylarginine levels in children with beta-thalassemia major may be an early marker for endothelial dysfunction.

OBJECTIVES: Beta-thalassemia major is associated with the increased risk of cardiovascular morbidity and mortality. Asymmetric dimethylarginine (ADMA) has been implicated in the pathogenesis of endothelial dysfunction and atherosclerosis. In this study, we aimed to investigate circulating ADMA concentrations in children with beta-thalassemia major. METHODS: Thirty-one beta-thalassemia major children aged between 4 and 16 year old and age, gender-matched 36 healthy controls were enrolled in the study. Plasma ADMA was measured along with the soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1), P-selectin, and Pentraxin-3. RESULTS: Age, gender and body mass index were similar in two groups. Plasma ADMA, sVCAM-1, and sICAM-1 measurements were significantly higher in beta-thalassemia major patients than the control group (p < 0.004 for ICAM-1, p < 0.001 for other parameters). There were positive significant correlations between ADMA, sVCAM-1 and sICAM-1 (r = 0.437, p < 0.001; r = 0.544, p < 0.001; r = 0.405, p < 0.001, respectively) in the whole group. DISCUSSION: The findings of the current study show us that increased plasma ADMA levels in children with beta-thalassemia major may be an early marker for endothelial dysfunction and may play a role in the development of premature atherosclerosis in beta-thalassemia major patients.

Heavy metal levels in patients with ineffective erythropoiesis.

OBJECTIVES: Iron is taken into enterocytes at the duodenum via apical divalent metal-ion transporter 1 protein. Besides iron, divalent metal-ion transporter 1 also transports other divalent metals. We aimed to investigate blood heavy metal levels in patients with ineffective erythropoiesis. METHODS: Blood levels of heavy metals including Pb, Al, Cd, Cr, Co, Cu, and Zn were measured in patients with thalassemia major (TM), thalassemia intermedia (TI), congenital dyserythropoietic anemia (CDA), and age- and sex-matched healthy controls. RESULTS: Blood samples were obtained from 68 patients (51 patients with TM, 8 with TI, 9 with CDA), and a control group that included 65 volunteers. Patients with TM were found to have lower Al, Pb, and Zn, and higher Cd levels compared with the control group. The patients treated with deferasirox were further analyzed and Pb and Zn levels were found lower compared with the control group. DISCUSSION: Patients with TM had tendency to have elevated levels of plasma cadmium; however, the median level was not at a toxic level. Increased metal-ion transporter 1 activity may cause heavy metal accumulation, but deferasirox chelation may be protective against heavy metals besides iron.

Relation of insulin resistance to neurocognitive function and electroencephalography in obese children.

BACKGROUND: Childhood obesity may lead to neuronal impairment in both the peripheral and the central nervous system. This study aimed to investigate the impact of obesity and insulin resistance (IR) on the central nervous system and neurocognitive functions in children. METHODS: Seventy-three obese children (38 male and 35 female) and 42 healthy children (21 male and 21 female) were recruited. Standard biochemical indices and IR were evaluated. The Wechsler Intelligence Scale for Children-Revised (WISC-R) and electroencephalography (EEG) were administered to all participants. The obese participants were divided into two groups based on the presence or absence of IR, and the data were compared between the subgroups. RESULTS: Only verbal scores on the WISC-R in the IR+ group were significantly lower than those of the control and IR- groups. There were no differences between the groups with respect to other parameters of the WISC-R or the EEG. Verbal scores of the WISC-R were negatively correlated with obesity duration and homeostatic model assessment-insulin resistance (HOMA-IR) values. EEGs showed significantly more frequent 'slowing during hyperventilation' (SDHs) in obese children than non-obese children. CONCLUSIONS: Neurocognitive functions, particularly verbal abilities, were impaired in obese children with IR. An early examination of cognitive functions may help identify and correct such abnormalities in obese children.

Bleeding risk of surgery and its prevention in patients with inherited platelet disorders.

Excessive bleeding at surgery is a feared complication in patients with inherited platelet disorders. However, very few studies have evaluated the frequency of surgical bleeding in these hemorrhagic disorders. We performed a worldwide, multicentric, retrospective study to assess the bleeding complications of surgery, the preventive and therapeutic approaches adopted, and their efficacy in patients with inherited platelet disorders: the Surgery in Platelet disorders And Therapeutic Approach (SPATA) study. We rated the outcome of 829 surgical procedures carried out in 423 patients with well-defined forms of inherited platelet disorders: 238 inherited platelet function disorders and 185 inherited platelet number disorders. Frequency of surgical bleeding was high in patients with inherited platelet disorders (19.7%), with a significantly higher bleeding incidence in inherited platelet function disorders (24.8%) than in inherited platelet number disorders (13.4%). The frequency of bleeding varied according to the type of inherited platelet disorder, with biallelic Bernard Soulier syndrome having the highest occurrence (44.4%). Frequency of bleeding was predicted by a pre-operative World Health Organization bleeding score of 2 or higher. Some types of surgery were associated with a higher bleeding incidence, like cardiovascular and urological surgery. The use of pre-operative pro-hemostatic treatments was associated with a lower bleeding frequency in patients with inherited platelet function disorders but not in inherited platelet number disorders. Desmopressin, alone or with antifibrinolytic agents, was the preventive treatment associated with the lowest bleedings. Platelet transfusions were used more frequently in patients at higher bleeding risk. Surgical bleeding risk in inherited platelet disorders is substantial, especially in inherited platelet function disorders, and bleeding history, type of disorder, type of surgery and female sex are associated with higher bleeding frequency. Prophylactic pre-operative pro-hemostatic treatments appear to be required and are associated with a lower bleeding incidence.

Hematopoietic Stem Cell Transplantation Using Preimplantation Genetic Diagnosis and Human Leukocyte Antigen Typing for Human Leukocyte Antigen-Matched Sibling Donor: A Turkish Multicenter Study.

Preimplantation genetic diagnosis involves the diagnosis of a genetic disorder in embryos obtained through in vitro fertilization, selection of healthy embryos, and transfer of the embryos to the mother's uterus. Preimplantation genetic diagnosis has been used not only to avoid the risk of having an affected child, but it also offers, using HLA matching, preselection of potential HLA-genoidentical healthy donor progeny for an affected sibling who requires bone marrow transplantation. Here, we share the hematopoietic stem cell transplantation results of 52 patients with different benign and malign hematological or metabolic diseases or immunodeficiencies whose donors were siblings born with this technique in Turkey since 2008. The median age of the patients' at the time of the transplantation was 8 years (range, 3 to 16 years) and the median age of the donors was 2 years (range, .5 to 6 years). The most common indication for HSCT was thalassemia major (42 of all patients, 80%). The stem cell source in all of the transplantations was bone marrow. In 37 of the transplantations, umbilical cord blood of the same donor was also used. In 50 of the 52 patients, full engraftment was achieved with a mean of 4.6 × 106 CD 34+ cells per kg of recipient weight. Ninety-six percent of the patients have been cured through hematopoietic stem cell transplantation without any complication. Primary engraftment failure was seen in only 2 patients with thalassemia major. All of the donors and the patients are alive with good health status. Preimplantation genetic diagnosis with HLA matching offers a life-saving chance for patients who need transplantation but lack an HLA genoidentical donor.

Generation of Platelet Microparticles after Cryopreservation of Apheresis Platelet Concentrates Contributes to Hemostatic Activity.

OBJECTIVE: In the last decade, substantial evidence has accumulated about the use of cryopreserved platelet concentrates, especially in trauma. However, little reference has been made in these studies to the morphological and functional changes of platelets. Recently platelets have been shown to be activated by cryopreservation processes and to undergo procoagulant membrane changes resulting in the generation of platelet-derived microparticles (PMPs), platelet degranulation, and release of platelet-derived growth factors (PDGFs). We assessed the viabilities and the PMP and PDGF levels of cryopreserved platelets, and their relation with thrombin generation. MATERIALS AND METHODS: Apheresis platelet concentrates (APCs) from 20 donors were stored for 1 day and cryopreserved with 6% dimethyl sulfoxide. Cryopreserved APCs were kept at -80 °C for 1 day. Thawed APCs (100 mL) were diluted with 20 mL of autologous plasma and specimens were analyzed for viabilities and PMPs by flow cytometry, for thrombin generation by calibrated automated thrombogram, and for PDGFs by enzyme-linked immunosorbent assay testing. RESULTS: The mean PMP and PDGF levels in freeze-thawed APCs were significantly higher (2763±399.4/µL vs. 319.9±80.5/µL, p<0.001 and 550.9±73.6 pg/mL vs. 96.5±49 pg/mL, p<0.001, respectively), but the viability rates were significantly lower (68.2±13.7% vs. 94±7.5%, p<.001) than those of fresh APCs. The mean endogenous thrombin potential (ETP) of freeze-thawed APCs was significantly higher than that of the fresh APCs (3406.1±430.4 nM.min vs. 2757.6±485.7 nM.min, p<0.001). Moreover, there was a significant positive poor correlation between ETP levels and PMP levels (r=0.192, p=0.014). CONCLUSION: Our results showed that, after cryopreservation, while levels of PMPs were increasing, significantly higher and earlier thrombin formation was occurring in the samples analyzed despite the significant decrease in viability. Considering the damage caused by the freezing process and the scarcity of evidence for their in vivo superiority, frozen platelets should be considered for use in austere environments, reserving fresh platelets for prophylactic use in blood banks.

Is one-size-fits-all strategy adequate for platelet storage?

BACKGROUND: Platelet suspensions (PSs) are stored at room temperature. However, recent reports show that PSs stored at 4 °C possess superior hemostatic properties. We compared the viabilities and thrombin generation capacities of PSs stored either at 4 °C or 22 °C hours. MATERIALS AND METHODS: Twenty units of apheresis derived platelets (ADPs) from 20 male donors and 20 units of random platelet suspensions (RPSs) from another 20 male donors were obtained. Half of the ADPs and half of the RPSs (10 units/per group) were stored at 4 °C, the other halves of ADPs and RPSs (10 units/per group) were stored in agitators at 22 °C for 48 hours. The flow cytometric viability tests and thrombin generation tests of the PSs were assessed. RESULTS: The viabilities of both ADPs and RPSs group platelets, stored either at 4 °C or 22 °C for 48 hours, were not statistically significantly different. The ADPs and RPSs stored at 4 °C generated significantly higher peak thrombin levels than the platelets stored at 22 °C. Moreover, the ADPs group stored at 4 °C showed significantly shorter time to thrombin generation and reach peak levels. CONCLUSION: The PSs stored at 4 °C showed higher and faster thrombin generation capacities than the room temperature PSs. Given the superior hemostatic properties of refrigerated platelets, creating different storage temperature capabilities for specific transfusion purposes may be a prudent approach, especially for improving the outcome of bleeding trauma casualties.

Association of nerve conduction impairment and insulin resistance in children with obesity.

AIM: The objective of our study was to investigate nerve conduction in normoglycemic obese children. METHODS: A total of 60 children with obesity (30 female and 30 male) and 30 healthy children (15 female and 15 male) were enrolled in the study. Insulin resistance (IR) and other metabolic disturbances were investigated and nerve conduction was measured in all participants. Obese children were divided into groups according to the presence of IR. All results were compared between these subgroups. RESULTS: The nerve conduction velocity (NCV) of motor median nerves in the IR+ group was significantly higher than that in the IR- group and lower than that in the control group. The NCV of the motor peroneal nerve in the IR+ group was significantly lower than that in the IR- group. The sensory nerve action potential (SNAP) of the sensory median nerve was significantly lower in the IR+ group compared to that in the IR- group. The sensory sural nerve's SNAP was significantly lower in the IR+ group than that in the control group. CONCLUSION: Nerve conduction tests may help to detect early pathologies in peripheral nerves and to decrease morbidities in obese children.

Freezing of Apheresis Platelet Concentrates in 6% Dimethyl Sulfoxide: The First Preliminary Study in Turkey.

OBJECTIVE: Transfusion of platelet suspensions is an essential part of patient care for certain clinical indications. In this pioneering study in Turkey, we aimed to assess the in vitro hemostatic functions of platelets after cryopreservation. MATERIALS AND METHODS: Seven units of platelet concentrates were obtained by apheresis. Each apheresis platelet concentrate (APC) was divided into 2 equal volumes and frozen with 6% dimethyl sulfoxide (DMSO). The 14 frozen units of APCs were kept at -80 °C for 1 day. APCs were thawed at 37 °C and diluted either with autologous plasma or 0.9% NaCl. The volume and residual numbers of leukocytes and platelets were tested in both before-freezing and post-thawing periods. Aggregation and thrombin generation tests were used to analyze the in vitro hemostatic functions of platelets. Flow-cytometric analysis was used to assess the presence of frozen treated platelets and their viability. RESULTS: The residual number of leukocytes in both dilution groups was <1x106. The mean platelet recovery rate in the plasma-diluted group (88.1±9.5%) was higher than that in the 0.9% NaCl-diluted group (63±10%). These results were compatible with the European Directorate for the Quality of Medicines quality criteria. Expectedly, there was no aggregation response to platelet aggregation test. The mean thrombin generation potential of post-thaw APCs was higher in the plasma-diluted group (2411 nmol/L per minute) when compared to both the 0.9% NaCl-diluted group (1913 nmol/L per minute) and the before-freezing period (1681 nmol/L per minute). The flow-cytometric analysis results for the viability of APCs after cryopreservation were 94.9% and 96.6% in the plasma and 0.9% NaCl groups, respectively. CONCLUSION: Cryopreservation of platelets with 6% DMSO and storage at -80 °C increases their shelf life from 7 days to 2 years. Besides the increase in hemostatic functions of platelets, the cryopreservation process also does not affect their viability rates.

In vitro efficacy of frozen erythrocytes: implementation of new strategic blood stores to alleviate resource shortage (issue revisited).

BACKGROUND/AIM: Currently, the provision of blood products largely depends on walking blood banks and limited amounts of stored blood with short shelf lives. We aimed to compare the efficacy of erythrocyte concentrate (ECs) by pre- and postfreezing in vitro tests. MATERIALS AND METHODS: In our study, 10 ECs were glycerolized, frozen, thawed, and then deglycerolized using the Naval Blood Research Laboratory method. In addition to using the standard tests, ATP and 2,3-DPG levels and the viability of erythrocytes were also determined. RESULTS: The prefreezing mean viability rates of erythrocytes changed from 89.7 ± 13.7% to 98.6 ± 1.8% after thawing and deglycerolization. Prefreezing and day 0 ATP levels (1.64 ± 0.15 µmol/g Hb and 1.81 ± 0.14 µmol/g Hb, respectively) were similar. The 2,3-DPG levels decreased from 18.09 ± 4.78 µmol/g Hb measured before the procedure to 10.41 ± 4.58 µmol/g Hb on day 0. The mean hemolysis rates and supernatant Hb levels changed from 0.21 ± 0.11% to 0.36 ± 0.12% and 1 ± 0.5 g/L to 1.5 ± 0.5 g/L, respectively. CONCLUSION: The test results showed the efficacy of the frozen-thawed ECs to be used in humans for a broad spectrum of clinical indications. As a part of a contingency plan, national frozen blood reserves need to be established.