Diagnostic Value of the Pediatric Bleeding Questionnaire in Prediction of Bleeding in Minor Surgery.

OBJECTIVE: Preoperative coagulation tests have not been shown to be effective in predicting bleeding complications. The Pediatric Bleeding Questionnaire (PBQ) is a proven and sensitive tool for diagnosing children with a predisposition to bleeding. The aim of this study was to evaluate the usefulness of PBQ as a preoperative screening tool for the prediction of bleeding after minor surgical interventions. METHODS: Preoperative coagulation tests and PBQ were performed in all patients who underwent minor surgery. The postoperative bleeding status was evaluated and then compared with the coagulation tests and PBQ of the patients. RESULTS: Evaluation was made of a total of 706 patients, comprising 91.2% males and 8.8% females, with a mean age of 4.8 years (median: 4 y, QR: 1 to 7 y). Prolongation in coagulation tests was observed in 131 (18.5%) patients. Repeated tests in 116 patients were within the normal range, and 5 patients received treatment. Postoperative bleeding occurred in 4 (0.5%) patients. The relationship between coagulation tests and postoperative bleeding was not significant. PBQ was found to be ≥2 in 14 patients, but none of these patients had postoperative bleeding. No significant relationship was found between postoperative bleeding status and PBQ (p:0.77). The sensitivity, specificity, positive predictive, and negative predictive values of PBQ were 0%, 98%, 0%, and 97.4%, respectively. CONCLUSIONS: The results of this study demonstrated that neither coagulation tests nor PBQ will be sufficient to predict bleeding after minor surgery, that prolongation in coagulation tests does not always indicate a bleeding tendency, and that bleeding history should also be recorded in detail.

Sirolimus is effective and safe in childhood relapsed-refractory autoimmune cytopenias: A multicentre study.

Autoimmune cytopenias are a heterogeneous group of disorders characterized by immune-mediated destruction of haematopoietic cell lines. Effective and well-tolerated treatment options for relapsed-refractory immune cytopenias are limited. In this study, the aim was to evaluate the efficacy and safety of sirolimus in this disease group within the paediatric age group. The study enrolled patients in the paediatric age group who used sirolimus with a diagnosis of immune cytopenia between December 2010 and December 2020, followed at six centres in Turkey. Of the 17 patients, five (29.4%) were treated for autoimmune haemolytic anaemia (AIHA), six (35.2%) for immune thrombocytopenic purpura (ITP) and six (35.2%) for Evans syndrome (ES). The mean response time was 2.7 months (range, 0-9 months). Complete response (CR) and partial response (PR) were obtained in 13 of 17 patients (76.4%) and nonresponse (NR) in four patients (23.5%). Among the 13 patients who achieved CR, three of them were NR in the follow-up and two of them had remission with low-dose steroid and sirolimus. Thus, overall response rate (ORR) was achieved in 12 of 17 patients (70.5%). In conclusion, sirolimus may be an effective and safe option in paediatric patients with relapsed-refractory immune cytopenia.

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.

A hidden burden of disease in a specific group: Evaluation of COVID-19 seroconversion rates in pediatric patients with leukemia.

BACKGROUND: SARS-CoV-2, a respiratory viral disease, is thought to have a more severe course in patients with malignancy and low immune systems. METHODS: This prospective single-center study was conducted at the University of Health Sciences Dr Behçet Uz Children's Hospital from September 22 to December 31, 2021. Asymptomatic COVID-19 transmission rates were assessed using SARS-CoV-2 serology in patients with leukemia who had no history of COVID-19 infection. RESULTS: Among the 54 patients, 19 (35.2%) were females and 35 (64.8%) were males. The median age was 5.5 years (min 6 months, max 17 years). Forty-nine (90.5%) of the leukemia patients had acute lymphoblastic leukemia, while 5 (9.5%) had acute myeloid leukemia. Five of the 54 patients had a history of COVID-19 or contact with a positive person. SARS-CoV-2 IgG positivity was detected in 18 (36.7%) of 49 patients with no history of COVID-19 infection. DISCUSSION: Leukemia patients have a high seroconversion for SARS-CoV-2 without showing any symptoms supporting the asymptomatic course of COVID-19 infection in this risk group. CONCLUSION: As a result, patients with leukemia may have a high rate of COVID-19 seroconversion without showing symptoms.

The evaluation of Candida-related central line-related bloodstream infections in pediatric cancer patients: A pre- and post-intervention study.

Aim/Objections: The purpose of this study was to assess the efficacy of a central line maintenance bundle in preventing catheter-related (implanted venous access devices, port) Candida bloodstream infections. Methods: The study encompassed two distinct time periods, namely, pre-bundle and bundle. The number of catheter-related bloodstream infections (CRBSI) episodes per catheter days for each timeframe was determined. Findings/Results: Upon implementation of the central line bundle, the rate of CRBSI reduced significantly from 4.27 per 1000 central line days in the pre-bundle period to 1.0 per 1000 central line days in the bundle period (p < .001). Discussion: Using a central line bundle to avoid CRBSIs in pediatric cancer patients with ports led to a significant decrease in Candida species-related CRBSIs.

Successful Treatment of a Child with Hemoglobin Hammersmith with Hematopoietic Stem Cell Transplantation.

Hemoglobin (Hb) Hammersmith, formed by serine substitution for phenylalanine at residue 42 in the beta-globin chain, is a very rare variant of unstable hemoglobin with low oxygen affinity. For patients with hemoglobinopathies, it is well-established that hematopoietic stem cell transplantation provides a complete cure, but the literature on its role for those with Hb Hammersmith is limited. A seven-month-old girl who was examined for anemia and splenomegaly was followed up for congenital hemolytic anemia. The patient with visible cyanosis of the lips and whose p50 was low in blood gas was diagnosed with Hb Hammersmith through the DNA sequence analysis. During the follow-up, frequent blood transfusions had to be given due to anemia aggravated by infections. Following a successful hematopoietic stem cell transplant from an HLA-matched sibling, the patient completely recovered from Hb Hammersmith. The case is presented because of its rarity.

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.

Hematopoietic stem cell transplantation with reduced toxicity conditioning regimen in mitochondrial neurogastrointestinal encephalopathy syndrome.

BACKGROUND: Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare autosomal recessive disorder due to mutations in the TYMP gene. Clinical findings are characterized by neurologic manifestations and severe gastrointestinal dysfunction. The syndrome is usually fatal, the most effective treatment appears to be hematopoietic stem cell transplantation (HSCT). PROCEDURE: In this retrospective study, we evaluated HSCT that was performed using a reduced toxicity myeloablative conditioning regimen in patients with MNGIE at our center. RESULTS: A total of six allogeneic transplant procedures were performed in four patients. Three patients had fully matched donors, and one patient had a haploidentical donor. Treosulfan-based myeloablative conditioning regimen was applied in five of six transplants. Bone marrow was used as a stem cell source. One patient is being followed up in the 4th year of posttransplant with full chimeric and without graft versus host disease (GVHD). One patient died of acute stage IV gastrointestinal system GVHD. Two patients underwent second transplantation due to engraftment failure, one of which was the patient who had a haploidentical transplant. CONCLUSIONS: Treosulfan-based regimen is well tolerated, although engraftment failure with this conditioning regimen can be a significant problem. We share our haploidentical transplant experience, which will be the first reported case in the literature.

Efficacy of Teicoplanin Lock Therapy in the Treatment of Port-related Coagulase-negative Staphylococci Bacteremia in Pediatric Oncology Patients.

The number of studies evaluating teicoplanin lock therapy in coagulase-negative staphylococcus-associated catheter infection in pediatric malignancies is limited. The aim of this study was to evaluate the efficacy of teicoplanin lock therapy in pediatric cancer cases. Twenty-two patients with coagulase-negative staphylococcus-associated totally implantable venous access device infection, who had undergone teicoplanin closure treatment, were included in the study. Demographic data, number of lock treatment days, and treatment success data were obtained from the medical files of the patients. Fourteen of the patients (63.6%) had acute lymphocytic leukemia, 3 (13.6%) had acute myelocytic leukemia, and 5 (22.7%) had solid cancer. The median neutrophil count was 240×10 3 /µL (interquartile range: 0 to 1195×10 3 /µL). Between patients with and without catheter removal, no statistically significant difference was found in terms of baseline C-reactive protein, absolute neutrophil count, and the day of starting systemic teicoplanin treatment ( P >0.05). The overall port survival rate of teicoplanin lock therapy was 72.7%. Within an average of 4 days, negative cultures of 16 (72.7%) patients whose catheters had not been removed were obtained. In conclusion, we suggest that teicoplanin lock therapy is an effective and safe treatment for catheter-related infections, caused by methicillin-resistant coagulase-negative staphylococcus.

Multiple thrombi in a child diagnosed with coronavirus disease 2019 treated with cardiac surgery.

Coronavirus disease 2019 (COVID-19) is characterized predominantly by respiratory symptoms but may affect all systems, and it has been associated with thrombosis in adults. Case series investigating the COVID-19-associated multisystem inflammatory syndrome in children have reported high fibrinogen and D-dimer levels; however, it is not known whether this causes thrombophilia. Herein, we report a previously healthy 13-year-old male patient who had multiple thromboses associated with COVID-19, which occurred during long-term follow-up and was successfully treated with cardiac surgery. We want to emphasize that the long-term effects of COVID-19 are not yet known and that the follow-up of these cases should be continued.

A Neonatal Case of Infantile Malignant Osteopetrosis Presenting with Thrombocytopenia and Hypotonicity: A Novel Mutation in Chloride Voltage-Gated Channel 7 Gene.

Autosomal recessive osteopetrosis is also known as infantile malignant osteopetrosis (IMO). The clinical course is often serious and if left untreated, it is fatal in the 1st year of life. Diagnosis is challenging and often delayed or misdiagnosed. Herein, we present an infant girl who was diagnosed with IMO during evaluations for her hypotonicity and thrombocytopenia. A novel mutation of the chloride voltage-gated channel 7 (CLCN7) gene was also reported. A 10-day-old female patient was referred to our hospital for evaluation of hypotonicity. Her physical examination was normal, other than hypotonicity. Laboratory analysis revealed thrombocytopenia and hypocalcemia. In the progress, while she was followed in outpatient clinic, hepatosplenomegaly was detected at the age of 3 months. IMO was suspected with the findings of hepatosplenomegaly, cytopenia, hypocalcemia, difficulty of obtaining bone marrow, peripheral smear findings, and hearing loss. The X-ray of the bones was consistent with IMO. A novel pathogenic homozygous c.1504>T (p.Arg502Trp) mutation in CLCN7 gene was revealed. IMO is a rare disorder and it is important to differentiate this entity for better clinical outcome. The presence of neurological and hematological findings, organomegaly, hearing loss, and vision disorders must attract attention to IMO.

Hepatitis-Associated Aplastic Anemia: Etiology, Clinical Characteristics and Outcome.

Hepatitis-associated aplastic anemia (HAA) is a form of acquired aplastic anemia (AA) in which bone marrow failure develops after an acute attack of hepatitis. Bone marrow failure leading to AA is generally severe in cases of HAA and fatal if left untreated. This retrospective multicenter study investigated clinical and laboratory characteristics, possible causes, treatment, and outcome of HAA in children. Twenty patients from 8 centers were included in the study. Aspartate aminotransferase and alanine aminotransferase were <3 to 5×upper limit of normal (ULN) in 2 patients, <5 to 10×ULN in 2 patients, and >10×ULN in 16 patients. Acute liver failure developed in 5 (29%) patients. Pancytopenia was simultaneously present in 6 of 20 (30%) patients. Eleven of the 20 patients (55%) were alive, in remission and transfusion free. Those who were alive either had undergone hematopoietic stem cell transplantation and/or immunosuppressive treatment, except 1 patient who had received no treatment. Patients with the diagnosis of acute hepatitis should be evaluated and followed up carefully for presence of cytopenia, so that definitive treatment of AA can be initiated in a timely and appropriate manner when needed.

Evaluation for Metastatic Candida Focus and Mortality at Candida-associated Catheter-related Bloodstream Infections at the Pediatric Hematology-oncology Patients.

BACKGROUND: Candidemia and Candida-associated catheter-related bloodstream infections (CRBSIs) are the significant cause of mortality and morbidity in patients with malignancy. METHODS: A retrospective analysis including all pediatric hematologic/oncologic malignancies patients with CRBSIs treated in Dr. Behçet Uz Children Diseases and Surgery Training and Research Hospital between the period of 2009 and 2020. RESULTS: During the study period, 53 children with CRBSIs associated with Candida species were included. The most common malignancy was acute lymphoblastic leukemia (45.3%) and acute myeloid leukemia (15.1%). A total of 56 Candida isolates were present including non-albicans Candida species (80.4%) and Candida albicans (19.6%). The most common isolated Candida species was Candida parapsilosis (42.9%) and followed by C. albicans (19.6%). The ratio of azole prophylaxis was significantly higher in patients with the non-albicans Candida group (P=0.031). Candida-related endocarditis (vegetation) was present in 2 (3.8%) patients, and the overall rate of hepatosplenic candidiasis was 3.8%. Seven days Candida attributable mortality was 7.5% (4 patients) and 30 days Candida attributable mortality was 11.3% (6 patients). The Candida species responsible for the Candida-related deaths were as following: Candida tropicalis (n=3), C. parapsilosis (n=2), and C. lusitanae (n=1). CONCLUSION: In pediatric cancer patients with Candida-associated CRBSIs, evaluation of the patient for organ involvement including liver and spleen ultrasonography and cardiac involvement with echocardiography are essential regardless of the patients' clinical picture.

Assessment of clinical characteristics and treatment outcomes of pediatric patients with intracardiac thrombosis: a single-center experience.

The prevalence of intracardiac thrombus (ICT) is gradually increasing, though it is rare among children. Data related to the occurrence of ICT among children are limited, and treatment recommendations have been made utilizing adult guidelines. The primary objective of this study is to determine associated factors, management, and outcomes of intracardiac thrombosis in children. Between January 2013 and January 2020, patients diagnosed with ICT at the Pediatric Hematology-Oncology and Pediatric Cardiology departments in our hospital were included in the study. Demographic characteristics, clinical and laboratory findings, treatment protocols, and outcomes were analyzed retrospectively. The median age at diagnosis was 10.5 months (2 days to 14.5 years), and the median follow-up period was 6.5 months (1 month to 3.1 years). The most common primary diagnoses of the patients, in order of frequency, were heart disease (n: 8), metabolic disease (n: 3), prematurity and RDS (n: 3), burns (n: 2), pneumonia (n: 2), and asphyxia (n: 2). CVC was present in 19/23 of the patients. The reasons for CVC insertion were the need for plasmapheresis in one patient with a diagnosis of HUS and the need for well tolerated vascular access because of long-term hospitalization in others. LMWH was administered to all patients as first-line therapy. Complete response was achieved in 19 (79%) of 24 patients and 4 patients (16.6%) were unresponsive to medical treatment. It was found out that the thrombus location, type, sepsis, and hemoculture positivity, as well as the presence of CVC, had no impact on treatment response (chi-square P = 0.16, 0.12, 0.3, 0.49, 0.56). Moreover, no correlation was determined between thrombus size and treatment response (Mann Whitney U test P = 0.47). The mortality rate was determined to be 12.5% (3/24). Spontaneous occurrence of ICT is rare in childhood, without any underlying primary disease or associated factor. The presence of CVC, sepsis, and heart disease are factors associated with ICT. The success rate is increased with medical treatment. There was no significant difference in treatment response between the newborn and 1 month to 18-year-old patient group. It has been demonstrated that thrombus size, type, localization; sepsis, and hemoculture positivity had no impact on the treatment response.

Evaluation of renal effects of liposomal amphotericin B in children with malignancies with KDIGO and RIFLE criteria.

BACKGROUND: Amphotericin B is a broad-spectrum antifungal agent and is the backbone of the treatment for medically important opportunistic fungal pathogens in children. This study aimed to compare the nephrotoxicity associated with L-AmB in children with acute lymphoblastic leukemia and acute myeloid leukemia. MATERIALS AND METHODS: A total of 112 pediatric acute lymphoblastic leukemia or acute myeloid leukemia patients who received treatment with L-AmB (Ambisome®) at the University of Health Sciences Dr Behcet Uz Children's Hospital over 7 years were included. The incidence of hypokalemia, decreased estimated glomerular filtration rate and presence of acute kidney injury was recorded. RESULTS: The average L-AmB treatment duration was 17.1±15.0 days. Five patients (4.4%) of the patients had grade I acute renal injury according to KDIGO criteria and 16 patients (14.2%) had increased risk for kidney injury according to RIFLE criteria. There were no patients with eGFR decrease above 50% and no renal injury and failure were observed during L-AmB treatment. The rate of patients with hypokalemia in the pre-treatment was 17.9% and the post-L-AmB group was 50.0%. The rate of hypokalemia was higher in the post-treatment group (P=0.0015). Among the 112 patients, only two patients (1.7%) required cessation of L-AmB treatment due to resistant hypokalemia despite supplementation. CONCLUSIONS: Hypokalemia was more common compared to glomerulotoxicity and acute renal injury (according to KDIGO and RIFLE criteria) in pediatric leukemia patients treated with L-AmB. Hypokalemia developed in nearly half of the patients and the study shows the need for randomized controlled trials and strategies for hypokalemia associated with L-AmB treatment.

Thrombolysis with Systemic Recombinant Tissue Plasminogen Activator in Children: A Multicenter Retrospective Study

Objective: This study aimed to evaluate systemic thrombolysis experiences with recombinant tissue plasminogen activator (rtPA). Materials and Methods: Retrospective data were collected from 13 Turkish pediatric hematology centers. The dose and duration of rtPA treatment, concomitant anticoagulant treatment, complete clot resolution (CCR), partial clot resolution (PCR), and bleeding complications were evaluated. Low-dose (LD) rtPA treatment was defined as 0.01-0.06 mg/kg/h and high-dose (HD) rtPA as 0.1-0.5 mg/kg/h. Results: Between 2005 and 2019, 55 thrombotic episodes of 54 pediatric patients with a median age of 5 years (range: 1 day to 17.75 years) were evaluated. These patients had intracardiac thrombosis (n=16), deep vein thrombosis (DVT) (n=15), non-stroke arterial thrombosis (n=14), pulmonary thromboembolism (PE) (n=6), and stroke (n=4). The duration from thrombus detection to rtPA initiation was a median of 12 h (range: 2-504 h) and it was significantly longer in cases of DVT and PE compared to stroke, non-stroke arterial thrombosis, and intracardiac thrombosis (p=0.024). In 63.6% of the episodes, heparin was initiated before rtPA treatment. LD and HD rtPA were administered in 22 and 33 of the episodes, respectively. Concomitant anticoagulation was used in 90% and 36% of the episodes with LD and HD rtPA, respectively (p=0.0001). Median total duration of LD and HD rtPA infusions was 30 h (range: 2-120 h) and 18 h (2-120 h), respectively (p=0.044). Non-fatal major and minor bleeding rates were 12.5% and 16.7% for LD and 3.2% and 25.8% for HD rtPA, respectively. At the end of the rtPA infusions, CCR and PCR were achieved in 32.7% and 49.0% of the episodes, respectively. The most successful site for thrombolysis was intracardiac thrombosis. HD versus LD rtPA administration was not correlated with CCR/PCR or bleeding (p>0.05). Conclusion: Systemic thrombolytic therapy may save lives and organs effectively if it is used at the right indications and the right times in children with high-risk thrombosis by experienced hematologists with close monitoring of recanalization and bleeding.

Which tests can most effectively indicate the clinical phenotype of paediatric haemophilia patients with prophylaxis?

Patients with haemophilia A who have similar FVIII levels show clinical heterogeneity, and 10-15% of patients with severe haemophilia do not have a severe bleeding phenotype. The aim of this study was to assess whether global haemostasis tests, such as thrombin generation assay (TGA) and thromboelastography (TEG), can predict the bleeding pattern of severe haemophilia better than trough levels and pharmacokinetic profiles, particularly in the prophylactic setting. The study group consisted of 39 patients with haemophilia A and 75 healthy controls. The annual bleeding rate (ABR) and Hemophilia Joint Health Score 2.1 (HJHS) of the patients were determined. Basal factor FVIII, inhibitor levels, TEG and TGA of participants with prophylaxis were performed after a washout period. Then, a recombinant FVIII product was administered to patients. After factor replacement, the above tests were repeated at 30 min, 6 and 48 h. There was a significant difference in the ABR and HJHS between the groups according to the basal factor VIII activity of patients after wash-out. TEG and TGA parameters of patients with factor activity above 1% were significantly better than those of patients with factor activity below 1%. After factor concentrate administration, factor activities, TEG and TGA parameters at 30 min, 6 and 48 h were similar in the two groups. We showed that the 1% trough level but not for the 3% trough level is critical for both clinical phenotypes and thrombin generation for haemophilia patients in the prophylactic setting.

Effect of pyridoxine plus pyridostigmine treatment on vincristine-induced peripheral neuropathy in pediatric patients with acute lymphoblastic leukemia: a single-center experience.

BACKGROUND: Vincristine (VCR), which is a key component of chemotherapy, is important for survival. VCR is associated with a well-known side effect, including neurotoxicity. AIMS: The aim of this study was to evaluate the features of vincristine-induced peripheral neuropathy (VIPN) and the effectiveness of pyridoxine plus pyridostigmine therapy in children with acute lymphoblastic leukemia. METHODS: The WHO and NCI CTCAE neurotoxicity scorings were used to evaluate VIPN at diagnosis, in the first month, and after the third month of the treatment. The clinical features of 23 patients having acute lymphoblastic leukemia with VIPN during the period of July 2013-February 2016 were prospectively evaluated. RESULTS: The mean age was 72.8 ± 51.6 months, and 26.1%, 56.5%, and 17.4% were in standard, moderate, and high-risk groups, respectively. Neuropathy frequently occurred at induction (82.6%) and reinduction (17.4%) of the protocol. Drop foot (82.6%), leg pain (82.6%), and difficulty in walking (82.6%) were observed. The mean total cumulative dose of neuropathy occurrence was 5.6 ± 2.03 mg/m2. Our study showed that both the WHO and NCI CTCAE scorings were significantly improved via pyridoxine plus pyridostigmine therapy. CONCLUSION: The WHO and NCI CTCAE scorings may be used for evaluating neuropathy at diagnosis and follow-up of neurotoxicity with treatment. Pyridoxine plus pyridostigmine therapy may be an effective option in the treatment of VIPN.

Identification of novel TUBB1 variants in patients with macrothrombocytopenia.

Background/aim: Macrothrombocytopenia is an autosomal-dominant disorder characterized by increased platelet size and a decreased number of circulating platelets. The membrane skeleton and the link between actin filaments of the skeleton and microtubules, which consist of alpha and beta tubulin [including the tubulin beta-1 chain (TUBB1)] heterodimers, are important for normal platelet morphology, and defects in these systems are associated with macrothrombocytopenia. Materials and methods: In this study, we sequenced the exons of the TUBB1 gene using DNA isolated from the peripheral blood samples of healthy controls (n = 47) and patients with macrothrombocytopenia (n = 37) from Turkey. The TUBB1 expression levels in fractioned blood samples from patients and healthy controls were analyzed by RT-qPCR and Western blot. Microtubule organization of the platelets in the peripheral blood smears of patients, and in mutant TUBB1-transfected HeLa cells, were analyzed by immunofluorescence staining. Results: A new TUBB1 c.803G>T (p.T178T) variant was detected in all of the control and patient samples. Importantly, we found 3 new heterozygous TUBB1 variants predicting amino acid substitutions: G146R (in 1 patient), E123Q (in 1 patient), and T274M (in 4 patients); the latter variant was associated with milder thrombocytopenia in cancer patients treated with paclitaxel. Ectopic expression of TUBB1 T274M/R307H variant in HeLa cells resulted in irregular microtubule organization. Conclusion: Further clinical and functional studies of the newly identified TUBB1 variants may offer important insights into their pathogenicity in macrothrombocytopenia.