Yilmaz Ay
Boston Children's Hospital
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Featured researches published by Yilmaz Ay.
Haemophilia | 2010
D. Yilmaz; M. Akin; Yilmaz Ay; Can Balkan; Ahmet Çelik; Orkan Ergün; K. Kavakli
Summary. Haemophiliacs and their families consider that circumcision is a very important step to become a member of society and it is a social obligation for men in Turkey. Although bleeding risk is high, almost all haemophiliacs would like to be circumcised in Turkish society. The aim of this study was to evaluate our experience in circumcision of haemophilia patients and define efficacy, safety and complication rates of our protocol, called ‘Izmir protocol’. In this study, we retrospectively reviewed medical records of 50 patients with haemophilia who underwent circumcision at our hospital according to Izmir protocol between 1996 and 2009. Oral tranexamic acid and fibrin glue were used in all children. One hour before the operation, first dose of factor concentrate was given. After reaching a plasma factor level of around 90–100%, the prepuce was incised circumferentially and excised using Gomco clamp or open technique under general anaesthesia. Intermittent injections of factor concentrate were given every 12 for 48 h. While the first two doses were given at higher amount to achieve or continue plasma factor level at 90–100%, in the last three doses, the aim was to maintain the plasma factor level at 50–60%. Forty‐eight hours after the circumcision, patients were discharged. Three patients (6%) showed bleeding complication and all were resolved easily. All had at least one excuse from the protocol (Lower doses of factor concentrates was used in 2, tranexamic acid was not used in 2). Izmir protocol is safe, cheap and easy to carry out.
Haemophilia | 2010
Can Balkan; Deniz Yilmaz Karapinar; Semih Aydogdu; Coşkun Özcan; Yilmaz Ay; M. Akin; K. Kavakli
Summary. This report evaluates the haemostatic efficacy of recombinant factor VIIa (rFVIIa) and activated prothrombin complex concentrate (APCC) in patients with haemophilia and high responding inhibitors who underwent major and minor surgery. Data pertaining to surgeries from 2001 to 2009 at a single centre were retrospectively analysed. During this period, 53 surgical procedures were performed in 30 haemophiliacs with high responding inhibitors. Mean age was 16.2 ± 9.4 years. Eleven major surgeries in 4 patients, 41 radioisotope synovectomies (RS) and one circumcision classified as minor surgery in 28 patients were performed. Among the major surgery procedures, four were treated with rFVIIa, five with APCC and two with sequential use of APCC and rFVIIa. We used rFVIIa at the dosage of 80–120 μg kg−1 every 2 h and APCC 100 IU kg−1 every 12 h for the major surgery. When performing RS, we used rFVIIa in 18 patients with 26 target joints and APCC in 9 patients with 15 target joints. Three consecutive doses of rFVIIa (90 μg kg−1) were used at 2‐h intervals followed by additional three doses at 6‐h intervals. The initial dose of APCC was 75 IU kg−1 followed by a second and third dose of 50 IU kg−1 at 12‐h intervals. APCC and rFVIIa demonstrated excellent efficacy in our major and minor surgical interventions [100% (22/22) and 94% (31/33), respectively]. We had only two bleeding complications with rFVIIa. There were no thromboembolic complications. APCC and rFVIIa provide an effective and safe first line haemostatic therapy for inhibitor‐positive haemophiliacs, allowing both major and minor surgery to be successfully performed.
Haemophilia | 2012
Yilmaz Ay; C. Balkan; Deniz Yilmaz Karapinar; M. Akin; B. BilenoĞlu; K. Kavakli
Monitoring factor replacement treatment and observing concordance with clinical haemostasis is crucial in vital haemorrhages and major surgeries in haemophilic patients. We aimed to investigate the value of the thrombin generation assay (TGA) and thromboelastography (TEG) for monitoring haemostasis in haemophilic patients during factor replacement treatment. The study group consisted of 29 patients (21 haemophilia A, 8 haemophilia B). All the patients FVIII‐inhibitor were negative. A total of 35 bleeding episodes and/or surgical interventions were evaluated. aPTT, FVIII/FIX activity, TEG and TGA tests were conducted before and after factor therapy during the bleeding episode or surgical prophylaxis of haemophilic patients. Correlations among these tests were evaluated and compared with clinical responses. No correlation was found among aPTT, factor activities and clinical outcome. There were also no correlation found between TEG parameters and clinical outcome. The only significant correlation found between TGA parameters and clinical outcome was the correlation between peak thrombin. In conclusion, we found superiority of TGA‐peak thrombin over other traditional tests for monitoring haemostasis in haemophilic patients in this study.
Clinical and Applied Thrombosis-Hemostasis | 2013
Yilmaz Ay; Can Balkan; Deniz Yilmaz Karapinar; M. Akin; Basri Bilenoğlu; K. Kavakli
Background: Monitoring bypassing agent therapy and observing concordance with clinical hemostasis is crucial in vital hemorrhages and major surgeries in patients with hemophilia having inhibitor. Objective: We aimed to investigate the value of the thrombin generation assay (TGA) and thromboelastography (TEG) for monitoring hemostasis in patients with hemophilia having inhibitor, during supplementation therapy with bypassing agents. Patients and Methods: The study group consisted of 7 patients with hemophilia having factor VIII inhibitor. All patients were male. The median age of the participants was 10 years. Age range was 6 to 32 years. The median inhibitor level was 10 Bethesda units (BU), with a range of 5 to 32 BU. A total of 17 bleeding episodes were evaluated. Both TEG and TGA tests were assessed in addition to clinical responses. Assessments were made prior to bypass agent therapy such as recombinant factor VIIa (rFVIIa) or activated prothrombin complex concentrate (aPCC) for bleeding episodes, during the first hour and 24 hours after either intervention in patients. Results: No relation between clinical response and TGA or TEG parameters was found in patients. There was no difference between clinical responses after rFVIIa and aPCC treatments. However, after aPCC treatment, endogenous thrombin potential and peak thrombin levels and also TEG R, K, and alpha angle degrees were significantly higher. Conclusions: In conclusion, we found that the clinical effectiveness of bypass therapy in hemophilia cannot be assessed by TGA and TEG.
Blood Coagulation & Fibrinolysis | 2016
Yilmaz Ay; Tuba Hilkay Karapınar; Yeşim Oymak; Ersin Töret; Bengü Demirağ; Dilek Ince; Esin Albudak Ozcan; Nergial Moueminoglou; Sultan Aydin Koker; Canan Vergin
Immune thrombocytopenic purpura (ITP) results from accelerated platelet destruction mediated by autoantibodies to platelet glycoproteins. Some patients with chronic ITP are refractory to all therapies [steroids, intravenous immunoglobulin (IVIG), anti-D and immunosuppresive drugs] and have chronic low platelet counts and episodic bleeding. We retrospectively evaluated the efficacy and safety of rituximab treatment and splenectomy in paediatric patients diagnosed with chronic and refractory ITP who were unresponsive to steroids, IVIG, cyclosporine and mycophenolate mofetil. Records of patients with chronic and refractory ITP in 459 patients with primary ITP who were followed up in our hospital from January 2005 to December 2014 were reviewed. Fifteen of patients received rituximab and/or applied splenectomy. Fifteen chronic ITP patients (10 boys, five girls) with a mean age of 10 years were enrolled in the study. Two of these patients were suffering from Evans syndrome. The median time since diagnosis of ITP was 10 years. The median follow-up duration after starting Rituximab and splenectomy were 13 and 9.5 months, respectively. None of the seven patients who were treated with rituximab achieved a response. A splenectomy was performed in six of the seven patients who had been treated with rituximab. Complete and partial responses were achieved in 67 and 33% of the patients, respectively. We evaluated the clinical characteristics and responses of chronic ITP patients who did not receive rituximab therapy and underwent a splenectomy. The success rate was 100% in the eight patients with chronic and refractory ITP. Rituximab therapy might not be beneficial for some children with severe chronic ITP who are refractory to standard agents. A splenectomy might be useful and preferable to rituximab.
Transfusion and Apheresis Science | 2015
Yeşim Oymak; Yüce Ayhan; Tuba Hilkay Karapinar; İlker Devrim; Yilmaz Ay; Hafize Sarihan; Canan Vergin
The granulocyte transfusion (GTX) has been used for a long time due to uncontrolled neutropenic fever with antimicrobial agents. In some cases, the product needs to be splitted for using in the next 12 hours. The aim of this study is to evaluate the efficacy of splitted product and clinical response to GTX. In this study, 15 patients with malignancy with 19 neutropenic fever, who had received 56 GTX, were included. Seventeen of 56 GTX were splitted and used in maximum 12 hours during infections which did not respond to antibacterial and antifungal therapy in 7 days. The patients were divided in to response groups as a complete, partial and progressive. The predictive factors for response group were evaluated. GTX were well tolerated in all patients. The median granulocyte dose was 1.26 (0.38-5.22) × 10(9)/kg. Total response rate was 89.5%. The infection-related mortality rate was 10.5%. Although the granulocyte doses are the same in both of the product groups, an hour later ANC increment of primer product was higher than that of splitted product (p = 0.001). Among the products, 48.7% of primer product and 17.6% of splitted product had induced ≥ 1000/mm(3) ANC increment after an hour (p = 0.039). Granulocyte transfusion is safe and effective in controlling the febrile neutropenia attack. GTX should be applied in a short time to provide effective ANC increment. For now, main granulocyte product instead of splitted product should be preferred in case of uncontrolled neutropenic fever with antibacterial/antifungal agents.
Turkish Journal of Hematology | 2016
Mine Düzgöl; Gulcihan Ozek; Nuri Bayram; Yeşim Oymak; Ahu Kara; Bengü Demirağ; Tuba Hilkay Karapınar; Yilmaz Ay; Canan Vergin; İlker Devrim
Primary varicella-zoster virus (VZV) infection is a benign self-limited disease. In this study, we review our experience in focusing on the outcome and treatment of VZV infection in pediatric malignancy patients. During the study period, a total of 41 patients with pediatric malignancy had been hospitalized with the diagnosis of VZV infection. All the patients were treated with intravenous acyclovir for a median of 7 days (ranging from 5 to 21 days). The calculated attributable delay of chemotherapy due to VZV infections was 8 days (ranging from 2 to 60 days). VZV-related complications were observed in 3 of 41 patients (7%) who suffered from acute respiratory distress syndrome, and one of them with hemophagocytic lymphohistiocytosis died due to respiratory failure despite acyclovir and broad-spectrum antimicrobial treatment plus supportive treatment. VZV infections are still important contagious diseases in pediatric cancer patients, because they cause not only significant mortality but also a delay in chemotherapy.
Turkish journal of haematology : official journal of Turkish Society of Haematology | 2015
Yeşim Oymak; Tuba Hilkay Karapınar; Yilmaz Ay; Esin Albudak Ozcan; Neryal Muminoglu; Sultan Aydin Koker; Ersin Töret; Afig Berdeli; Erkin Serdaroglu; Canan Vergin
To the Editor, Atypical hemolytic uremic syndrome (aHUS) is a rare multigenic disorder characterized by thrombotic microangiopathy (TMA). Among the genes that are associated with aHUS, mutations in the complement factor H (CFH) gene are the most common genetic cause of the disease. Several specific gene mutations have been identified in patients with aHUS [1,2,3]. A 5-year-old boy was admitted to our hospital with fatigue. Physical examination revealed pallor and hepatomegaly. His blood pressure was within the normal range. A blood smear showed hemolysis with 10% schistocytes and polychromasia. He had anemia with 5.5 g/ dL hemoglobin level and 14.6% reticulocyte level. He had also thrombocytopenia (48,000/mm3) and elevated lactate dehydrogenase (LDH) as 1066 U/L. A direct Coombs test was negative. The other blood parameters of the patient were as follows: haptoglobin 5 mg/dL (reference range: 41-165 mg/dL), C3 122 mg/dL (reference range: 79-152 mg/dL), creatinine level 0.5 mg/dL, blood urea nitrogen 12 mg/dL, and indirect bilirubin 7 mg/dL. Urine analysis was normal. On the second day of admission, the patient’s thrombocyte count dropped to 38,000/mm3, his LDH level remained elevated, and schistocytes were still present on his peripheral blood smear. As for the blood smear and other TMA symptoms, first plasmapheresis was started, which lasted 20 weeks. Then treatment was continued with 600 mg of eculizumab weekly for the first three weeks and followed by once every 2 weeks (total 11 doses). Although the patient had TMA symptoms he didn’t have renal insufficiency. Also ADAMTS-13 activity was 48% (reference range: 40%-130%) and ADAMTS-13 antibody was negative. Four months after stopping eculizumab, the patient’s levels of hemoglobin, thrombocytes, reticulocytes, haptoglobin and LDH were 11 g/dL, 150,000/mm3, 0.87%, 46.4 mg/dL (reference range: 41-165 mg/dL) and 385 U/L, respectively. Informed consent was obtained for genetic testing and publishing the patient’s data from his parents. DNA sequencing analysis of the patient revealed a homozygous p.His402Tyr mutation due to a p.1204 C>T change in exon 9, a homozygous p.Ala307Ala mutation due to a p921A>C change in exon 7 and a heterozygous p.Ala473Ala mutation due to a p.1419G>A change in exon 10 of the CFH gene (Figure 1).
Journal of Pediatric Hematology Oncology | 2016
Tuba Hilkay Karapınar; Yeşim Oymak; Yilmaz Ay; Sultan Aydin Koker; Ersin Töret; Filiz Hazan; Canan Vergin
Chronic neutropenia (CN) is defined as neutropenia that persists for >3 months; it is caused by a heterogeneous group of diseases in children. The aim of the present study was to evaluate the significance and clinical manifestations of CN in children at a single children’s hospital. Between October 2004 and April 2014, CN patient data were evaluated retrospectively. Thirty-one patients were assessed in this study. Thirteen of them (41.9%) were younger than 12 months of age at initial diagnosis. There was no difference in the absolute number of neutrophils at diagnosis between the children aged younger than 12 months and those aged 12 months and older at CN onset. Twenty-two of the patients (70.9%) were diagnosed during treatment for acute infections. A total of 11 patients (35.5%) were hospitalized because of recurrent infections. Most of the recurrent infections occurred in the lungs (81.8%). Congenital neutropenia (CoN) was identified in 14 patients (45.1%). Eight of 14 patients (57.1%) required granulocyte-colony stimulating factor treatment, and none of them experienced adverse effects from this treatment. Fifteen patients (48.3%) were diagnosed with idiopathic neutropenia. Comparison between the idiopathic and CoN groups revealed no differences in age, the absolute number of neutrophils, or the presence of infection at diagnosis; however, differences were detected in sex and the rate of spontaneous recovery from neutropenia. Ten of the patients (32.2%) experienced spontaneous recovery from neutropenia during a follow-up period of 7 to 52 months. In current study, we found a higher CoN ratio in the CN patients compared with previous reports, which may be due to the high rate of consanguineous marriages in our country. However, the finding of CN requires several laboratory investigations, prolonged follow-up, and advanced molecular analysis, and its etiology can remain idiopathic.
Blood Coagulation & Fibrinolysis | 2016
Yeşim Oymak; Neryal Muminoglu; Yilmaz Ay; Tuba Hilkay Karapınar; Sultan Aydin Koker; Ersin Töret; Aşiyan K. Ylmaz; Müge Gürçnar; Canan Vergin
Central nervous system bleeding, which can be a life-threatening complication, is seen in 2.7% of patients with haemophilia. Spinal epidural haematomas represent about one-tenth of such cases. Here, we report on a 10-month-old boy with severe haemophilia A, who presented with torticollis. Although administration of factor VIII at a dose of 50 U/kg, the patient developed flaccid paralysis of the upper extremities. Factor VIII inhibitor screen was positive. Magnetic resonance imaging of the spine revealed spinal epidural haematomas, extending from C-1 to the cauda equina. Treatment was continued with recombinant activated factor VIIa without surgery. After 1 month, complete neurological recovery was achieved and fully resolved haematomas were detected on spinal MRI. A prompt radiological evaluation of the cervical spine with MRI should be made in patients with haemophilia presenting with torticollis. In addition, in the case of life-threatening bleeding in patients with haemophilia, the possibility of an inhibitor should be kept in mind.