Metin Demirkaya
Uludağ University
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Featured researches published by Metin Demirkaya.
Pediatric Hematology and Oncology | 2013
Solmaz Celebi; Melike Sezgin; Deniz Cakir; Birol Baytan; Metin Demirkaya; Betül Sevinir; Sefika Elmas Bozdemir; Adalet Meral Gunes; Mustafa Hacimustafaoglu
Catheter-associated bloodstream infections (CABSIs) are common complications encountered with cancer treatment. The aims of this study were to analyze the factors associated with recurrent infection and catheter removal in pediatric hematology-oncology patients. All cases of CABSIs in patients attending the Department of Pediatric Hematology-Oncology between January 2008 and December 2010 were reviewed. A total of 44 episodes of CABSIs, including multiple episodes involving the same catheter, were identified in 31 children with cancer. The overall CABSIs rate was 7.4 infections per 1000 central venous catheter (CVC) days. The most frequent organism isolated was coagulase-negative Staphylococcus (CONS). The CVC was removed in nine (20.4%) episodes. We found that hypotension, persistent bacteremia, Candida infection, exit-side infection, neutropenia, and prolonged duration of neutropenia were the factors for catheter removal. There were 23 (52.2%) episodes of recurrence or reinfection. Mortality rate was found to be 9.6% in children with CABSIs. In this study, we found that CABSIs rate was 7.4 infections per 1000 catheter-days. CABSIs rates in our hematology-oncology patients are comparable to prior reports. Because CONS is the most common isolated microorganism in CABSIs, vancomycin can be considered part of the initial empirical regimen.
Pediatric Hematology and Oncology | 2012
Yasin Karalı; Metin Demirkaya; Betül Sevinir
The objective of the present study was to determine the type, frequency, the reason why complementary and alternative medicine (CAM) treatments are used, the factors related with their use, and the effects of CAM usage on long-term survival. Families of a total of 120 children with cancer between 0–18 years of age, including 50 (41.7%) girls and 70 (58.3%) boys, participated in our study. The authors found that 88 patients (73.3%) used at least one CAM method, the most common (95.5%) of which was biologically based therapies. Most frequently used biologically based therapies were dietary supplements and herbal products. The most commonly used dietary supplement or herbal product was honey (43.2%) or stinging nettle (43.2%), respectively. We found that patients used such CAM methods as complementary to, but not instead of, conventional therapy. Sixty-nine out of 88 patient families (78.4%) shared the CAM method they used with their physicians. No statistically significant relation was found between socioeconomic, sociodemographic, or other factors or items and CAM use. The mean follow-up period of the CAM users and nonusers groups was 79.4 ± 36.7 (21.3–217.9) and 90.9 ± 50.3 (27.4–193.7) months, respectively. Five-year survival rates for CAM users and nonusers were found as 81.5% and 86.5%, respectively (P > .05). In conclusion, families of children with cancer use complementary and alternative treatment frequently. They do not attempt to replace conventional treatment with CAM. Higher rates of CAM use was found in families with higher educational level. CAM usage did not affect the long-term survival.
Pediatric Neurology | 2010
Birol Baytan; Özlem Özdemir; Metin Demirkaya; Melike Sezgin Evim; Adalet Meral Gunes
Reversible posterior leukoencephalopathy, defined by both clinical and neuroimaging findings, can affect children receiving chemotherapy. The syndrome is characterized by hypertension, alterations in mental status, seizures, hallucinations, and acute visual changes and is associated with abnormalities seen in magnetic resonance imaging of symmetric white matter lesions, especially in the parietal and occipital lobes. The etiology of reversible posterior leukoencephalopathy is as yet unknown. Presented here are four cases of reversible posterior leukoencephalopathy induced by chemotherapy, with a brief review of the literature and consideration of possible mechanisms. A diagnosis of reversible posterior leukoencephalopathy should be considered when patients receiving cancer chemotherapy suddenly develop hypertension followed by neurologic complications, especially if presenting with seizures.
Pediatric Neurology | 2010
Metin Demirkaya; Betül Sevinir; Özlem Özdemir; Hulya Ozturk Nazlioglu; Mehmet Okan
Some children with malignancies initially present with neurologic signs. Cavernous sinus syndrome is a rare manifestation of lymphomas, more commonly reported in adults. A patient presenting with third and fourth cranial nerve palsies was initially thought to manifest Tolosa-Hunt syndrome, but during follow-up a diagnosis of lymphoma without systemic involvement was established. This patient is the youngest, to our knowledge, to be diagnosed with primary cavernous sinus lymphoma. He remains in remission 5 years after chemotherapy. Malignancies (especially non-Hodgkins lymphoma) should be considered in young children with cavernous sinus syndrome, even without systemic involvement.
Journal of Clinical Research in Pediatric Endocrinology | 2009
Erdal Eren; Metin Demirkaya; Esra Deniz Papatya Cakir; Betül Sevinir; Halil Saglam; Omer Tarim
Hepatoblastoma, an embryonal tumor, is one of the most common primary liver tumors in childhood. It secretes human chorionic gonadotropin (hCG), which can cause precocious puberty (PP). Herein, we present a case with PP who had enlarged penile size noticed during a diagnosis of hepatoblastoma. Laboratory examination revealed increased testosterone, alpha-fetoprotein (AFP), and hCG levels. Serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were within prepubertal ranges. The diagnosis of hepatoblastoma was made by liver biopsy. Chemotherapy was administered, and the patient was referred to surgery. Ten months later, testis volumes were below 4 ml bilaterally, and penile length was 5.5 cm. Serum testosterone, AFP, and hCG levels decreased. Resection of the tumor and chemotherapy are essential for the treatment of hepatoblastoma and they can eliminate the symptoms of PP. Conflict of interest:None declared.
Pediatric Hematology and Oncology | 2011
Oguzhan Durmaz; Metin Demirkaya; Betül Sevinir
Anemia, which is a common problem in cancer patients, has a negative effect on survival by decreasing the efficacy of chemotherapy and particularly of radiotherapy, as well as impairing the quality of life (QoL) of patients. Recombinant human erythropoietin (rHuEPO) decreases a patients need for transfusions and increases their QoL. The aim of this study was to evaluate the effect of weekly single-dose EPO treatment on transfusion rates, QoL, and hemoglobin (Hb) levels. In addition, patients were followed up for a long period to assess the impact of EPO treatment on survival. The study was conducted from December 2001 to December 2002 in patients with newly diagnosed lymphoma or solid tumors using a prospective and controlled design. EPO-β was given as a single dose of 450 U/kg once a week for 12 weeks. The study and control groups included 16 patients each. Hb levels measured in the study group at the 4th, 8th, and 12th weeks were significantly higher than the values recorded before the start of chemotherapy. In the control group, Hb levels post chemotherapy were significantly lower than values recorded prior to treatment. The increased Hb levels in the study group were significant at the 8th and 12th weeks of treatment compared to levels measured prior to treatment. In the control group, Hb levels at the 4th and 8th weeks were significantly lower than pretreatment levels. When the percent increase of Hb levels of the study and control groups with respect to treatment week was compared, the difference was statistically significant at the 4th, 8th, and 12th weeks. Although the increase on the performance scale within each group during treatment was significant in both the study and control groups, the increase was more marked in the study group. The percent increase on the performance scale with respect to week of treatment was higher in the study group than in the control group. In EPO treatment group, side effects were seen in 38% of patients, with 19% being local pain in the injection area, 13% local hyperemia, and 6% headache. The mean follow-up period of the study and control group was 7.03 ± 0.41 (6.0–7.41) and 7.46 ± 0.45 (6.58–7.83) years, respectively; no statistically significant difference existed between these figures. Overall survival at the end of 7 years of follow-up was 68.8% and 81.3% for the study and control groups, respectively. The use of EPO-β in lymphoma and solid tumor patients on a once-weekly regimen (450 U/kg) was determined to be effective in increasing Hb levels, decreasing transfusion rates, and improving QoL. This regimen was safe, did not cause serious side effects, and can be recommended because of its high patient compliance and tolerability. An effect of EPO on prognosis was not evident. We could not have an explanation on the effect of EPO treatment on prognosis, as there were low number of patients and advanced-staged patients died earlier. Therefore, a larger number of patients are needed to clarify the effect of EPO treatment on prognosis.
Journal of Clinical Research in Pediatric Endocrinology | 2011
Metin Demirkaya; Betül Sevinir; Halil Saglam; Lütfi Özkan; Okan Akacı
Objective: Post-treatment endocrine disturbances are common in cancer patients who have received radiotherapy or chemotherapy. The objective of this study was to evaluate the thyroid functions of long-term survivors of pediatric Hodgkin’s lymphoma treated with chemotherapy and radiotherapy. Methods: Thyroid functions of 55 Hodgkin’s lymphoma patients (M/F:2.05/1) in complete remission were evaluated retrospectively. Results: The mean age of the patients at diagnosis was 10.35±4.09 (range: 2.83-17) years and the mean follow-up period was 5.54±3.68 (range: 0.92-13.92) years. All patients received chemotherapy; a total of 50 patients (90.9%) underwent radiotherapy, 42 (76.4%) of whom received neck/mantle radiotherapy. Thyroid function tests were abnormal in 14 (24.5%) patients and normal - in the remaining 41 (74.5%). A diagnosis of subclinical and overt hypothyroidism was made in 11 (78.6%) and 3 (21.4%) patients with abnormal thyroid function tests, respectively. Nearly one-fourth (21.4%) of all thyroid function disorders were detected in the first year of follow-up. A statistically significant correlation was found between the dose of mantle radiotherapy and thyroid function disorder (p=0.002). In addition, statistically significant correlations were established between thyroid examination or thyroid ultrasonography findings and thyroid functions (p <0.001 or p=0.006, respectively). Conclusions: Radiation-induced thyroid disorders may develop in pediatric Hodgkin’s lymphoma patients in complete remission starting as early as the first year after treatment and are dose-dependent. Patients, particularly those who have been exposed to radiotherapy of the neck, must be followed up closely for occurrence of thyroid dysfunctions. Conflict of interest:None declared.
Pediatric Hematology and Oncology | 2015
Metin Demirkaya; Deniz Tugcu; Arzu Akcay; Aydogan G; Akıcı F; Salcioglu Z; Ekmekci H; Betül Sevinir; Balci Ekmekci O
In this study, we aimed to determine serum adrenomedullin levels and compare them with levels of C-reactive protein (CRP) and procalcitonin (PCT). Cancer patients aged 0–18 years who experienced febrile neutropenia attacks were included in the study. Adrenomedullin, CRP, and PCT were analyzed at admission, day 3, and days 7–10 later. Fifty episodes of febrile neutropenia that developed in 37 patients were analyzed in this study. The mean age of the patients was 7.5 ± 4.7 (1–18) years. The patients had leukemia (73%), solid tumors (19%), and lymphoma (8%). The percentages of the patients in the clinically documented infection (CDI), fever of unknown origin (FUO), sepsis, and microbiological documented infection (MDI) categories were 34%, 34%, 20%, and 12%, respectively. During the study period, four patients were lost. In the MDI group, adrenomedullin levels on day 3 were significantly higher than those in the CDI and FUO groups. PCT levels were significantly higher in the sepsis group than those in the CDI group at admission, day 3, and days 7–10. In the sepsis group, PCT levels on days 7–10 days were significantly higher than those in the sepsis group. PCT values from the deceased patients on days 7–10 were significantly higher than those from patients who survived. CRP levels did not differ significantly among the febrile neutropenia groups. First, in our study, adrenomedullin was used as a biomarker in the febrile neutropenia episodes of children with cancer. Among adrenomedullin, CRP, and PCT, procalcitonin demonstrates the highest correlation with the severity of infection.
Pediatric Hematology and Oncology | 2013
Metin Demirkaya; Solmaz Celebi; Betül Sevinir; Mustafa Hacimustafaoglu
The objective of this study was to compare the effectiveness of piperacillin–tazobactam (PIP/TAZO) plus amikacin (AMK) (PIP/TAZO+AMK) versus cefoperazone–sulbactam (CS) plus AMK (CS+AMK) for the treatment of febrile neutropenia (FN) in children with cancer. The study was designed prospectively and randomized in 0- to 18-year-old children with lymphoma or solid tumor who were hospitalized with FN diagnosis. Consecutively randomized patients received either PIP/TAZO 360 mg/kg/day in 4 doses plus AMK 15 mg/kg/day in 3 doses or CS 100 mg/kg/day in 3 doses plus AMK 15 mg/kg/day in 3 doses intravenously. Treatment modification was defined as any change in the initial empirical antibiotic therapy. A total of 116 FN episodes were managed in 46 patients (26 boys and 20 girls) with a median age of 6.5 years (range .8–17.0) during the study period. Success rates without modification of therapy were 47.5% and 52.6% in PIP/TAZO+AMK group and CS+AMK group, respectively (P >.05). No statistical difference was found between treatment groups in terms of durations of neutropenia, fever, and hospitalization. The overall success rate in all groups was 97.4%. No major side effect was observed in either group during the course of the study. Our study is the first to compare the effectiveness of PIP/TAZO+AMK and CS+AMK therapies. Both combinations were effective and safe as empirical therapy for febrile neutropenic patients.
Turkish Journal of Hematology | 2011
Betül Sevinir; Metin Demirkaya; Birol Baytan; Adalet Meral Gunes
OBJECTIVE This study aimed to examine the incidence, clinical characteristics, and outcome of hyperuricemia and tumor lysis syndrome (TLS) in children with non-Hodgkins lymphoma (NHL) and acute lymphoblastic leukemia (ALL). METHODS This retrospective study included data from 327 patients (113 NHL and 214 ALL). RESULTS Hyperuricemia occurred in 26.5% and 12.6% of the patients with NHL and ALL, respectively. The corresponding figures for TLS were 15.9% and 0.47% (p=0.001). All hyperuricemic NHL patients had advanced disease and renal involvement was present in 53%. All hyperuricemic ALL patients had a leukocyte count >50,000 mm3 at the time of diagnosis. Among the hyperuricemic NHL and ALL patients, 96.6% and 66.6% had LDH ≥500 UI/L, respectively. Treatment consisted of hydration and allopurinol; none of the patients received urate oxidase. Among the patients that developed TLS, 26.3% had laboratory TLS, 42.1% had grade I or II TLS, and 31.6% had grade III or IV TLS. Uric acid levels returned to normal after a mean period of 3.5±2.5 and 3.05±0.8 d in NHL and ALL groups, respectively. In all, 7% of the patients with hyperuricemia required hemodialysis. None of the patients died. CONCLUSION In this series the factors associated with a high-risk for TLS were renal involvement in NHL and high leucocyte count in ALL. Management with allopurinol and hydration was effective in this group of patients with high tumor burden.