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Publication Metadata only A case of Burkitt’s lymphoma mimicking peritonitis carcinomatosa(Turkish Society of Hematology, 2020) Örnek, Serdar; Tecimer, Tülay; Büyüktaş, Deram; Ferhanoğlu, Ahmet Burhan; Doctor; Faculty Member; School of Medicine; School of Medicine; N/A; 18320N/APublication Metadata only Bringing packed red blood cells to the point of combat injury: are we there yet?(Galenos Yayınevi, 2018) Unlu, Aytekin; Yilmaz, Soner; Uyanik, Metin; Petrone, Patrizio; Cetinkaya, Riza Aytac; Eker, Ibrahim; Urkan, Murat; Ozgurtas, Taner; Avci, Ismail Yasar; Zeybek, Nazif; Yalçın, Özlem; Aksu, Ali Cenk; Faculty Member; PhD Student; School of Medicine; Graduate School of Health Sciences; 218440; N/AObjective: 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((R)). Operational vibrations of potential casualty transport mediums such as Sikorsky helicopters, Kirpi((R)) 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 meehanical 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. / Amaç: Kan kayıpları, hastane öncesi dönemdeki yaralanmalara bağlı ölümlerin en sık sebebidir. Türk ordusu için en kötü senaryoları ve olası ihtiyaçları araştırdık. Çatışma alanından nakil esnasında kan kaynaklarını kullanmayı planladığımız için nakil işleminden kaynaklı mekanik stresin eritrosit konsantreleri üzerine etkisini analiz edilmiştir. Gereç ve Yöntemler: İn vitro çalışmalar ASELSAN®’ın dış ortam test laboratuvarlarında gerçekleştirildi. Çatışma alanında kan taşıma işleminde kullanılması muhtemel olan Sikorsky helikopteri ve Kirpi® araçlarının operasyonel vibrasyonları ve NATO MIL-STD-810G titreşim standart yazılımı kayıt altına alındı. NATO standardının en güçlü titreşime neden olduğu hesaplandı. Kan saklama çantası içindeki 15 ünite taze (≤7 gün) ve 10 ünite taze olmayan eritrosit konsantresi (>7 gün), NATO standardı olan mekanik strese maruz bırakıldı. Titreşim TDS v895 Medium-Force Shaker cihazı tarafından simüle edildi. Simülasyonun 0., 6. ve 24. saatinde biyokimyasal ve biyomekanik analiz için kan örnekleri alındı. Bulgular: Taze ve taze olmayan eritrosit konsantreleri sırasıyla ortalama 4,9 [standart deviasyon (SD) ±2,2] ve 32,8 (SD ±11,8) günlüktü. Taze eritrosit konsantrelerinde 6. saatte gelişen mekanik hasar; artmış eritrosit fragmentasyonu (p=0,015), hemoliz oranı (p=0,003) ve supernatant potasyum (p=0,015) düzeyleri ile gösterildi. Taze olmayan eritrosit konsantrelerinin 6. saatte hemoliz oranı (p=0,015) ve supernatant potasyum düzeyi (p=0,015) yükselirken, hematokrit değerleri (p=0,015) düştü. İlk 6 saat içerisinde taze eritrosit konsantrelerinin 2’si (%13) transfüze edilebilir kalitede kalırken, taze olmayanların ise hiçbirisi uygun değildi. Sonuç: Taze ve taze olmayan eritrosit konsantrelerinin hemoliz oranları, bu ürünleri muharebe sahasında taşıdığımızda, çoğunun kullanılamaz hale geleceğini göstermektedir. Halihazırda eritrositler üzerinde oluşan mekanik hasarlanmanın önüne geçebilecek bir teknoloji bulunmamaktadır. Yukarıdaki verilerin ışığı altında yeni bir ulusal proje gerçekleştirilmektedir.Publication Metadata only Charcot-Leiden crystals in acute myeloid leukemia with bone marrow necrosis(Galenos Publishing House, 2023) Yeldir, Nese; N/A; Tan, Taner; Akay, Olga Meltem; School of Medicine; Koç University HospitalN/APublication Metadata only Cytopenias in treatment-naive HIV patients: a comparison of Turkey and Somalia(İstanbul Bağcılar Eğitim ve Araştırma Hastanesi, 2022) Sarı, Öznur; Tekin, Süda; Üre, Ümit Barbaros; Kapmaz, Mahir; Faculty Member; Other; Doctor; School of Medicine; School of Medicine; N/A; Koç University Hospital; 42146; N/A; N/AObjective: Cytopenias are common complications in HIV-positive individuals, generally correlated with the stage of the disease. Prevalence of cytopenias depends on the stage of HIV infection, gender, race, geographic location, and nutritional status. The objective of this study was to determine the frequency of cytopenias in treatment-naive HIV infected patients in two ethnically, geographically and socio-economically different countries, Turkey and Somalia. Method: The study participants were all newly diagnosed adult HIVpositive patients, not on any antiretroviral treatment. The exclusion criteria included being at the age of< 18 years, the presence of hematologic and oncologic disorders, having HIV-positivity with malignancy, chronic renal failure, hepatic disease, pregnancy, acute illness (i.e., pneumonia, or gastroenteritis), opportunistic infections and congenital hematological disorders. Results: In our study, the most common type of cytopenia was normocytic normochromic anemia. Anemia was significantly more common among Somalia patients than their Turkish counterparts. The second common hematological abnormality was leucopenia among Somalian patients and thrombocytopenia among Turkish patients. Leucopenia was rare in Turkish patients. Conclusion: The hematological findings of our study have implications for the selection of antiretroviral drugs and other agents in HIV-positive individuals and also in monitoring the development of side effects. These results vary between countries with socio-economic and geographical differences. / Amaç: Sitopeni, HIV pozitif bireylerde yaygın olarak görülen ve genellikle hastalığın evresi ile ilişkili komplikasyonlardır. Sitopenilerin prevalansı HIV enfeksiyonunun evresine, cinsiyete, ırka, coğrafi konuma ve beslenme durumuna bağlıdır. Bu çalışmanın amacı etnik, coğrafi ve sosyoekonomik olarak farklı iki ülkede, Türkiye ve Somali’de tedavi görmemiş HIV ile enfekte hastalarda sitopeni sıklığını değerlendirmektir. Yöntem: Çalışmaya katılanların tümü, herhangi bir antiretroviral tedavi almayan, yeni teşhis edilmiş yetişkin HIV pozitif hastalardı. Dışlama kriterleri, 18 yaşından küçük olmak, hematolojik ve onkolojik bozuklukların varlığı, malignitesi olan HIV pozitif hastalar, kronik böbrek yetmezliği, karaciğer hastalığı, hamilelik, akut hastalık (yani, pnömoni veya gastroenterit), fırsatçı enfeksiyonlar ve konjenital hematolojik bozukluklar idi. Bulgular: Bu çalışmada en sık görülen sitopeni normositik normokromik anemi idi. Anemi, Somalili hastalarda Türk hastalara göre önemli ölçüde daha yaygındı. Somalili hastalarda ikinci sık görülen hematolojik anormallik lökopeni, Türk hastalarda ise trombositopeni idi. Türk hastalarda lökopeni nadirdi. Sonuç: Çalışmamızın hematolojik bulguları, HIV pozitif bireylerde antiretroviral ilaçların ve diğer ajanların seçiminde ve ayrıca yan etkilerin gelişiminin izlenmesinde çıkarımlara sahiptir. Bu sonuçlar sosyo-ekonomik ve coğrafi farklılıklara sahip ülkeler arasında farklılık göstermektedir.Publication Metadata only Early changes of mannose-binding lectin, H-ficolin, and procalcitonin in patients with febrile neutropenia: a prospective observational study(Galenos Yayincilik, 2016) Mutçalı, Sibel Islak; Saltoğlu, Neşe; Balkan, İlker İnanç; Özaras, Reşat; Yemişen, Mücahit; Mete, Bilgül; Tabak, Fehmi; Mert, Ali; Öztürk, Recep; Öngören, Seniz; Başlar, Zafer; Aydın, Yıldız; Soysal, Teoman; N/A; Ferhanoğlu, Ahmet Burhan; Faculty Member; School of Medicine; Koç University Hospital; 18320Objective: The significance of mannose-binding lectin (MBL) and H-ficolin deficiency in febrile neutropenic (FN) patients and the correlation of these markers along with consecutive C-reactive protein (CRP) and procalcitonin (PCT) levels during the infectious process are investigated. Materials and Methods: Patients with any hematological malignancies who were defined to have "microbiologically confirmed infection", "clinically documented infection", or "fever of unknown origin" were included in this single-center prospective observational study. Serum levels of CRP, PCT, MBL, and H-ficolin were determined on 3 separate occasions: at baseline (between hospital admission and chemotherapy), at the onset of fever, and at the 72nd hour of fever. Results: Forty-six patients (54% male, mean age 41.7 years) with 61 separate episodes of FN were evaluated. Eleven patients (23.9%) had "microbiologically confirmed infection", 17 (37%) had "clinically documented infection", and 18 (39.1%) had "fever of unknown origin". Fourteen (30.4%) patients had low (<500 ng/mL) initial MBL levels and 7 (15.21%) had low (<12,000 ng/mL) H-ficolin levels. Baseline MBL and H-ficolin levels did not significantly change on the first and third days of fever (p=0.076). Gram-negative bacteremia more frequently occurred in those with low initial MBL levels (p=0.006). PCT levels were significantly higher in those with microbiologically documented infections. Mean and median PCT levels were significantly higher in cases with bacteremia. There was no significant difference between hemoculture-positive and-negative patients in terms of CRP levels. Conclusion: Monitoring serum H-ficolin levels was shown to be of no benefit in terms of predicting severe infection. Low baseline MBL levels were correlated with high risk of gram-negative bacteremia; however, no significant correlation was shown in the follow-up. Close monitoring of PCT levels is warranted to provide more accurate and specific data while monitoring cases of bacteremia.Publication Metadata only Intravascular large B-cell lymphoma within the appendix presenting as acute abdomen: a challenging diagnosis for hematologists(Galenos Yayıncılık, 2021) N/A; N/A; N/A; N/A; N/A; N/A; Atalar, Semra Cemre; Akay, Olga Meltem; Osmanbaşoğlu, Emre; Masyan, Helin; Taşkın, Orhun Çığ; Ferhanoğlu, Ahmet Burhan; Undergraduate Student; Faculty Member; Doctor; Doctor; Faculty Member; Faculty Member; School of Medicine; School of Medicine; N/A; N/A; School of Medicine; School of Medicine; Koç University Hospital; 346260; 170966; N/A; N/A; 166686; 18320N/APublication Metadata only Myeloproliferative neoplasms and aspirin: does increased platelet turnover matter?(Galenos Yayınevi, 2022) Gokturk, Ilgin Kocak; Ozunal, Isil Erdogan; Gokturk, Alican; Kaya, Ali Hakan; Yilmaz, Gueven; Ozturk, Erman; N/A; Akay, Olga Meltem; Faculty Member; School of Medicine; 170966Objective: Platelet aggregation tests and the analysis of thromboxane A2 metabolites [serum thromboxane B2 (TXB2) and urine 11-dehydro TXB2] are used to evaluate the efficacy of aspirin. In myeloproliferative neoplasms (MPNs), the immature platelet fraction (IPF) rises due to enhanced platelet turnover, and this has been thought to reduce the efficacy of aspirin. This phenomenon is overcome by the recommendation of aspirin intake in divided doses. We aimed to evaluate aspirin efficacy in patients who were receiving aspirin treatment of 100 mg/day.Materials and Methods: Thirty-eight MPN patients and 30 control patients (non-MPN patients who received a single daily dose of aspirin at 100 mg for nonhematological conditions) were enrolled. IPF, serum TXB2, and urine 11-dehydro TXB2 levels were measured and aggregation tests with arachidonic acid and adenosine diphosphate were performed by light transmission aggregometry (LTA).Results: Mean IPF and TXB2 levels were higher in the MPN group (p=0.008 and p=0.003, respectively). IPF levels were lower in patients on cytoreductive therapy in the MPN group (p=0.001), but these values were similar between patients on hydroxyurea and the non-MPN group (p=0.72). TXB2 levels did not differ according to hydroxyurea treatment status but were higher in the MPN group compared to non-MPN patients (23.63 ng/mL and 19.78 ng/mL, respectively; p=0.04). TXB2 values were higher in patients with essential thrombocythemia and a history of thrombotic events (p=0.031). No difference was observed in LTA between the MPN and non-MPN patient groups (p=0.513).Conclusion: Higher levels of IPF and TXB2 in the MPN patient group indicated platelets that could not be inhibited by aspirin. It was observed that patients under cytoreductive therapy had lower IPF values, but the expected decrease in TXB2 levels was not observed. These findings suggest that a lack of response to aspirin may be due to additional intrinsic factors rather than increased platelet turnover. /Amaç: Aspirin etkinliğini değerlendirmek için, trombosit agregasyon testleri ile tromboksan A2 metabolitlerinin analizi [serum tromboksan B2 (TXB2) ve idrar 11-dehidro TXB2] kullanılmaktadır. Myeloproliferatif neoplazilerdeki (MPN) artmış trombosit döngüsü, immatür trombosit fraksiyonunun (İTF) artışına sebep olmakta, bunun da aspirin etkinliğini azalttığı düşünülmektedir. Bu durumu aşmak için, aspirinin bölünmüş dozlarda verilmesi önerilmektedir. Çalışmamızda, günde tek doz 100 mg aspirin tedavisi alan hastalardaki aspirin etkinliğini değerlendirmeyi amaçladık. Gereç ve Yöntemler: Otuz sekiz MPN tanılı hasta ile 30 kontrol hastası (hematolojik olmayan durumlar sebebiyle günde tek doz 100 mg aspirin kullanan, MPN tanısı olmayan hastalar) çalışmaya alındı. İTF, serum TXB2 ve idrar 11-dehidro TXB2 düzeylerine bakıldı. Işık transmisyon agregometride (ITA) agregasyon testleri yapıldı. Bulgular: Hasta grubunun TXB2 ve İTF mutlak değer ölçümleri, kontrol grubuna göre anlamlı düzeyde yüksek görüldü (sırasıyla p=0,008 ve p=0,003). Hidroksiüre alan hastaların İTF değerleri hidroksiüre almayan hastalardan daha düşük (p=0,001), ancak kontrol grubu ile benzerdi (p=0,72). TXB2 seviyeleri hidroksiüre alan ve almayan hastalarda değişiklik göstermedi, ancak MPN grubunda kontrol grubuna göre daha yüksek saptandı (sırasıyla 23,63 ng/mL ve 19,78 ng/mL, p=0,04). Tromboz öyküsü olan esansiyel trombositemi hastalarında TXB2 seviyeleri daha yüksek görüldü (p=0,031). Gruplar arasında ITA ile bakılan trombosit agregasyon testlerinde anlamlı bir farklılık izlenmedi (p=0,513). Sonuç: MPN hasta grubundaki daha yüksek İTF ve TXB2 seviyeleri, aspirin tarafından inhibe edilememiş trombositler olduğunu gösterdi. Sitoredüktif tedavi altındaki hastaların İTF değerlerinin daha düşük olduğu, ancak TXB2 seviyelerinde beklenen düşüşün olmadığı görüldü. Bu bulgular aspirin yanıtsızlığının, artmış trombosit döngüsünden ziyade intrinsik ek faktörlere bağlı olabileceği kanaatini oluşturmaktadır.Publication Metadata only Recognizing pinch purpura as the first manifestation of light-chain amyloidosis(Galenos Yayincilik, 2018) N/A; N/A; Öztürk, Erman; Akay, Olga Meltem; Ferhanoğlu, Ahmet Burhan; Doctor; Faculty Member; Faculty Member; N/A; School of Medicine; School of Medicine; Koç University Hospital; N/A; N/A; N/A; 170966; 18320N/APublication Metadata only The changing epidemiology of bloodstream infections and resistance in hematopoietic stem cell transplantation recipients(2016) Yemişen, Mücahit; Balkan, İlker İnanc; Salihoğlu, Ayşe; Eşkazan, Ahmet Emre; Mete, Bilgül; Ar, M. Cem; Öngören, Seniz; Başlar, Zafer; Özaras, Reşat; Saltoğlu, Neşe; Mert, Ali; Özturk, Recep; Tabak, Fehmi; Soysal, Teoman; N/A; Ferhanoğlu, Ahmet Burhan; Faculty Member; School of Medicine; Koç University Hospital; 18320Objective: Patients receiving hematopoietic stem cell transplantation (HSCT) are exposed to highly immunosuppressive conditions and bloodstream infections (BSIs) are one of the most common major complications within this period. Our aim, in this study, was to evaluate the epidemiology of BSIs in these patients retrospectively. Materials and Methods: The epidemiological properties of 312 patients with HSCT were retrospectively evaluated. Results: A total of 312 patients, followed between 2000 and 2011, who underwent autologous (62%) and allogeneic (38%) HSCT were included in the study. The most common underlying malignancies were multiple myeloma (28%) and Hodgkin lymphoma (21.5%). A total of 142 (45%) patients developed at least 1 episode of BSI and 193 separate pathogens were isolated from the blood cultures. There was a trend of increase in the numbers of BSIs in 2005-2008 and a relative increase in the proportion of gram-positive infections in recent years (2009-2011), and central venous catheter-related BSI was found to be most common source. Coagulase-negative staphylococci (49.2%) and Acinetobacter baumannii (8.8%) were the most common pathogens. Extended-spectrum beta-lactamase-producing strains were 23% and 22% among Escherichia coli and Klebsiella spp. isolates, respectively. Quinolone resistance was detected in 10% of Enterobacteriaceae. Resistance to carbapenems was not detected in Enterobacteriaceae, while it was seen at 11.1% and 23.5% in Pseudomonas and Acinetobacter strains, respectively. Conclusion: A shift was detected from gram-negative bacteria to gram-positive in the etiology over the years and central lines were the most common sources of BSIs.