The effect of serum lipid levels on peripheral blood hematopoietic stem cell levels.

INTRODUCTION: There are limited numbers of available retrospective studies on various hematological diseases treated with stem cell mobilization therapy. In the present study, we aimed to demonstrate the effects of serum lipid levels on peripheral blood CD34+ (PBCD34+) cell counts as well as the changes in serum lipid levels during stem cell mobilization process. METHOD: PBCD34+ cell counts were compared between hypercholesterolemic patients and healthy individuals. Additionally, total cholesterol (TChol), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), and triglyceride (TG) levels were measured from healthy donors who underwent stem cell mobilization, at different time points (prior to filgrastim [phase 1], prior to apheresis [phase II], and the first week following apheresis [phase III]. RESULTS: In the hypercholesterolemia group, the PBCD34+ cell count was found to be higher among patients with elevated LDL-C (2.6 ± 0.35/µL vs. 1.7 ± 0.17/µL, p = 0.003) and TChol (2.6 ± 0.34/µL vs. 1.7 ± 0.14/µL, p = 0.006) in comparison to the healthy controls. In the mobilization group, phase II HDL-C levels (35.3 ± 2.8 mg/dL) were found to be lower than both phase I (45.6 ± 2.1 mg/dL) and phase III (44.5 ± 2.6 mg/dL) (p = 0.007). Phase II TChol levels (183.5 ± 10.0 mg/dL) were lower than both phase I (216.8 ± 8.5 mg/dL) and phase III (212.2 ± 8.4 mg/dL) (p = 0.02). At phase II, there was an inverse correlation between PBCD34+ cell count and HDL-C (r = - 0.57, p = 0.003). DISCUSSION: Our results indicate that, while increased LDL-C level is the determinant of baseline PBCD34+ cell count, reduced HDL-C is the determinant of PBCD34+ cell count during mobilization process.

Therapeutic plasma exchange in hypertriglyceridemic patients

Background/aim: High triglyceride (TG) levels are associated with increases in atherosclerotic cardiovascular disease (CVD), hepatic steatosis, and pancreatitis. Acute pancreatitis is a condition with high mortality. Therapeutic plasma exchange (TPE) in the treatment of hypertriglyceridemic pancreatitis (HTGP) is a rapid and effective treatment modality. In this study, the results of TPE were evaluated and the frequency of lipoprotein lipase (LPL) mutation in these patients was determined. Materials and methods: TPE was performed in 31 patients with HTGP at the Adult Therapeutic Apheresis Center. Results: A TG level under 500 mg/dL was achieved by applying apheresis at a median of 2 times (IQR 2­2, min 1, max 6) in the 31 cases. LPL mutation was detected in 8 (25.8%) of the 31 hypertriglyceridemia cases. When TG levels before and after TPE were evaluated, the mean TG level before TPE was significantly higher (3132 ± 1472 mg/dL) than the mean TG level afterwards (948 ± 465 mg/dL, P < 0.001). This result represented a decrease of 69.7% TG after TPE. Conclusion: TPE is a safe, fast, and effective treatment modality in experienced centers.

Therapeutic plasmapheresis in thyrotoxic patients.

PURPOSE: For the treatment of thyrotoxicosis, alternative treatment modalities may be necessary if anti-thyroid drugs cannot be used due to side effects, inefficiencies, or there is a need to start a rapid action such as thyroid storm. By using therapeutic plasma exchange (TPE), it is possible to effectively and rapidly remove the increased thyroid hormones. We evaluated our results and experience on a rapid, effective, and reliable alternative treatment modality in thyrotoxic patients. METHODS: TPE was performed in 46 thyrotoxic patients at the Adult Therapeutic Apheresis Center. RESULTS: Forty six patients with a median age of 30 years (interquartile range [IQR] 30-50) were assessed. In 40 (87%) of the cases, the diagnosis was Graves' disease. The other causes of thyrotoxicosis were amiodarone-induced thyrotoxicosis (n = 4) and toxic nodular goiter (n = 2). The median and IQR of fT3 values in patients before TPE were 9.9 (6.5-16.8) pg/mL (N: 2.3-4.2) and the median and IQR of fT4 values were 2.9 (2.3-4.1) ng/dL (N: 0.74-1.52). When the procedure was terminated, the median and IQR of fT3 values in patients were 4.0 (3.1-5.2) pg/mL and the median and IQR fT4 values were 1.6 (1.4-2.0) ng/dL. The decrease in both free thyroid hormones was found to be statistically significant (p < 0.000). CONCLUSION: Our study is the largest series of TPE in the literature used for thyrotoxicosis. In the light of the literature and our results, we conclude that TPE is an effective alternative treatment option to prepare for ablative treatment for cases that have side effects or ineffectiveness of anti-thyroid drugs.

Epidemiology and analysis of invasive fungal infections in patients withhematological malignancies: a single-center real-life experience

Background/aim: Invasive fungal infection (IFI) causes morbidity and mortality among patients with hematological malignancies. We evaluated the incidence and treatment characteristics of IFIs between October 2012 and December 2013. Materials and methods: Patients who received chemotherapy or stem cell transplantation were retrospectively evaluated. Fungal infections were classified according to EORTC criteria.Results: Prophylaxis and antifungal therapy were given in 30.5% and 23.6% of 522 chemotherapy courses, respectively. The incidence of proven/probable IFI was 6.7%. The incidence of IFI among patients who received prophylaxis was significantly higher than among those who did not receive it (11.3% vs. 4.6%, P = 0.005). There was no significant difference between patients who received mold-active and no mold-active prophylaxis (P = 0.098). The most common single agent therapy and causative pathogen was liposomal amphotericin B (57.1%) and Aspergillus (n = 5), respectively. IFI-attributable mortality rate was 14.2% in 6 weeks.Conclusion: The IFI incidence and mortality rate were similar to that reported in the literature. The IFI rate was higher in the group using prophylaxis, as this is a high-risk group. Although the IFI rate was not significantly different between groups using prophylaxis, patients should be followed closely for the effective use of posaconazole prophylaxis.

Cholesterol Levels in Patients with Chronic Lymphocytic Leukemia.

Low cholesterol levels may be accompanied by solid tumors or hematological malignancies such as multiple myeloma. Decreased cholesterol levels have been reported in some experimental studies about chronic lymphocytic leukemia (CLL). It may be associated with tumoral cell metabolism. Herein, we examine blood lipid profiles of patients with newly diagnosed CLL (284 male, 276 female, mean age 64 ± 11 years) as defined by National Cancer Institute criteria. The control group consisted of 71 healthy subjects with mean age 55 ± 9 years (28 male, 43 females). 60% of patients with Binet A, while 25% were Binet C. Decreased levels of total cholesterol, high density lipoprotein (HDL) and low density lipoprotein (LDL) were observed in patients with CLL than control group (p < 0,001). There was no statistical significance between CLL and control group for triglycerides (TG) and very low density lipoprotein (VLDL), also between HDL-C, VLDL, TG and grades. Cholesterol may metabolized by abnormal lymphocytes in CLL patients.

Effect of centrifugation time on growth factor and MMP release of an experimental platelet-rich fibrin-type product.

Platelet-rich fibrin (PRF) has a controlled release of growth factors due to the fibrin matrix structure. Different centrifugation protocols were suggested for PRF preparation. Since the derivation method of PRF can alter its contents, in the present study it is aimed to investigate the cell contents and transforming growth factor beta-1 (TGF-ß1), platelet-derived growth factor (PDGF-AB), vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-1 and-8 release from experimental PRF-type membranes obtained with different centrifugation times at 400 gravity. Three blood samples were collected from 20 healthy non-smoker volunteers. One tube was used for whole blood analyses. The other two tubes were centrifuged at 400 g for 10 minutes (group A) or 12 minutes (group B). Each experimental PRF-type membrane was placed in Dulbecco's Modified Eagle's Medium (DMEM)and at 1, 24 and 72 hours, TGF-ß1, PDGF-AB, VEGF, MMP-1 and -8 release amounts were analysed by enzyme-linked immunosorbent assay (ELISA). The blood cell count of membranes was determined by subtracting plasma supernatant and red blood cell (RBC) mixture from the whole blood cell counts. At 72 hours, the VEGF level of group B was statistically higher than that of group A (p = 0.040). The centrifugation time was not found to influence the release of other growth factors, enzymes and cell counts. Within the limits of the present study, it might be suggested that centrifugation time at a constant gravity has a significant effect on the VEGF levels released from experimental PRF-type membrane. It can be concluded that due to the importance of VEGF in the tissue healing process, membranes obtained at 12-minute centrifugation time may show a superior potential in wound healing.

Intravascular large B-cell lymphoma diagnosed on prostate biopsy: a case report.

Intravascular large B-cell lymphoma (IVLBCL) is a very rare type of non-Hodgkin lymphoma, usually affecting elderly patients and characterized by selective infiltration of neoplastic cells within blood vessels' lumina. IVLBCL diagnosed with prostatic involvement is extremely rare. We report a patient of 65 years old, having mostly neurological complaints but diagnosed with IVLBCL upon histopathological examination of transurethral prostate resection material, which revealed large neoplastic cell infiltration totally limited within the lumens of small vessels. By immunohistochemistry, neoplastic cell infiltration was positive with MUM1, bcl-6, and bcl-2 and negative with ALK1, CD10, and CD30, with a high Ki-67 proliferation index. CD34 and CD31 staining showed expression in endothelial cells, highlighting the intravascular nature of neoplastic infiltrate. The patient unfortunately refused to receive treatment and died of the disease 8 months after the diagnosis. IVLBCL, though very rare, should be considered in differential diagnosis of all organ biopsies with intravascular infiltration. Further improvements in the understanding of the pathogenesis and biology of this rare type of lymphoma are mandatory.

The loss of CD34+ cells in peripheral hematopoietic stem cell products cryopreserved by non-controlled rate freezing and stored at -80 °C after overnight storage.

Although peripheral blood stem cell (PBSC) products cryopreserved by non-controlled rate freezing and stored at -80 °C after overnight storage are used frequently, data regarding the rate of loss of CD34+ cells in these products are limited. In this prospective study, CD34+ cells were counted at three (fresh, post-overnight and post-thaw) points in 83 PBSC products from 41 patients by flow cytometry. Compared to fresh products, the mean losses of post-overnight and post-thaw total CD34+ cells are 16.3% and 38.4% (p = 0.02), and the mean losses of post-overnight and post-thaw viable CD34+ cells are 16.5% and 48.5%, respectively (p < 0.001). The numbers of fresh viable, post-thaw total and post-thaw viable CD34+ cells were inversely correlated with the durations of neutrophil and platelet engraftment. Our results indicate that the mean loss of post-thaw total and viable CD34+ cells is approximately 20% higher than that observed in standard cryopreservation methods. In addition, fresh viable, post-thaw total and especially post-thaw viable CD34+ cell levels are valuable predictors of both neutrophil and platelet engraftments.

CD31 expression on peripheral blood stem cells predicts both early neutrophil and platelet engraftments.

No detailed information currently exists about the immune phenotypic profiles of peripheral blood stem cells (PBSCs) obtained by different mobilization regimens. The effects of these profiles on the outcome of transplantation are largely unknown. In this prospective study, the surface immune phenotypic features (CD11a, CD18, CD31, CD38, CD44, CD62e, CD62L, CD90, CD117, CD135 and CD184 expression) of sorted PBSCs that had been mobilized by growth factor with (group I and group II) or without (group III) disease-specific chemotherapies were investigated. The immune phenotypic features on mobilized PBSCs in groups I, II and III were not significantly different. The CD31 (platelet endothelial cell adhesion molecule-1) positivity ratio on PBSCs inversely correlated with both the duration of neutrophil (r=-0.32, p=0.03) and platelet (r=-0.36, p=0.02) engraftment. No relationship was found between the engraftment (neutrophil and platelet) durations and CD184 (chemokine receptor CXC motif receptor 4 [CXCR4]) expression on PBSCs. We demonstrated that the surface immune phenotypic profiles on PBSCs obtained by several mobilization regimens were not different. To our knowledge, this is the first study to demonstrate that CD31 expression on human PBSCs may positively affect both neutrophil and platelet engraftment. Contrary to our expectations, CD184 (CXCR4) expression on PBSCs has no effect on neutrophil or platelet engraftment. Considered together, our results suggest that additional surface antigens (such as CD31) may be more effective in the homing process.

Risk factors for a poor hematopoietic stem cell mobilization.

Poor mobilization is an important problem in autologous stem cell transplantation. We retrospectively reviewed the data of 165 mobilized patients to identify possible risk factors for a poor stem cell mobilization. 27 patients (16.4%) were categorized as poorly mobilized. The poor mobilization ratio differed according to diagnosis (lymphoma: 25.4%, acute leukemia: 15.4%, amyloidosis: 14.3%, and multiple myeloma: 9.6%). Being diagnosed as lymphoma (odds ratio [OR]=6.02, p=0.001), advanced age (OR=1.05, p=0.007) and increased weight (OR=1.03, p=0.03) were found as possible risk factors. Being diagnosed as lymphoma was shown to be the most important risk factor for a poor mobilization. Leukapheresis staff should be aware of the increased risk of a poor mobilization in lymphoma patients and remobilization methods should be considered from the beginning.

The clearance time of infused hematopoietic stem cell from the blood circulation.

There is no detailed information about the clearance time of infused hematopoietic stem cell (HSC) from the blood circulation in humans. In this prospective study, peripheral blood CD34+ cell counts were detected during the 4days period following autologous HSC transplantation in 20 patients by means of flow cytometry. The median CD34+ cells were at the highest level in the first hour and decreased below pre-infusion values on the first day after HSC infusion. By nonparametric analysis, positive correlation was found between CD34+ cell levels at the first hour and the post-thaw CD34+ cell dose (r=0.57, p=0.01). An inverse correlation was determined between CD34+ cell levels at the first hour and neutrophil engraftment (r=-0.54, p=0.01). Compared with the patients having CD34+ cell count of ⩾2µL(-1) in the first hour following HSC infusion, the patients having CD34+ cell count of <2µL(-1) had delayed both neutrophil (20 vs. 12, p=0.008) and platelet (47 vs. 11, p=0.01) engraftments. Our results indicated that infused HSCs were removed from the blood circulation within 1day. In addition, CD34+ cell levels at the first hour may be used as an important indicator to predict the delay of neutrophil and platelet engraftments.

The difference in lactate dehydrogenase activity between pre- and post-mobilization periods is a good indicator of successful stem cell mobilization.

Predicting poor stem cell mobilization may prevent the costs and complications associated with remobilization. We retrospectively reviewed the relationship between serum lactate dehydrogenase (sLDH) activity and peripheral blood CD34 (PBCD34) cell counts in 46 granulocyte colony stimulating factor (G-CSF) induced mobilization cycles with or without chemotherapy. A significant correlation between post-mobilization (pre-apheresis) sLDH activity and PBCD34 count was found (r(s)=0.43, p=0.007). A strong correlation was shown between the pre- and post-mobilization sLDH activity difference and PBCD34 count (r(s)=0.55, p=0.001). With respect to sLDH activity differences; (a) all patients with a difference of >300 U/L, (b) 71% of patients with a difference of 100-300 U/L, and (c) 44% of patients with a difference of <100 U/L were considered to have good mobilizations. The sLDH activity difference between pre- and post-mobilization is a good indicator of successful mobilization. According to our results, the success of mobilization can be predicted based on sLDH activity differences; (i) good mobilization if the difference is >300 U/L, (ii) intermediate risk if the difference is 100-300U/L, and (iii) high risk if the difference is <100 U/L.

Plerixafor use in patients with previous mobilization failure: A multicenter experience.

Plerixafor in conjunction with G-CSF (G-P) is an effective strategy for hematopoietic stem cell mobilization in patients with previously failed mobilization attempt. Here we report our results with G-P among patients with at least one mobilization failure with G-CSF alone (G) or G-CSF plus chemotherapy (G-C). The study included 20 consecutive patients with lymphoma and myeloma from five centers. In 14 (70%) patients, a minimum of 2×10(6)/kg CD34+ stem cells were collected and 16 out of 20 patients (80%) were able to proceed to ASCT. Our study indicates that plerixafor can safely rescue patients with a history of mobilization failure.

Acquired activated protein C resistance in sarcoma patients.

Acquired activated protein C resistance (aAPCR) is seen more frequently in solid and hematological cancer patients. We aimed to investigate the presence of aAPCR and the frequency of clinically detectable thrombosis in sarcoma patients. Normalized activated protein C sensitivity ratio (nAPCSR), factor V Leiden (FVL) mutation, factor V (FV) levels and factor VIII (FVIII) levels were prospectively measured in 52 patients and in 52 healthy controls. Clinically detectable thrombosis was present in one patient (1.92%). Compared with healthy controls (106%), the sarcoma patients had significantly lower values of the nAPCSR at pre (87.25%) and post (94.35%) treatment period (P < 0.0001). aAPCR was found as 4.2, 13 and 0%, respectively. The post-treatment FV levels (178.1 U/dl) were significantly (P < 0.001) higher than the pretreatment levels (147.5 U/dl). Inverse correlation was found between post-treatment FV levels and nAPCSR values (r = -0.38, P < 0.02). We found out a slightly increased frequency of venous thromboembolism in sarcoma patients. As an original finding which has not been reported previously in the literature, we also found out a decrease in the nAPCSR, persisting even after treatment. Thirdly, we found out that the significantly higher rate of aAPCR at the time of diagnosis totally disappeared after treatment.

Determining Toxoplasma high-risk autologous and allogeneic hematopoietic stem cell transplantation patients by systematic pre-transplant PCR screening of stem cell originated buffy coat.

The diagnosis of Toxoplasma infection or disease in hematopoietic stem cell transplantation (HSCT) patients is achieved mainly by PCR screening; however screening did not find wide field of use in practice due to costly expenditures of PCR. This study aimed to determine patients at high risk of Toxoplasma infection or disease before transplantation by stem cell originated buffy coat PCR and subsequently to screen them. Buffy coats collected from 12 autologous and 18 allogeneic HSCT patients' donors were investigated by PCR before transplantation. After transplantation, blood and sera collected at fixed time intervals were screened by two PCR methods and serological assays. Screening results first time assessed a toxoplasmosis incidence level as 25% in autologous HSCT patients and increased incidence level in allogeneic HSCT patients to 22%. Importantly, buffy coat PCR was first time performed before transplantation, to determine the risk of toxoplasmosis. Buffy coat PCR results showed that four patients were at high risk of toxoplasmosis before transplantation. After transplantation, these patients experienced toxoplasmosis. In conclusion, for the determination of patients at risk of toxoplasmosis, clinicians should consider buffy coat PCR in combination with serology before transplantation. After transplantation, PCR screening can be initiated in high risk patients upon clinical suspicion.

The effect of cholesterol levels on hematopoietic stem cell mobilization.

Data regarding effects of cholesterol levels on hematopoietic stem cell mobilization are limited. We retrospectively reviewed the relationship between serum total cholesterol levels and peripheral blood CD34 (PBCD34) cell counts in 52 granulocyte colony stimulating factor (G-CSF) induced mobilization cycles with or without chemotherapy. The cholesterol levels between the poor and good mobilization groups (median 172mg/dl vs. 183.5mg/dl, respectively, p=0.18) were not different. No significant correlation was obtained between the cholesterol levels and PBCD34 counts (r=0.02, p=0.85). No significant correlation was obtained between cholesterol levels and PBCD34 counts in patients neither mobilized with G-CSF alone (r=-0.02, p=0.9) nor G-CSF plus chemotherapy (r=0.04, p=0.8). The results of the study indicate that there was no effect of cholesterol on hematopoietic stem cell mobilization. Prospective cohort studies are needed to demonstrate the effect of cholesterol on mobilization and its extent in humans.

Inflammation-induced thrombosis: mechanisms, disease associations and management.

Although inflammation-induced thrombosis is a well-known entity, its pathogenesis remains complicated. There are complex interactions between inflammation and hemostasis, involving proinflammatory cytokines, chemokines, adhesion molecules, tissue factor expression, platelet and endothelial activation, and microparticles. Inflammation increases procoagulant factors, and also inhibits natural anticoagulant pathways and fibrinolytic activity, causing a thrombotic tendency. Besides, chronic inflammation may cause endothelial damage, resulting in the loss of physiologic anticoagulant, antiaggregant and vasodilatory properties of endothelium. However, inflammation- induced venous thrombosis may develop even in the absence of vessel wall damage. On the other hand, coagulation also augments inflammation, causing a vicious cycle. This is mainly achieved by means of thrombin-induced secretion of proinflammatory cytokines and growth factors. Platelets may also trigger inflammation by activating the dendritic cells. There are many systemic inflammatory diseases characterized by thrombotic tendency, including Behçet disease (BD), antineutrophilic cytoplasmic antibody-associated vasculitides, Takayasu arteritis, rheumatoid arthritis, systemic lupus erythematosus, antiphosholipid syndrome, familial Mediterranean fever, thromboangiitis obliterans (TAO) and inflammatory bowel diseases. Inflammation-induced thrombosis may respond to immunosuppressive (IS) treatment, as in the case of BD. However effectiveness of this treatment can not be generalized to all other inflammatory diseases. For instance, IS agents do not have any beneficial role in the management of TAO. Heparin, antiplatelet agents such as aspirin and clopidogrel, colchicine and statins also have some antiinflammatory activity. However, decreased responsiveness to aspirin and clopidogrel treatments may be observed in inflammatory diseases, due to antiplatelet resistance caused by systemic inflammation. In the present review, we aimed to discuss the details of the complex crosstalk between inflammation and hemostasis in the context of available data. We also intended to overview the major inflammatory diseases with thrombotic tendency, as well as to discuss the general principles of the management of inflammation-induced thrombosis.

Risk factors for microbial contamination of peripheral blood stem cell products.

BACKGROUND: Despite the well-known contamination rates and presence of microbial agents in stem cell products, the risk factors affecting microbial contamination have not been well described. STUDY DESIGN AND METHODS: In a 12-year period, we retrospectively reviewed culture results of peripheral blood stem cell products with the intent of identifying risk factors for microbial contamination. RESULTS: Microbial contamination was detected in 28 (5.7%) products of the postprocessing period and in 18 (3.66%) products of the postthawing period. Large-volume leukapheresis (LVL; odds ratio [OR], 5.85; 95% confidence interval [CI], 1.52-22.49; p = 0.01) and high numbers of stem cell culture sampling (OR, 1.4; 95% CI, 1.03-1.91; p = 0.03) were found to be risk factors for postprocessing bacterial contamination. The presence of postprocessing bacterial contamination was a risk factor for postthawing (OR, 28.89; 95% CI, 6.67-125.15; p < 0.001) and posttransplant (OR, 3.25; 95% CI, 1.24-8.50; p = 0.01) microbial growth. In transplants that were performed using contaminated products, the same pathogen was detected in 20% of patients and different pathogens were found in 35% of patients. CONCLUSION: Cultures should be carefully monitored in LVL products and in samples with high numbers of cultures performed. Growth of different bacterial pathogens must be considered in transplants that are performed with contaminated products.

Metastatic pulmonary calcinosis and leukocytoclastic vasculitis in a patient with multiple myeloma.

UNLABELLED: Both leukocytoclastic vasculitis and metastatic pulmonary calcification are conditions that rarely occur during the course of multiple myeloma. We present a multiple myeloma patient that had severe dyspnea due to metastatic pulmonary calcinosis, and ulceronecrotic skin lesions caused by leukocytoclastic vasculitis. After 3 courses of standarddose chemotherapy all skin and pulmonary lesions disappeared. Autologous peripheral stem cell transplantation was performed and during 1 year of follow-up the patient was in complete remission; after 1 year, laboratory test results indicated disease relapse. Although the patient was treated with bortezomib and dexamethasone, the disease progressed. Non-myeloablative allogeneic stem cell transplantation was performed, but despite of all treatment the patient died due to disease progression. CONFLICT OF INTEREST: None declared.