Monitoring of pediatric patients with malignant hematological diseases after allogeneic HSCT: Serbian experience.

We describe the implementation of short tandem repeats-polymerase chain reaction (STR-PCR) chimerism analyses coupled with reverse transcription PCR detection of recurrent translocations characteristic for childhood leukemia in monitoring of patients after allogeneic hematopoietic stem cell transplantation in Serbia and the first clinical results thereof. Chimerism and minimal residual disease were regularly analyzed from blood and marrow samples of 26 pediatric patients taken after stem cell transplantation with a median follow-up of 17.6 months. Our results demonstrate that STR-based chimerism monitoring is sufficient in establishing the origin of engrafted cells after transplantation and in detecting graft rejection, but more specific and more sensitive method is necessary for identifying patients with threatening leukemia relapse.

Veno-occlusive disease in pediatric patients after hematopoietic stem cell transplantation: relevance of activated coagulation and fibrinolysis markers and natural anticoagulants.

Prediction of veno-occlusive disease (VOD), its precise diagnosis, and treatment have been the subject of various studies, but still remain unclear. Our goal was to investigate the levels of activated coagulation and fibrinolysis markers and natural anticoagulants in pediatric patients with VOD after hematopoietic stem cell transplantation (HSCT). We investigated 47 pediatric patients: 20 with neuroblastoma, 17 with leukemias, and 10 with lymphomas and measured the values of antithrombin (AT), protein C (PC), fibrinogen (FI), thrombin AT complex, prothrombin fragments 1+2 (F1+2), and D-dimer from day -7 to day +30 post-HSCT. Patients were monitored for the occurrence of VOD, and it occurred in 10 patients at a median post-HSCT day of 17.5 (range: 2 to 28 d). In the VOD group, at baseline the levels of FI were significantly lower, and on days +7 and +14 a relevant difference existed in F1+2 levels. The levels of PC were significantly lower on day +14. Logistic multivariate regression analysis between the groups showed significantly different D-dimer levels on day +14. On day +30, the levels of PC, AT, and F1+2 were different between these 2 groups of patients. The levels of D-dimer and F1+2 were increased, and PC and FI decreased before the clinical onset of VOD. The parameter differences may have a predictive value in VOD onset, which makes them candidates to be routinely monitored in patients after HSCT.

Secondary hemophagocytic lymphohistiocytosis in a child with Leptospira infection: A case report.

Jevtic D, Djokic D, Redzic D, Aleksic D, Parezanovic M, Pasic S. Secondary hemophagocytic lymphohistiocytosis in a child with Leptospira infection: A case report. Turk J Pediatr 2018; 60: 735-738. Leptospirosis caused by spirochetes of the genus Leptospira in most patients result in very mild illness without jaundice. However, a small portion of patients develop various complications due to the involvement of multiple organ systems. Hemophagocytic lymphohistiocytosis is characterized by prolonged fever, hepatosplenomegaly and cytopenias, hyperferritinemia and hypertriglyceridemias, hyperfibrinogenemia, and hemophagocytosis in bone marrow, lymph nodes, spleen, or liver. Hemophagocytic lymphohistiocytosis associated with leptospirosis is a very rare condition and it should be considered in patients with multiple organ dysfunctions, together with adequate laboratory findings. It can delay the correct diagnosis of leptospirosis and contribute to an adverse outcome. We present a 13-year-old girl with secondary hemophagocytic lymphohistiocytosis caused by leptospira infection and favorable outcome with appropriate antibiotics and corticosteroid therapy.

Diagnostic relevance of ADAMTS13 activity: evaluation of 28 patients with thrombotic thrombocytopenic purpura - hemolytic uremic syndrome clinical diagnosis.

INTRODUCTION: The significance of ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin motif-13) activity for diagnosis and therapy of thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS) is still a controversial issue. OBJECTIVE: The aim of this report was to analyze the value of ADAMTS13 measurements in the diagnosis of TTP and HUS. METHODS: At presentation, we analyzed patients with idiopathic TTP (n = 18), secondary TTP (n = 4), diarrhea positive HUS (n = 3) and diarrhea negative HUS (n = 3) treated in Belgrade, Serbia from 2004 to 2010. ADAMTS13 activity from acute phase samples was measured using the residual collagen binding activity assay at the Haemophilia and Thrombosis Centre, Milan, Italy. RESULTS: There was a significant correlation between reduced ADAMTS13 activity and idiopathic TTP diagnosis (p = 0.000) as well as between lower ADAMTS13 activities and higher reticulocytes (p = 0.017) and lactate dehydrogenase levels (p = 0.027). Significant correlation was also found between higher protease activity and diagnosis of HUS (p = 0.000). There was a statistically significant correlation between higher ADAMTS13 activities and higher platelets count (p = 0.002), blood urea nitrogen (p = 0.000), and creatinine level (p = 0.000). CONCLUSION: Severe ADAMTS13 deficiency points at the diagnosis of idiopathic TTP and it is present in the secondary TTP but not in HUS.

Clinical experience in treatment of thrombotic thrombocytopenic purpura--hemolytic uremic syndrome with 28 patients.

BACKGROUND: Neither optimal treatment nor significance of ADAMTS13 (A Desintegrin And Metalloprotease with ThromboSpondin type 1 repeats) activity for diagnosis and therapy of thrombotic thrombocytopenic purpura (TTP) and hemolytic-uremic syndrome (HUS) have not been defined yet. The aim of the report is to analyze response to different volumes of plasma exchange (PE), and relationship to ADAMTS13. DESIGN AND METHODS: 28 patients clinically diagnosed with idiopathic TTP (n = 18), secondary TTP (n = 4), atypical HUS (n = 3) and typical HUS (n = 3) manifested 31 acute episodes. Patients were treated with PE in 26, and with plasma transfusion in 5 episodes with additional different therapies. RESULTS: PE volumes were as follows: 1 in 7, 1.5 in 3, 2 in 14, and intensifying schedule (1 to 1.5) in 2 episodes. Procedure number was lower in patients treated with 2 and 1.5 (p = 0.019) than in those treated with 1 volume exchange and PE intensifying, respectively (p = 0.010). PE response rate was 25/26 (96.15%). Exacerbation frequency was higher in idiopathic TTP patients (3/19) treated with 1 compared with patients treated with > 1 volume exchange (p = 0.003). Survival rate was 25/28 (89.29%). ADAMTS13 activity was reduced in 22 with severe deficiency in 14 patients. CONCLUSION: Patients responded to different treatments regardless of ADAMTS13 activity, requiring less PEs with larger volume exchanges.

Mobilization and harvesting of peripheral blood stem cells in pediatric patients with solid tumors.

Survival of patients with high-risk pediatric solid tumors has improved with the introduction of a high-dose chemotherapy regimen and autologous stem cell rescue. Here, we present our data regarding the evaluation of the efficacy and safety of hematopoietic stem cell mobilization and harvesting in children with solid tumors. From November 2002 to March 2010, 85 children underwent autologous peripheral blood stem cell collection; 35 (41.1%) of them weighed less than 20 kg and were diagnosed with neuroblastoma, Wilms' tumor, medulloblastoma, yolk sac sarcoma, or non-Hodgkin's lymphoma. The mobilization regimens included disease-specific chemotherapy plus granulocyte colony-stimulating factor in most of the patients. The median age and weight at the time of apheresis was 36 months and 13.5 kg, respectively. Large-volume leukapheresis was performed with the aim of reducing the psychological and financial impact of leukapheresis by reducing the number of procedures while collecting a large number of cells. The median number of mobilization and leukapheresis procedures per case was one. The pre-apheresis CD34+ cell count ranged from 2 to 845 µL, with a median of 24 µL. A median of four patient blood volumes was processed per procedure, lasting 279 min (range, 113-420 min). A radial catheter was used for harvesting in 35 procedures (71.4%). The median yield of CD34+ cells was 6.6×10(6) /kg per patient. The targeted dose of 5×10(6) /kg CD34+ cells was realized in 80% of patients. The tolerance of peripheral blood stem cell collection in our patients was good. In conclusion, the collection of peripheral blood stem cells is an effective and safe procedure, even when conducted on the youngest children.

Coagulation disturbances in paediatric patients with hepatic veno-occlusive disease after stem cells transplantation.

INTRODUCTION: Hepatic veno-occlusive disease (VOD) is a life threatening complication after stem cells transplantation (SCT). Its prediction, precise diagnosis and treatment remain unclear. OBJECTIVE: Our goals were to determine the incidence, outcome and changes in haemostatic parameters in patients with VOD. Also, we tried to determine coagulation disturbances and their practical significance in early diagnosis of such patients. METHODS: We prospectively evaluated all consecutive VOD patients after SCT, aged 3 months to 17 years, from February 2004 to July 2008 treated at the Mother and Child Health Institute of Serbia "Dr Vukan Cupic" (IMD). All patients were diagnosed according to the Seattle criteria. The values of PT, aPTT, fibrinogen, FVIII, AT and vWF were measured on the day prior to the initiation of conditioning regiment and on the days 1, 7 and 14 from the moment of VOD diagnosis. Laboratory testing was performed in the IMD haemostasis laboratory and results were statistically evaluated. RESULTS: During the study period 74 SCT were performed at IMD. VOD developed 11 patients; 10 of 46 were autologous and 1 of 28 allogeneic SCT patients. In our group of patients the incidence of VOD was 14.8%. VOD was classified as mild in 7, moderate in 1 and severe in 3 patients. At the moment of establishing the diagnosis all patients had a significantly increased activity of vWF, FVIII and fibrinogen, and decreased AT. All of them were dependent on platelet transfusions. CONCLUSION: Platelet transfusion dependence suggests coagulation activation with great significance and indicates a possible development of VOD. Our results also suggest that monitoring coagulation parameters levels in the first five days from the establishment of diagnosis may have a significant predictive value for VOD outcome.

Burkitt lymphoma-induced ileocolic intussusception in Wiskott-Aldrich syndrome.

A 12-year-old patient with Wiskott-Aldrich syndrome (WAS) was referred because of recurrent abdominal pain and bloody stools. Ileocolic invagination was diagnosed and resection of the terminal ileum was performed. Pathologic examination identified submucosal tumor as the leading point of intussusception. Immunohistochemistry confirmed the diagnosis of Burkitt lymphoma. The use of chemotherapy with anti-CD20 monoclonal antibody led to complete clinical remission of lymphoma. Non-Hodgkin's lymphoma (NHL) accounts for more than 60% of the tumors in children with primary immunodeficiency, and it is the most common type of malignancy observed in WAS. Burkitt lymphoma represents 40% to 50% of all NHL cases in childhood, but in WAS it has rarely been reported. Mutation analysis of the WASP gene in this patient revealed missense mutation (105 C > T) in exon 1. WAS protein (WASP) of normal size was present at a reduced amount in peripheral blood lymphocytes. Complete lack of expression of WASP carries a greater risk for severe infections, bleeding, or malignancy development in WAS. However, rare patients with residual expression of mutated WASP, like this patient, still may develop lymphomas.

[C-reactive protein and cytokines in the diagnosis of neonatal sepsis].

INTRODUCTION: Accurate evaluation and correct treatment of neonates for possible sepsis still represent the most challenging clinical tasks. Early diagnosis of neonatal sepsis is largely based on the measurement of serum concentrations of different mediators of systemic inflammation, as well as, on a group of proteins named acute phase reactants. Among acute phase reactants, C-reactive protein (CRP) has been the most extensively used and investigated so far. SYNTHESIS AND BIOLOGICAL ROLE OF CRP: This article reviews current knowledge on the synthesis, structure and biologic roles of CRP. Also, we present our original results in regard to the kinetics of serum CRP concentration during the first 24 hours of systemic injection, as well as different patterns of CRP dynamics associated with the initial choice of antibiotics, complications and the final outcome of systemic injection. INTERLEUKINS AND PROCALCITONIN IN DIAGNOSIS OF SEPSIS: Because CRP is specific, but somewhat late marker of neonatal sepsis, possible diagnostic use of other indicators of inflammation, i.e. interleukins 6 and 8, and procalcitonin during neonatal sepsis is also considered. The theoretical advantage of these early indicators is discussed in comparative analysis of the time of their activation after initial infections stimuli. CONCLUSION: In conclusion, we point to the diagnostic accuracy of serial measurements of serum CRP levels. As an alternative, simultaneous measurement of CRP and serum levels using a faster marker, such as procalcitonin, is recommended.