Hemophagocytic lymphohistiocytosis (HLH) is an aggressive life-threatening disease that consists of uncontrolled activated lymphocytes and macrophages that secrete excessive cytokines. Symptoms and laboratory findings of HLH include prolonged fever, cytopenia, hepatosplenomegaly, liver dysfunction, hypertriglyceridemia, hyperferritinemia, increased soluble interleukin-2 receptor, low fibrinogen, and neurological problems. HLH has two forms: primary (familial autosomal recessive) or secondary (related to infections, malignancy, autoimmune and metabolic disorders, transplantations, chimeric antigen receptor T-cell therapies, etc.) form. As underlying conditions in HLH varied, clinical findings are nonspecific and disease diagnosis is challenging. Furthermore, patients diagnosed with primary HLH can have a secondary triggering agent, such as infection. Thus, there is no clear-cut distinction between these two forms. Abnormal immune response and a low number or absence of natural killer cells and cytotoxic T-lymphocytes are hallmarks of HLH. Despite the early and aggressive treatment, HLH is a deadly disease. Urgent immunosuppressive therapy is necessary to control hyperinflammation. Hematopoietic stem cell transplantation is a curative treatment in familial forms. Targeted therapy with emapalumab was also recently reported to be effective.

Children,extremity,hemangioma,vascular malformation

Objective: Neurofibromatosis (NF) is the most common autosomal dominantly inherited neurocutaneous syndrome. The characteristic features of NF type 1 (NF-1) are café au lait spots, axillary and inguinal freckling, peripheral neurofibromas, optic pathway glioma, and Lisch nodules. The present study aimed to analyze the clinical features of children with NF-1. Materials and Methods: In this study, the children with NF-1 diagnosed and followed-up in our center between 2000 and 2020 were retrospectively evaluated. Demographic and clinical features of patients were defined. Results: The study group consisted of 52 patients. Of those, 25 were boys and 27 were girls. The children’s median age at diagnosis was 5.9 years (1-15.8). Café au lait (CAL) spots and axillary/ inguinal freckling were observed in 50 and 24 patients, respectively. Neurofibroma was present in 22 cases. Ten of the cohort had optic gliomas, and 39 of them had cranial hamartomas. Orthopedic complications such as scoliosis, tibial pseudoarthrosis, and osteoporosis were observed in 13 patients. Eleven children had neurocognitive disorders. Conclusions: Early diagnosis is important in neurofibromatosis to prevent the complications of the disease. Also, neurological development and secondary malignancy follow-up should be done carefully in this group of patients. Cite this article as: Kaçar AG, Kılınc Oktay B, Çınar Özel S, et al. Neurofibromatosis type 1 in children: A single-center experience. Turk Arch Pediatr. 2021; 56(4): 339-343.

Objective: This study aimed to compare bone marrow aspirate (BMA) multicolor flow cytometry (MFC) analysis and bone marrow biopsy (BMB) in detecting bone marrow (BM) involvement in children with neuroblastoma (NB) at diagnosis and during follow-up. Materials and Methods: A total of 132 BM samples from 39 patients (M/F ratio: 19/20; median age: 38 months) with neuroblastoma were simultaneously obtained for evaluation. The samples were investigated for BM involvement using BMB and MFC. Results: A comparison between MFC (n: 60) and BMB (n: 60) was possible for 120 samples. When BMB was considered as the reference standard, MFC had diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of 86%, 58%, 54%, and 88%, respectively, and values of 90%, 57%, 60%, and 89%, respectively, at diagnosis. The median proportion of CD45−/CD56+ cells in MFC was 0.028% (range 0–35%). The event-free survival (EFS) rates for MFC (+) and MFC (−) patients according to the analysis results of the BM samples at the time of diagnosis were 70.6% and 81.8%, respectively (p = 0.607), and the overall survival (OS) rates were 88.2% in MFC (+) patients and 90.9% in MFC (−) patients (p = 0.583). Conclusion: Multicolor flow cytometry may be used as an adjunct to cytomorphology to achieve more sensitive and accurate results as an objective, quantitative method with fast results in detecting bone marrow involvement in children with NB.

Eltrombopag (EPAG) added to standard immunosuppressive therapy (IST) was associated with higher overall (OR) and complete response (CR) rates in patients with treatment-naïve severe aplastic anemia (SAA) in adults, but the clinical evidence on the efficacy of EPAG in children with acquired aplastic anemia is limited and controversial. We compared the efficacy and safety of EPAG combined with IST (n=38) versus IST alone (n=57) as a front-line treatment for pediatric patients with SAA. The EPAG+IST group had higher CR and OR rates at 3 and 6 months, although 1-year OR, CR, and partial response (PR) rates showed no significant difference between two groups. Older age at diagnosis (>8.95 years) was associated in the EPAG+IST group with higher OR rates at 6 months and 1-year (p=0.007, p=0.005, respectively). The addition of EPAG to IST did not demonstrate superiority over IST alone in terms of overall survival (OS) and event-free survival (EFS) in this study; with 1-year EFS of 81.1% for EPAG+IST and 71.3% for IST, and with 1-year OS of 89.2% vs. 80.4%. Eltrombopag induced a faster response compared to those receiving IST alone without increasing toxic effects, but EPAG does not confer additional benefits regarding OS or relapse rates in children. Notably, older age at diagnosis in the EPAG+IST group was significantly associated with improved response rates.

Platelets play a role in hemostasis, thrombosis, and vascular integrity. They also play a major role in the development of inflammation and the activation of immune responses. They have phagocytic activity, stimulate the secretion of immune modulators, and activate other immune cells, which results in platelet-neutrophil aggregation, platelet-induced neutrophil degranulation, and the formation of neutrophil extracellular traps. Data on 124 febrile neutropenia attacks were retrospectively examined. Patients’ age, sex, diagnosis, and relapse history were obtained. The complete blood count levels on the first and last febrile day of the febrile neutropenia attacks, duration of fever, and number, type, and timing of thrombocyte suspension transfusions were recorded. The patients were divided into three groups according to the day of fever when the platelet suspension was administered (1 day, 2–3 days, and >3 days); the duration of fever was compared between the three groups. The fever duration of those who were transfused with platelet suspension on the first day of fever was found to be significantly shorter (p = 0.03 and p < 0.001, respectively). When treating a patient with febrile neutropenia, if thrombocyte suspension transfusion is indicated, transfusing thrombocytes in the first days of fever shortens the fever duration and improves the prognosis of febrile neutropenia attack, supporting the hypothesis that not only neutrophils but also platelets may play a role in fighting against microorganisms.