COVID-19 disease in children and adolescents following allogeneic hematopoietic stem cell transplantation: A report from the Turkish pediatric bone marrow transplantation study group.

BACKGROUND: Data on the risk factors and outcomes for pediatric patients with SARS-CoV-2 infection (COVID-19) following hematopoietic stem cell transplantation (HSCT) are limited. OBJECTIVES: The study aimed to analyze the clinical signs, risk factors, and outcomes for ICU admission and mortality in a large pediatric cohort who underwent allogeneic HSCT prior to COVID-19 infection. METHOD: In this nationwide study, we retrospectively reviewed the data of 184 pediatric HSCT recipients who had COVID-19 between March 2020 and August 2022. RESULTS: The median time from HSCT to COVID-19 infection was 209.0 days (IQR, 111.7-340.8; range, 0-3845 days). The most common clinical manifestation was fever (58.7%). While most patients (78.8%) had asymptomatic/mild disease, the disease severity was moderate in 9.2% and severe and critical in 4.4% and 7.6%, respectively. The overall mortality was 10.9% (n: 20). Deaths were attributable to COVID-19 in nine (4.9%) patients. Multivariate analysis revealed that lower respiratory tract disease (LRTD) (OR, 23.20, p: .001) and lymphopenia at diagnosis (OR, 5.21, p: .006) were risk factors for ICU admission and that HSCT from a mismatched donor (OR, 54.04, p: .028), multisystem inflammatory syndrome in children (MIS-C) (OR, 31.07, p: .003), and LRTD (OR, 10.11, p: .035) were associated with a higher risk for COVID-19-related mortality. CONCLUSION: While COVID-19 is mostly asymptomatic or mild in pediatric transplant recipients, it can cause ICU admission in those with LRTD or lymphopenia at diagnosis and may be more fatal in those who are transplanted from a mismatched donor and those who develop MIS-C or LRTD.

Acute complications observed during intensive chemotherapy in pediatric patients with acute lymphoblastic leukemia: Single-center experience.

OBJECTIVE: In childhood acute lymphoblastic leukemia (ALL), very promising results were obtained thanks to the developments in treatment strategies in recent years. However, acute complications during treatment continue to be the important causes of mortality and morbidity. In this study, acute complications that develop during the treatment of ALL in childhood were evaluated. METHODS: Medical records of 47 patients treated according to (ALL Intercontinental Berlin-Frankfurt-Münster) 2009 protocol between 2016 and 2021 were evaluated retrospectively. RESULTS: Of 47 patients, 28 (59.6%) were male and 19 (40.4%) were female. The mean age at diagnosis was 5.9±4.2 years. Forty-four patients (93.6%) were pre-B cell ALL, 3 patients (6.4%) were pre-T cell ALL. Of 47 patients, 9 (19.1%) were high risk, 32 (68.1%) were intermediate risk, and 6 (12.8%) were standard risk. Acute complications developed in 38 patients (80.8%). Among these complications, infectious complications are the most common and these were followed by gastrointestinal complications, drug-related reactions, thrombotic, neurological, and endocrine/metabolic complications, respectively. CONCLUSION: In terms of complications that may develop, the threshold of suspicion should be kept low, and patients should be treated with the same medical team in fully equipped centers with a multidisciplinary approach. Inpatient treatment strategies should be applied especially in the early stages of treatment. The importance of inpatient treatment strategy, especially in the early stages of treatment, is emphasized.

Any Concern About Delays in the Diagnosis of Childhood Cancers During the COVID-19 Pandemic?

OBJECTIVE: The lockdown precautions during the COVID-19 pandemic led to concerns about the delayed diagnosis of malignancies. This study aimed to compare the duration of complaints at home and the presence of metastasis at diagnosis during the pre-pandemic and pandemic period in children with cancer. MATERIALS AND METHODS: All children diagnosed with cancer and followed up in our clinic between 2017 and 2022 were included. Patients with a diagnosis of acute/chronic leukemia were excluded. Age, gender, cancer type, duration of complaints, and presence of metastasis at diagnosis of the children were recorded. The duration of complaints and presence of metastasis at diagnosis were compared statistically before and after March 11, 2020, the start point of the COVID-19 pandemic in our country. RESULTS: A total of 161 patients diagnosed with cancer were analyzed retrospectively; 61% of patients were males and 39% were females. These patients were diagnosed with brain tumors (23.6%), lymphomas (23%), neuroblastoma (13.7%), rhabdomyosarcomas (10.6%), Ewing's sarcoma (4.3%), osteosarcoma (3.7%), Wilm's tumor (3.7%), and germ cell tumors (3.1%). The duration of complaint was longer during the pandemic than before the pandemic (median: 45 days vs. 30 days) (P < .05). The presence of metastases at diagnosis was 45.3% in the prepandemic period, while it was 40% during the pandemic with no statistical difference (P > .5). CONCLUSION: We concluded that the duration of complaint before diagnosis was longer during the pandemic, while this delay did not affect the metastasis rate at diagnosis in children with cancer. The high rates of distant metastases in newly diagnosed patients both before and during the pandemic suggest that more studies are needed to diagnose these patients earlier.

How do the threshold values used in the decision on red blood cell and platelet transfusions comply with the guidelines?

OBJECTIVE: Blood transfusion is life-saving medical practice with significant risks. National and international guidelines have been established for indications related to blood use and threshold values for transfusions. In this study, we aimed to determine the erythrocyte and thrombocyte transfusion rates in surgical, internal, and emergency clinics in our hospital and to compare the threshold values before erythrocyte and platelet (PLT) transfusion among the clinics. METHODS: Red blood cell (RBC) and PLT transfusions in our hospital between January 2019 and June 2019 were retrospectively analyzed. Clinics were divided into three groups: surgical clinics, internal clinics, and emergency clinic. Demographic characteristics, pre-transfusion hemoglobin (Hb), and PLT values of patients were recorded. Data were analyzed statistically. RESULTS: During the 6-month study period, 5179 patients were transfused in 24,924 patients and the transfusion rate was 21%. In this period, a total of 14,518 units of blood products including 8369 units RBC suspension and 1390 units PLT suspension were transfused. The mean age of the patient was 50.32±28.88 years and the female/male ratio was 1.11. The most RBC transfusions were performed in the general internal medicine service in internal clinics and gynecology in surgical clinics. The most PLT transfusions were performed in the general medicine service in internal clinics and pediatric cardiovascular surgery in surgical clinics. ES transfusions were performed in the emergency medicine clinic with the lowest mean Hb value (Hb: 8.07±1.84 g/dl) and in the surgical clinics with the highest mean Hb value (Hb: 9.29±1.46 g/dl). TS transfusions were performed in internal clinics with the lowest mean PLT value (PLT: 44030±44075/mm3), while the highest mean PLT value (PLT: 97140±75782/mm3) was performed in surgical clinics. CONCLUSION: It was observed that threshold values in particular for PLT transfusions in our hospital were above the guideline recommendations. Our results suggest that the knowledge level of physicians about transfusion limits and practices should be increased.

Use of granulocyte transfusion in early period in life-threatening infections of pediatric hematology and oncology patients: A single-center experience.

Despite all the developments in medicine, infections continue to be one of the most important causes of mortality in pediatric hematology and oncology patients. The more severe the degree of neutropenia develops after intensive chemotherapy in cancer patients, and the longer the neutropenia duration, the higher the risk of infection. Granulocyte transfusion (GT) is used as supportive therapy in cases where the bone marrow needs time to recover in invasive bacterial or fungal infections along with severe neutropenia. The patients who had granulocyte transfusions in our clinic between June 2019 and June 2020 were reviewed retrospectively. A total of 15 units of granulocyte concentrate were used in 11 febrile neutropenia attacks of 9 patients. The demographic characteristics of the patients and features belonging to the period of GT were recorded. In our study, the clinical response rate after GT was 90.9 %, while the hematological response rate was 40 %. Most of the patients were treated succesfully, the mortality rate was 9%. We think that the most critical factor for success with GTs is determining the neutropenic patient in particular with a combination of high-risk malignancy and acute life-threatening infection for using GT. Also, early use of GT in those patients who do not recover despite appropriate antimicrobial and supportive treatment may contribute to improvement of the clinical conditon in a shorter period of time and reduction of repeated GTs.

A Very Rare Type of Leukemia in a Young Pediatric Patient Treated With Hematopoietic Stem Cell Transplantation: Blastic Plasmacytoid Dendritic Cell Neoplasm.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a newly identified, very rare, highly aggressive hematopoietic neoplasm, primarily found in elderly males. They typically present in the form of skin involvement with a high frequency of lymph node and bone marrow involvement. BPDCN has a very poor prognosis, with no consensus on a widely accepted treatment modality. Here we present a very young patient with BPDCN, who presented with generalized lymphadenopathy, skin involvement, and leukemic blasts in the bone marrow. She was treated with high-risk acute lymphocytic leukemia protocol, followed by allogeneic hematopoietic stem-cell transplantation, and has been in clinical remission for 12 months.

Association of CYP3A5 Expression and Vincristine Neurotoxicity in Pediatric Malignancies in Turkish Population.

Vincristine is a widely used chemotherapeutic agent in the treatment of childhood malignancies. Neuropathy is the most common adverse effect. CYP3A4 and CYP3A5 enzymes of cytochrome p450 enzyme system are responsible in vincristine metabolism. Genetic polymorphism may alter the vincristine metabolism and the neurotoxicity rate. In this study, distribution of CYP3A5 alleles among Turkish children with malignancies, relation between CYP3A5 genotype and neurotoxicity rates, as well as severity and duration of neuropathy and total vincristine doses were investigated. Patient group consisted of 115 patients (age, 1 to 17 y) with acute lymphoblastic leukemia and solid tumors, who were treated with vincristine consisting chemotherapy protocols. Control group consisted of 50 children without any neurological symptom or disorders. All patient files were reviewed for presence and severeness of neurotoxicity symptoms. Blood samples were obtained and CYP3A5 genotypes were analyzed. Neurotoxicity occurred in 20.8% of patients. Although it was found to occur more frequently after 4 doses of vincristine, and rates were higher in the low-dose vincristine group suggesting other contributing factors. Although neurotoxicity rate in the CYP3A5*1/*3 genotype was 17.6%, it was 21.6% in the CYP3A5*3/*3 genotype and the difference was not statistically significant (P<0.05). This study suggested that vincristine-related neurotoxicity is dose-independent and genotype is not the only causative factor in the occurrence of neurotoxicity in these patients.

Multisystem langerhans cell histiocytosis with thymic involvement diagnosed with anterior mediastinal mass in a 2-month-old boy.

Thymus gland involvement in Langerhans cell histiocytosis (LCH) is usually part of multi-system disease and may be more common than previously recognized. However, thymic involvement causing an anterior mediastinal mass is an extremely rare presentation of multisystem LCH. Here we report a 2-month-old-boy admitted to hospital with a giant anterior mediastinal mass with multisystem LCH involving the thymus, lungs, liver and skin. The differential diagnosis of mediastinal mass in children should also include LCH, especially multisystem disease. LCH should also be kept in mind in the differential diagnosis of skin lesions in infants, even if spontaneous regression occurs.

Imaging features of Burkitt lymphoma in pediatric patients.

Burkitt lymphoma is an aggressive and rapidly growing tumor that is curable and highly sensitive to chemotherapy. It can affect almost every tissue in the body, producing various clinical presentations and imaging appearances, according to the predilection of the different subtypes for certain sites. Awareness of its diagnostically specific imaging appearances plays an important role in rapid detection and treatment. In this pictorial review, we aimed to identify the most common imaging features of Burkitt lymphoma in pediatric patients.

High-risk ALK negative anaplastic large-cell lymphoma presenting with hypereosinophilic syndrome in a 2.5-year-old child.

The hypereosinophilic syndromes (HES) are characterized by prolonged nonreactive peripheral blood hypereosinophilia with tissue damage. The lymphocytic HES variant can precede malignant clonal T-cell disease in adults but it is extremely rare to be the presenting feature of lymphomas in children. Here we present a 2.5-year-old boy with HES and mediastinal T-cell anaplastic lymphoma kinase (ALK) negative systemic anaplastic large-cell lymphoma. Mature and immature eosinophils without blasts were shown on bone marrow aspiration while biopsy revealed malignant infiltration. The patient responded well to initial corticosteroid therapy, but high-risk features make a challenge of finding the cure in this extremely rare case.

Wilms' tumor associated with vertebral anomalies.

The association of Wilms tumor (WT) and vertebral disorders, such as hemivertebrae or fusion anomalies, have been described in literature. Here, we report a rare association of butterfly T3, T8 vertebrae and a T2, T7 hemivertebrae in a patient with WT, determined during initial examinations of tumoral extension. In patients with WT, investigation of vertebral malformations should be a part of diagnostic work-up.