B-NHL Cases in a Tertiary Pediatric Hematology-Oncology Department: A 20-Year Retrospective Cohort Study.

Non-Hodgkin lymphoma (NHL) is among the five most common pediatric cancer diagnoses in children and adolescents and consists of a heterogeneous group of lymphoid tissue malignancies -with B-cell-derived NHL accounting for nearly 80% of cases. Novel and high-throughput diagnostic tools have significantly increased our understanding of B-NHL biology and molecular pathogenesis, leading to new NHL classifications and treatment options. This retrospective cohort study investigated 17 cases of both mature B-cell NHL (Burkitt lymphoma or BL; Diffuse large B-cell lymphoma or DLBCL; Primary mediastinal large B-cell lymphoma or PMBCL; Follicular lymphoma or FL) and immature B-cell progenitor NHL (B-lymphoblastic lymphoma or BLL) that were treated in a tertiary Pediatric Hematology-Oncology Department during the last 20 years. Modern NHL protocols for children, adolescents, and young adults, along with the addition of rituximab, are safe and efficient (100% overall survival; one relapse). Elevated ESR was more prevalent than elevated LDH. Analyses have focused on immune reconstitution (grade ≥3 infections, lymphocyte and immunoglobulin levels recovery) and body-mass-index changes post-treatment, late effects (in 53% of patients), and the presence of histology markers BCL2, BCL6, CD30, cMYC, and Ki-67%. One patient was diagnosed with a second malignant neoplasm (papillary thyroid cancer).

The Diverse Genomic Landscape of Diamond-Blackfan Anemia: Two Novel Variants and a Mini-Review.

Diamond-Blackfan anemia (DBA) is a ribosomopathy characterized by bone marrow erythroid hypoplasia, which typically presents with severe anemia within the first months of life. DBA is typically attributed to a heterozygous mutation in a ribosomal protein (RP) gene along with a defect in the ribosomal RNA (rRNA) maturation or levels. Besides classic DBA, DBA-like disease has been described with variations in 16 genes (primarily in GATA1, followed by ADA2 alias CECR1, HEATR3, and TSR2). To date, more than a thousand variants have been reported in RP genes. Splice variants represent 6% of identifiable genetic defects in DBA, while their prevalence is 14.3% when focusing on pathogenic and likely pathogenic (P/LP) variants, thus highlighting the impact of such alterations in RP translation and, subsequently, in ribosome levels. We hereby present two cases with novel pathogenic splice variants in RPS17 and RPS26. Associations of DBA-related variants with specific phenotypic features and malignancies and the molecular consequences of pathogenic variations for each DBA-related gene are discussed. The determinants of the spontaneous remission, cancer development, variable expression of the same variants between families, and selectivity of RP defects towards the erythroid lineage remain to be elucidated.

Exophiala dermatitidis Central Line-Associated Bloodstream Infection in a Child with Ewing's Sarcoma: Case Report and Literature Review on Paediatric Infections.

Exophiala dermatitidis is a dematiaceous, ubiquitous, dimorphic fungus, which can cause a wide range of invasive diseases in both immunocompromised and immunocompetent hosts. Bloodstream infections due to E. dermatitidis are rarely encountered in clinical practice, especially in pediatric patients. We describe a case of central line-associated bloodstream infection due to E. dermatitidis in a 4.5-year-old boy with Ewing's sarcoma. The fungus was isolated from blood specimens taken from the Hickman line. The isolate was identified by its phenotypic characteristics, by MALDI-TOF and by using molecular methods. The infection was successfully treated with voriconazole and catheter removal. The literature was also reviewed on pediatric infections caused by E. dermatitidis, focusing on clinical manifestations and challenges associated with diagnosis and management.

Role of CXCL12, TP53 and CYP1A1 gene polymorphisms in susceptibility to pediatric acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is the most common type of childhood leukemia and represents one third of all pediatric malignancies. Epidemiological studies have shown that various genetic factors play a crucial role in leukemogenesis. Recent genetic association studies on cancer risk have focused on the effects of single-nucleotide polymorphisms (SNPs) in genes that regulate inflammation and tumor suppression, such as chemokines, TP53 and cytochrome P450s (CYPs). Genetic polymorphisms in the 3' untranslated region of the C-X-C motif chemokine ligand 12 (CXCL12; rs1801157) and TP53 (rs1042522) genes have been suggested to influence the risk of ALL in children, while other studies have indicated an association between the CYP1 subfamily A member 1 (CYP1A1)*2C (rs1048943) allele and leukemia risk. The aim of the present study was to investigate the possible association of rs1801157 (CXCL12), rs1042522 (TP53) and rs1048943 (CYP1A1*2C) SNPs with an increased susceptibility of developing ALL. These SNPs were analyzed in 86 children or adolescent patients with ALL and 125 control subjects by PCR-restriction fragment length polymorphism and allelic-specific chain reaction techniques. A higher frequency of CYP1A1*2C heterozygotes and TP53 rare homozygotes, which include the proline (Pro)/Pro genotype, was observed among children with ALL and control subjects, whereas no significant differences were observed for the CXCL12 SNP. Furthermore, the analysis of various allelic combinations of the aforementioned gene polymorphisms demonstrated a markedly increased risk of developing ALL in children. In conclusion, the present study demonstrated that there was a strong association between CYP1A1*2C heterozygotes, as well as the TP53 Pro/Pro genotype, and an increased susceptibility for pediatric ALL in Caucasians.

Diagnostic Capacity for Invasive Fungal Infections in the Greek Paediatric Haematology-Oncology Units: Report from the Infection Working Group of the Hellenic Society of Paediatric Haematology-Oncology.

An audit based on a specific questionnaire was attempted, in order to investigate the mycology laboratory diagnostic capacity for invasive fungal diseases (IFDs) in Greek Paediatric Haematology-Oncology departments/units. The study provided the relevant information for the years 2019 and 2020 and included data from all units, concerning culture-based methods and direct microscopy, phenotypic and molecular identification, sensitivity testing, serology and molecular diagnosis, as well as therapeutic drug monitoring. The target was mostly to reveal the level of laboratory coverage for hospitalised paediatric patients, independently of the possibility of performing the tests in the host hospital, or otherwise to refer the specimens elsewhere. In total, the current study demonstrated that the most important facilities and services regarding the IFD diagnostics for paediatric haematology-oncology patients in Greece are available and relatively easily accessible, with a reasonable turnaround time. Acting as an initial registry for further improvements, the audit can serve as a valuable approach to the actual situation and future perspectives. A national clinical mycology network under the auspices of the relevant scientific societies will probably facilitate collaboration between all the departments (clinical and laboratory) involved in invasive fungal infections and provide an easier approach to any necessary test for any hospitalised patient.

Cerebrospinal fluid and intraoperative squash cytology of childhood ependymoma.

Ependymomas are glial neoplasms of central nervous system originated from the ependymal lining of the brain ventricles and spinal cord central canal, and rarely exfoliated into cerebrospinal fluid (CSF). In this case we report the cytomorphological and immunocytomorphological features of ependymoma in CSF and intraoperative squash preparations, confirmed by histology. Case report. The patient  was a nineteen months old female presented at the University hospital of Heraklion, Crete, in a hemicoma, and was intubated. Computed tomography, scanning and magnetic resonance imaging (MRI), were performed and a mass in the posterior fossa was found. A sample of cerebrospinal fluid (CSF) was sent for cytologic evaluation. A diagnosis of ependymoma was rendered, followed by tumor resection, during which intraoperative squash smears for cytologic interpretation were obtained. Cytological consultation disclosed a grade II ependymoma (WHO grade II), with focally anaplastic features (WHO grade III).

Candidemia in Children with Malignancies: Report from the Infection Working Group of the Hellenic Society of Pediatric Hematology-Oncology.

Candidemia is an important cause of morbidity and mortality especially in immunocompromised and hospitalized patients. We retrospectively collected data of candidemia cases that occurred in the seven Hematology-Oncology Departments/Units of Greece and the Stem Cell Transplant Unit between 2015 and 2019. In total, 19 episodes of candidemia in 19 patients were recorded. The majority of the patients (78.9%) had at least one risk factor for candidemia. The most frequent risk factors associated with candidemia observed in our patients were prolonged duration of hospitalization (30 days, range 1-141), presence of a central venous catheter at diagnosis of candidemia (73.7%) and antibiotics use during the last two weeks (84.2%). Candida parapsilosis was the most common species isolated accounting for 42.1%, followed by C. albicans (26.3%) and C. famata (15.8%). Nearly all of the patients (84.2%) received antifungal monotherapy with liposomal amphotericin B or echinocandins. The central venous catheter was removed in 78.6% of patients and the median time between the first positive blood culture and catheter removal was 3 days (range 1-9). Mortality at 28 days was 26.3%. In conclusion, a predominance of non-albicans species was observed in our study in conformity with the global trend.

Voriconazole Antifungal Prophylaxis in Children With Malignancies: A Nationwide Study.

BACKGROUND: Antifungal prophylaxis (AFP) is recommended in at-risk hematology-oncology patients. We evaluated the safety of AFP with voriconazole (VRC) in pediatric hematology/oncology patients. MATERIALS AND METHODS: A retrospective study of VRC AFP in children with malignancies hospitalized in all 7 Greek pediatric hematology/oncology centers during 2008 to 2012 was conducted. Patients' demographics, outcome, and adverse event (AE) data were recorded. RESULTS: Four hundred twenty-nine VRC AFP courses in 249 patients (median age 6 y, 55% boys) were studied. The most common underlying diseases were acute lymphoblastic leukemia (51%), non Hodgkin lymphoma (8.6%), and acute myeloid leukemia (7.7%). The median number of VRC courses per patient was 1.7, whereas the median VRC dose was 7 mg/kg (range, 5 to 7 mg/kg) every 12 hours. During the last 2 weeks before AFP, 51% of the patients had received corticosteroids, 43% suffered from severe neutropenia, and 17.3% from mucositis. The median duration of VRC AFP was 17 days (range, 1 to 31 d). A single breakthrough fungemia due to Candida glabrata was recorded. Only 1 patient died due to the underlying disease. The most common AEs reported in 70/429 (16.3%) courses with ≥1 AE were elevated liver enzymes (50%), hypokalemia (24.3%), and ophthalmological disorders (14.3%). The median time of AE onset was 5 days (range, 1 to 21 d). Among 70 AEs reported, 38.5%, 48.4%, and 12.8% were of grade I, II, and III, respectively. CONCLUSIONS: VRC prophylaxis in pediatric hematology/oncology patients appears to be well tolerated.

Central line-associated bloodstream infection in childhood malignancy: Single-center experience.

BACKGROUND: Central line-associated bloodstream infection (CLABSI) is a common complication in children with malignancy, often leading to prolonged hospitalization, delay in chemotherapy or catheter removal. This retrospective epidemiological study reviewed 91 children with malignancy over a 5 year period between 2011 and 2015 and analyzed potential risk factors for CLABSI. METHODS: Symptoms, laboratory and microbiology characteristics, subsequent treatment and outcome were recorded and analyzed. All the collected data were processed through SPSS for statistical analysis. RESULTS: Among 40 episodes of CLABSI recorded in 30 patients, the rate of CLABSI was estimated as 2.62 episodes per 1,000 days of central venous catheter (CVC) carriage. Most of the bacterial pathogens isolated in CLABSI episodes were Gram positive, including different strains of staphylococci, while Gram-negative bacteria were involved in 30% of episodes. Invasive mycosis was isolated in 7.5% of episodes, accounting for the highest catheter removal rate. Intensive chemotherapy and prolonged hospitalization proved to be independent risk factors for CVC infection. In children with neutropenia, the risk for CLABSI was also fourfold greater (P = 0.001). Children with leukemia had a fivefold greater risk for CLABSI (P = 0.005). Finally, although 36% of patients received antibiotic lock therapy, in 15% of these patients catheter replacement could not be avoided due to persistent serious infection. CONCLUSIONS: Younger age, neutropenia, hematologic malignancy and longer catheterization are important risk factors for CLABSI, but further research is required for the prevention of catheter-related infection in children with malignancy.

Multifocal bone and bone marrow lesions in children - MRI findings.

Polyostotic bone and bone marrow lesions in children may be due to various disorders. Radiographically, lytic lesions may become apparent after loss of more than 50% of the bone mineral content. Scintigraphy requires osteoblastic activity and is not specific. MRI may significantly contribute to the correct diagnosis and management. Accurate interpretation of MRI examinations requires understanding of the normal conversion pattern of bone marrow in childhood and of the appearances of red marrow rests and hyperplasia. Differential diagnosis is wide: Malignancies include metastases, multifocal primary sarcomas and hematological diseases. Benign entities include benign tumors and tumor-like lesions, histiocytosis, infectious and inflammatory diseases, multiple stress fractures/reactions and bone infarcts/ischemia.

Idiopathic thrombocytopenic purpura in childhood: twenty years of experience in a single center.

BACKGROUND: Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder with a variable clinical course. METHODS: A retrospective analysis was carried out of ITP patients presenting to a pediatric hematology-oncology department during a period of 20 years, with a focus on treatment and outcome. RESULTS: One hundred and twenty-four cases were recorded (mean patient age, 8.4 years). Forty-nine children (39.5%) had platelet counts <10,000/µL at diagnosis. No episode of severe bleeding was observed. Peak incidence was observed during spring and summer. Respiratory infections proceeded in 58% of cases. Treatment consisted of i.v. immunoglobulin (IVIG) in 93 children at four dosing schedules. Sixteen children received corticosteroids, 10 children received anti-D immunoglobulin and 14 received no treatment. Recovery was observed in 67% of children on IVIG and in 50% on anti-D globulin. Eight patients did not respond initially and received corticosteroids. Three children with refractory thrombocytopenia received anti-CD20 (rituximab). Fourteen children (11%) had persistent/chronic disease. In 10 of them recovery was observed in 13 months-8 years. Splenectomy was performed in six children with resistant/chronic disease. CONCLUSION: ITP has a benign course in the majority of cases. Anti-D globulin can effectively be used as an alternative first-line treatment. Rituximab can successfully be used in refractory cases, while splenectomy has currently limited indications.

Multiple injuries in vital organs in a child from a gunshot: a case report.

INTRODUCTION: Many people in rural and urban areas own a gun legally or illegally. It is a social phenomenon that apart from the adults, the children become familiar with the guns in early age. CASE PRESENTATION: A nine year old boy was shot by accident by his uncle, who was cleaning his gun (carbine) close to where the child was playing. More than 200 pellets were counted in the boy's x-rays. The boy was hospitalised in pediatric intensive care unit with many injuries in thorax, abdomen, and limbs, clearly shown by the x-rays. He developed multiple injuries in lungs and liver, bilateral haemothorax and pneumothorax, subcutaneous emphysema, injury of pericardium, perirenal hematoma, choloperitoneum, injuries in the intestine and in the limbs. Initial level of lead in the boy's body was measured as a reference value. Thereafter, frequent monitoring for lead levels was scheduled to prevent a potential lead poisoning from the pellets' absorption. After the appropriate treatment the boy left the hospital in a month in good health. CONCLUSION: The consequences from gun use in places where children are exposed could be fatal. The appropriate co-operation of different medical sub-specialities in Pediatrics and the presence of pediatric intensive care unit can save the life of a child with multiple injuries.

Moderate intravenous sedation with fentanyl and midazolam for invasive procedures in children with acute lymphoblastic leukemia.

Data were collected prospectively on 100 consecutive invasive procedures, that is, lumbar and bone marrow punctures (alone or in combination), in 16 patients less than 21 years of age with acute lymphoblastic leukemia (ALL). Efficacy of sedation and the need for restraint were graded according to 2 multiple-point scales. All invasive procedures were successfully performed. Oxygen by face mask was needed in 5 cases, whereas no patient required sedation reversal; 92% of the time, the patient was calm, cooperative, and responding to verbal commands, whereas in 97 procedures, there was no or only minimal patient movement that did not interfere with the completion of the procedure. Inpatient administration of midazolam and fentanyl by trained pediatric providers is safe and effective for invasive procedures in children and adolescents with ALL.

Primary hepatic Burkitt lymphoma.

Primary hepatic lymphomas are exceedingly rare in children, with less than a dozen cases described to date. The authors present an 8.5-year-old boy with Burkitt lymphoma of the liver who had isolated multifocal liver lesions that exhibited a multilayered progressive enhancing pattern on MRI. Diagnosis was achieved after laparotomy and incisional biopsy that failed to detect disease outside the liver. The patient received short, intensive multiagent chemotherapy. He is currently well 22 months after the end of chemotherapy. This case illustrates that clinical judgment in conjunction with unusual imaging findings may contribute to the diagnosis of common tumors in rare locations.

Spectral characteristics of acute lymphoblastic leukemia in childhood.

Although the differentiation and classification of acute leukemia are based upon cytochemical features as well as immunologic, cytogenetic, and molecular characteristics, in many cases the morphological distinction of normal lymphocytes from lymphoblasts of acute lymphoblastic leukemia (ALL) is difficult using light microscopy. In this study the distinction between normal lymphocytes and lymphoblasts of childhood ALL is proposed using their spectral characteristics. The method has been based upon the analysis and classification of optical absorption characteristics of the bone marrow cells. Spectral microscopy system is capable of capturing a great number of narrow-band images, in the wide spectral range of the optical spectrum. The analysis showed statistically significant difference (P < 0.0001) between normal lymphocytes and lymphoblasts as far as it concerns the detection, identification and mapping of their spectral absorption characteristics. Our results suggest the potential of spectral imaging as a new method for the distinction of lymphocytes from lymphoblasts in cases that with the light microscope, the morphologic differences are not visible in the bone marrow smears at diagnosis or the follow up of the children with ALL.