Spanish registry of hemoglobinopathies and rare anemias (REHem-AR): demographics, complications, and management of patients with ß-thalassemia.

INTRODUCTION: The increase in the number of patients with hemoglobinopathies in Europe in recent decades highlights the need for more detailed epidemiological information in Spain. To fulfil this need, the Spanish Society of Pediatric Hematology and Oncology (SEHOP) sponsored the creation of a national registry of hemoglobinopathies known as REHem-AR (Spanish Registry of Hemoglobinopathies and Rare Anemias). Data from the transfusion-dependent (TDT) and non-transfusion-dependent (NTDT) ß-thalassemia cohorts are described and analyzed. METHODS: We performed an observational, multicenter, and ambispective study, which included patients of any age with TDT and NTDT, registered up to December 31, 2021. RESULTS: Among the 1741 patients included, 168 cases of thalassemia were identified (103 TDT and 65 NTDT-patients). Survival at 18 years was 93% for TDT and 100% for NTDT. Regarding management, 80 patients with TDT (77.7%) and 23 patients with NTDT (35.4%) started chelation treatment during follow-up, with deferasirox being the most widely used. A total of 76 patients within the TDT cohort presented at least 1 complication (73.8%), the most frequent being hemosiderosis and osteopenia-osteoporosis. Comparison of both cohorts revealed significant differences in the diagnosis of hepatic hemosiderosis (p = 0.00024), although these were not observed in the case of cardiac iron overload (p = 0.27). DISCUSSION: Our registry enabled us to describe the management of ß thalassemia in Spain and to analyze the morbidity and mortality of the cohorts of patients with TDT and NTDT. Complications related to iron overload in TDT and NTDT account for most of the morbidity and mortality of the disease, which is associated with a considerable social, psychological, and economic impact, although cardiac, osteopathy and endocrinological complications requiring more attention. The convenience and simplicity of online registries make it possible to homogenize variables and periodically update data, thus providing valuable information on these diseases.

Madrid Newborn Sickle Cell Disease Cohort: clinical outcomes, stroke prevention and survival.

In May 2003, Madrid established the universal newborn screening (NBS) for sickle cell disease (SCD). However, there are no studies resembling the evolution of a SCD neonate cohort followed according to national guidelines in Spain. The aim of this study is to describe the morbimortality and the stroke prevention programme in patients diagnosed by SCD NBS in Madrid. This is a multicentre, observational, prospective cohort study between 2003 and 2018; 187 patients diagnosed with SCD were included (151 HbSS, 6 HbSß0, 27 HbSC, 3 HbSß +), and median follow-up was 5.2 years (0.03-14.9). There were 5 deaths: 2 related to SCD in patients with severe genotype (HbSS/HbSß0). Overall survival reached 95% and SCD-related survival 96.8%. The most frequent events were fever without focus, vaso-occlusive crises and acute chest syndromes. Eight strokes occurred in 5 patients which led to a 90.7% stroke-free survival in severe genotype patients (first stroke rate, 0.54 per 100 patient-years). Transcranial Doppler (TCD) was performed in 95% of eligible patients; 75% of children with pathological TCD remained stroke-free. Regarding HbSS/HbSß0 patients, 50.1% received hydroxyurea and 9.5% haematopoietic stem cell transplantation. This study reflects the evolution of Madrid SCD cohort and provides morbimortality data similar to other developed countries.

Use of Monoclonal Antibodies in a Pediatric Patient With Severe Combined Immunodeficiency and Persistent SARS-CoV-2 Infection.

We describe the use of monoclonal antibodies for the treatment of persistent SARS-CoV-2 infection in a pediatric patient with severe combined immunodeficiency who required urgent stem cell transplantation to cure his disease.

[Recurrent Cupriavidus Pauculus catheter-related bacteremia]. / Bacteriemia recurrente relacionada con catéter por Cupriavidus pauculus.

Catheter-related bacteriemia by Cupriavidus spp. is a rare condition with very few cases reported in the literature. Most of them occurred in immunocompromised patients. OBJECTIVE: To report a case of recurrent catheter-related bacteriemia by Cupriavidus pauculus in an immunocompromised infant in order to analyze possible therapeutic options, especially in relation to the need or not for central venous catheter (CVC) removal. CLINICAL CASE: 22-month-old infant with B-cell acute lymphoblas tic leukemia (ALL) in reinduction phase, CVC carrier. He presented to the Emergency Room with fever without focus on examination. Blood tests were performed (without increase of acute phase reactants) and differential blood cultures (peripheral and CVC). He was hospitalized and empirical antibiotic therapy was started with intravenous fourth-generation cephalosporin (cefepime). After 24 hours, blood cultures were positive for Cupriavidus pauculus, growing first in the CVC culture. We maintained cefepime, adding catheter lock therapy with ciprofloxacin. Afterward, the infection was resolved, allowing us to keep the CVC. Seven months later, in the context of fever, Cupriavidus pauculus was again identified in CVC blood culture. We decided this time to remove the catheter, in addition to the administration of intravenous cefepime. The patient has not presented new episodes nine months after de removal of the CVC. CONCLUSION: Catheter-related bacteremia by Cupriavidus is a rare condition in children that usually occurs in immunocompromised patients. Catheter lock therapy associated with systemic antibiotics could be a safe option in patients with difficult CVC re moval. However, if persistent colonization of the CVC is suspected, it may be necessary to remove it.

Venous thromboembolism in pediatric patients with acute lymphoblastic leukemia under chemotherapy treatment. Risk factors and usefulness of thromboprophylaxis. Results of LAL-SEHOP-PETHEMA-2013.

INTRODUCTION: Symptomatic venous thromboembolism (VTE) is diagnosed in 3%-14% of patients during pediatric acute lymphoblastic leukemia (ALL) therapy. There are well-known risk factors, but the role of others as inherited thrombophilia is still controversial. Prophylaxis with low molecular weight heparin (LMWH) has been described, but its use is not globally accepted. METHODS: A retrospective multicentric study in ALL patients 1-18 years old following SEHOP-PETHEMA-2013 treatment guideline was performed to evaluate VTE rate, anticoagulant treatment, outcome, risk factors, and safety and usefulness of LMWH administration as primary thromboprophylaxis in children with inherited thrombophilia. RESULTS: A total of 652 patients were included in the study. VTE incidence was 8.7%. Most of the cases occurred during induction therapy associated with central venous catheter. Univariant analysis showed that family history of thrombosis, presence of mediastinal mass, high-risk treatment group, and inherited thrombophilia were statistically significant risk factors. LMWH administration seemed to decrease VTE rate in patients with inherited thrombophilia and those with T-cell ALL phenotype. CONCLUSION: Most of the VTE cases occurred in patients without inherited thrombophilia, but when it is present, the VTE risk is higher. LMWH administration was useful to decrease VTE in these patients.

Interleukin 6 as a marker of severe bacterial infection in children with sickle cell disease and fever: a case-control study.

BACKGROUND: Etiological diagnosis of fever in children with sickle cell disease (SCD) is often challenging. The aim of this study was to analyze the pattern of inflammatory biomarkers in SCD febrile children and controls, in order to determine predictors of severe bacterial infection (SBI). METHODS: A prospective, case-control study was carried out during 3 years, including patients younger than 18 years with SCD and fever (cases) and asymptomatic steady-state SCD children (controls). Clinical characteristics and laboratory parameters, including 10 serum proinflammatory cytokines (IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-17a, IFN-γ and TNF-α) and comparisons among study subgroups were analyzed. RESULTS: A total of 137 patients (79 cases and 58 controls) were included in the study; 78.5% males, median age 4.1 (1.7-7.5) years. Four cases were diagnosed with SBI, 41 viral infection (VI), 33 no proven infection (NPI) and 1 bacterial-viral coinfection (the latter excluded from the subanalyses). IL-6 was significantly higher in patients with SBI than in patients with VI or NPI (163 vs 0.7 vs 0.7 pg/ml, p < 0.001), and undetectable in all controls. The rest of the cytokines analyzed did not show any significant difference. The optimal cut-off value of IL-6 for the diagnosis of SBI was 125 pg/mL, with high PPV and NPV (PPV of 100% for a prevalence rate of 5, 10 and 15% and NPV of 98.7%, 97.3% and 95.8% for those prevalences rates, respectively). CONCLUSION: We found that IL-6 (with a cut-off value of 125 pg/ml) was an optimal marker for SBI in this cohort of febrile SCD children, with high PPV and NPV. Therefore, given its rapid elevation, IL-6 may be useful to early discriminate SCD children at risk of SBI, in order to guide their management.

Case Report: Severe ARDS in a Pediatric Hematopoietic Stem-Cell Transplantation Recipient Caused by Disseminated Toxoplasmosis.

Toxoplasma gondii infection is a severe complication of hematopoietic stem-cell transplantation (HSCT) recipients that can remain unnoticed without a high clinical suspicion. We present the case of a 6-year-old patient with acute lymphoblastic leukemia and HSCT recipient who was admitted to the Pediatric Intensive Care Unit (PICU) on post-transplantation day +39 with fever, hypotension, severe respiratory distress and appearance of a lumbar subcutaneous node. She developed severe Acute Respiratory Distress Syndrome (ARDS) and underwent endotracheal intubation and early mechanical ventilation. Subsequently, she required prone ventilation, inhaled nitric oxide therapy and high-frequency oscillatory ventilation (HFOV). An etiologic study was performed, being blood, urine, bronchoalveolar lavage and biopsy of the subcutaneous node positive for Toxoplasma gondii by Polymerase Chain Reaction (PCR). Diagnosis of disseminated toxoplasmosis was established and treatment with pyrimethamine, sulfadiazine and folinic acid started. The patient showed clinical improvement, allowing weaning of mechanical ventilation and transfer to the hospitalization ward after 40 days in the PICU. It is important to consider toxoplasmosis infection in immunocompromised patients with sepsis and, in cases of severe respiratory distress, early mechanical ventilation should be started using the open lung approach. In Toxoplasma IgG positive patients, close monitoring and appropriate anti-infectious prophylaxis is needed after HSCT.

Complications of Central Venous Access Devices in Patients With Sickle Cell Disease and Thalassemia Major.

Pediatric patients with sickle cell disease and thalassemia major present clinical characteristics that could lead to a higher incidence of central venous access devices-associated complications (CVAD-C). With the objective of analyzing the safety of the use of CVAD in these patients, a retrospective review including all pediatric patients with these pathologies who required the implantation of a CVAD between 2004 and 2019 was performed. In all, 54 patients with 100 CVAD (65 totally implantable venous access port with subcutaneous reservoir, 35 single-lumen or double-lumen partially tunneled catheter) were included. During 60,410 days at risk of suffering a CVAD-C, 55 complications (complication rate [CR]/1000 catheter-days at risk=0.91) were reported in 46 CVAD: 19 mechanicals (CR=0.32), 32 infectious (CR=0.53), and 4 thrombotic complications (CR=0.066). Incidence of mechanical and infectious complications was significantly higher in double-lumen partially tunneled catheter than in totally implantable venous access port with subcutaneous reservoir (P<0.001). Lower age at insertion was related with a higher incidence of any complication (odds ratio=0.88/y, P=0.02). Patients who required a stem cell transplantation (31 patients and 65 CVAD) had no significant higher incidences of CVAD-C. In conclusion, our study supports the safety of using CVAD in these patients, with a low incidence of infectious, thrombotic, and mechanical complications.

Bromocriptine for the treatment of postoperative cerebellar mutism syndrome in pediatric patients: Three case reports.

INTRODUCTION: Cerebellar mutism syndrome (CMS) is a common complication after posterior fossa tumor resection. It is characterized by a significant lack or loss of speech. Its biological origin remains unclear and there are no standardized treatments. However, bromocriptine seems to be a possible treatment for this condition. CASE REPORT: In this paper, we present three cases of pediatric patients (4, 5, and 17-year old) who developed CMS after posterior fossa tumor surgery. They were treated with bromocriptine to improve neurological symptoms.Management and outcome: Bromocriptine was started at a low dose and was progressively increased to reach the minimum effective dose. After four months of treatment, a normal and fluid speech was observed in the three patients. No discontinuation due to adverse events were reported. DISCUSSION: Bromocriptine has shown to be an effective and safe treatment for CMS in pediatric patients after posterior fossa tumor resection.

Blinatumomab and inotuzumab for B cell precursor acute lymphoblastic leukaemia in children: a retrospective study from the Leukemia Working Group of the Spanish Society of Pediatric Hematology and Oncology (SEHOP).

Blinatumomab and inotuzumab ozogamycin represent promising alternatives to conventional chemotherapy in acute lymphoblastic leukaemia (ALL). We analysed data from 29 children with ALL treated under compassionate use with blinatumomab, inotuzumab or both. The complete remission (CR) rate in a heavily pretreated population with overt relapse was 47·6%. At earlier stages (first/second CR), both antibodies represented a useful tool to reduce minimal residual disease, and/or avoid further toxic chemotherapy until stem cell transplantation. Six patients developed grade 3 reversible non-haematological toxicity. The 12-month overall survival and event-free survival rates were 50·8 ± 26·4% and 38·9 ± 25·3% with blinatumomab, 45·8 ± 26% and 27·5 ± 25% with inotuzumab.

Detection of Respiratory Viruses in the Clinical Outcome of Children With Fever and Neutropenia.

BACKGROUND: Several evidence-based guidelines for the management of children with febrile neutropenia (FN) have been published, with special focus in bacterial and fungal infections. However, the role of acute respiratory infections caused by respiratory viruses (RV) has not been clearly established. The aim of this study was to evaluate the epidemiology, clinical presentation and outcome of acute respiratory infections in children with FN. METHODS: Patients, <18 years of age admitted to the Pediatric Oncology-Hematology Unit after developing FN between November 2010 and December 2013, were prospectively included in the study. Children were evaluated by clinical examination and laboratory tests. Nasopharyngeal sample was obtained for detection of RV. RESULTS: There was a total of 112 episodes of FN in 73 children admitted to the hospital during a 32-month period. According to disease severity, 33% of the episodes were considered moderate or severe. Rhinovirus was the most frequently detected RV (66.6%; 24/36), followed by parainfluenza. On regard to clinical outcome, RV-infected children developed fewer episodes of moderate or severe FN compared with non-RV infected children (16.7% vs. 33.3%; P = 0.08). CONCLUSIONS: A great proportion of children with FN admitted to a tertiary hospital had a RV isolation. The rate of this RV isolation was significantly higher when a rapid molecular test was used compared with conventional microbiologic methods. Rhinovirus was the most frequently isolated, although its role as an active agent of acute infection was not clear. Children with FN and a RV isolate had a lower rate of severe disease.

Measurable Residual Disease Assessed by Flow-Cytometry Is a Stable Prognostic Factor for Pediatric T-Cell Acute Lymphoblastic Leukemia in Consecutive SEHOP Protocols Whereas the Impact of Oncogenetics Depends on Treatment.

Robust and applicable risk-stratifying genetic factors at diagnosis in pediatric T-cell acute lymphoblastic leukemia (T-ALL) are still lacking, and most protocols rely on measurable residual disease (MRD) assessment. In our study, we aimed to analyze the impact of NOTCH1, FBXW7, PTEN, and RAS mutations, the measurable residual disease (MRD) levels assessed by flow cytometry (FCM-MRD) and other reported risk factors in a Spanish cohort of pediatric T-ALL patients. We included 199 patients treated with SEHOP and PETHEMA consecutive protocols from 1998 to 2019. We observed a better outcome of patients included in the newest SEHOP-PETHEMA-2013 protocol compared to the previous SHOP-2005 cohort. FCM-MRD significantly predicted outcome in both protocols, but the impact at early and late time points differed between protocols. The impact of FCM-MRD at late time points was more evident in SEHOP-PETHEMA 2013, whereas in SHOP-2005 FCM-MRD was predictive of outcome at early time points. Genetics impact was different in SHOP-2005 and SEHOP-PETHEMA-2013 cohorts: NOTCH1 mutations impacted on overall survival only in the SEHOP-PETHEMA-2013 cohort, whereas homozygous deletions of CDKN2A/B had a significantly higher CIR in SHOP-2005 patients. We applied the clinical classification combining oncogenetics, WBC count and MRD levels at the end of induction as previously reported by the FRALLE group. Using this score, we identified different subgroups of patients with statistically different outcome in both Spanish cohorts. In SHOP-2005, the FRALLE classifier identified a subgroup of high-risk patients with poorer survival. In the newest protocol SEHOP-PETHEMA-2013, a very low-risk group of patients with excellent outcome and no relapses was detected, with borderline significance. Overall, FCM-MRD, WBC count and oncogenetics may refine the risk-stratification, helping to design tailored approaches for pediatric T-ALL patients.

[Bone marrow transplant in patients with sickle cell anaemia. Experience in one centre]. / Trasplante de médula ósea en pacientes con anemia falciforme. Experiencia en un centro.

INTRODUCTION: Sickle cell disease (SCD), despite the improvement in the medical management, is still associated with severe morbidity and decreased survival. Allogenic hematopoietic stem cell transplantation (Allo-HSCT) currently provides the only curative therapy. A report is presented on our experience in children with SCD, who underwent Allo-HSCT in a single centre. MATERIAL AND METHOD: A single centre descriptive study was conducted on patients with SCD who underwent a bone marrow transplant from an HLA-identical sibling donor between January 2010 and December 2014. Epidemiological, clinical and analytical parameters were collected with a follow-up to December 2015. Data are presented as frequencies, percentages, and medians (range). RESULTS: Allo-HCST was performed in 11 patients (8 males) with a median age of 7 years (2-13), all of them with comorbidity prior to the HCST. A stable graft was achieved in 10 out of 11 patients, 9 of them with complete donor chimerism, and one patient with stable mixed chimerism after 1 year of allo-HSCT. One patient has secondary graft failure with re-appearance of symptoms associated with SCD on day 180. Complications of Allo-HSCT are: arterial hypertension 7/11, acute renal failure 3/11, CMV reactivation 9/11, neurological complications 4/11 (subarachnoid haemorrhage, seizure), and acute graft versus host disease (aGVHD) of the skin 6/11, one of whom developed grade iv intestinal aGVHD, causing his death (day 51). None of the patients developed chronic GVHD. The overall survival and event-free survival was 90.9% and 81.9%, respectively, with a median follow-up of 3.1 (1-5.7) years. CONCLUSIONS: Allo-HSCT, the only curative therapy, remains associated with morbidity. There was a transplant related mortality in our study, consistent with multicentre studies (1/11), and with aGVHD being the main cause. Other problems still include graft failure (1/11), and neurological complications (4/11), although the permanent sequelae are mild.

DICER1 mutation and tumors associated with a familial tumor predisposition syndrome: practical considerations.

The familial tumor predisposition syndrome known as DICER1-pleuropulmonary blastoma (PPB) or DICER1 tumor predisposition syndrome was first described in 2009, and it involves an increased risk in the occurrence of various tumors, like cystic nephroma and PPB. Here is presented a girl with a cystic nephroma and two cystic lung lesions who was diagnosed years later with the DICER1 gene mutation. This mutation was also found in one of her parents. Thus, the screening for the DICER1 gene mutation may be important in children with certain/multiple tumors and their families.