Cerebral vasculopathy in patients with sickle cell disease and stroke: now you see it, now you don't.

Not available.

Severe Transfusion-Dependent Thalassemia in Compound Heterozygote Palestinian Siblings with Two α-Globin Gene Defects, Hb Taybe D HBA1: C.119_121delCCA Mutation and HBA2: C.*94A > G Mutation.

Alpha and Beta Thalassemia are autosomal recessive anemias that cause significant morbidity and mortality worldwide, especially in the Middle East and North Africa (MENA) region where carrier rates reach up to 50%. We report the case of two siblings of Palestinian origin born who presented to our tertiary healthcare center for the management of severe transfusion dependent hemolytic anemia. Before presentation to our center, the siblings were screened for a-thalassemia using the Alpha-globin StripAssay. They were found to carry the α2 polyA-1 [AATAAA > AATAAG] mutation in the heterozygous form, which was insufficient to make a diagnosis. No pathogenic variants were detected on Sanger sequencing of the HBB gene. Full sequencing of the a-gene revealed compound heterozygous variants (HBA1:c.119_121delCCA and the previously detected HBA2:c.*+94A > G Poly A [A->G]) with trans inheritance. This report highlights the impact of non-deletional mutations on α-globin chain stability. The compound heterozygosity of a rare α-globin chain pathogenic variant with a polyadenylation mutation in the probands leads to clinically severe a-thalassemia. Due to the high carrier status, the identification of rare mutations through routine screening techniques in our populations may be insufficient. Ongoing collaboration among hematologists, medical geneticists, and counselors is crucial for phenotypic-genotypic correlation and assessment of adequate genetic testing schemes.

A novel homozygous mutation in RASGRP1 that predisposes to immune dysregulation and immunodeficiency associated with uncontrolled Epstein-Barr virus-induced B cell proliferation.

BACKGROUND: RASGRP1-deficiency results in an immune dysregulation and immunodeficiency that manifest as autoimmunity, lymphoproliferation, lymphopenia, defective T cell function, and increased incidence of Epstein-Bar Virus infections and lymphomas. OBJECTIVE: To investigate the mechanism of autoimmune hemolytic anemia and infections in a male patient of consanguineous parents from Lebanon. METHODS: Genetic diagnosis was obtained using next generation and Sanger sequencing. Protein expression and phosphorylation were determined by immunoblotting. T and B cell development and function were studied by flow cytometry. Cytokine and immunoglobulin secretions were quantified by enzyme-linked immunosorbent assay. RESULTS: The patient suffered from severe lymphopenia especially affecting the T cell compartment. Genetic analysis revealed a homozygous insertion of adenine at position 1396_1397 in RASGRP1 that abolished protein expression and downstream Ras signaling. T cells from the patient showed severe activation defects resulting in uncontrolled Epstein-Bar Virus-induced B cell proliferation. B cells from the patient were normal. CONCLUSION: This report expands the spectrum of mutations in patients with RasGRP1 deficiency, and provides evidence for the important role RasGRP1 plays in the ability of T cells to control Epstein-Bar Virus-induced B cell proliferation. CLINICAL IMPLICATIONS: Following diagnosis, the patient will be maintained on oral valganciclovir and monitored regularly for Epstein-Bar Virus infections to avoid the development of Epstein-Bar Virus- induced B cell lymphoma. He is also candidate for hematopoietic stem cell transplantation.

Unfolding parental knowledge, attitudes, and beliefs toward palliative care for children with cancer.

BACKGROUND: Parents' views toward pediatric palliative care (PPC) remain underexplored, especially in low/middle-income countries where care relies heavily on families. A better understanding of parents' perspectives would inform strategies to support PPC integration into the care of children with cancer. This multicenter study aimed to examine knowledge, attitudes, and beliefs toward PPC among parents of children with cancer in Lebanon to uncover areas for improvement and determine associated factors. METHODS: Using a quantitative cross-sectional descriptive design, 105 primary caregivers (RR = 95.4%) were recruited during the child's visit to one of three pediatric oncology centers in Lebanon. Data were collected through structured interviews using questionnaire items newly developed or taken from validated tools. Data were analyzed using descriptive statistics, correlational analysis, and multiple linear regression. RESULTS: Only 18/105 participants (17.1%) had heard about PPC and 2% had accurate information about it. When given a brief description, more than 90% endorsed PPC and recommended its integration upon the child's diagnosis. Respectively, "Religious and spiritual engagement" and "Overwhelming negative emotions" were the most cited facilitators and barriers to integrating PPC. Knowledge, attitudes, and beliefs were significantly associated with several demographic and clinical factors such as education level, number of persons living with the child, child's symptom count, and pain score. CONCLUSION: This research is among the very first studies conducted to examine parents' perspectives toward PPC for children with cancer in Lebanon. Study findings inform future directions to promote PPC in limited-resource settings through expanded research, policy, education, and practice initiatives.

Using comprehensive genomic and functional analyses for resolving genotype-phenotype mismatches in children with suspected CMMRD in Lebanon: an IRRDC study.

Constitutional mismatch repair deficiency (CMMRD) is an aggressive and highly penetrant cancer predisposition syndrome. Because of its variable clinical presentation and phenotypical overlap with neurofibromatosis, timely diagnosis remains challenging, especially in countries with limited resources. Since current tests are either difficult to implement or interpret or both we used a novel and relatively inexpensive functional genomic assay (LOGIC) which has been recently reported to have high sensitivity and specificity in diagnosing CMMRD. Here we report the clinical and molecular characteristics of nine patients diagnosed with cancer and suspected to have CMMRD and highlight the challenges with variant interpretation and immunohistochemical analysis that led to an uncertain interpretation of genetic findings in 6 of the 9 patients. Using LOGIC, we were able to confirm the diagnosis of CMMRD in 7 and likely exclude it in 2 patients, resolving ambiguous result interpretation. LOGIC also enabled predictive testing of asymptomatic siblings for early diagnosis and implementation of surveillance. This study highlights the varied manifestations and practical limitations of current diagnostic criteria for CMMRD, and the importance of international collaboration for implementing robust and low-cost functional assays for resolving diagnostic challenges.

Strategic priorities for hematopoietic stem cell transplantation in the EMRO region.

The World Health Organization-designated Eastern Mediterranean region (EMRO) consists of 22 countries in North Africa and Western Asia with a collective population of over 679 million. The area comprises some of the wealthiest countries per capita income and some of the poorest. The population structure is also unique and contrasts with western countries, with a much younger population. The region sits in the heart of the thalassemia belt. Many countries have a significant prevalence of sickle cell disease, and cancer is on the rise in the region. Therefore, the strategic priorities for the growth and development of hematopoietic stem cell transplantation (HSCT) differ from country to country based on resources, healthcare challenges, and prevalent infrastructure. Thirty-one reporting teams to the Eastern Mediterranean Blood and Marrow Transplantation Group have active HSCT programs in 12 countries; allogeneic transplants outnumber autologous transplants, and the proportion of allotransplants for non-malignant conditions is higher in the EMRO region than in Western Europe and North America. The vast majority (99%) of allotransplants are from matched related donors. Matched unrelated donors and other alternate donor transplants are underutilized. The chance of finding a matched related donor for allografts is higher, with a significant chance of finding matched donors among non-sibling related donors. Reasons for relatively lower rates of transplants compared with other countries are multifactorial. Capacity building, development of newer centers, innovative funding, and better utilization of information technology are required to make transplantation as an accessible modality to more patients. Cost-effectiveness and cost-containment, regulation, and ensuring quality will all be priorities in planning HSCT development in the region.

Causes of New-Onset Seizures and Their Treatment in Children With Non-CNS Malignancies: A Retrospective Study in a Tertiary Care Center.

BACKGROUND: Seizures occur in up to 13% of children with non-central nervous system (CNS) malignancies, but little is known about their causes and optimal diagnostic and therapeutic approaches. Here we sought to determine etiologies and clinical trajectories of new-onset seizures in this patient population. METHODS: A retrospective chart review over a 10-year period was conducted at the American University of Beirut Medical Center to identify children with non-CNS malignancies and at least one new-onset seizure. Data were collected on the underlying malignancy, seizure etiology, clinical course, treatments, electroencephalograms, and brain imaging. RESULTS: New-onset seizures occurred in 56 children (2-year median follow-up), most commonly in the context of acute lymphoblastic leukemia, lymphomas, and sarcomas. In 19 children, the first seizure consisted of status epilepticus. The most common etiologies were cerebrovascular accidents, posterior reversible encephalopathy syndrome, and metastasis. Forty-nine patients received anti-seizure medications (ASMs). Withdrawal of ASMs was successful in 19 children with normal initial or follow-up brain imaging but failed in three patients with persistent brain lesions. The remaining children, all of whom except two had structural brain abnormalities, received chronic ASMs and remained seizure free for a median period of 2 years at the last follow-up in survivors. CONCLUSIONS: Not only are seizures in children with non-CNS cancers often indicative of a serious brain insult, but they can also be challenging in the form of status epilepticus. An urgent diagnostic evaluation is therefore needed to expedite treatment, which should be tailored to the chronicity of the underlying cause.

Heritable cancer predisposition testing in pediatric cancer patients excluding retinoblastoma in a middle-income country.

Resource-limited settings often have financial barriers to genetic testing for heritable cancer. This retrospective study investigated the pattern of heritable cancer predisposition testing in a middle-income country over the period 2014-2021, excluding retinoblastoma. After establishing a specific fund in 2019, rate of tests increased from 1.1% to 10.9% of new diagnoses. Most common testing was for constitutional mismatch repair deficiency (CMMRD), rhabdoid predisposition syndrome, TP53 (tumor protein 53) mutation, and hereditary cancer panel. Of 33 patients, 13 (39%) tested positive, 12 (36%) negative, and eight (24%) had variants of unknown significance. Positivity rate was 43% for a clinical phenotype and 44% for a tumor type indication.

Ticagrelor vs placebo for the reduction of vaso-occlusive crises in pediatric sickle cell disease: the HESTIA3 study.

The phase 3 HESTIA3 study assessed the efficacy and safety of the reversible P2Y12 inhibitor ticagrelor vs placebo in preventing vaso-occlusive crises in pediatric patients with sickle cell disease (SCD). Patients aged 2 to 17 years were randomly assigned 1:1 to receive weight-based doses of ticagrelor or matching placebo. The primary end point was the rate of vaso-occlusive crises, a composite of painful crises and/or acute chest syndrome (ACS). Key secondary end points included number and duration of painful crises, number of ACS events, and number of vaso-occlusive crises requiring hospitalization or emergency department visits. Exploratory end points included the effect of ticagrelor on platelet activation. In total, 193 patients (ticagrelor, n = 101; placebo, n = 92) underwent randomization at 53 sites across 16 countries. The study was terminated 4 months before planned completion for lack of efficacy. Median ticagrelor exposure duration was 296.5 days. The primary end point was not met: estimated yearly incidence of vaso-occlusive crises was 2.74 in the ticagrelor group and 2.60 in the placebo group (rate ratio, 1.06; 95% confidence interval, 0.75-1.50; P = .7597). There was no evidence of efficacy for ticagrelor vs placebo across secondary end points. Median platelet inhibition with ticagrelor at 6 months was 34.9% predose and 55.7% at 2 hours' postdose. Nine patients (9%) in the ticagrelor group and eight patients (9%) in the placebo group had at least one bleeding event. In conclusion, no reduction of vaso-occlusive crises was seen with ticagrelor vs placebo in these pediatric patients with SCD. This trial was registered at www.clinicaltrials.gov as #NCT03615924.

Voxelotor for the treatment of sickle cell disease in pediatric patients.

INTRODUCTION: Sickle cell disease (SCD) describes a group of heritable blood disorders caused by the polymerization of sickle hemoglobin (HbS). HbS polymerization leads to anemia and vaso-occlusion, a process that impedes delivery of oxygen to tissues throughout the body, resulting in end-organ damage (EOD). Given the lifelong complications associated with SCD, identification and treatment of early symptoms in childhood is increasingly important. Voxelotor is an oral therapy that inhibits the polymerization of HbS and offers a unique therapeutic mechanism to reduce the causes of EOD. Voxelotor was approved in December 2021 for the treatment of SCD in patients aged ≥4 years. AREAS COVERED: Clinical data on the use of voxelotor in pediatric patients with SCD is reviewed. Ongoing studies examining the clinical efficacy and safety profile of voxelotor in pediatric patients are compared with similar clinical outcomes in adults with SCD. Planned studies of voxelotor in children are also discussed. EXPERT OPINION: Voxelotor provides a unique therapeutic option to target the root causes of EOD and can potentially be used alongside other SCD therapies. Future studies directly observing the impact of voxelotor on EOD will be important for determining treatment strategies.

Brucellosis causing bone marrow aplasia in an 11-year-old patient with complete recovery after treatment.

Brucellosis is one of the most prevalent zoonotic infections in the Middle East. The disease may present with a range of symptoms from a simple febrile illness to severe invasive infections affecting different organ systems (meningitis, osteomyelitis). In this paper we present an eleven-year-old girl who was diagnosed with "idiopathic bone marrow aplasia" and planned for hematopoietic stem cell transplant (HSCT), when pre-transplant work-up showed high brucella titers. The patient was started on doxycycline, rifampin and gentamicin initially, with discontinuation of the latter 3 weeks into therapy. She recovered completely after 8 months of treatment.

Hyper-CVAD combined with Venetoclax for relapsed pediatric blastic plasmacytoid dendritic cell neoplasm (BPDCN): A case report and literature review.

Blastic Plasmacytoid Dendritic Cell Neoplasm (BPDCN) is a very rare type of leukemia in children, Although BPDCN is a chemo-sensitive tumor, the relapse rate is very high. Tagraxofusp, which is a CD123-directed cytotoxin has been used as a targeted therapy and has shown promising results in patients with either untreated or relapsed BPDCN. There is also a good response with Venetoclax, a selective BCL2 inhibitor, as a single agent or in combination with chemotherapy. Here, we described a case of a pediatric patient with BPDCN who was treated initially with ALL-based regimen followed by Allogeneic hematopoietic stem-cell transplantation (HSCT) and salvaged with Hyper-CVAD combined with Venetoclax after testicular relapse 11 months post Allogeneic HSCT.

Safety and efficacy of voxelotor in pediatric patients with sickle cell disease aged 4 to 11 years.

BACKGROUND: Sickle cell disease (SCD) is a devastating, multisystemic disorder that affects millions of people worldwide. The earliest clinical manifestations of SCD can affect infants as young as 6 months of age, and pediatric patients are at risk for acute and life-threatening complications. Early intervention with treatments that target the underlying pathophysiological mechanism of SCD, sickle hemoglobin (HbS) polymerization, are expected to slow disease progression and circumvent disease-associated morbidity and mortality. PROCEDURE: The HOPE-KIDS 1 trial (NCT02850406) is an ongoing four-part, phase 2a, open-label, single- and multiple-dose study to evaluate the pharmacokinetics, efficacy, and safety of voxelotor-a first-in-class HbS polymerization inhibitor-in patients aged 6 months to 17 years with SCD. Initial findings from a cohort of 45 patients aged 4 to 11 years who received voxelotor treatment for up to 48 weeks are reported. RESULTS: Hemoglobin (Hb) response, defined as a >1.0 g/dl increase from baseline, was achieved at week 24 by 47% (n = 16/34) of patients with Hb measurements at baseline and week 24. At week 24, 35% (n = 12/34) and 21% (n = 7/34) of patients had a >1.5 g/dl increase and a >2.0 g/dl increase from baseline in Hb concentration, respectively. Concurrent improvements in hemolytic markers were observed. Voxelotor was well tolerated in this young cohort, with no newly emerging safety signals. CONCLUSIONS: Based on its mechanism as an HbS polymerization inhibitor, voxelotor improves Hb levels and markers of hemolysis and has the potential to mitigate SCD-related complications; these results support its use in patients aged ≥4 years.

Diagnosis and Treatment of a Patient With Severe Combined Immunodeficiency Due to a Novel Homozygous Mutation in the IL-7Rα Chain.

The interleukin-7 receptor (IL-7R) is expressed on lymphoid cells and plays an important role in the development, homeostasis, survival, and proliferation of T cells. Bi-allelic mutations in the IL-7Rα chain abolish T cell development and function resulting in severe combined immunodeficiency disease. In this manuscript, we investigate a 1 year-old patient born to consanguineous parents, who suffered from autoimmune hemolytic anemia since birth associated with recurrent severe infections. Flow cytometric analysis of the patient's peripheral blood demonstrated elevated numbers of B and NK cells, decreased numbers of T cells, defective thymic output, a predominance of memory T cells, and absent T cell proliferation. Next Generation Sequencing identified a novel homozygous pathogenic mutation in IL7RA (c.379G>A) that resulted in aberrant IL7RA RNA splicing and absent IL-7Rα expression. The patient was successfully transplanted using her HLA-matched relative as donor. One year after transplant, the patient is clinically stable with normal reconstitution of donor T cells that express IL-7Rα, a significant increase in the percentages of recent thymic emigrant and peripheral T cells, normalization of naïve and memory T cells, and restoration of her T cell's proliferative response. Therefore, using genetic and functional approaches, we identified a novel deleterious mutation in IL-7Rα that results in T-B+NK+ phenotype, and report successful hematopoietic stem cell transplantation of the patient. This represents the first bedside-to-bench-and-back case entirely performed on a patient with severe combined immunodeficiency at the American University of Beirut Medical Center.

Vincristine-induced neurotoxicity in pediatric patients with rhabdomyosarcoma: A retrospective analysis of clinical features and outcome.

Vincristine is an essential component of rhabdomyosarcoma treatment. However, it can cause motor neurotoxicity, necessitating dose reductions. We retrospectively reviewed the rates and patterns of vincristine-induced motor neuropathy in children treated for rhabdomyosarcoma, and investigated effects on outcome. Fifteen of 43 patients (35%) developed motor neuropathies necessitating dose reductions, which ranged from 1.7% to 58% of planned cumulative dose. Older age was the only significant clinical risk factor. Almost half (47%) recovered during treatment with subsequent dose escalation. Most patients had complete resolution of symptoms upon follow-up. There was no discernible effect of treatment reduction on survival or relapse rates.

Long-term follow-up of children treated with the Repiphysis expandable prosthesis for lower extremity bone sarcoma.

Expandable endoprostheses provide a limb salvage option for skeletally immature patients with bone sarcoma of the lower extremities. Initial reports of the Repiphysis prosthesis were encouraging; however, medium-term follow-up revealed high complication rates. We report on the long-term follow-up of a cohort of patients treated with the Repiphysis prosthesis. Eleven patients were included in the study. Data collected included sex, age at surgery, duration of follow-up, site of disease, histologic diagnosis, number of lengthening sessions, amount lengthened, postoperative complications, endoprosthetic failure, mode of endoprosthetic failure, duration from index surgery to failure and to revision, type of revision surgery and final limb-length discrepancy. The average duration of follow-up from the time of surgery was 180 months (range, 144-215 months). Fifteen Repiphysis implants were used in 11 patients. All implants failed with an average time from surgery to failure of 36 months (range, 3-72 months). Twenty-four complications were observed: one wound dehiscence, two deep infections, 18 mechanical failures, implant collapse with destruction of proximal tibia epiphysis in two and one periprosthetic proximal femur fracture with dislodgement of the stem. Despite being an option for limb salvage, the Repiphysis prosthesis has a high rate of mechanical failure and need for revision, similar to other expandable implants. The authors, therefore, recommend full disclosure of the potential short- and long-term complications and need for revision, as well as alternative treatment options if their use is considered. Level of evidence: IV (Therapeutic).

Treatment-induced cerebral sinus venous thrombosis in childhood acute lymphoblastic malignancies: New risk factors to consider.

BACKGROUND: Cerebral sinus venous thrombosis (CSVT) is one of the many side effects encountered during acute lymphoblastic leukemia (ALL) therapy. Due to the rarity of cases, lack of data, and consensus management, no recommendations exist to target the population at risk. METHODS: This is a retrospective chart review of 229 consecutive patients diagnosed with ALL with an age range of 1-21 years, treated at the Children's Cancer Center of Lebanon between October 2007 and February 2018. RESULTS: The incidence of CSVT was 10.5%. Using univariate analysis, increased risk of CSVT was observed with male gender, age >10 years, T-cell immunophenotype, intermediate/high-risk disease, maximum triglyceride (TG) level of >615 mg/dl, presence of mediastinal mass, and larger body surface area (BSA). With multivariate analysis, the only statistically significant risk factors were maximum TG level, BSA, presence of mediastinal mass, and risk stratification (intermediate/high risk). CONCLUSION: Our study was able to unveil TG level of >615 mg/dl, mediastinal mass, and a larger BSA as novel risk factors that have not been previously discussed in the literature.

The Spectrum of ß-Thalassemia Mutations in the Population Migration in Lebanon: A 6-Year Retrospective Study.

ß-Thalassemia (ß-thal) is highly prevalent among the Mediterranean populations. In Lebanon, the carrier rate of the disease is estimated to be around 2.0-3.0%. In this retrospective study, we determined the spectrum of ß-thal mutations in a total of 170 individuals from a sample of 140 Lebanese, Iraqi and Syrian refugee families in Lebanon, over a period from 2012 to 2018. Twenty-eight different ß-globin gene mutations were identified. The most prevalent mutations were IVS-I-110 (G>A) (HBB: c.93-21G>A), IVS-II-1 (G>A) (HBB: c.315+1G>A), IVS-I-6 (T>C) (HBB: c.92+6T>C) and IVS-I-1 (G>A) (HBB: c.92+1G>A), accounting for the majority of mutations found in HBB mutations analysed in 250 alleles. Ten different ß-globin gene mutations that were not previously described in Lebanon were identified in our study. These mutations include the IVS-II-848 (C>A) (HBB: c.316-3C>A), codons 9/10 (+T) (HBB: c.30_31insT), codon 15 (-T) (HBB: c.46delT), -86 (C>G) (HBB: c.-136C>G), Cap +22 (G>A) (HBB: c.-29G>A), -28 (A>C) (HBB: c.-78A>C), codon 7 (GAG>TAG) (HBB: c.22G>T), codon 26 (GAG>TAG) (HBB: c.79G>T), codons 41/42 (-TTCT) (HBB: c.126_129delCTTT), and codons 82/83 (-G) (HBB: c.250delG). Of these, six mutations [codons 9/10, codon 15 (-T), -86, codon 7, codon 26, codons 82/83) were identified in Lebanese samples only; one mutation (IVS-II-848) was identified in both Lebanese and Iraqis; and three mutations (Cap +22, -28, codons 41/42) were identified in Iraqi samples only. Further studies will help better delineate the spectrum of ß-thal mutations among different ethnic groups, and provide crucial prevention strategies.