A regional virtual case discussion forum in pediatric oncology: Experience of the Pediatric Oncology East and Mediterranean Group

BACKGROUND

The Pediatric Oncology East and Mediterranean (POEM) group that aims to share expertise among pediatric oncology providers across the Middle East, North Africa, and East Asia region initiated a virtual Case Discussion Forum (CDF) in 2013.

METHODS

Meeting records from September 2013 till June 2021 were reviewed. Detailed minutes were available starting August 2016; case data were analyzed including diagnoses, purpose of presentation and recommendations. A 38-item survey assessing perception of benefits, challenges, and opportunities of the forum was distributed to members of the POEM group and results analyzed.

RESULTS

A total of 140 cases were presented from 14 countries. After August 2016, 67 cases were presented, and those were analyzed regarding reasons for discussion, barriers, and recommendations. Details are presented in this report, and the most common challenges identified were related to histopathologic/molecular diagnosis (24%), imaging interpretation (18%), resource limitations (12%), and surgical difficulties (9%). A survey was distributed to all POEM members in 28 countries, and 76 responded. The main benefit reported was the provision of recommendations regarding treatment and evaluation, while the main challenges reported were time zone difference and workload. Recognized opportunities included conducting regionally relevant research studies based on clinical problems identified during discussions, and setting guidelines for resource-adapted treatment regimens.

CONCLUSIONS

The POEM CDF identified areas for multi-institutional regional studies and led to a twinning project between two centers in the region for improving diagnostic infrastructure. Such forums can identify specific resource limitations in pediatric cancer and direct efforts for targeted capacity building.

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.

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.

Wiskott-Aldrich Syndrome in four male siblings from a consanguineous family from Lebanon

BACKGROUND

Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency disorder (PID) characterized by microthrombocytopenia, bloody diarrhea, eczema, recurrent infections, and a high incidence of autoimmunity and malignancy.

OBJECTIVE

To investigate the mechanism of thrombocytopenia and infections in four boys of consanguineous parents from Lebanon.

METHODS

Patient gDNA was studied using Next Generation Sequencing and Sanger Sequencing. Protein expression was determined by immunoblotting, and mRNA expression by semi-quantitative RT-PCR. F-actin polymerization and cellular proliferation were assayed by flow cytometry.

RESULTS

We identified a threonine to a methionine change at position 45 (T45M) of the WAS protein (WASp) that abolished protein expression and disturbed F-actin polymerization and T cell proliferation, but not B cell proliferation. In addition, the levels of the WAS-interacting protein (WIP) were significantly decreased in the patients.

CONCLUSION

The mutation identified severely destabilizes WASp and affects the downstream signaling events important for T cell function, but not B cell function. It was previously known that the stability of WASp depends on WIP. In this manuscript, we report that the stability of WIP also depends on WASp. Finally, it is important to suspect X-linked PIDs even in consanguineous families.

CLINICAL IMPLICATIONS

The patients are above the optimal age for transplant in WAS, and it is difficult to identify one or more donors for four patients, therefore, they represent ideal candidates for gene therapy or interleukin-2 therapy.