Genetic backgrounds and clinical characteristics of congenital neutropenias in Israel.

BACKGROUND: Congenital neutropenias are characterized by severe infections and a high risk of myeloid transformation; the causative genes vary across ethnicities. The Israeli population is characterized by an ethnically diverse population with a high rate of consanguinity. OBJECTIVE: To evaluate the clinical and genetic spectrum of congenital neutropenias in Israel. METHODS: We included individuals with congenital neutropenias listed in the Israeli Inherited Bone Marrow Failure Registry. Sanger sequencing was performed for ELANE or G6PC3, and patients with wild-type ELANE/G6PC3 were referred for next-generation sequencing. RESULTS: Sixty-five patients with neutropenia were included. Of 51 patients with severe congenital neutropenia, 34 were genetically diagnosed, most commonly with variants in ELANE (15 patients). Nine patients had biallelic variants in G6PC3, all of consanguineous Muslim Arab origin. Other genes involved were SRP54, JAGN1, TAZ, and SLC37A4. Seven patients had cyclic neutropenia, all with pathogenic variants in ELANE, and seven had Shwachman-Diamond syndrome caused by biallelic SBDS variants. Eight patients (12%) developed myeloid transformation, including six patients with an unknown underlying genetic cause. Nineteen (29%) patients underwent hematopoietic stem cell transplantation, mostly due to insufficient response to treatment with granulocyte-colony stimulating factor or due to myeloid transformation. CONCLUSIONS: The genetic spectrum of congenital neutropenias in Israel is characterized by a high prevalence of G6PC3 variants and an absence of HAX1 mutations. Similar to other registries, for 26% of the patients, a molecular diagnosis was not achieved. However, myeloid transformation was common in this group, emphasizing the need for close follow-up.

Unique Ataxia-Oculomotor Apraxia 2 (AOA2) in Israel with Novel Variants, Atypical Late Presentation, and Possible Identification of a Poison Exon.

AOA2 is a rare progressive adolescent-onset disease characterised by cerebellar vermis atrophy, peripheral neuropathy and elevated serum alpha-fetoprotein (AFP) caused by pathogenic bi-allelic variants in SETX, encoding senataxin, involved in DNA repair and RNA maturation. Sanger sequencing of genomic DNA, co-segregation and oxidative stress functional studies were performed in Family 1. Trio whole-exome sequencing (WES), followed by SETX RNA and qRT-PCR analysis, were performed in Family 2. Sanger sequencing in Family 1 revealed two novel in-frame SETX deletion and duplication variants in trans (c.7009_7011del; p.Val2337del and c.7369_7371dup; p.His2457dup). Patients had increased induced chromosomal aberrations at baseline and following exposure to higher mitomycin-C concentration and increased sensitivity to oxidative stress at the lower mitomycin-C concentration in cell viability test. Trio WES in Family 2 revealed two novel SETX variants in trans, a nonsense variant (c.568C > T; p.Gln190*), and a deep intronic variant (c.5549-107A > G). Intronic variant analysis and SETX mRNA expression revealed activation of a cryptic exon introducing a premature stop codon (p.Met1850Lysfs*18) and resulting in aberrant splicing, as shown by qRT-PCR analysis, thus leading to higher levels of cryptic exon activation. Along with a second deleterious allele, this variant leads to low levels of SETX mRNA and disease manifestations. Our report expands the phenotypic spectrum of AOA2. Results provide initial support for the hypomorphic nature of the novel in-frame deletion and duplication variants in Family 1. Deep-intronic variant analysis of Family 2 variants potentially reveals a previously undescribed poison exon in the SETX gene, which may contribute to tailored therapy development.

Adult pre B-cell acute lymphoblastic leukemia with unusually large proportion of bone marrow CD45 bright/high SSc blasts.

BACKGROUND: We present a pre B-ALL patient with the rare clinical manifestation of extramedullary disease, and a normal hemogram. This patient's blasts expressed bright CD45 and high side scatter (SSc) placing the cells in the monocyte gate. METHODS: Samples from peripheral blood and bone marrow (BM) aspirate from a 50-year-old female patient were immunophenotyped by multiparametric flow cytometry. RESULTS: Flow cytometry studies of the BM aspirate showed a large monocyte gate with 90-95% of the cells expressing an abnormal B cell phenotype. Peripheral white blood cells count was normal and cytogenetic analysis of the BM revealed a normal karyotype. CONCLUSION: It was not possible, based on CD45/SSc to identify a lymphoblast population in this pre B-ALL patient. Although bright expression of CD45 B-ALL blasts has been associated with poor prognosis to the best of our knowledge, the combination of bright CD45 blasts with high SSc has not been reported. As CD45 expression vs. SSc is routinely measured in the diagnostics of acute leukemias, a possible association between CD45 bright positivity and extramedullary disease or prognosis warrants further exploration. © 2015 International Clinical Cytometry Society.

Bone mineral density utilization in patients with newly diagnosed multiple myeloma.

Bone disease is a major cause for morbidity in multiple myeloma (MM), with the main focus concerning the manifestation as osteolytic lesions. Bone mineral loss is another reflection of myeloma bone involvement. Recently, osteoporosis has been omitted as a defining criterion for symptomatic disease in MM. We conducted a retrospective study to evaluate the use of bone mineral density (BMD) exams by dual-energy X-ray absorptiometry (DXA) among MM patients in a tertiary medical care centre. One-hundred seventy three patients were included. The T-scores of lumbar spine (LS), left femur neck (FN) and left total hip (TH) were obtained and analysed. The extent of osteolytic disease was categorized based on six bony areas. There was a strong correlation between spine and femur's T-scores (r = 0.56-0.61, p < 0.0001), although different sets of variables were correlated with LS and femur's T-scores. There was no correlation between BMD measurements and osteolytic disease extent. Patients with vertebral fracture(s) had significant lower T-scores of the spine in comparison to patients without vertebral fractures. Sixty-three patients (36.4% of the cohort) had follow-up DXA exam. In general, there was an increase in the LS T-scores, while femoral values decreased. However, in patients who achieved complete response (CR) and in those who retained CR during follow-up, femoral BMD increased as well. Because correlation between BMD and the extent of osteolytic lesions was not seen, our data support the recent exclusion of BMD assessment from the definition of symptomatic myeloma. Still, its use should be considered for evaluation of age- or therapy-related osteoporosis. Copyright © 2016 John Wiley & Sons, Ltd.

Acute promyelocytic leukemia with isochromosome 17q and cryptic PML-RARA successfully treated with all-trans retinoic acid and arsenic trioxide.

Acute promyelocytic leukemia (APL) is a subtype of acute leukemia that is characterized by typical morphology, bleeding events and distinct chromosomal aberrations, usually the t(15;17)(q22;q21) translocation. Approximately 9% of APL patients harbor other translocations involving chromosome 17, such as the t(11;17)(q23;q21), t(5;17)(q35;q12-21), t(11;17)(q13;q21), and der(17). All-trans retinoic acid (ATRA) and arsenic trioxide (ATO) have specific targeted activities against the PML-RARA fusion protein. The combination of ATRA and ATO is reportedly superior to chemotherapy and ATRA as induction therapy for APL. The clinical significance of non-t(15:17) APL-related aberrations is controversial, with conflicting reports regarding sensitivity to modern, targeted therapy. Isochromosome 17q (iso(17q)) is rarely associated with APL and usually occurs concurrently with the t(15:17) translocation. No published data is available regarding the efficacy of ATO-based therapy for APL patients who harbor iso(17q). We report on an APL patient with iso(17q) as the sole cytogenetic aberration and a cryptic PML-RARA transcript, who was treated with ATRA and ATO after failure of chemotherapy and achieved complete remission. To our knowledge, this is the first published report of APL associated with iso(17q) as the sole cytogenetic aberration, which was successfully treated with an ATO containing regimen.

First line and salvage therapy with total therapy 3-based treatment for multiple myeloma- an extended single center experience.

Total therapy 3 is an intensified protocol for multiple myeloma (MM). The "real life" outcomes of this protocol were seldom reported. Data was obtained for 81 patients (newly diagnosed, n=49; progressive MM, n=32), most of which had high-risk parameters. Overall response rate following (V)DT-PACE was 96% and 75% for the newly diagnosed and progressive groups, respectively. Median progression-free survival was 42.5 and 9 months, respectively. The 2-year overall survival was 88% and 40%, respectively. Treatment with (V)DT-PACE achieves high response rate among patients with high-risk disease, which can be translated into long-term remission only for newly diagnosed patients.