Yosra Ben Youssef

In vitro susceptibility to amphotericin B, itraconazole, voriconazole, posaconazole and caspofungin of Aspergillus spp. isolated from patients with haematological malignancies in Tunisia

The resistance of Aspergillus species to antifungal is increasingly reported and the knowledge of the local epidemiology and antifungal susceptibility pattern is pivotal to define adequate treatment policies. Our study aimed to: 1) describe the in vitro antifungal susceptibility profile of the Aspergillus species isolated from patients with haematological malignancies in Tunisia; 2) compare the E-test and Sensititre Yeast-One assays for the detection of paradoxical growth and trailing effect, both phenotypes commonly exhibited by Aspergillus spp. upon exposure to caspofungin and 3) to evaluate the mortality rate in patients according to the causative Aspergillus species and the antifungal treatment.We tested amphotericin B, itraconazole, voriconazole, posaconazole and caspofungin against 48 Aspergillus isolates (17, A. niger; 18, A. flavus; 9, A. tubingensis; 1, A. westerdijkiae; and 1, A. ochraceus) with the E-test. Minimal inhibition concentrations were above the epidemiological cut-off values for amphotericin B in 67% of A. flavus strains; for caspofungin in 22% of A. flavus strains; and for itraconazole in 22% of A. tubingensis strains, voriconazole and posaconazole MICs were below the epidemiological cut-off values for all strains.When exposed to caspofungin, 42% of the strains exhibited trailing effect and 38% paradoxical growth. Trailing effect occurred in 61% of A. flavus strains and paradoxical growth in 62% of Aspergillus section Nigri strains. E-test and Sensititre Yeast-One assays were only fairly concordant for the detection of these phenotypes. Repeatability of both assays was high for trailing effect but poor for paradoxical growth. The relatively high frequency of amphotericin B resistant strains makes voriconazole best adapted as a first-line treatment of invasive aspergillosis from amphotericin B to voriconazole in this hospital.

Familial hematological malignancies: ASXL1 gene investigation

AbstractPurposeFamilial aggregation among patients with several hematological malignancies has been revealed. This emphasizes the importance of genetic factors. Only few genes predisposing to familial hematological malignancies have been reported until now due to the low occurrence. We have described in previous study PRF1 and CEBPA variants that might contribute to the background of genetic factors, which encourage us to extend our investigations to other cooperating genes. The aim of this study is to determine whether germline additional sex combs-like 1 (ASXL1) gene mutations may be involved?Methods/patientsIn this study, we investigated the candidate gene ASXL1 by direct sequencing in 88 unrelated Tunisian and French families with aggregated hematological malignancies.ResultsWe report a new p.Arg402Gln germline missense substitution in two related Tunisian patients which has not been previously described. We identified here this variant for the first time in non-Hodgkin lymphoma. The p.Arg402Gln variant was not found in 200 control chromosomes. In silico analysis has predicted potential deleterious effect on ASXL1 protein.ConclusionsFrom an extended candidate genes analyzed in the field of familial hematological malignancies, ASXL1 might be involved. This variant should be considered since a potential damaging effect was predicted by in silico analysis, with a view to develop functional assay in order to investigate the biological assessment.

Chronic Myeloid Leukemia as a Secondary Malignancy after Lymphoma in a Child. A Case Report and Review of the Literature

Background: Philadelphia chromosome-positive chronic myeloid leukemia (CML) in children is very rare. CML occurring as a secondary malignancy in individuals treated for diffuse large B-cell lymphoma (DLBCL) is also rare. Case Report: We present the case of a 5-year-old female patient who developed a right orbital mass that was diagnosed as DLBCL. 9 months after receiving treatment for DLBCL, she presented with a white cell count of 250,000/mm3. Peripheral blood and bone marrow (BM) evaluation revealed a myeloproliferative disorder. Cytogenetic and molecular studies demonstrated the presence of t(9;22). CML following DLBCL has not been previously described in the younger population. To our knowledge, this is the first report of a child who developed a CML as a second malignancy after DLBCL. Therapy-related CML and non-therapy-related secondary CML are discussed as potential explanations of this highly unusual clinical presentation. Conclusion: Hematological disorders such as CML may occur after lymphomas. With the increased use of BM cytogenetic studies during staging for lymphoid malignancies, future studies may be able to clarify the question of whether the CML clone in some of these patients existed before treatment for lymphoma.

Cytogenetic profile of a large cohort of Tunisian de novo acute myeloid leukemia.

Abstract Background: Cytogenetic data are essential not only for the diagnosis of acute myeloid leukemia but also for the evaluation of prognosis. Large systematic studies of cytogenetic aberrations in patients with acute myeloid leukaemia (AML) from Arab countries are not available. Methods: We analysed 631 consecutive newly diagnosed AML patients by conventional cytogenetics and compared our results with reports from other regions of the world. There were 97 (15·4%) children and 534 (84·6%) adults. Results: Abnormal karyotypes were found in 397 (62·9%) of all cases. T(15;17) and t(8;21) were the most frequent chromosomal abnormalities observed in 83 (13·2%) and in 78 (12·4%) patients, respectively. –5/del(5q) and −7/del(7q) were less frequent, seen in only 14 (2·2%) and 19 (3%) cases, respectively. Trisomy 8 was found in 44 (7%) of our patients followed by 11q23 rearrangements seen in 24 (3·8%) and then by inv(16) observed in only 22 (3·5%) of all cases. Unusual or novel cytogenetic abnormalities were found in 107 (17%) of our patients. Discussion: Although we confirmed, as usually described, that some recurrent cytogenetic abnormalities are correlated with the FAB subtypes, we noted however that some of them vary in frequency among different geographical areas and ethnic groups. This finding suggests a geographic heterogeneity in the pathogenesis of AML but more extensive epidemiological studies are required to confirm this.

Molecular study of the perforin gene in familial hematological malignancies

Perforin gene (PRF1) mutations have been identified in some patients diagnosed with the familial form of hemophagocytic lymphohistiocytosis (HLH) and in patients with lymphoma. The aim of the present study was to determine whether patients with a familial aggregation of hematological malignancies harbor germline perforin gene mutations. For this purpose, 81 unrelated families from Tunisia and France with aggregated hematological malignancies were investigated. The variants detected in the PRF1 coding region amounted to 3.7% (3/81). Two of the three variants identified were previously described: the p.Ala91Val pathogenic mutation and the p.Asn252Ser polymorphism. A new p.Ala 211Val missense substitution was identified in two related Tunisian patients. In order to assess the pathogenicity of this new variation, bioinformatic tools were used to predict its effects on the perforin protein structure and at the mRNA level. The segregation of the mutant allele was studied in the family of interest and a control population was screened. The fact that this variant was not found to occur in 200 control chromosomes suggests that it may be pathogenic. However, overexpression of mutated PRF1 in rat basophilic leukemia cells did not affect the lytic function of perforin differently from the wild type protein.

Differentiation of Fanconi anemia and aplastic anemia using mitomycin C test in Tunisia

Fanconi anemia (FA) is a recessive chromosomal instability syndrome that is clinically characterized by multiple symptoms. Chromosome breakage hypersensitivity to alkylating agents is the gold standard test for FA diagnosis. In this study, we provide a detailed laboratory protocol for accurate assessment of FA diagnosis based on mitomycin C (MMC) test. Induced chromosomal breakage study was successful in 171 out of 205 aplastic anemia (AA) patients. According to the sensitivity of MMC at 50 ng/ml, 38 patients (22.22%) were diagnosed as affected and 132 patients (77.17%) as unaffected. Somatic mosaicism was suspected in an 11-year-old patient with a FA phenotype. Twenty-six siblings of FA patients were also evaluated and five of them (19.23%) were diagnosed as FA. From this study, a standard protocol for diagnosis of FA was developed. It is routinely used as a diagnostic test of FA in Tunisia.

A novel t(3;12)(q21;p13) translocation in a patient with accelerated chronic myeloid leukemia after imatinib and nilotinib therapy

The acquisition of secondary chromosomal aberrations in chronic myeloid leukemia (CML) patients with Philadelphia chromosome-positive (Ph+) karyotype signifies clonal evolution associated with the progression of the disease to its accelerated or blastic phase. Therefore, these aberrations have clinical and biological significance. T(3;12)(q26;p13), which is a recurrent chromosomal aberration observed in myeloid malignancies, is typically associated with dysplasia of megakaryocytes, multilineage involvement, short duration of any blastic phase, and extremely poor prognosis. We have identified a recurrent reciprocal translocation between chromosomes 3 and 12 with different breakpoint at bands 3q21 in the malignant cells from a 28-year-old man. The patient was initially diagnosed as having Ph+ CML in the chronic phase. The t(3;12)(q21;p13) translocation occurred 4 years after the patient was first diagnosed with CML while undergoing tyrosine kinase inhibitor therapy. We confirmed the t(3;12)(q21;p13) translocation via fluorescence in situ hybridization assay by using whole-chromosome paint probes for chromosomes 3 and 12. Our findings demonstrate that, similar to other recurrent translocations involving 3q26 such as t(3;3) and t(3;21), the t(3;12)(q21;p13) translocation is implicated not only in myelodysplastic syndrome and acute myeloid leukemia but also in the progression of CML. These findings extend the disease spectrum of this cytogenetic aberration.

GATA2 gene analysis in several forms of hematological malignancies including familial aggregations

The genetic predisposition to familial hematological malignancies has been previously reported highlighting inherited gene mutations. Several genes have been reported but genetic basis remains not well defined. In this study, we extended our investigation to a potential candidate GATA2 gene which was analyzed by direct sequencing in 119 cases including familial aggregations with a variety of hematological malignancies and sporadic acute leukemia belonging to Tunisian and French populations. We reported a deleterious p.Arg396Gln GATA2 mutation in one patient diagnosed with both sporadic acute myeloid leukemia (AML) and breast cancer. We also reported several GATA2 variations in familial cases. The absence of deleterious mutations in this large cohort of familial aggregations of hematological malignancies may strengthen the hypothesis that GATA2 mutations are an important predisposing factor, although as a secondary genetic event, required for the development of overt malignant disease.

Multiple myeloma following essential thrombocythemia

The association of essential thrombocythemia and multiple myeloma is extremely rare, with only three patients previously treated with hydroxyurea reported in the literature until now. In this paper, we report the case of a 66 year old male who developed IgG-kappa M six years after the diagnosis of essential thrombocythemia, for which he had received hydroyurea. The possible etiological and pathogenic link between both these entities is here discussed.

Synchronous Thyroid and Gastric Mantle Cell Lymphoma

Introduction: Mantle cell lymphoma (MCL) is a distinct entity within the World Health Organization classification of lymphoid neoplasm and represents approximately 8% of lymphoma. Patients with mantle-cell lymphoma typically present with extensive disease and involvement of multiple lymph nodes as well as the spleen, bone marrow, blood, and gastrointestinal tract. MCL of the thyroid occurs exceptionally. The MCL of the stomach is also an exceptional occurrence. Observation: We describe the case of a 58-year-old male who was diagnosed with thyroid and gastric MCL. The patient was classified into high risk group according to the Mantle Cell Lymphoma International Prognostic Index (MIPI). The R-CHOP (Rituximab, Cyclophosphamide, Adriablastine, Vincristine and Prednisone) regimen was started and complete remission was achieved after 8 Case Study Zahra et al.; IJMPCR, 8(1): 1-6, 2016; Article no.IJMPCR.29229 2 courses. He currently receives a maintenance treatment with rituximab every two months. Conclusion: This case is a combination of two rather infrequent extranodal localizations of the MCL.