Assessment of Molecular Markers in AML Patients: A Hospital-Based Study in Lebanon.

BACKGROUND: In the past, research has been focused on elucidating the molecular genetics and epigenetic basis of acute myelogenous leukemia (AML). This has led to the change in the classification and management of AML patients. Because no molecular studies regarding AML characterization in Lebanese patients had yet been reported, we decided to determine in our institution the prevalence of the recurrent genetic rearrangements t(8;21), inv(16), t(15;17) and Fms-like (Suzanne McDonough feline sarcoma) tyrosine kinase 3 (FLT3) and nucleophosmin (NPM1) mutations. MATERIALS AND METHODS: Fusion gene transcripts from chromosome aberrations were analyzed according to standardized reverse transcription polymerase chain reactions after the report of BIOMED-1 concerted action: investigation of minimal residual disease in acute leukemia. FLT3 and NPM1 mutations were screened using home-brew methodologies. RESULTS: We reviewed 144 bone marrow samples from AML patients referred to Saint George Hospital for molecular and cytogenetic studies from September 2006 to July 2014. The male to female patient ratio was 1.34 to 1. We detected the inv(16) in 6 patients [4.2%] (type A, 5 [83%]; type D, 1 [17%]), t(8;21) in 7 patients [4.9%] (e5e2), and t(15;17) in 36 patients [25.0%] (24 [67%] breakpoint cluster region 1 (bcr1), 12 [33%] bcr3). Other chromosomal abnormalities (trisomy 8, complex karyotype, t(6;9),…) were found in 44 patients [31.4%] and 51 [35.5%] cases showed normal karyotype. Among the normal karyotypes, 6 patients [11.8%] were FLT3-positive (4 [67%] internal tandem duplication [ITD], 2 [33%] D835V), 8 [15.7%] had type A NPM1 mutation and 8 [15.7%] type A NPM1 and FLT3/ITD concomitantly. CONCLUSION: Our results, except for the prevalence of acute promyelocytic leukemia, are concordant with those reported in the literature with approximately 35% of the patients cytogenetically normal. Testing patients with normal karyotype for other molecular markers such as CCAAT/enhancer-binding protein alpha mutations, isocitrate dehydrogenase 1/2 mutations, and mixed lineage leukemia rearrangements could therefore provide additional prognostic, predictive, and therapeutic values for AML patients.

Influenza A (H1N1) 2009 pandemia. The experience of a tertiary care center in Beirut.

INTRODUCTION: In March 2009, a new influenza virus strain emerged, currently known as the 2009 pandemic H1N1 virus. The virus first appeared in Mexico and rapidly spread globally to reach a pandemic level in June of the same year. We describe here the experience of one major referral center in Beirut, Lebanon. MATERIALS AND METHODS: The laboratory department at St. George Hospital University Medical Center received respiratory specimens from hospital wards, the emergency department, in addition to a considerable proportion collected directly from "outpatients" in the lab. We used the real time RT-PCR as our main diagnostic test. We collected data about the patients from the laboratory information system and from the hospital medical records department. RESULTS: From mid-August 2009 till the end of January 2010, a total of 1771 specimens were analyzed, with 948 (53.5%) returning positive for influenza A (H1N1) by RT-PCR. Only 79 patients with H1N1 infection required hospitalization. Most of H1N1 confirmed patients were children and adolescents aged 5 to 17 years and young adults between 25 and 44 years. The most common symptoms at presentation were: fever, cough, shortness of breath, chills, rhinorrhea or nasal congestion, as well as gastrointestinal symptoms. Twenty-three patients required ICU care and eight patients died. The vast majority had an uncomplicated course of illness and was managed in an outpatient setting. CONCLUSION: The percentage of positive tests during the pandemia was significantly elevated, although few patients experienced drastic clinical outcomes.

Pharmacogenetics of coumarin dosing: prevalence of CYP2C9 and VKORC1 polymorphisms in the Lebanese population.

BACKGROUND: Polymorphisms in the genes encoding the cytochrome P450 2C9 enzyme (CYP2C9) and the vitamin K epoxide reductase (VKORC1) are known to contribute to variability in sensitivity to coumarins. Patients with certain common genetic variants of CYP2C9 (*2 & *3) or a VKORC1 polymorphism (-1639A Allele) require a lower dose of coumarin and are also at higher risk for over-anticoagulation and serious bleeding. In August 2007, the FDA label for warfarin was updated to highlight the benefit of genetic testing to predict warfarin response. AIM: Since the prevalence of these variants in the Lebanese population has not yet been reported, our aim was to determine the genotypes of CYP2C9 and VKORC1 in our population and to compare allele frequencies with previous findings from other ethnic groups. MATERIALS AND METHODS: CYP2C9 (*1/*2/*3) and VKORC1 (*A/*G) allelic variants were assessed by polymerase chain reaction-restriction fragment length polymorphism assays in a diversified sample of 161 unrelated healthy Lebanese volunteers. RESULTS: The allele frequencies of CYP2C9 *2 and *3 were 0.112 and 0.096 respectively, whereas VKORC1-1639A was 0.528. Carriers of the CYP2C9 *2 or *3 represented 34.2% of the subjects, whereas those of the VKORC1-1639A represented 73.9%. CONCLUSION: Our data show no significant difference in the frequency of CYP2C9 allelic variants when compared to the Caucasian population, whereas the allelic frequency of VKORC1-1639A was very high. Over 50% of the Lebanese population seem to be carrying more than two independent risk alleles, and is therefore potentially at high risk of over-anticoagulation.

Prevalence of CYP2C19 polymorphisms in the Lebanese population.

Clopidogrel is one of the most commonly prescribed drugs, as its combination with low-dose aspirin is the recommended oral anti-platelet therapy, to prevent ischaemic events following coronary syndromes or stent placement. Numerous recent studies have shown that polymorphisms in the gene encoding the cytochrome P450 (CYP450) 2C19 enzyme (CYP2C19) contribute to variability in response to clopidogrel; patients with certain common genetic variants of CYP2C19 (2, 3) have a reduced metabolism of clopidogrel and have a higher rate of cardiovascular events or stent thrombosis compared to patients with the CYP2C19 (1) allele. CYP2C19 2 is most common in Caucasians, Africans and Asians while CYP2C19 3 has been found mostly in Asians. Since the prevalence of these variants in the Lebanese population has not yet been reported, our aim was to determine the genotypes of CYP2C19 in our population. CYP2C19 (1/2/3) variants were assessed by Polymerase Chain Reaction-Restriction Length Polymorphism (PCR-RFLP) assays in a representative sample of 161 unrelated healthy Lebanese volunteers. The allele frequencies of CYP2C19 2 and 3 were 0.13 and 0.03. Carriers of the CYP2C19 2 or 3 represented 24.2% of the subjects. Our data show no significant difference in the frequency of CYP2C19 allelic variants when compared to Caucasian populations and demonstrate that the application of the recent FDA recommendations would also be beneficial in Lebanon, allowing physicians to identify patients at high risk for atherothrombotic events, and eventually advising them to consider other antiplatelet medications or alternative dosing strategies in poor metabolizers.