Reconsideration of BCR-ABL protein flow cytometric immunobead assay: how potent to diagnose and monitor chronic myeloid leukemia?

INTRODUCTION: Chronic myeloid leukemia (CML) is typically associated with the Philadelphia chromosome, resulting in the production of BCR-ABL fusion oncoprotein with upregulated tyrosine kinase activity. We aimed to evaluate a new flow cytometric immunobead assay to detect BCR-ABL protein in a group of patients with CML. METHODS: We enrolled 49 patients with CML, whose qRT-PCR and/or cytogenetic analysis of Philadelphia chromosome aberration was available, including tyrosine kinase inhibitors (TKIs)-naïve and (TKIs)-treated patients with various levels of response. Twenty Philadelphia-negative healthy individuals were also enrolled to obtain analytical negative controls. Peripheral blood samples were analyzed for BCR-ABL fusion protein by flow cytometry. RESULTS: The BCR-ABL fusion protein flow cytometric assay seemed efficacious to both diagnose the presence (P-value <0.0001) and distinguish the levels (P-value = 0) of the Philadelphia chromosome aberration. Groups of TKI-naïve and TKI-treated patients as well as levels of molecular/cytogenetic response to TKI-therapy were effectively discriminated (P-value <0.01). The receiver operating characteristic (ROC) curve analysis indicated the diagnostic value of the assay as excellent (AUC = 0.95, P-value = 0). CONCLUSIONS: The evaluated BCR-ABL fusion protein assay might be useful for diagnosing and monitoring Philadelphia chromosome aberration.

Identification of optimal target gene regions for hepatitis B virus genotyping by DNA sequencing.

OBJECTIVES: DNA sequencing is the gold standard for hepatitis B virus (HBV) genotyping. We investigated the intergenotypic discriminatory capabilities of various target gene regions over the entire HBV genome, introducing a novel data evaluation approach generally applicable in viral genotyping. METHODS: Complete genome sequences of seventy HBV variants obtained from the sera of 50 Syrian patients were determined and assigned GenBank accession No. from JN257148 to JN257217. Nucleotide sequence contigs were analyzed together with the NCBI reference genome set of HBV genotypes. Nine target gene regions were analyzed by phylogenetic and scored BLAST analyses. Thirty-one overlapping 300-bp sequence segments over the entire genome were also analyzed using a scored BLAST analysis, and intergenotypic discriminatory capabilities were statistically estimated for each. RESULTS: Intergenotype discrimination was extremely significant when targeting either the complete genome, the entire coding sequence of either P or S genes, or any 300-bp sequence segment over the coding sequences of S protein or the polymerase N-terminal domain. Interestingly, intergenotypic discriminatory capability correlated negatively with intragenotype variation. CONCLUSIONS: The intragenotypic conservation of certain target gene regions determines the intergenotypic discriminatory capability and allows reliable genotyping with relatively short segments. Our referential genome-wide tabulated guide allows for selecting candidate target gene regions for sequencing-based HBV genotyping. © 2013 S. Karger AG, Basel.

Significance of screening antibodies to hepatitis B virus core antigen among Syrian blood donors.

BACKGROUND: Hepatitis B virus (HBV) transmission via hepatitis B surface antigen (HBsAg)-negative blood donors has been reported. While many countries have implemented screening antibodies to hepatitis B core antigen (anti-HBc) to further enhance transfusion safety, HBsAg is still the only obligatory HBV screening test of blood donors in Syria. OBJECTIVE: To evaluate the significance of screening anti-HBc to reduce the risk of transfusion transmitted HBV infection in Syria. METHODS/MATERIALS: A cohort cross-sectional prospective study included 1939 healthy blood donors assigned at the blood transfusion center of Damascus University. All donors were tested for HBsAg and anti-HBc. HBsAg-negative, anti-HBc-positive sera were further tested quantitatively for antibodies to hepatitis B surface antigen (anti-HBs) and 'anti-HBc alone' sera were considered for HBV quantitative real time polymerase chain reaction (qPCR). RESULTS: Among 1913 HBsAg-negative donors, 215 (11·2%) were anti-HBc-positive including 125 anti-HBs high-positive and 59 anti-HBs low-positive donors. The remaining 31 donors were 'anti-HBc alone', five of which were HBV DNA-positive. CONCLUSION: Our results suggest including anti-HBc as an additional screening test for blood donors in Syria to reduce the risk of HBV transmission. As the most cost-effective measure, anti-HBc-positive donors should be tested quantitatively for anti-HBs and only donors with no or low (<100 IU L(-1) ) anti-HBs should be deferred.

Prevalence of antibodies to hepatitis C virus among hemodialysis patients in Damascus, Syria.

BACKGROUND: Evaluation of the epidemiology of hepatitis C virus (HCV) infection was made possible by the development of a serological assay to detect antibodies to epitopes of HCV. Hemodialysis (HD) is considered to be one of the main risk factors of HCV transmission. Therefore, the prevalence of antibodies to HCV (anti-HCV) was studied in patients undergoing maintenance dialysis therapy. PATIENTS AND METHODS: Anti-HCV were detected using a third-generation assay. The study group consisted of HD patients, transplant recipients and staff members from two dialysis units in Damascus, Syria. RESULTS: The overall prevalence of anti-HCV among HD patients was 48.9%; 24.4% in one center (Al-Mouassat Hospital) and 88.6% in the other (Kidney Hospital). There was a significant correlation between prevalence of anti-HCV and duration of HD. The prevalence was 36.7% for patients on HD for < 3 years and 65% in patients on HD for > 3 years (p < 0.05). There was a significant correlation between anti-HCV positivity and elevated liver enzymes: alanine aminotransferase (ALT) and asparate aminotransferase (AST). However, there was no significant correlation between anti-HCV positivity and history of blood transfusion, exposure to hepatitis B virus, age and sex. The prevalence of anti-HCV among kidney transplant recipients was 48%, among staff members of the dialysis units it was 5.8%. CONCLUSION: Factors related to infrastructure and operational system might be responsible for the very high prevalence of anti-HCV found in one of the two units. There was no data available on anti-HCV status of transplant recipients prior to transplantation. However, the prevalence among those patients, which is very similar to that of HD patients, suggests that HD may be responsible for such high prevalence among this group. An intensive educational program for staff members and proper evaluation of the HD situation in the two units are needed.

Prevalence of hepatitis C virus antibodies among health care workers in Damascus, Syria.

OBJECTIVE: Health care workers exposed to accidental inoculation with infected blood represent a high risk group of acquiring hepatitis C virus infection. Hepatitis C virus is considered the most common parenterally transmitted pathogen to which needle-stick recipients are exposed. Therefore, the prevalence of hepatitis C virus antibodies among different health care workers was studied. METHODS: Antibodies of hepatitis C virus were studied by 3rd generation enzyme immunoassay. Hepatitis B surface antigen and antibodies to hepatitis B core were carried out using enzyme immunoassays. Liver enzymes (alanine aminotransferase, aspartate aminotransferase) and total bilirubin were measured using reagents on chemistry autoanalyzer. The studied group (189 members, aged 28.1+/-6.2 years, 86 males and 103 females) consisted of laboratory workers (65), hemodialysis staff (34), dentistry workers (24), surgery workers (35), and a 5th group contained other medical care workers (31) in Damascus, Syria. RESULTS: The prevalence of hepatitis C virus antibodies among health care workers was 3%. The positivity of anti-hepatitis C was 0% in the laboratory group, dentistry group, and surgery group. Whereas, it was 6% in the hemodialysis group, and 10% in the other medical workers group. The prevalence of hepatitis B surface antigen was 6% among health care workers in Damascus. Means of biochemical parameters were 23.2+/-15.9 U/L for alanine aminotransferase, 21.8+/-7.8 U/L for aspartate aminotransferase, and 0.58+/-0.35 mg/dl for total bilirubin. CONCLUSION: The prevalence of hepatitis C virus antibodies among health care workers was higher than the prevalence among the general population (1%) which was determined during our study. However, the prevalence of anti-hepatitis C virus is lower than the prevalence of hepatitis B surface antigen among health care workers. There was no significant difference between means of biochemical parameters in each health workers and the general population. Factors related to infrastructure and operational system might be responsible for such prevalence of anti-hepatitis C virus among health care workers. An intensive periodic educational program for the medical and paramedical staff is important, in order to minimize the prevalence of anti-hepatitis C virus among this important high risk group.

Hepatitis E in Damascus, Syria.

A hospital-based study of acute hepatitis was conducted in Damascus, Syria, from 1995 to 1998. One hundred ninety-three sera from defined acute hepatitis cases were screened by ELISA for IgM anti-HAV, HBsAg, IgM anti-HBc and anti-HCV. Serum samples negative for all markers indicating recent infection by hepatitis A, B, or C were tested for HEV markers. Overall, 47 cases (24.4%) had no detectable hepatitis markers (non-A-E). HAV infection was detected in 71.2% of all viral hepatitis cases. Acute hepatitis B and C constituted 24 and 1.4% of the cases, respectively. Only five cases of acute hepatitis E were noted. Of 47 patients who had non-A-E hepatitis, fifteen (31.9%) tested positive for IgG anti HEV. This study provides indirect evidence that HEV is very likely to be endemic in Damascus, Syria. It reports for the first time the occurrence of hepatitis E in the country, a health problem that should be investigated further.