The use of heliox in critical care.

This paper reviews the medical use of helium oxygen mixture in obstructive airway disease in patients with croup, narrow endotracheal tubes (ETTs), respiratory distress syndrome, asthma, bronchiolitis, as well as patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) and acute lung injury. In addition, some other indications of heliox use and some innovative methods of ventilation applied in pediatrics and adults are presented through review of the literature of current decade. Yet, to recommend heliox use seems to require more research based on clinical practice and observation through vaster and more robust investigations.

Epidemiology of hepatitis C in the Middle East.

The epidemiology of hepatitis C virus (HCV) infection is not well defined in the Middle East region. A review of the epidemiology and modes of transmission and spread of HCV infection in regions located in the Middle East, including Iran, Bahrain, Iraq, Oman, Qatar, Jordan, Kuwait, Saudi Arabia, United Arab Emirates, Cyprus, Sudan, Egypt, Pakistan, Syria, Turkey, Lebanon, Gaza Strip and West Bank, and Yemen, was undertaken. Public health strategies, well-programmed, population-based and certain HCV infection at-risk surveys, and transmission risk factors' settings detection are insufficient in some countries of this region. Since significant differences in prevalence and epidemiology of HCV exist among the Middle East countries or even inside the countries, control strategies should take these differences into account.

Immune response to hepatitis B vaccine in health-care workers.

This study was performed to study the immune response to hepatitis B virus (HBV) vaccine in health-care workers. Through a cross-sectional study, relevant information and blood samples from 151 healthcare workers at the Firuzgar hospital were studied. The age range of the study individuals was 20-59 years, with the mean and standard deviation being 35.11 and 10.06, respectively. There were 24 males (15.9%) and 127 females (84.1%). The mean and median of months after HBV vaccination was 63.42 and 49.00, respectively. The mean and median of anti-HBs titer in those who received HBV vaccination was 164.81 and 200 milli international units per milliliter (mIU/mL), respectively. Of the 129 HBV-vaccinated subjects, 103 (68.2%) had anti-HBs titer >10 and 26 (17.2%) had anti-HBs titer <10. There was no association between gender and anti-HBs titer, but vaccination and adequate completion of its courses were associated with higher anti-HBs titer (P < 0.05). Also, the logistic regression method showed that the association between duration after vaccination and age with anti-HBs titer was not statistically significant. Our study suggests that the HBV vaccine immunization program had obtained excellent efficacy. There is need for further investigation among subjects who are not vaccinated against HBV but are positive for anti-HBs as well as in HBV-vaccinated subjects with low anti-HBs titers, about possible low-level viremia and other causes of lower vaccine efficacy, particularly in health-care workers.

Epidemiology and transmission of hepatitis G virus infection in dialysis patients.

Hepatitis G virus (HGV) or GB-virus type C (GBV-C) is distributed globally and is present in the volunteer blood donor population. For epidemiological studies, HGV is of interest in hemodialysis patients who are at risk of parenterally transmitted infections. The role of HGV in producing illness and hepatic disease has yet to be determined. A review of literature was performed in 2009 to summarize scientific reports on epidemiology and pathogenesis of the HGV infection and its exposure through hemodialysis.

Impact of immunosuppression and chemotherapy on reactivation of viral hepatitis.

Chemotherapy drugs, biological medications that are used to treat cancer, may cause hepatic side effects. Patients with pre-existing viral hepatitis may be more susceptible to exacerbation of their underlying liver disease, and risk of drug-induced hepatotoxicity. We conducted a search on immunosuppression, and its impact on reactivation of viral hepatitis, using the electro-nic medical databases. Before starting chemotherapy, it is recommended to record the past history of liver disease and check for hepatitis B virus (HBV) and hepatitis C virus (HCV) serology. In immunosuppressed patients, radiation toxicity, graft versus host disease, hepatic veno-occlusive disease, acalculous cholecystitis, tumor infiltration, ischemia, other viruses such as CMV and her-pes virus, and systemic infection should also be considered. Transplant recipients with serologic evidence of previous infection with hepatitis B or C, or those who receive organs from a seropositive donor, should have viral load levels monitored before and after transplantation and, may also require treatment. We believe that there is a role for prophylactic use of antiviral treatment in patients at risk for HBV reactivation.

Implementing strategies for hepatitis B vaccination.

This study reviewed the effects of hepatitis B virus (HBV) vaccination programs on disease control and the need, if any, to introduce additional strategies taking into account the various risk factors of transmission. We performed a search conducted on vaccine administration, hepatitis B risk factors and the impact of HBV vaccination on prevention of disease, using the electronic database MEDLINE (1987 to 2008), EMBASE, OVID, Google (for Local websites and medical journals), Websites of Iranian universities and Iran medex in English and Persian language. We recommend in addition, to routinely practice the Extended Program of Immunization (EPI) schedules for infants as well as implementing HBV vaccination in selected adolescents at risk for HBV infection. Routine screening and immunization is mandatory in the following people: pregnant women and adults at risk for HBV infection including health-care workers, police, fire fighters, barbers, people with certain risk behaviors such as inmates of correctional facilities, injection-drug users and persons at risk for sexual transmission, as well as patients exposed to blood and blood products and those on chronic hemodialysis. Vaccine providers in areas with high rates of chronic HBV infection should assess infection screening by performing serologic tests in susceptible subjects to identify persons who require counseling and management. Also, additional studies are needed to determine the effectiveness of currently employed immunization strategies.

Serum gamma-glutamyltransferase, alanine aminotransferase, and aspartate aminotransferase activity in Iranian healthy blood donor men.

AIM: To determine serum gamma-glutamyltransferase (GGT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activity, and to assess their correlation with demographic and clinical findings in healthy blood donors. METHODS: This cross-sectional study was performed in 934 male blood donors, aged 18 to 68 years, who consecutively attended Tehran blood transfusion service in 2006. All participants were seronegative for HBV or HCV infections, non alcohol users, and all underwent a standard interview and anthropometric tests. Clinical and biochemical parameters including AST, ALT, and GGT activities were determined. Patients taking drugs known to cause hepatic fat deposition were excluded. For AST, ALT, and GGT variables, we used 33.33 and 66.66 percentiles, so that each of them was divided into three tertiles. RESULTS: Mean AST, ALT, and GGT activities were 25.26 +/- 12.58 U/L (normal range 5-35 U/L), 33.13 +/- 22.98 (normal range 5-35 U/L), and 25.11 +/- 18.32 (normal range 6-37 U/L), respectively. By univariate analyses, there were significant associations between increasing AST, ALT, or GGT tertiles and age, body weight, body mass index, and waist and hip circumferences (P<0.05). By multiple linear regression analyses, ALT was found to be positively correlated with dyslipidemia (B=6.988, P=0.038), whereas ALT and AST were negatively correlated with age. AST, ALT, and GGT levels had positive correlation with family history of liver disease (B=15.763, P<0.001), (B=32.345, P<0.001), (B=24.415, P<0.001), respectively. CONCLUSION: Although we did not determine the cutoffs of the upper normal limits for AST, ALT, and GGT levels, we would suggest screening asymptomatic patients with dyslipidemia and also subjects with a family history of liver disease.

The changing epidemiology of viral hepatitis B in Iran.

Hepatitis B virus (HBV) prevalence has decreased dramatically in Iranian population during the last decade, and now our country is classified as having low endemicity for hepatitis B infection. Improvement of the people's knowledge about HBV risk factors, national vaccination program since 1993 for all neonates, and vaccination of high risk groups might justify this decrease. The HBV vaccination started in infants in two provinces (Zanjan and Semnan) in 1989, and in 1993 the vaccination was included in the Expanded Program on Immunization (EPI) countrywide. After 13 years of implementation, the coverage has reached an appropriate level from 62% in 1993 to 94% in 2005. Evaluation of risk factors in HBV infected people is important for designing the strategies to control the disease. Intensifying HB vaccination of high risk groups, surveillance of hepatitis B infected subjects, and control on health state of refugees will further decrease the frequency of the disease in our country. Considering all possible routes of transmission in subjects without risk factors for infection is necessary. Changes in the pattern of transmission of new cases of hepatitis B, inform us of changes in the epidemiology of viral hepatitis B infection.

Seroepidemiologic study of hepatitis B virus, hepatitis C virus, human immunodeficiency virus and syphilis infections in Iranian blood donors.

To determine the frequency of hepatitis B, hepatitis C, Human Immunodeficiency Virus (HIV) and syphilis infections in Iranian blood donors. The prevalence of serological markers of hepatitis B, hepatitis C, HIV and syphilis infections were evaluated in 318029 consecutive volunteer blood donors attending to Tehran blood transfusion service from March 2005 to March 2006. Those positive for hepatitis B surface antigen, anti-HCV, anti-HIV1/2 and VDRL (venereal disease research laboratory) reactivity were analyzed with a second independent HBsAg enzyme immunoassay (EIA) and neutralization assay; an additional independent anti-HCV EIA and HCV-RIBA assay; second independent anti-HIV1/2 test, HIV western blot and fluorescent Treponemal Antibody Absorbed (FTA-ABS), respectively. In 318029 participants, prevalence of positive HBsAg, HCV RNA, HIV western blot and FTA-ABS was 1684 (0.487%), 323 (0.093%), 11 (0.003%) and 19 (0.005%), respectively. In 1014 subjects randomly selected from these 318029 participants, besides standard interview, physical exam and routine serologic tests; anthropometric and biochemical were studies. In this selected group frequency of HBsAg was 3 (0.29, 95% CI: 0-0.64%); frequency of anti-HCV was 21 (2.07%), but it was (0.09%, 95% CI: 0-0.30%) by confirmatory HCV RNA test; frequency of HIV-Abl, 2 was 8 (0.78%), but it was 2 (0.19%, 95% CI: 0-0.48%) by confirmatory test; frequency of RPR was 0 (0%, 95% CI: 0-0.30%). Despite excluding subjects with high-risk behaviors by standard interview and physical examination, still a few asymptomatic hepatitis B, hepatitis C, HIV-infected subjects existed among volunteer blood donors with demographic and biochemical findings similar to non-infected ones.

Association of promoter polymorphism of the CD14 C (-159) T endotoxin receptor gene with chronic hepatitis B.

AIM: To investigate whether single-nucleotide polymorphisms in the promoter regions of endotoxin-responsive genes CD14 C (-159) T is associated with chronic hepatitis B. METHODS: We obtained genomic DNA from 80 patients with established diagnosis of chronic hepatitis B and 126 healthy subjects served as a control population. The CD 14 C (-159) T polymorphism was investigated using an allele specific PCR method. RESULTS: Twenty seven percent of chronic hepatitis B patients and 75% of controls were heterozygous for CT genotype. The difference between the chronic hepatitis B and control groups was statistically significant [P < 0.0001; Odds ratio (OR) = 2.887; 95% CI: 1.609-5.178]. Twenty four point six percent of chronic hepatitis B and patients 12.3% of the control group were heterozygous for TT genotype. The difference between groups was not statistically significant (P = 0.256; OR = 0.658; 95% CI: 0.319-1.358). Forty eight point four percent of chronic hepatitis B patients and 12.7% of control were homozygote for CC genotype (P < 0.004; OR = 0.416; 95% CI: 0.229-0.755). The frequency of allele C was 61.9% and allele T was 38.1% in hepatitis B patients group. The frequency of allele C was 55.2% and allele T was 44.8% for the control group (P = 0.179; OR = 1.319; 95% CI: 0.881-1.977). CONCLUSION: The TT heterozygous genotype was not a risk factor for chronic hepatitis B. CC homozygote genotype is protective for hepatitis B. Lack of heterozygosis of genotype CT is a risk factor for chronic hepatitis B. Alleles C or T were not risk factors for chronic hepatitis B. These findings show the role of a single-nucleotide polymorphism at CD14/-159 on the development of chronic hepatitis B. Endotoxin susceptibility may play a role in the pathogenesis of chronic hepatitis B.

Cytotoxic T-lymphocyte antigen 4 gene polymorphisms and susceptibility to chronic hepatitis B.

AIM: To assess the three polymorphism regions within cytotoxic T-lymphocyte antigen 4 (CTLA-4) gene, a C/T base exchange in the promoter region -318 (CTLA-4 -318C/T), an A/G substitution in the exon 1 position 49 (CTLA-4 49A/G), a T/C substitution in 1172 (CTLA-4 -1172T/C) in patients with chronic hepatitis B. METHODS: Fifty-one patients with chronic hepatitis B virus infection and 150 healthy subjects were recruited sequentially as they presented to the hepatic clinic. Classification of chronic hepatitis B virus (HBV)-infected patients was as asymptomatic carrier state (26 patients) and chronic hepatitis B (25 patients). Genomic DNA was isolated from anti-coagulated peripheral blood Buffy coat using Milleros salting-out method. The presence of the CTLA-4 gene polymorphisms was determined using polymerase chain reaction amplification refractory mutation system (ARMS). RESULTS: We observed a significant association between -318 genotypes frequency (T+C-, T+C+, T-C+) and susceptibility to chronic hepatitis B (P=0.012, OR=0.49, 95%CI: 0.206-1.162). However, we did not observe a significant association for +49 genotype frequency (T+C+, T+C- T-C+) and -1172 genotype frequency (C+T+, T+C- C+T-) and state of disease. CONCLUSION: Our results suggest that CTLA-4 gene polymorphisms may partially be involved in the susceptibility to chronic hepatitis B.

Insulin resistance in chronic hepatitis B and C.

AIM: To determine whether insulin resistance occurs in patients with chronic hepatitis B (CHB) and chronic hepatitis C (CHC) and its relationship with the presence of liver fibrosis and steatosis. METHODS: Untreated patients with CHC (n=60) or CHB (n=40), similar in age, gender, body mass index and waist-hip ratio, were studied. Relationship between anthropometric, biochemical (fasting serum insulin, C-peptide, ferritin, iron, TNF-alpha, cholesterol, triglyceride, bilirubin, hemoglobin and platelet concentrations) and liver biopsy (43 CHC and 20 CHB patients) findings was investigated by insulin resistance determined via the homeostasis model assessment (HOMA-IR). RESULTS: The mean fasting serum insulin was 14.9 (11.9) mU/mL in CHC and 21.4 (17.4) in the CHB group (normal range 0.7-9; p=0.049) and mean HOMA-IR was 3.1 (2.6) in CHC versus 4.7 (4.1) in the CHB group (normal range 0.12-4.61; p=0.036). HOMA-IR was significantly associated with fibrosis stage in the CHC group (p=0.015), but not in the CHB group. CONCLUSION: Hyperinsulinemia occurs in chronic viral hepatitis B and hepatitis C; insulin resistance is associated with stage of fibrosis in hepatitis C.