Hepatitis C virus infection and type 2 diabetes mellitus in Mexican patients.

OBJECTIVE: to measure the frequency of type 2 diabetes mellitus (T2DM) in patients with confirmed HCV infection. METHODS: we studied 125 adults reactive to anti-HCV antibodies (62.4 % women, mean age 46.8 years) who received confirmatory RT-PCR testing for viremia (63.2 % HCV-RNA-positive). RESULTS: twenty-two patients had T2DM (17.6 %, 95 % confidence interval: 11.8-25.3 %; mean National prevalence: 14.4 %), more frequent among patients with detectable viremia than in negative cases (23.3 % vs. 9.6 %, respectively; p = 0.04), and among those with advanced liver disease, than in compensated patients (28.9 % vs. 11.3 %, respectively; p = 0.01). Fourteen (17.7 %) patients received interferon-based treatment and 6 (42.8 %) had sustained virology response. None of the 6 responders had T2DM, but 2 of the 8 (25 %) non-responders had diabetes. T2DM patients were older than those without diabetes (57.7 vs. 44.5 years, p < 0.001), and after multivariate analysis, only age was significantly associated with diagnosis of T2DM. CONCLUSIONS: T2DM was highly prevalent among patients with chronic HCV infection. Age was the most important determining factor.

FCGR3A V(176) polymorphism for systemic lupus erythematosus susceptibility in Mexican population.

The objective of this study is to establish whether there is an association between the presence of FCGR3A V(176) polymorphism with SLE or its manifestations. We included 94 patients according to the 1982 ACR criteria as well as 98 controls matched by age and gender. The 11 ACR diagnostic criteria were analyzed on the clinical files. The polymorphism FCGR3A V(176) was determined by direct sequencing. There was not an association between the polymorphism FCGR3A V(176) with SLE or its main manifestations. The allelic frequency for F(176) was: 0.80 and 0.72 in cases and controls, respectively (P = 0.09, IC95%: 0.42-1.07); and the genotypic frequency in the group of cases was: 0.65 for homozygotes F(176)/F(176), 0.30 for heterozygotes and 0.05 for the homozygotes V(176)/V(176), while for the control group it was 0.53, 0.39 and 0.08, respectively. The polymorphism FCGR3A V(176) is not associated with SLE or any of its manifestations in patients with SLE from the West of Mexico.

A low steady HBsAg seroprevalence is associated with a low incidence of HBV-related liver cirrhosis and hepatocellular carcinoma in Mexico: a systematic review.

To address the relationship between hepatitis B virus (HBV) endemicity and HBV-related liver diseases in Mexico. Research literature reporting on HBsAg and antibody to hepatitis B core antigen (anti-HBc) prevalence in Mexican study groups were searched in NLM Gateway, PubMed, IMBIOMED, and others. Weighted mean prevalence (WMP) was calculated from the results of each study group. A total of 50 studies were analyzed. Three nationwide surveys revealed an HBsAg seroprevalence of less than 0.3%. Horizontal transmission of HBV infection occurred mainly by sexual activity and exposure to both contaminated surgical equipment and body fluids. High-risk groups exposed to these factors included healthcare workers, pregnant women, female sex workers, hemodialysis patients, and emergency department attendees with an HBsAg WMP ranging from 1.05% (95% confidence interval [CI], 0.68-1.43) to 14.3% (95% CI, 9.5-19.1). A higher prevalence of anti-HBc in adults than those younger than 20 years was associated with the main risk factors. Anti-HBc WMP ranged from 3.13% (95% CI, 3.01-3.24) in blood donors to 27.7% (95% CI, 21.6-33.9) in hemodialysis patients. A heterogeneous distribution of HBV infection was detected, mainly in native Mexican groups with a high anti-HBc WMP of 42.0% (95% CI, 39.5-44.3) but with a low HBsAg WMP of 2.9% (95% CI 2.08-3.75). Estimations of the Mexican population growth rate and main risk factors suggest that HBsAg seroprevalence has remained steady since 1974. A low HBsAg prevalence is related to the low incidence of HBV-related liver cirrhosis and hepatocellular carcinoma (HCC) previously reported in Mexico.

Prediction of the hepatitis C viremia using immunoassay data and clinical expertise.

Detection of anti-hepatitis C virus (anti-HCV) antibodies may yield a high frequency of false-positive results in people at low risk. To date, no clinical rule had been developed to predict viremia in HCV-seropositive patients. Therefore, we aimed to generate a prediction rule on the basis of clinical and serologic data, which can be used in outpatient care. We selected 114 seropositive patients without antiviral treatment or hepatitis B coinfection. Subsequently we identified independent predictors of the hepatitis C viremia by logistic regression and selected the quantitative value of the screening test for anti-HCV antibodies with the best performance in detecting viremia. Then, we combined clinical and serologic data to generate different prediction rules. Ratio of immunoassay signal strength of the sample to cut-off (S/CO) >15 had accuracy, positive predictive value (PPV) and positive likelihood ratio (LR+) of 84%, 83%, and 3.7; respectively. The rule compounded of the antecedent of blood transfusion before 1993 and S/CO >15 performed the best in prediction of viremia in all patients, with accuracy, PPV and LR+ of 71%, 88%, and 5.6; respectively. In the group of asymptomatic patients this rule improved in efficacy of prediction, with accuracy, PPV and LR+ of 79%, 91% and 12.8; respectively. In conclusion, a clinical rule is better than S/CO alone in prediction of the hepatitis C viremia. In a patient that meet the rule the probability of having viremia is high, therefore, it can be indicated directly an assay for viral load instead of other supplemental tests, thus, saving time and economic resources.

Performance of the serologic and molecular screening of blood donations for the hepatitis B and C viruses in a Mexican Transfusion Center.

Nucleic acid-amplification testing (NAT) is not routinely practiced in blood banks from most low-income countries. We did an exploratory comparison of the performance of the standard immunoassay-based screening tests for the hepatitis B (HBV) and C (HCV) viruses with that of NAT, in blood donors. From January 1999 to March 2005, 94,806 blood donors were screened for anti-HCV antibodies and for hepatitis B surface antigen (HBsAg). Also, an exploratory period of molecular screening was carried out on 100 consecutive blood donors to detect HBV DNA and HCV RNA by home-made PCR techniques without sera pooling. In the 75-month period of serologic screening, HBsAg was detected in 219 donors (0.23%; 95% CI, 0.20- 0.26%) and anti-HCV antibodies in 922 (0.97%; 95% CI, 0.90-1.03%). The annual trend for HBsAg prevalence had a decreasing pattern over the years (p<0.001), whereas that for anti-HCV did not (p=0.19). In the molecular screening cohort, HBV DNA was detected in one donor (1%; 95% CI, 0-6%) and HCV RNA in another (1%; 95% CI, 0-6%). All these 100 donors tested negative to HBsAg and anti-HCV. Thus, the prevalence of positive results for HBV and HCV did not differ if considering immunoassays or NAT; nevertheless, these methods did not coincide in detecting HBV or HCV in the molecular screening cohort. In conclusion, NAT can detect cases of HBV and HCV infections that standard immunoassay techniques can not, even in a highly selected population at low risk, like blood donors. Large-scale studies are warranted for NAT to be considered as a systematic method for screening of HBV and HCV in Mexican blood banks.