Evaluation of skin prick test to screen dust mite sensitization in chronic respiratory diseases in Southern Vietnam

BACKGROUND: In the view of the epidemic growth of sensitization to indoor allergens in Southern Vietnam, there is a requirement to screen large population. OBJECTIVE: To evaluate skin prick tests (SPTs) as predictors of positive specific IgE (sIgE) to dust allergens, among patients with chronic respiratory diseases (CRDs). METHODS: The sensitization to Blomia tropicalis (Blo t), Dermatophagoides pteronissinus (Der p), and Blattella germanica allergens (Bla g) were evaluated among 610 CRD, both SPT (≥4 mm) and sIgE by immuno-CAP (≥0.7 kUA/L). RESULTS: Based on sIgE, 45%, 32%, and 33% of patients with CRD were sensitized to Blo t, Der p, and Bla g, respectively, compared to 19%, 18%, and 13% by SPT. The association between SPT and sIgE was statistically significant, though the Kappa factor was fair (i.e., 0.39 to 0.23). While the specificity of SPT to detect sensitization (compared to sIgE) was >90% among the whole population, the sensitivity was only 34%, 41%, and 24% for Bo t, Der p, and Bla g, suggesting that SPT was not enough sensitive to screen the indoor allergen sensitization. Though, among the < 10 pack-year (PY) smokers, the sensitivity was 43% for Blo t, 52% for Der p, and 61% for Blo t and/or Der p, compared to 27%, 30%, and 35% among the ≥10 PY smokers. The sensitivity/specificity was not associated with the diagnosis of asthma compared to chronic obstructive pulmonary disease. CONCLUSION: In the present circumstance, SPT to dust mites allergens can be used to detect a sensitization among CRD population in Southern Vietnam.

Efficacy of the intervention with anti-HBV immunoglobulin and hepatitis B vaccination within 24 hours after birth for neonates in Hanoi

Background: Previous studies showed that B hepatitis prevalence in Vietnam was very high and the rate of mother-to-child transmission was range from 44.7% to 45.2%. Objectives: Study on the efficacies of the interventional methods with anti-HBV immunoglobulin and hepatitis B vaccination within 24 hours after birth for neonates in Hanoi. Subjects and method: This interventional study was carried out on 163 neonates of positive-HBsAg mothers who were admitted to Hanoi Obstetrical Hospital from 6/2005 to 3/2007. These neonates received anti-HBV immunoglobulin and hepatitis B vaccination within 24 hours after birth, then were followed up for 11 to 18 months. Results: Among these 163 neonates that received interventions, there were 135 neonates that underwent HBsAg tests after 11 to 18 months. The results showed that only one newborn baby had positive HBsAg (0.74%) and 134 neonates with non-HBV (99.26%). 81.5% of neonates had hepatitis B surface antibody that can protect against HBV. Conclusion: Early interventions with anti-HBV immunoglobulin and HBV vaccination were effective in preventing HBV for neonates of positive-HBsAg mothers.

Knowledge and practice on HBV prevention among pregnant women in Hanoi (2005-2006) and some related factors of HBsAg positive rate

Background: hepatitis due to virus B is now one of the leading concerns in the community health care throughout the world. Vietnam was a country located in high risk areas for hepatitis B virus (HBV) infection with rate of HBV infection in the community ranged from 11.3 to 25.5%, the rate of HBsAg positive in pregnant women from 12-16%. Objectives: to evaluate knowledge and practice on HBV prevention among pregnant women in Hanoi in 2005-2006 period; to study on some related factors of HBsAg positive rate. Subjectives and Method: a cross sectional study (with analysis on knowledge and practice about HBV prevention) was carried out on 1.300 pregnant women above 28 gestational weeks at Hanoi Obstetrics/Gynecology Hospital in 2005. Results: the rates of women with knowledge about HBV prevention were 38.5% at good level, 24.4% at acceptable level, and 37.7% at unacceptable level. The rates of practice on HBV prevention were 58.5% at satisfied level and 41.5% at notsatified level. Knowledge was likely related to practice, age, educational level, and HBV positive rate. Practice on HBV prevention was also related to HBV infection. Conclusions: the rates of women with knowledge about HBV prevention at good level were relatively high. The rates of practice on HBV prevention at satisfied level were relatively low. Related factors of HBsAg positive rate: knowledge and practice about HBV prevention.