Ha Manh Tuan

Managing chronic hepatitis B in children presents significant challenges, particularly due to the risk of antiviral resistance with prolonged lamivudine use. We report 3 pediatric cases in Vietnam who experienced virologic breakthrough after lamivudine therapy failure. Genotypic testing of the hepatitis B virus polymerase gene revealed resistance mutations: M204V/I in all 3 cases, L180M in 2 cases (cases 2 and 3), L80I in case 1, and M250L in case 2. After resistance was identified, switching to tenofovir disoproxil fumarate achieved complete viral suppression, whereas switching to entecavir resulted in a partial yet clinically meaningful virologic response, due to cross-resistance conferred by the M204V/I mutations. These cases provide clinical observations from a resource-limited setting, suggesting that tenofovir disoproxil fumarate may be preferable to entecavir for salvage therapy following lamivudine failure. This emphasizes the urgent need for accessible genotypic testing to guide treatment decisions and prevent the use of ineffective sequential monotherapies.

Background: The research aimed to increase certain HbA1c concentrations at medical decision levels for external quality control samples from healthy donor blood. Methods: The in vitro study was performed from October 2019 to January 2021 at Quality Control Center for Medical Laboratory at University of Medicine and Pharmacy at Ho Chi Minh City. The study observed on the conditions including the optimal buffer solutions (BAGPM, BPS, Ringer, Saline), temperature (2ºC - 8ºC, 22ºC - 24ºC, 37ºC), and glucose concentration (100 mM, 305 mM, 500 mM) affecting the HbA1c concentration in vitro to make the external quality control samples fell in normal, prediabetes, and diabetes range. At every condition, the HbA1c concentration was measured by Tina Quant method to look for the optimal procedure to increase HbA1c concentration required of the external quality control protocol. Results: The highest HbA1c concentration (11.57±0.2%) was found in BAGPM solution with 100 mM glucose after 15 days with the baseline HbA1c 5.43±0.13%; the HbA1c level increase dramatically at 37ºC in BAGPM 500 mM glucose solution in fifteen days (40.03±1.05%). Conclusions: The appropriate conditions were identified to prepare HbA1c standards for prediabetic and diabetic levels. The standards for HbA1c concentrations were recommended to prepare by incubating RBCs from non-diabetic donor blood in BAGPM solution containing glucose at 37ºC for 24 hours. Glucose concentrations should be 100 mM and 500 mM, respectively, for prediabetic level (HbA1c ~ 6.0 ± 0.12%) and diabetic level (HbA1c ~ 9.6 ± 0.17%).

The aim of this study was to investigate genetic structures and expression of bla OXA-58 gene in five Acinetobacter baumannii clinical isolates recovered from two hospitals in southern Vietnam during 2012-2014. A. baumannii isolates were identified by automated microbiology systems and confirmed by PCR. All isolates were characterized as multidrug resistant by antimicrobials testing using the disk diffusion method. Four imipenem susceptible and one non-susceptible isolates (MIC > 32 μ g.ml ⁻¹ ) were identified by E-test. PCR amplification of bla _OXA-58 gene upstream and downstream sequences revealed the presence of IS Aba3 at both locations in one multidrug resistant isolate. Semi quantitation of bla _OXA-51 and bla _OXA-58 gene expression was performed by the 2 ^−ΔΔCt method. The bla _OXA-51 gene expression of five isolates showed little difference but the isolate bearing IS Aba3-bla _OXA-58 -IS Aba3 exhibited significant higher bla _OXA-58 mRNA level. Higher β-lactamases activity in periplasmic than cytoplasmic fraction was found in most isolates. The isolate overexpressing bla OXA-58 gene possessed very high periplasmic enzyme activity. In conclusion, the A. baumannii isolate bearing IS Aba3-bla _OXA-58 gene exhibited high resistance to imipenem, corresponding to an overexpression of bla _OXA-58 gene and very high periplasmic β-lactamases activity.

Hand, foot and mouth disease (HFMD) is an emerging infection with pandemic potential. Knowledge of neutralizing antibody responses among its pathogens is essential to inform vaccine development and epidemiologic research. We used 120 paired-plasma samples collected at enrollment and >7 days after the onset of illness from HFMD patients infected with enterovirus A71 (EV-A71), coxsackievirus A (CVA) 6, CVA10, and CVA16 to study cross neutralization. For homotypic viruses, seropositivity increased from <60% at enrollment to 97%–100% at follow-up, corresponding to seroconversion rates of 57%–93%. Seroconversion for heterotypic viruses was recorded in only 3%–23% of patients. All plasma samples from patients infected with EV-A71 subgenogroup B5 could neutralize the emerging EV-A71 subgenogroup C4. Collectively, our results support previous reports about the potential benefit of EV-A71 vaccine but highlight the necessity of multivalent vaccines to control HFMD.

The aim of this study was to investigate genetic structures and expression of bla_OXA-58 gene in five Acinetobacter baumannii clinical isolates recovered from two hospitals in southern Vietnam during 2012‐2014. A. baumannii isolates were identified by automated microbiology systems and confirmed by PCR. All isolates were characterized as multidrug resistant by antimicrobial testing using the disk diffusion method. Four imipenem susceptible and one nonsusceptible isolates (MIC > 32 μg·ml^-1) were identified by E‐test. PCR amplification of bla_OXA-58 gene upstream and downstream sequences revealed the presence of ISAba3 at both locations in one multidrug‐resistant isolate. Semiquantitation of bla_OXA-51 and bla_OXA-58 gene expression was performed by the 2^-ΔΔCt method. The bla_OXA-51 gene expression of five isolates showed little difference, but the isolate bearing ISAba3‐bla_OXA-58‐ISAba3 exhibited significantly higher bla_OXA-58 mRNA level. Higher β‐lactamases activity in periplasmic than cytoplasmic fraction was found in most isolates. The isolate overexpressing bla_OXA-58 gene possessed very high periplasmic enzyme activity. In conclusion, the A. baumannii isolate bearing ISAba3‐bla_OXA-58 gene exhibited high resistance to imipenem, corresponding to an overexpression of bla_OXA-58 gene and very high periplasmic β‐lactamase activity.

We investigated enterovirus A71-associated hand, foot and mouth disease in Vietnam and found that, after replacing subgenogroup C4 in 2013, B5 remained the leading cause of this disease. In contrast with previous observations, this switch did not result in an explosive outbreak, and B5 evolution was driven by negative selection.

Purpose: The purpose of this paper is to validate measures of professional self-efficacy for detecting and responding to child abuse and neglect presentations, and then evaluate a clinical training programme for health professionals in a tertiary-level hospital in Vietnam. Design/methodology/approach: A prospective, cohort design was used and professional self-efficacy was measured immediately prior to, and shortly after, training 116 nurses and doctors in emergency settings. Longer-term follow-up was measured six months later. Findings: Linear mixed modelling showed that there was a statistically significant improvement in efficacy expectations for both suspected and known cases of child abuse and neglect between the pre- and post-test measures at zero and six weeks. These improvements did not persist to the six-month follow-up. Research limitations/implications: The training succeeded in improving detection and clinical response to child abuse and neglect presentations but not faith in the provision of ongoing support for children and families. Practical implications: Practice change in emergency settings in Vietnam can be achieved using a sustainable theoretically driven training programme. Social implications: Building the capacity of health professionals to respond to cases of child abuse and neglect relies on the strength of the community and support services within which the hospital is located. Originality/value: Measures of self-efficacy expectations and outcome expectations for responding to child abuse and neglect presentations in emergency settings in Vietnam are now validated.