RESUMO
BACKGROUND: Continuous lamivudine therapy is associated with high rates of YMDD mutations, which are the main causes of drug resistance. The current study explores the association of the emergence of YMDD mutations with pretherapy HBV genotype, HBV-DNA levels, HBeAg status, and serum alanine aminotransferase (ALT) levels in Chinese patients receiving lamivudine therapy for chronic hepatitis B. METHODS: A total of 319 chronic hepatitis B patients who received lamivudine therapy for more than a year were enrolled in this study. YMDD mutations, HBV genotype, HBV-DNA levels, HBeAg status, and ALT levels were determined prior to their lamivudine treatment and every three months for a year of this therapy. RESULTS: Among the 319 patients, 137 (42.95%) were infected with genotype B and 182 (57.05%) with genotype C. Up to 94 patients (29.47%) developed YMDD mutations within one year of lamivudine therapy. Furthermore, 50 patients with HBV genotype B and 44 patients with genotype C developed YMDD mutations (36.50% vs 24.18%, P<0.05). Logistic regression analysis showed that pretherapy HBV genotype, HBV-DNA levels, and HBeAg status are independent factors for the emergence of YMDD mutations (HBV genotype: OR=2.159, 95% CI 1.291-3.609, P=0.003; HBV-DNA: OR=1.653, 95% CI 1.231-2.218, P=0.001; HBeAg: OR=2.021, 95% CI 1.201-3.399, P=0.008). CONCLUSIONS: HBV genotype, HBV-DNA levels, and HBeAg status at baseline are the independent factors associated with the emergence of YMDD mutations among Chinese patients receiving lamivudine therapy for chronic hepatitis B. These findings are helpful to the development of therapeutic strategies for these patients.
Assuntos
Aminoácidos/genética , DNA Viral/sangue , DNA Viral/genética , Genótipo , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Mutação/genética , Adulto , Idoso , Alanina Transaminase/sangue , Antivirais/uso terapêutico , Ácido Aspártico/genética , China , Farmacorresistência Viral/genética , Feminino , Hepatite B Crônica/sangue , Hepatite B Crônica/genética , Humanos , Isoleucina/genética , Modelos Logísticos , Masculino , Metionina/genética , Pessoa de Meia-Idade , Estudos Retrospectivos , Tirosina/genética , Valina/genéticaRESUMO
OBJECTIVE: To investigate the prevalence of aminoglycoside resistance and genotyping of acetyltransferase in Escherichia coli. METHODS: Resistance phenotypes to 12 antibiotics of 44 Escherichia coli isolates were analyzed using agar dilution method and 3 aminoglycoside resistance genes aac(3)-I, II and aac(6')-I were determined by PCR method. RESULTS: In 44 clinical isolates, the occurrence of ESBLs was 45.45%, resistance rates were discrepant for amikacin (18.18%), gentamicin (56.82%) and tobramycin (61.36%), the prevalence of phenotype TG (tobramycin and gentamicin) indicative of aac(3)-II production and TGA (tobramycin, gentamicin and amikacin) indicative of aac(6')-I production were 36.36% and 18.18%, respectively. The most common aminoglycoside resistance genotype of acetyltransferase was aac(3)-II (52.27%) and aac(6')-I was lower (29.55%), but no aac(3)-I was detected. CONCLUSION: At least 2 acetyltransferase genes exist in this area i.e. aac(3)-II and aac(6')-I.
