Transcription-mediated amplification is more useful in the follow-up of patients with chronic hepatitis B treated with lamivudine

Changes in the HBV DNA level during the treatment of patients with chronic hepatitis B with lamivudine were investigated by the transcription-mediated amplification (TMA) assay. Twenty-four patients treated with lamivudine (m ales:female = 20:4, age: 44.0 +/- 9.0 years, chronic hepatitis: 14. cirrhos is: 7, cirrhosis with hepatocellular carcinoma: 3) were investigated. The d osage of lamivudine was 75 mg/day in 3, 100 mg/day in 8, and 150 mg/day in 13 patients. and the administration period was 48 +/- 16 weeks (24-79 weeks ). Sixteen patients were HBe antigen-positive before treatment, and the HBV DNA level was 7.4 +/- 1.2 (4.0-more than 8.7) LGE/ml. The HBV DNA level wa s measured every 1-6 months by the TMA assay and the branched DNA signal am plification technology (b-DNA assay). Serum HBV DNA disappeared in all pati ents by the b-DNA during the treatment period, while six patients had persi stent HBV DNA by the TMA. The time of HBV DNA disappearance by the TMA in 1 8 patients was 2-5 months after initiation of treatment. The disappearance rate of HBV DNA was 3/8 (38%) in patients whose HBV DNA level before treatm ent was 8.0 LGE/ml or higher, 7/8 (88%) in those with 7-7.9 LGE/ml. and 8/8 (100%) in those with 6.9 LGE/ml or lower, showing that disappearance of HB V DNA became difficult when the HBV DNA level before treatment was high (P< 0.01). In six patients. the HBV DNA level disappeared once, then increased thereafter. The present findings suggested that these increases in the HBV DNA level were due to an increase of YMDD mutant in three of these six pati ents, and due to a decrease in the dosage in two patients. In treatment wit h lamivudine, the TMA assay is more useful for understanding the changes in the HBV DNA level than b-DNA assay. (C) 2001 Elsevier Science B.V. All rig hts reserved.