Electromyography

Studies from Pusan National University have provided new data on hepatitis B virus

"The lack of cytotoxicity and absence of an effect on mitochondrial function have been considered the reasons for the fewer adverse events. However, it came to our attention that several hepatitis B patients developed myopathy during clevudine therapy. Our study was aimed to analyze the clinical and pathological features of patients with clevudine-induced myopathy with some consideration of its pathogenetic mechanism. Seven hepatitis B patients who developed severe skeletal myopathy during clevudine therapy were examined in this study. The demographic data, clinical features, pathological findings, and molecular studies of these patients were analyzed with speculation about the underlying pathogenic mechanisms. All seven patients were treated with clevudine for more than 8 months (8-13 months). In all, the main symptom was slowly progressive proximal muscular weakness over several months. A markedly elevated creatine kinase level and myopathic patterns on electromyography were found. Muscle biopsies revealed severe myonecrosis associated with numerous ragged red fibers, cytochrome c oxidase-negative fibers, and predominant type 11 fiber atrophy. Molecular studies using quantitative polymerase chain reaction showed a depletion of the mitochondrial DNA in the patients' skeletal muscle," wrote J.I. Seok and colleagues, Pusan National University.

The researchers concluded: "To the best of our knowledge, this is the first report of myopathy associated with clevudine therapy. This study has clearly shown that long-term clevudine therapy can induce the depletion of mitochondrial DNA and lead to mitochondrial myopathy associated with myonecrosis. Careful clinical and laboratory attention should be paid to patients on long-term clevudine therapy for this skeletal muscle dysfunction. (HEPATOLOGY 2009; 49:2080-2086.)'."

Seok and colleagues published their study in Hepatology (Long-Term Therapy with Clevudine for Chronic Hepatitis B Can Be Associated with Myopathy Characterized by Depletion of Mitochondrial DNA. Hepatology, 2009;49(6):2080-2086).

For additional information, contact D.S. Kim, Pusan National University, Yangsan Hospital, Dept. of Neurology, Yangsan 626770, Gyeongsangnam D, South Korea.

The publisher's contact information for the journal Hepatology is: John Wiley & Sons Inc., 111 River St., Hoboken, NJ 07030, USA.

Keywords: South Korea, Adverse Drug Effect, Adverse Drug Event, Adverse Drug Reaction, Antiviral Activity, Chronic Hepatitis B, Clinical Trial Research, DNA, Gastroenterology, HBV, Hepatitis B Virus, Hepatology, Infectious Disease, Myopathy, Nucleoside Analog, Therapy, Treatment, Viral Inhibition, Viral Therapy, Virology, Pusan National University.

This article was prepared by Pain & Central Nervous System Week editors from staff and other reports. Copyright 2009, Pain & Central Nervous System Week via NewsRx.com.