Entecavir-associated myopathy: a case report and literature review.
BACKGROUND
Entecavir, a nucleoside analog (NA), is effective for treatment of chronic hepatitis B virus (HBV) infection.


METHODS
We report the case of a patient we encountered with entecavir-associated myopathy. We also performed a literature review of myopathies associated with nucleoside analogs.


RESULTS
A 44-year-old man presented with a 3-month history of myalgia and progressive weakness. He had HBV infection and had received entecavir antiviral treatment for 5 years. Laboratory tests showed that serum creatine kinase levels were significantly elevated. Muscle histopathology showed abundant T-lymphocyte infiltration of muscle fibers, and HBV surface antigen and HBV core antigen were not present in muscle fibers. Entecavir-associated myopathy was subsequently diagnosed. The patient's symptoms eventually resolved, and serum CK levels decreased rapidly after he stopped receiving entecavir treatments.


CONCLUSIONS
Patients who receive NA therapy should be closely monitored for myopathic side effects. Muscle Nerve 49:610-614, 2014.
Department of Rheumatology, China-Japan Friendship Hospital, Yinghua East Road, Chaoyang District, Beijing, 100029, China.
Kai
K
Yuan
Wang
W
Guochun
Zhenguo
Z
Huang
Bing
B
Lin
Huiqiong
H
Zhou
Xin
X
Lu
D000328:Adult; D000998:Antiviral Agents / Q000009:adverse effects*; D006147:Guanine / Q000009:adverse effects / Q000031:analogs & derivatives*; D006801:Humans; D008297:Male; D018908:Muscle Weakness / Q000139:chemically induced / Q000175:diagnosis; D009135:Muscular Diseases / Q000139:chemically induced* / Q000175:diagnosis*
D000998:Antiviral Agents; C413685:entecavir; D006147:Guanine
creatine kinase; entecavir; hepatitis B; myopathy; nucleoside analog