Rhabdomyolysis and elevated liver function tests-what's the underlying cause?

A 71-year-old man with a past history of carcinoma of the prostate was admitted in August 2011, feeling unwell and with new-onset weakness of the quadriceps muscles for the past 2 days. He had initially received a diagnosis of adenocarcinoma of the prostate in May 2011 and he had been treated with cyproterone acetate 300 mg since June 2011. He had also been on aspirin 75 mg and simvastatin 40 mg unchanged for the past 2 years. On admission, here, he appeared unwell but normotensive and afebrile. He had weakness of his lower limbs (power 2/5) with normal reflexes. Serum creatinine was 338 lmol/L and liver function tests were also markedly abnormal [alanine transaminase 887 U/L (normal < 41 U/L), c-glutamyltransferase 111 U/L (normal < 41 U/L)]. Previous serum creatinine results and liver function were all normal. Urine dipstick was positive for blood but urine microscopy was negative. Ultrasound showed normal sized kidneys and normal liver parenchyma. The creatine kinase was 78820 U/L. A complete virology and immunology screen, including Jo-1 antibodies, was negative.