Transient, selective factor X deficiency and acute liver failure following chest infection treated with erythromycin BP

A 57-year-old man developed symptoms of a respiratory tract infection which was treated with erythromycin BP. He subsequently went into acute liver failure. Investigation of a very prolonged prothrombin time revealed a marked, selective factor X deficiency (1% of normal activity). He later recovered virtually normal liver function and completely normal factor X activity.