Following thorascopic thymectomy performed because of myasthenia gravis, a 25-year-old man was affected by fulminant hepatic failure (FHF) of unknown etiology. He was then transferred to our department, where his clinical situation worsened with the onset of renal failure, shock, coagulopathy and coma. Given the young age of the patient, the immediate availability of a donor, and the absence of a definite diagnosis of sepsis at the time, it was decided to proceed with liver transplantation. The results of a polymerase chain reaction (PCR) test (a technique that was unavailable at the referring hospital), which arrived only a few hours later, indicated the presence of herpes simplex virus (HSV) DNA in several of the patient's samples; this led to the formulation of a diagnosis of FHF due to HSV It is worth noting that HSV-IgM and HSV-IgG assays had always been negative in this patient. Despite acyclovir therapy with initially encouraging clinical results, the patient died several days later because the viral infection had spread to the graft, lungs, heart, spleen, stomach and kidneys. Since evaluating antibody response is not always useful in diagnosing HSV infection, and particularly if PCR methodology is unavailable, it is worth initiating early empiric antiviral therapy when the etiology of FHF is indeterminate This is because the timeliness of treatment while awaiting virological confirmation may be critical to survival. If a liver transplantation becomes mandatory, careful consideration should be given to the extent of the viral infection and its response to therapy because of the possibility of viral spread to the graft.
