Refractory humoral cardiac allograft rejection successfully treated with a single dose of rituximab. 
Despite improvements in immunosuppression over the last two decades, the risk of allograft rejection is still high in the early postoperative period.  Cellular rejection accounts for the majority of these episodes.  However, humoral rejection is a distinct phenomenon that carries a high rate of graft loss and mortality.  The currently available treatments for this serious clinical problem include anti-lymphocyte antibodies, immune globulin infusions, as well as plasmapheresis, all of which have limitations.  We describe a case of refractory humoral cardiac rejection successfully treated with a single dose of rituximab (375 mg/m2).  No further episodes occurred with 2 years of follow-up.