Incompatibilidad sanguínea por anticuerpos Anti-Duffy (Fya)One female patient with anemia (Hb: 7,4 g/dl) requires transfusions. The cross test results were not compatibles, so they send the case to the National Childrens Hospital in order to carry out the antibodies studies. An anti Fya was found; so she was transfunded with blood Fya (-) without complications. Three compatible units were selected from 20 bloods studied.