This paper presents a case of an 80-year-old man with idiopathic thrombocytopenic purpura after splenectomy performed many years ago, which normalized platelet count, presented with severe thrombocytopenia with no response to treatment. A SPECT/CT study was performed using 99mTc-labelled Sn-colloid. The histology confirmed the presence of splenic tissue in those foci. Spleen examination (SPECT/CT) using 99mTc-labelled Sn-colloid is able to detect splenic tissue and in our opinion is a simpler and less time-consuming procedure than using 99mTc DRBC.