As he was thought to have anemia of chronic disease based on iron studies at OSH, possible renal contribution so he received erythropoeitin.
 He received erythropoeitin to treat his anemia
(ROOT (FRAG (SBAR (IN As) (S (NP (PRP he)) (VP (VBD was) (VP (VBN thought) (S (VP (TO to) (VP (VB have) (NP (NP (NN anemia)) (PP (IN of) (NP (JJ chronic) (NN disease)))) (PP (VBN based) (PP (IN on) (NP (NN iron) (NNS studies)))) (PP (IN at) (NP (NNP OSH)))))))))) (, ,) (NP (NP (JJ possible) (JJ renal) (NN contribution)) (SBAR (IN so) (S (NP (PRP he)) (VP (VBD received) (NP (NN erythropoeitin)))))) (. .)))
(ROOT (S (NP (PRP He)) (VP (VBD received) (S (NP (NN erythropoeitin)) (VP (TO to) (VP (VB treat) (NP (PRP$ his) (NN anemia))))))))
( ( As ( he ( was ( thought ( to ( ( ( have ( anemia ( of ( chronic disease ) ) ) ) ( based ( on ( iron studies ) ) ) ) ( at OSH ) ) ) ) ) ) ) ( , ( ( ( possible ( renal contribution ) ) ( so ( he ( received erythropoeitin ) ) ) ) . ) ) )
( He ( received ( erythropoeitin ( to ( treat ( his anemia ) ) ) ) ) )