▁imm un olog ically - medi ated ▁hem ol yt ic ▁an em ias ▁and ▁in ▁her edit ary ▁spher oc yt osis , ▁but ▁the ▁former ▁would ▁have ▁a ▁positive ▁direct ▁Co omb s ▁test ▁and ▁the ▁latter ▁would ▁not . ▁ ▁The ▁miss h ap en ▁but ▁otherwise ▁health y ▁red ▁blood ▁cells ▁are ▁mistaken ▁by ▁the ▁s ple en ▁for ▁old ▁or ▁dam aged ▁red ▁blood ▁cells ▁and ▁it ▁thus ▁constantly ▁breaks ▁them ▁down , ▁causing ▁a ▁cycle ▁where by ▁the ▁body ▁dest ro ys ▁its ▁own ▁blood ▁supply ▁( auto - hem ol ysis ). ▁A ▁complete ▁blood ▁count ▁( C BC ) ▁may ▁show ▁increased ▁ret icul ocy tes , ▁a ▁sign ▁of ▁increased ▁red ▁blood ▁cell ▁production , ▁and ▁decre ased ▁hem og lo bin ▁and ▁h emat oc rit . ▁The ▁term ▁" non - her edit ary ▁spher oc yt osis " ▁is ▁occasionally ▁used , ▁al beit ▁rarely . ▁ ▁List s ▁of ▁causes : ▁W arm ▁auto imm une ▁hem ol yt ic ▁an emia ▁Cold ▁auto imm une ▁hem ol yt ic ▁an emia / par ox ys mal ▁cold ▁hem og lo bin uria ▁Ac ute ▁and ▁delayed ▁hem ol yt ic ▁trans f usion ▁re actions ▁A BO ▁hem ol yt ic ▁dise ases ▁of ▁new born / R h ▁hem ol yt ic ▁disease ▁of ▁new born ▁Her edit ary ▁spher oc yt osis ▁In tra ven ous ▁water ▁inf usion ▁or ▁d row ning ▁( f resh ▁water