APTT ndi chidule cha Chingerezi cha nthawi ya prothrombin yomwe yayamba kugwira ntchito pang'ono. APTT ndi mayeso owunikira omwe akuwonetsa njira yolumikizirana ya endogenous. APTT yayitali imasonyeza kuti chinthu china cholumikizirana cha magazi chomwe chimakhudzidwa ndi njira yolumikizirana ya endogenous ya anthu sichigwira ntchito bwino. APTT ikatalikitsidwa, wodwalayo adzakhala ndi zizindikiro zoonekeratu za kutuluka magazi. Mwachitsanzo, odwala omwe ali ndi hemophilia A, hemophilia B, ndi matenda a von Willebrand onse adzakhala ndi APTT yayitali, ndipo wodwalayo adzakhala ndi ecchymosis pakhungu ndi mucous membranes, komanso kutuluka magazi m'minofu, kutuluka magazi m'mafupa, hematoma, ndi zina zotero. Makamaka kwa odwala omwe ali ndi hemophilia A, zolakwika za mafupa ndi minofu nthawi zambiri zimasiyidwa hematoma ikalowa chifukwa cha synovitis yomwe imayambitsidwa ndi kutuluka magazi m'mafupa, zomwe zimakhudza kwambiri thanzi. Kuphatikiza apo, kufalikira kwa magazi m'mitsempha, matenda oopsa a chiwindi ndi matenda ena angayambitsenso kutalikitsa kwa APTT, komwe kungayambitse kuvulaza thupi la munthu.
Kuchuluka kwa Aptt kumasonyeza kuti wodwalayo akhoza kudwala matenda otuluka magazi. Matenda ofala kwambiri otuluka magazi ndi monga kusowa kwa congenital coagulation factor ndi hemophilia. Kachiwiri, akuganiziridwa kuti amayamba chifukwa cha matenda a chiwindi kapena obstructive jaundice kapena matenda a thrombotic. Sizikudziwikanso kuti amayamba chifukwa cha mphamvu ya mankhwala, monga kugwiritsa ntchito mankhwala oletsa magazi kwa nthawi yayitali. Mwachipatala, mayeso a aptt angagwiritsidwe ntchito kuweruza ngati ntchito ya coagulation m'thupi la wodwalayo ndi yachibadwa. Ngati ndi chifukwa cha vuto lomwe limabwera chifukwa cha hemophilia, tikulimbikitsidwa kutsatira upangiri wa dokotala kuti asiye kutuluka magazi kapena kugwiritsa ntchito mankhwala a prothrombin complex.