Mesude Falay1, Mehmet Senes2, Dogan Yücel2, Turan Turhan3, Simten Dagdaş1, Melike Pekin1, Namik K Nazaroglu4, Gülsüm Özet1. 1. Department of Hematology, Ankara Numune Training and Research Hospital, Ankara, Turkey. 2. Department of Medical Biochemistry, Ankara Training and Research Hospital, Ankara, Turkey. 3. Department of Medical Biochemistry, Ankara Numune Training and Research Hospital, Ankara, Turkey. 4. Synlab Laboratories, Ankara, Turkey.
Abstract
BACKGROUND: This study is a retrospective evaluation of patients who were subject to mixing study in our laboratory due to prolonged APTT. The preliminary diagnoses, clinical manifestations, and results of additional ordered tests were reviewed. The study aims to investigate whether repeating APTT test with a different assay prior to performing mixed study in patients with prolonged APTT would be a better alternative algorithmic approach in order to save both time and costs. METHODS: We retrospectively evaluated 166 patients (65 females and 101 males) who were subject to mixing study due to isolated prolonged APTT. Additional ordered tests to identify the etiology and clinical findings were reviewed. All patients who had prolonged APTT as a result of testing with Hemosil Synthasil APTT reagent in ACL TOP analyzer were repeated with Stago Cephascreen APTT reagent in STA-R coagulation analyzer. RESULTS: APTT test was requested preoperatively in 72.2% of cases. Only 6.6% of the cases had history of bleeding. Correction with mixing study was achieved in 122 (73.5%) cases, among which 75 (45%) cases were found to have APTT test results within reference range when tested with Cephascreen reagent. In 44 (26.5%) cases, mixing study did not result in correction. Only 4 cases were confirmed to have lupus anticoagulants (LA), while 4 cases were diagnosed with hemophilia with inhibitors. CONCLUSION: Prolonged APTT results should always be retested using a different assay prior to mixing study. The clinician and the laboratory specialist should collaborate at the postanalytical phase.
BACKGROUND: This study is a retrospective evaluation of patients who were subject to mixing study in our laboratory due to prolonged APTT. The preliminary diagnoses, clinical manifestations, and results of additional ordered tests were reviewed. The study aims to investigate whether repeating APTT test with a different assay prior to performing mixed study in patients with prolonged APTT would be a better alternative algorithmic approach in order to save both time and costs. METHODS: We retrospectively evaluated 166 patients (65 females and 101 males) who were subject to mixing study due to isolated prolonged APTT. Additional ordered tests to identify the etiology and clinical findings were reviewed. All patients who had prolonged APTT as a result of testing with Hemosil Synthasil APTT reagent in ACL TOP analyzer were repeated with Stago Cephascreen APTT reagent in STA-R coagulation analyzer. RESULTS: APTT test was requested preoperatively in 72.2% of cases. Only 6.6% of the cases had history of bleeding. Correction with mixing study was achieved in 122 (73.5%) cases, among which 75 (45%) cases were found to have APTT test results within reference range when tested with Cephascreen reagent. In 44 (26.5%) cases, mixing study did not result in correction. Only 4 cases were confirmed to have lupus anticoagulants (LA), while 4 cases were diagnosed with hemophilia with inhibitors. CONCLUSION: Prolonged APTT results should always be retested using a different assay prior to mixing study. The clinician and the laboratory specialist should collaborate at the postanalytical phase.
Authors: George A Fritsma; Francine R Dembitzer; Ankush Randhawa; Marisa B Marques; Elizabeth M Van Cott; Dorothy Adcock-Funk; Ellinor I Peerschke Journal: Am J Clin Pathol Date: 2012-06 Impact factor: 2.493
Authors: Éva Ajzner; Dunja Rogic; Piet Meijer; Ann Helen Kristoffersen; Paolo Carraro; Eser Sozmen; Ana Paula Faria; Sverre Sandberg Journal: Clin Chem Lab Med Date: 2015-09-01 Impact factor: 3.694