Abstract
We were asked to perform an extraction on a patient (29-year-old female) who had been hospitalized at the age of 25 for about 6 months because of shizophreniz, and has been taking phenothiazine derivatives since then. The patient was given a thorough examination because we found an abnormality of activated partial thromboplastin time (APTT) in a laboratory test finding before the extraction.
First, in the mixing test of APTT, the blood plasma of the patient did not normalize even when mixed with normal blood plasma in a 1:1 ratio. In addition, we found no abnormality in coagulation factors of 8, 9, 11, 12.
According to these findings and her medical history, the presence of lupus anticoagulant (LA) was suggested. Therefore the method of dilution prothrombin time (PT) was carried out for the confirmation of L A.
In the result, the P T ratio (dilution PT/ordinary PT) was more than 3.
Finally, we made a diagnosis of L A positive.
After the diagnosis, we proceeded with the extraction as usual. We detected no abnormality during or after the operation.
