A 52-year-old Caucasian woman presented to the emergency department with symptoms of acute ischaemic stroke (right-side weakness, confusion and aphasia) that resolved completely after administration of tissue plasminogen activator. During stroke work-up, she was found to have an enhancing infiltrate of the aorta at the level of the take-off of the great vessels, most consistent with early Takayasu arteritis. After being discharged home on steroids and dual antiplatelet therapy, she returned 2 days later with re-presentation of weakness and aphasia. Further work-up revealed two intraluminal clots in the left common carotid and left internal carotid arteries that had not been discovered during previous testing. This case illustrates the need to screen for sources of embolic stroke in patients with Takayasu arteritis, especially those with recurring symptoms.

Thrombotic diseases have been shown to increase in the winter. This study sought to examine four thrombotic factors; Fibrinogen (Fb), Factor VII (FVII), Factor X (FX) and Tissue Plasminogen Activator Inhibitor (TPA‐I), and two thrombolytic factors Antithrombin III (ATIII) and Tissue Plasminogen Activator (TPA) in human plasma during winter and summer. To date, no comprehensive studies exist that look at these clotting factors simultaneously. Sandwich ELISA was used to measure the concentration of each factor from individual subjects. Statistical significance was found in seasonal variation of Fb, FVII, FX and TPA‐I (limited to females). A lower concentration of Fibrinogen was found in the winter, which was unexpected, but consistent with other studies. FVII increased in the winter, consistent with our original hypothesis. FX showed lower concentrations in the winter, which has not been previously reported in the literature. TPA‐I showed a marked increase in the summer but this increase was limited to females over 40. Neither TPA, nor ATIII showed significant seasonal variation. We conclude from this that a number of thrombotic factors increase in the winter but this is not consistent among all factors measured. Thrombolytic factors were unchanged. This research was supported by the Saint Mary's College of California Faculty‐Alumni Grant, Faculty Development Grant, and the Summer Research Program

Increasing thrombotic disease is seen in the aging population, with reported differences by sex. This study sought to examine thrombotic and thrombolytic factors in human plasma while controlling for age and sex. Subjects ranged from 25–69 yr of age. Thrombotic factors; Fibrinogen (Fb), Factor VII (FVII), Factor X (FX), Tissue Plasminogen Activator Inhibitor (TPA‐I)) and thrombolytic factors; Tissue Plasminogen Activator (TPA) and Antithrombin III (ATIII) were analyzed using sandwich ELISA. Our results show a significant increase in FVII with age in women, with no difference in males. TPA‐I rises in females at perimenopause and remains elevated in menopause. Fb in males is significantly elevated in youngest and oldest groups. TPA‐I was markedly increased in the youngest males only. FX showed a sharp and linear decrease with age in males but not females. We conclude that the rise in clotting factors, Fb in males and FVII and TPA‐I in females may influence increased thromboembolic disease with aging. FX findings suggest that not all factors that are thrombotic play a role in increased thromboembolic disease with aging. The two thrombolytic factors had no significant variation in any experimental group. This research was supported by the Saint Mary's College of California Faculty‐Alumni Grant, Faculty Development Grant, and the Summer Research Program.