If you have additional symptoms or laboratory findings such as those listed below, then you should be tested for aPL: unexplained blood clots, low platelet counts, miscarriages, another systemic autoimmune disease such as lupus, abnormal results in an activated partial thromboplastin time (aPTT) screening test, skin findings that are fixed and do not improve with rewarming, development of bruise-like areas or ulcers associated with the livedo findings.