Can lupus anticoagulant be positive despite a normal aPTT?

aPTT is one of the assays that may be abnormal in the presence of lupus anticoagulant, but not always. Usually, when screening for lupus anticoagulant, there will be a "special" aPTT assay used that is a bit more sensitive to detect lupus anticoagulant. There are several different aPTT-based assays ...