Livedo vasculitis: vasculitis or thrombotic vasculopathy?

Elevated fibrinopeptide A levels, suggestive of a thrombogenic state, were observed in six patients with livedo vasculitis. Serological studies demonstrated normal complement levels, and circulating immune complexes were not identified by standard assays. Morphological studies showed no evidence of immune complex deposition or a neutrophilic vascular reaction.

Heparin dosing and monitoring for cardiopulmonary bypass. A comparison of techniques with measurement of subclinical plasma coagulation.

Subclinical plasma coagulation during cardiopulmonary bypass has been associated with marked platelet and clotting factor consumption in monkeys. To better define subclinical coagulation in man, we measured plasma fibrinopeptide A concentrations before, during, and after cardiopulmonary bypass. Patients were assigned to one of three groups of heparin management: group 1 (n = 10)--initial heparin dose 300 IU/kg, with supplemental heparin if the activated coagulation time fell below 400 seconds; group 2 (n = 6)--initial heparin dose 250 IU/kg, with supplemental heparin if activated coagulation time was less than 400 seconds; and group 3 (n = 5)--initial heparin dose 350 to 400 IU/kg, with supplemental heparin if whole blood heparin concentration was less than or equal to 4.

Clinical significance of combined antinuclear and anticytoplasmic antibodies detected by immunofluorescence.

Anti-nuclear antibodies (ANA) combined with anti-cytoplasmic antibodies (ACA) in 0.6% (n = 43) of 7,121 consecutive patients referred for ANA screening were observed. Homogeneous/cytoplasmic was the most frequently combined ANA/ACA pattern among 6 different indirect immunofluorescent (IF) combinations.

Initiation of the extrinsic pathway of coagulation by human and rabbit alveolar macrophages: a kinetic study.

We examined assembly and expression of the factor X activating complex on human and rabbit alveolar macrophages. Kinetic parameters of the factor X activating reaction were determined by functional titrations of factors VII and X with macrophage tissue factor (TF) added. We found rapid activation of factor X to Xa on alveolar macrophage surfaces.

Anticardiolipin antibody: a marker of immune reactivity.

An enzyme-linked immunosorbent assay for anticardiolipin (ACL) antibody was performed on 250 consecutive antinuclear antibody (ANA) or anticytoplasmic antibody (ACA) positive sera and 50 consecutive ANA/ACA negative sera submitted to a rheumatology reference laboratory for ANA testing. Of the 250 ANA/ACA positive sera, 33 (13%) were found to be ACL antibody positive. This compared with only 2 (4%) ACL antibody positive samples among the 50 ANA/ACA negative controls.