Diagnosis of septic pelvic thrombophlebitis by measurement of fibrinopeptide A.

Septic pelvic thrombophlebitis is an uncommon but potentially life-threatening complication of puerperal endometritis. The lack of specific physical findings necessitates a diagnosis based by exclusion on the patient's response to anticoagulation. Fibrinopeptide A (FPA) is the first peptide cleaved from fibrinogen during thrombin-mediated fibrin generation. Because of its short half-life, FPA accurately reflects the level of ongoing fibrin generation. In a preliminary study of 40 puerperal patients, FPA successfully differentiated puerperal fever secondary to endometritis or abscess from fever responsive to a heparin trial. The mean FPA level in patients presumed to have septic pelvic thrombophlebitis was 23.8 ng/ml as opposed to 7 ng/ml in patients with endometritis. No patient with septic pelvic thrombophlebitis as diagnosed by her response to a heparin trial had a level of FPA less than 14 ng/ml. There was no overlap of FPA levels between patients with endometritis or abscess and septic pelvic thrombophlebitis. The data suggest further prospective evaluation of FPA for the diagnosis of septic pelvic thrombophlebitis is warranted.