Protein S deficiency is one of the principal congenital thrombophilias reported. The objective of this study was to assess the prevalence of protein S deficiency in patients with repetitive superficial thrombophlebitis. Thirty-six consecutive patients, 28 female and eight male, who presented with repetitive superficial thrombophlebitis (two or more cases); age range, 17 to 58 years, mean, 38.2 years; were evaluated. Coagulometry was used to determine the biologic activity of protein S. In 5.5% of the patients with repetitive superficial thrombophlebitis, protein S deficiency was detected.
