Adult patients with the nephrotic syndrome: really at high risk for deep venous thromboembolism? Report of a series and review of the literature.

BACKGROUND

The reported incidence of thromboembolic episodes in people with nephrotic syndrome (NS) ranges from 6% to 44% and it has been ascribed to the presence of a hypercoagulable state, as suggested by abnormalities of several hemostatic parameters in these patients. However, the results of the studies are often contradictory and fragmented and are rarely based on prospective studies. To assess the incidence of venous thrombosis and the pattern of abnormalities of the hemostatic parameters in NS, we planned a prospective study of a group of patients with NS.

PATIENTS AND METHODS

Thirty-six consecutive patients with NS were enrolled during a 9-month period. Every 4-6 months, clinical history was collected and physical examination was carried out. Blood samples for laboratory investigation were taken at entry into the study and 24 months later. A critical review of the literature was also carried out (Medline database and Current Contents).

RESULTS

During the follow-up (mean 45.2 months), no thrombotic symptoms were recorded, PTT, PT, TT and mean AT-III levels were within the normal range, whereas fibrinogen, plasminogen, protein C and S, heparin cofactor II levels were significantly higher than normal both at entry into the study and 24 months later. No patient was positive for antiphospholipid antibodies. Slightly decreased levels of AT-III and heparin cofactor II were found in only two cases.

CONCLUSIONS

Our study confirms neither the high incidence of thrombotic complications in NS nor the presence of abnormalities of hemostatic parameters commonly associated with venous thromboembolism.