Summary
Patients with severe meningococcal infection are characterized by extensive microvascular
thrombosis, consumption coagulopathy and secondary hemorrhages. The contribution of
the inherited prethrombotic disorders to the severity of the disease course is not
established yet. Here, we report on the levels of protein C, protein S, antithrombin
and the presence of the factor V Leiden mutation (R506Q) in 50 patients with meningococcal
disease, as determined 6 to 58 months after hospital discharge. In addition, we recalled
the parents of 16 deceased patients to screen for the mutation in factor V, an abnormality
which results in resistance to activated protein C. Among the patients, the prevalence
of the genetic risk factors for thrombosis was not higher than expected on the basis
of their prevalence in the general population. Moreover, the prevalence of the factor
V Leiden mutation was not increased among the parents of the deceased patients. The
individual plasma levels of protein C, protein S, and antithrombin did not differ
between the patients with or without severe purpura. The present data constitute circumstantial
evidence that primary defects in the natural anticoagulant systems do not play a major
role in the severity of the disease course. Screening of patients with infectious
purpura for inherited thrombotic risk factors is therefore not indicated.