Recurrent meningococcal septicaemia and properdin deficiency

A 32-year-old male presented with two episodes of meningococcal septicaemia, each of which was caused by a different serogroup of Neisseria meningitidis . Examination of the alternative pathway of complement revealed the rare X-linked disorder properdin deficiency (PD). Meningococcal infection in complement deficiency states is discussed and the unusual features of this case are highlighted.