A case of meningococcal sepsis and meningitis with complement 7 deficiency in a military trainee

Complement component 7 (C7) deficiency leads to the loss of complement lytic function, and affected patients show increased susceptibility to encapsulated organisms infection, especially Neisseria meningitidis. Recently, we have experienced a 20-year-old military trainee with meningococcal sepsis and meningitis who was diagnosed as having C7 deficiency based upon the undetectable serum C7 protein on radioimmunoassay. This case emphasizes that although C7 deficiency is rare immune disorder, it is important to be aware of possibility about late complement deficiency among patients who present with meningococcal disease.