S. Hoare, O. El-Shazali, A. Fay, A.J. Cant
Paediatric Infectious Diseases Unit, Newcastle General Hospital, Newcastle upon
Tyne
Meningococcal disease (MCD) may be associated with abnormalities of the complement system. Though rare these disorders have major ramifications for management. Three major paediatric textbooks recommend the routine measurement of complement levels post-MCD. Is a selective policy for screening more appropriate for children in the UK?
From 1996-99 surviving children with a diagnosis of MCD (based on clinical findings, course of disease or culture and non-culture methods) were reviewed 6-8 weeks following their discharge from hospital when CH100 and AP100 measured. These are gel assays dependent upon 100% haemolysis and measure the integrity of the classical and alternate pathways of complement activation. If CH100/AP100 were absent, additional tests were done to identify the missing complement components. 212 children, aged 2mo. – 16 yrs., were screened. 33% had required admission to the Paediatric Intensive Care Unit. All but one were due to group B and C disease. Only 1 child was complement-deficient. She presented age 4yrs. with group B meningococcal septicaemic shock with DIC, requiring ventilation and inotrope support. However she also had a previous history of pneumococcal meningitis and septicaemia age 4 mo., with raised intracranial pressure and focal fits. On follow up, whilst AP100 was normal, CH100 was absent. C2 deficiency was subsequently confirmed. She has no clinical evidence of autoimmune disease and autoantibodies have been normal. Family studies revealed no other affected members.
CONCLUSIONS: It is unnecessary to screen all children routinely following MCD if due to common serogroups. However it is important to assess the previous health of the child and to investigate appropriately if there have been previous suspicious infections, abnormal course of infective illnesses, if infection is due to unusual serogroups, or if this is a repeated episode of Neisserial infection.