gms | German Medical Science

Introduction: Invasive meningococcal infections are an uncommon but redoubtable cause of sepsis. In 2009, the incidence amounted to 493 cases in Germany (0.6/100,000) with an overall mortality of 8%. The disease pattern ranges from overwhelming sepsis to purulent meningitis and nearly asymptomatic bacteraemia. The understanding for these differences still is rudimentary, even though a multitude of information is available about virulence factors of the pathogen and specific causes for host susceptibility.

Objectives: The aim of our network is to aggregate and combine information about molecular epidemiology and strain-specific virulence factors with disease severity and risk factors for host susceptibility, in order to explain the different disease courses and outcomes.

Methods: Since 2008 we record nationwide all cases of invasive meningococcal disease in children and adolescents by a voluntary reporting system where all children's hospitals in Germany are asked two times yearly to notify invasive cases by a case report form and to send in blood samples. Disease severity is calculated by a score based questionnaire. Host susceptibility is examined by tests for functional asplenia, defects in complement cascade (CH50, mannose binding lectine, properdine) and a screening for single nucleotide polymorphisms in molecules of the innate immune system. The reported cases are matched with those of the National Reference Centre for Meningococci (NRCM), where epidemiologic and genetic characterisation of the meningococcal isolates is performed.

Results: Our return rate is 21% of all cases in Germany, and approximately 33% of all cases in the paediatric age group, with a matching rate of 97% for our returns with the NRCM. Severe sepsis made up 17%, 13% requiring ventilator therapy, 16% vasopressors, respectively. Overall mortality was 8.5%. Petechiae proved to be the cornerstone to raise clinical suspicion of the disease. In our immunological screening we found about one third of patients with at least a preliminary suspicion for underlying immunological disease.

Conclusions: The German Meningococcal Network shows to be a since 2008 well established tool to investigate interrelationship between bacterial and host mechanisms of disease severity. Continuation and further evaluation is encouraged as well as participation of all colleagues - including those dealing with adult patients - faced with treatment of acute invasive meningococcal disease.