Meningococcal bacterial DNA load at presentation correlates with disease severity

AIMS: To determine bacterial loads in meningococcal disease (MCD), their relation with disease severity, and the factors which determine bacterial load. METHODS: Meningococcal DNA quantification was performed by the Taqman PCR method on admission and sequential blood samples from patients with MCD. Disease severity was assessed using the Glasgow Septicaemia Prognostic Score (GMSPS, range 0-15, severe disease > or =8). RESULTS: Median admission bacterial load was 1.6 x 10(6) DNA copies/ml of blood (range 2.2 x 10(4) to 1.6 x 10(8)). Bacterial load was significantly higher in patients with severe (8.4 x 10(6)) compared to milder disease (1.1 x 10(6), p = 0.018). This difference was greater in septicaemic patients (median 1.6 x 10(7) versus 9.2 x 10(5), p or =8) and maximum load is highest in those who die. Bacterial load is independent of the duration of clinical symptoms or the decline in DNA load.