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Endotoxin liberation and invasivity of Neisseria meningitidis
Abstract:
The relationship between endotoxin liberation and invasiveness was studied in 50 strains of Neisseria meningitidis isolated from blood or cerebrospinal fluid (CSF) of 16 patients with invasive disease, from nasopharynx of 9 patients with upper respiratory tract symptoms, and from nasopharynx and rectum (1, serogroup W-135) in 25 persons examined for venereal disease. Meningococci varied in their ability to liberate endotoxin. Free endotoxin was partly a function of growth and seemed to be associated with certain properties of the individual strain. Strains isolated for patients with invasive disease liberated significantly more endotoxin than strains isolated from the venereal group (p less than 0.002). All 16 invasive strains were sulfonamide resistant, against 5/9 strains from patients with upper respiratory disease symptoms and only 4/25 strains from the venereal group. The difference between the invasive group and the venereal group was significant (p less than 0.002). Serogroup A, B, C meningococci liberated significantly more endotoxin than non-A, B, C strains (p = 0.01, and serogroup A, B, C strains isolated from nasopharynx tended to have a higher endotoxin release than non-A, B, C strains isolated from the same place (not significant). Serogroup B meningococci were most frequently isolated both from patients with invasive disease and from the nasopharynx of the persons examined for venereal disease. Serogroup B meningococci had significantly more free endotoxin when isolated from blood or CSF than when isolated from nasopharynx of presumably healthy persons (p = 0.002).
Insights
Invasive Neisseria meningitidis strains release more endotoxin and are more resistant to sulfonamides than those from non-invasive sources. Serogroup B strains showed higher endotoxin levels in invasive disease compared to asymptomatic carriage.
Area of Science:
- Microbiology
- Infectious Diseases
- Bacteriology
Background:
- Neisseria meningitidis is a significant human pathogen.
- Endotoxin liberation and antibiotic resistance are key factors in meningococcal disease.
Purpose of the Study:
- To investigate the relationship between endotoxin release and invasiveness in Neisseria meningitidis.
- To assess sulfonamide resistance patterns in different clinical isolates.
Main Methods:
- Analysis of 50 Neisseria meningitidis strains from various sources (blood, CSF, nasopharynx, rectum).
- Quantification of endotoxin liberation.
- Determination of sulfonamide resistance.
Main Results:
- Invasive strains released significantly more endotoxin than strains from the venereal disease group (p < 0.002).
- All invasive strains were sulfonamide-resistant, contrasting with non-invasive groups (p < 0.002).
- Serogroup B strains showed higher endotoxin levels in invasive disease compared to carriage (p = 0.002).
Conclusions:
- Endotoxin liberation and sulfonamide resistance are associated with Neisseria meningitidis invasiveness.
- Serogroup B strains may possess specific characteristics contributing to invasive disease potential.