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IMMUNOLOGIC STUDY OF STRAINS OF BACILLUS PFEIFFERI ISOLATED FROM A CASE OF MENINGITIS
1Nelson Morris Memorial Institute for Medical Research of the Michael Reese Hospital, Chicago.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Five Bacillus pfeifferi strains from meningitis patients showed significant immunologic variation. Despite differences, genetic relatedness is inferred, suggesting organism instability impacting epidemiology and serum therapy for meningitis.
Area of Science:
- Microbiology
- Immunology
- Epidemiology
Background:
- Bacillus pfeifferi strains were isolated from various sites in a meningitis case, including spinal fluid, blood, nose, throat, and nasopharynx.
- Previous studies indicated significant variations among B. pfeifferi strains, complicating classification and understanding of infections.
Purpose of the Study:
- To investigate the immunologic and genetic relationships among five B. pfeifferi strains isolated from a single meningitis case.
- To assess the implications of observed strain variations on the epidemiology and potential serum therapy of B. pfeifferi infections, particularly influenzal meningitis.
Main Methods:
- Isolation of five Bacillus pfeifferi strains from clinical samples (spinal fluid, blood, nose, throat, nasopharynx).
- Application of immunologic reactions (agglutination, complement fixation, opsonin reactions) to assess strain relationships.
- Genetic relatedness inferred despite observed immunologic differences.
Main Results:
- Immunologic reactions revealed no definite relationships between the five B. pfeifferi strains.
- Significant strain variations were observed, comparable to those found between strains from different cases or individuals.
- Despite immunologic differences, the strains are believed to be genetically related, suggesting potential organism instability.
Conclusions:
- The extensive variations observed in B. pfeifferi strains may indicate a degree of biological instability.
- This instability could have implications for understanding the epidemiology of B. pfeifferi infections and the efficacy of serum therapy for influenzal meningitis.
- Observed strain variations do not support the etiological role of B. pfeifferi in epidemic influenza, especially given the limited increase in meningeal involvement during pandemics.
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