Differentiation of Proteus mirabilis by bacteriophage typing and the Dienes reaction

Area of Science:

• Microbiology
• Bacteriology
• Infectious Diseases

Background:

• Proteus mirabilis is an opportunistic pathogen.
• Accurate strain differentiation is crucial for infection control and epidemiology.
• Existing typing methods for Proteus mirabilis have limitations.

Purpose of the Study:

• To establish a provisional bacteriophage typing schema for Proteus mirabilis.
• To evaluate the efficacy of this schema in a clinical setting.
• To compare bacteriophage typing with the Dienes reaction.

Main Methods:

• Isolation and selection of 73 bacteriophages active against Proteus species.
• Computer analysis to select the best 23 bacteriophages for a provisional typing system.
• Retrospective study of 200 patient isolates of Proteus mirabilis using bacteriophage typing and the Dienes reaction over 19 months.

Main Results:

• The provisional schema differentiated 200 Proteus mirabilis strains into 113 distinct lysis patterns, with 94% typability.
• Bacteriophage typing demonstrated high sensitivity in differentiating strains.
• Evidence of only three instances of cross-infection or -colonization was found.
• The Dienes reaction was less reliable, with difficult-to-read or inconsistent results.

Conclusions:

• Bacteriophage typing is a highly sensitive and valuable tool for differentiating Proteus mirabilis strains.
• The developed schema is effective for studying Proteus mirabilis infections in hospitals.
• Further work towards a standardized bacteriophage typing schema for Proteus mirabilis is warranted.