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Published on: April 7, 2015
PASTEURELLA SEPTICA INFECTIONS IN HUMANS
Abstract:
Five instances of infection by Pasteurella septica, an organism which closely resembles H. influenzae on methods of presumptive bacteriology, are reported from an acute treatment general hospital practice over a period of three months. This infection decidedly outnumbers those caused by other Pasteurella species in North America. The organism is apt to be identified as H. influenzae, Friedlander's bacillus or Mima polymorpha. Unlike these, it shows extreme sensitivity to penicillin, sometimes combined with resistance to antibiotics that inhibit or kill these other organisms.While in the past Pasteurella septica infection was considered to be characterized by persistent local infection following domestic animal scratches or bites, it is clear that it is more often found in cases of respiratory tract infection and peripheral septic disease. In three of the five cases reported, exposure to animals was the source of infection.Because mixed infection with confusingly similar organisms may occur, lack of awareness of extreme penicillin sensitivity of Pasteurella septica may account for persistent failure of antibiotic therapy.
Insights
Pasteurella septica infections are increasingly common, often mistaken for other bacteria. This organism shows unique extreme sensitivity to penicillin, crucial for effective treatment.
Area of Science:
- Microbiology
- Infectious Diseases
Background:
- Pasteurella septica infections are often misidentified in clinical settings.
- This organism can be mistaken for Haemophilus influenzae, Friedlander's bacillus, or Mima polymorpha.
Purpose of the Study:
- To report five cases of Pasteurella septica infection.
- To highlight the diagnostic challenges and unique antibiotic sensitivities of Pasteurella septica.
Main Methods:
- Case reporting from an acute treatment general hospital practice.
- Presumptive bacteriological identification and antibiotic sensitivity testing.
Main Results:
- Five cases of Pasteurella septica infection were identified over three months.
- Pasteurella septica demonstrated extreme sensitivity to penicillin, unlike commonly mistaken organisms.
- Infections were associated with respiratory and septic diseases, with animal exposure in three cases.
Conclusions:
- Pasteurella septica infections are more prevalent than previously thought in North America.
- Misidentification can lead to treatment failure due to lack of awareness of its unique penicillin sensitivity.
- Prompt and accurate identification is critical for effective antibiotic therapy.
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