Related Experiment Videos
A pink-pigmented, oxidative, nonmotile bacterium as a cause of opportunistic infections
J A Korvick1, J D Rihs, G L Gilardi
1Veterans Administration Medical Center, Infectious Disease Section, Pittsburgh, PA 15240.
Abstract:
We describe two cases of bacteremia due to a pink-pigmented, oxidative, nonmotile, gram-negative, rod-shaped organism. One case occurred in a febrile neutropenic patient and another in a chronically debilitated patient with pancreatic abscess. The first patient was cured with gentamicin and ticarcillin, but the second patient died while receiving cefamandole therapy. The organisms described here are similar to Methylobacterium mesophilicum (Pseudomonas mesophilica) and the "unnamed taxon" organisms. A major difference from M mesophilicum is the lack of methanol utilization. Further distinctions between our isolates and M mesophilicum are the lack of flagella in our organisms, growth at 42 degrees C, growth on MacConkey's agar, lack of acetamide assimilation, and citrate utilization. The lack of flagella is the principle difference between our isolates and those in the unnamed taxon. Both of the isolates were resistant to the cephalosporins, but susceptible to the aminoglycosides, ticarcillin-clavulanic acid, sulfamethoxazole and trimethoprim, and imipenem. With the growing population of immunocompromised and chronically ill patients, these organisms may emerge as important pathogens.
Insights
Two cases of bacteremia caused by a novel pink-pigmented, gram-negative rod highlight potential emerging pathogens. These bacteria, distinct from known species, pose a threat to immunocompromised patients.
Area of Science:
- Medical Microbiology
- Infectious Diseases
Background:
- Bacteremia in immunocompromised patients presents a significant clinical challenge.
- Identifying novel bacterial pathogens is crucial for effective treatment strategies.
Observation:
- Two cases of bacteremia were reported, caused by a pink-pigmented, oxidative, nonmotile, gram-negative, rod-shaped organism.
- One patient was neutropenic and febrile; the other was debilitated with a pancreatic abscess.
Findings:
- The organism differed from Methylobacterium mesophilicum by lacking methanol utilization, flagella, and utilizing citrate.
- Isolates were resistant to cephalosporins but susceptible to aminoglycosides, ticarcillin-clavulanic acid, and imipenem.
Implications:
- These distinct organisms may represent emerging pathogens in vulnerable patient populations.
- Understanding their characteristics is vital for diagnosing and treating infections in immunocompromised individuals.