Sphingomonas paucimobilis, bacteria widely present in soil and water, are often ingested by healthy dogs without a problem. As the bacteria are ever present in their outdoor environment, they are not commonly pathogenic in dogs. But, in rare cases, the immuno-compromised canine in a veterinary hospital setting can succumb to a secondary infection. Of greater concern is the zoonotic aspect of the bacteria.
Sphingomonas paucimobilis is a non-fermenting, gram-negative bacterium that forms yellow or white colonies. Rather than directly infecting an otherwise healthy host organism, Sphingomonas paucimobilis is an opportunistic and nosocomial -- or hospital-acquired -- pathogen that targets underlying diseases in individuals with reduced resistance.
Sphingomonas paucimobilis bacteria require oxygen, so they are commonly found in water and soil sources. But they also have the metabolic versatility to successfully colonize on a variety of organic compounds including cleaners and herbicides. In a veterinary setting, S. paucimobilis can colonize in cleaning solutions and on respiratory equipment, kennels, exam tables and temperature probes.
What makes S. paucimobilis bacteria unique is their preference for contaminants and their zoonotic tendencies. Zoonotic diseases are those that can transfer between humans and other animal species. With veterinary equipment as a main vector for infection, this pathogen can pass from animal to human and vice versa, undetected. Your dog could carry the pathogen unharmed and transfer it to you.
A pup with a weakened immune system may suffer from infections of the blood, urine or cerebrospinal fluid, or from infection at any open wounds. An infected dog who bites a human can thus infect the person with this pathogen, requiring antibiotic treatment. Even without the presence of a dog, an immunocompromised person may unknowingly come into contact with bacteria inadvertently, allowing it to infect an open wound or be ingested.
Avenues for possible infection are similar in dogs and humans. Sphingomonas paucimobilis infection respond well to tetracyclines, trimethoprim-sulfamethoxazole, aminoglycosides, some penicillins and quinolones. And while S. paucomobilis responds to several antibiotics, over time the overarching concern with such bacteria becomes one of resistance. Antibiotics are effective, but only if they are able to wipe out an entire colony of bacteria and further contamination does not take place, especially by altered strains. Culturing veterinary surfaces on a regular basis can help monitor for bacterial growth, reduce unnecessary antibiotic usage and help prevent a resistant strain of these bacteria from taking hold.
- Oxford Journals: Nosocomial Infections Caused by Sphingomonas paucimobilis: Clinical Features and Microbiological Characteristics
- University of Tennessee Center for Environmental Biodiversity: The Genus Sphingomonas: Physiology and Ecology
- Centers for Disease Control: Diseases From Dogs
- Clinical Infectious Diseases: Sphingomonas Paucimobilis
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