A veterinary doctor had fever for 15 days. His blood culture in special laboratory media was positive for Gram-negative sho bacilli which were oxidase positive. Which one of the following is the likely organism grown in culture?
**Core Concept**
The question is testing the identification of a Gram-negative, oxidase-positive bacterium based on its morphology and biochemical characteristics. The organism in question is likely a member of the Enterobacteriaceae family, which is a group of Gram-negative bacteria that are commonly found in the environment and in the gastrointestinal tracts of animals.
**Why the Correct Answer is Right**
The organism described is likely *Pseudomonas aeruginosa*, which is a Gram-negative, rod-shaped bacterium that is oxidase-positive. This organism is known to grow in special laboratory media and can cause a variety of infections in animals, including fever. *Pseudomonas aeruginosa* is a common inhabitant of the environment and can be found in water, soil, and on the skin and mucous membranes of animals. It is also known to be resistant to many antibiotics, which can make it challenging to treat infections caused by this organism.
**Why Each Wrong Option is Incorrect**
*Option A:* This option is not relevant to the description of the organism provided in the question.
*Option B:* This option is not a Gram-negative bacterium, and therefore does not match the description provided in the question.
*Option C:* This option is a Gram-positive bacterium, and therefore does not match the description provided in the question.
**Clinical Pearl / High-Yield Fact**
It's worth noting that *Pseudomonas aeruginosa* is a common cause of opportunistic infections in animals, particularly those with compromised immune systems. This organism can cause a range of infections, including pneumonia, urinary tract infections, and skin infections.
**Correct Answer:** C.