While playing in the park, an 8-year-old girl is bitten in the leg by a neighbor’s cat. She presents the next day with fever and bone pain localized to her right calf. X-ray reveals a lytic lesion of the right tibia. Results of the bone culture are pending. You expect the infecting organism to be ?

**Core Concept**
The girl's presentation of fever, bone pain, and a lytic lesion on X-ray following a cat bite is suggestive of osteomyelitis, a bone infection. The type of infecting organism can be predicted based on the animal source of the bite.

**Why the Correct Answer is Right**
Cat bites, particularly those from cats that are infected with Bartonella henselae, are commonly associated with osteomyelitis. Bartonella henselae is a gram-negative bacterium that can cause cat-scratch disease (CSD), which often presents with lymphadenopathy and systemic symptoms. However, in immunocompromised individuals or following a cat bite, it can lead to osteomyelitis. The organism enters the body through the bite wound and spreads to the bone through the bloodstream.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because Pasteurella multocida is more commonly associated with dog bites, not cat bites.
* **Option B:** This option is incorrect because Staphylococcus aureus is a common cause of skin and soft tissue infections, but it is not typically associated with cat bites.
* **Option D:** This option is incorrect because Eikenella corrodens is more commonly associated with human bites, not animal bites.

**Clinical Pearl / High-Yield Fact**
When evaluating a patient with a suspected osteomyelitis following an animal bite, consider the source of the bite (e.g., cat, dog, human) and the patient's immunocompromised status, as this can influence the type of infecting organism.

**Correct Answer:** C. Bartonella henselae.

✓ Correct Answer: D. Pasteurella multocida