Review Question - QID 109838

An 11-year-old boy is brought to his pediatrician by his mother after he has complained of worsening left thumb pain for the last two weeks. The mother reports that the patient was previously healthy. Approximately 2 weeks ago, the family cat bit the patient’s thumb. The area around the bite wound then became red, hot, and slightly swollen and never healed. Earlier this week, the patient also started developing fevers that were recorded at home to be as high as 103.6°F. On exam, the patient's temperature is 102.2°F (39.0°C), blood pressure is 112/72 mmHg, pulse is 92/min, and respirations are 14/min. The patient’s left thumb is tender to touch over the proximal phalanx and the interphalangeal joint, but there is no obvious erythema or swelling. A radiograph performed in clinic is concerning for osteomyelitis at the proximal phalanx. Which of the following is the most likely cause of this patient’s condition?