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A 4-year-old was bitten on her hand by her pet cat. Two days later, the bite area was swollen and had some drainage. A Gram’s stain of the pus revealed small gram-negative coccobacilli. The most likely identity of this organism is:

Assuming the teacher was unwilling to change the common pencil box practice, what is the most effective way to break the chain of infection caused by this classroom behavior?

Case Study 4:   An 8-year-old female was brought to the walk-in clinic by her mother. For the last three days she has been complaining that her ear has been bothering her and last night she developed a low fever.  Her vaccinations are all up to date, her medical history is unremarkable, and she has had no previous illness; she is a healthy girl. Her mother mentions that she is very active in sports, alternating between swimming and soccer competitions every weekend. The physician collected a culture and stat gram stain of the outer ear canal. The gram stain showed many white blood cells and gram-negative bacilli.  The physician then gave the girl antibiotic drops to use twice a day for seven days without waiting for the culture results. Case Study 4 Question 1:  What infection does the little girl have?

Within 5 hours of returning home from lunch at your favorite all-you-can-eat buffet restaurant you feel very sick and are vomiting. The most likely cause is:

Which of the following organisms would be suitable as positive and negative controls, respectively, for the oxidase test?

An iInfection with this organism is associated with human bite wounds:

A non-fermentative, gram negative bacillus was isolated from the sputum of a patient with cystic fibrosis. The colonies were green on SBAP and MAC, oxidase positive, and had a characteristic grape-like odor. What is the most likely identity of this organism?

Which is NOT a characteristic of Stenotrophomonas maltophilia?

Case Study 2:  This 63-year-old alcoholic was taken to the emergency room of an outside hospital with obvious gangrene of both feet.  He was stuporous.  During that evening, he had a seizure and was treated with phenytoin and barbiturates.  By the night of transfer he was noted to have opisthotonic posturing and to have developed increasing respiratory distress and unresponsiveness.  On examination, he had a temperature of 41.7°C rectally, a blood pressure of 70/30 mmHg, a heart rate of 110 beats/min, and a respiratory rate of 40/min.  Examination was notable for marked trismus.  The neck was stiff and hyperextended.  Necrotic, blackened areas were present over both feet and several draining ulcers were noted on the heels and toes.  Neurologically the patient responded to deep pain with a grimace.  On the basis of these findings, specific therapy, in addition to supportive care, was initiated, and the patient ultimately recovered. Case Study 2.4:  How might this secondary infection have been prevented?

Which organism is the MOST COMMON cause of food-borne bacterial gastroenteritis in the US is: