Case 14 answers

Gina presents with gastrointestinal complaints to the clinic at 8:00 am. Last night Gina and Gerry went out to celebrate their wedding anniversary. They went to their favorite restaurant complete with salad bar. They left the restaurant to go to a movie at about 7:00 pm. However, about 1 hour into the post-dinner movie Gina started complaining that she felt sick to her stomach. So sick she vomited twice in the movie theater restroom and once on the way home. She vomited all night long and was just starting to be less nauseous in the waiting room to the clinic (wouldn't you know you always feel better when you are at the doctor's office). Gerry took Gina's vitals and all her vital signs were normal. In fact, he mentioned that he thought she probably got food poisoning. Gina thought it had to be much worse than just food poisoning. The vomitus was shooting out of her mouth into the toilet. She mentioned eating potato salad from the salad bar, a medium well done top sirloin steak and steamed vegetables. Gina's vital signs were normal. She mentioned her upper right abdomen was sore. Her upper right quadrant was tender to palpation. No other areas of the abdomen were tender to palpation.

A. Which of the following is a strong indication that Gina had an intoxication rather than an infection due to food poisoning?

Projectile vomiting- can happen in an infection or an intoxication. Usually, think of staphylococcal food poisoning with this symptom. However, other causes of food poisoning could cause this.
Nausea- can happen in an infection or an intoxication
Diarrhea- can happen in an infection or an intoxication
One hour incubation time* a short incubation time is a strong indication that a toxin is involved. An infection would take from 24-72 hrs before symptoms begin.

B. Which of the following is the most likely cause of Gina's current condition?

Bacillus cereus- if vomiting usually associated with fried rice.
Clostridium perfringens- usually most common symptom is diarrhea
Staphylococcus aureus*- vomiting is the most common symptom. Potato salad is a highly processed food that could be contaminated by humans colonized by S. aureus.
Adenovirus- longer incubation time would be expected.
Norovirus- longer incubation time would be expected.

Meanwhile, Gerry mentioned feeling nauseous and needed to go to the restroom while you examined Gina. Gerry came back to your examining room feeling worse. He mentioned having diarrhea. Vital signs were all normal. Gerry ate a T-bone steak medium well, some green beans and mashed potatoes and gravy (no salad bar) at the restaurant last night. The T-bone was huge so he asked for a doggy bag and took home the leftover steak, mashed potatoes, and gravy. He left the doggy bag on the kitchen countertop while caring for Gina. Between her vomiting episodes he managed to put the mashed potatoes and gravy in a pot and warm it to eat later in the evening. It wasn't until after 4 hrs of warming the food that Gerry could get back to the mashed potatoes and gravy (around 1 am). He gulped most of them down, then put the rest in the refrigerator, and got back in the restroom just in time to help Gina and to keep Geraldine from going into the bathroom. He offered to get the remaining mashed potatoes and gravy. You mentioned it might help and that he didn't look so good. Gerry gave the keys to one of the nurses in your office and they got the food and brought it to the local health department for testing. Testing revealed large numbers of aerobic gram positive rod shaped organisms were in the food.

Geraldine, their daughter, did not go with the couple to the restaurant. She was healthy with no signs of vomiting or diarrhea.

B. Which of the following is the most likely cause of Gerry's current condition?

Bacillus cereus*- the cause of type II food poisoning with diarrhea being the most common symptom.
Clostridium perfringens- this organism is NOT aerobic. It is an anaerobic gram positive rod.
Staphylococcus aureus- gram positive coccus
Adenovirus- longer incubation time would be expected.
Norovirus- longer incubation time would be expected.

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