Question

Case 2

A 30-year-old dairy farmer was in good health until the day prior to admission, when he felt chilled and feverish. He developed nausea, vomiting, diarrhea, and lower abdominal discomfort and presented to the emergency room, where he was noted to be lethargic. His vital signs included, temperature of 40°C. His physical examination was remarkable for lower abdominal tenderness to palpation bilaterally. A rectal examination revealed occult blood in the stool the patient was lethargic but had no focal neurological deficits. Of note, his 3-year-old child had been discharged from the hospital 2 days previously with a similar history.

The patient underwent a lumbar puncture because of his altered mental status and fever. Laboratory studies of cerebrospinal fluid (CSF) were within normal limits, and a bacterial culture of CSF was negative.  

A stool examination for fecal leukocytes was positive, and stool culture was diagnostic. Biochemical examination of the organism revealed it to be a lactose nonfermenter on MacConkey agar, H₂S negative, urea negative, and nonmotile at both 25 and 37°C.

1.  What was the most likely source(s) of infection?

1. Contaminated food
2. Contaminated water
3. Pasteurized dairy products
4. Unpasteurized products

2. On the basis of the biochemical reactions, which organism do you think this is?

1. Salmonella sp.
2. Shigella sp.
3. Escherichia coli
4. Campylobacter jejuni

3. Did the person have meningitis?

1. The patient did have meningitis, since he had “no focal neurological deficits”
2. The patient had full nerve, spinal cord, and brain function. “No focal neurological deficits”, therefore he did not have meningitis.

Answer 1

1. Option D is correct as contaminated and unpasteurized milk products are main source of contamination.

2. Option B is correct as this is the case of the Shigella sp. on the bsis of the biochemical observation like  lactose nonfermenter on MacConkey agar, H₂S negative, urea negative, and nonmotile nature

3.  Option B is correct No as the patient had full nerve, spinal cord, and brain function. “No focal neurological deficits”, therefore he did not have meningitis.