Question

Case Study #2

A 59-year-old man presents with a one-day history of fever, abdominal cramps and diarrhea. His symptoms began six hours after the onset of the "runs" in two of his grandchildren and their mother all of whom had been visiting from their dairy and poultry farm in Wisconsin. The day before becoming ill all had eaten a meal consisting of Caesar salad, pasta with stir fried vegetables, bread and apples. His wife prepared her popular homemade mayonnaise.  Other than the abdominal pain and six unformed bowel movements which contained mucus, he had no complaints.

On examination the man appeared ill. Temperature was 39.3 C, pulse 100 and blood pressure 110/80 standing. He had no rash. The abdomen was tender in the periumbilical area. No pain noted otherwise. Laboratory studies presented below.

White Blood Cell Count                              9.8 X 103 /mm3 Fecal leukocytes                                  Positive Fecal occult blood                                        Negative Stool culture is growing motile, lactose non-fermenting, gram negative rod that is H2S positive.

1. What is the likely cause of this man's diarrhea?
2. Do these organisms cause diarrhea by invasion of the mucosal lining or toxin production?
3. How did the members of the family become infected?  What is the usual route of infection with this pathogen?  
4. What is the preferred therapy of enteritis due to this organism?
5. What measures could be adopted to by this family to reduce the chance of a repeat infection later?

Answer 1

The likely cause of the man's diarrhea is because of Salmonella (gram negative, red shaped, mobile and non lactose fermenting bacteria)

This organism has an tendency to invade the lining of the small and large intestine ,so called as mucosa and a toxin is released. This toxin is called as salmonella cytolethal dispensing toxins.This has the capacity to erode the intestinal layers leading to inflammation as a result the patient will experience abdominal pain ,nausea, vomiting and diarrhea.

The members of the family could have been infected through the poultry farms, ideally it is a food borne or water borne disease. Tye route of transmission is feco oral route

The main line of therapy for this patient are

• Fluid replacement to prevent dehydration due to diarrhea
• Anti diarrheal medication to stop increased bowel movements
• Antacids to balance the pH

The following measures has to be taken to reduce the chance 9f a repeat infection later are

• Not to share clothes, towels of the sick as it can harbor the disease causing bacteria
• Do not use undercooked, uncovered ,unclean foods
• Practice Hand washing