A 4-year old girl presents at the emergency room with bloody diarrhea, fever and vomiting. The child's mother reports that the child has had these symptoms for about 24 hours and she has not passed any urine for about 12 hours. The child is enrolled in a day care center and the group had recently made a field trip to a fast food place to learn about different jobs. The children had a lunch of ground beef fries and cola after meeting with different workers. This field trip was 4 days earlier on Friday. The child had a temperature of 39C and showed physical signs of dehydration. Blood samples drawn showed evidence of greatly reduced kidney function and lysed red blood cells.

1. What is your diagnosis here? What is organism is responsible?

2. What pathogenic feature of this organism caused the severity of this problem?

3. What were the critical features to your diagnosis?

Answer:

1.The child is suffering with bloody diarrhea, fever and vomiting. These symptoms mostly observed during illness caused by gastrointestinal pathogens such as Salmonella, Shigells, Compylobacter and E. coli etc. These organisms cause chronic diarrhea with pesence of blood in stool and this symptom is fatal and requires emergency treatment. The symptoms are related to conditions such as hemorrhagic colitis or hemolytic uremic syndrome.
Other possibilities include Chron's disease and gastroenteritis. These conditions are possibly caused by Escherichia coli O157:H7.

2. The pathogenesis of E. coli O157:H7 is observed in 2 stages with early and late symptoms. The early symptoms may begin after 3 to 5 days after consumption of contaminated foods. The symptoms include nausea,diarrhea resulting the stools containing blood, vomiting,anuria or stopped elimination of urine, severe impairement of kidney function and mild fever about 37.7 to 38.3⁰C.

The untreated conditions of hemorrhagic colitis may lead to hemolytic uremic syndrome with increased severity of symptoms. The patient may require hospitalization and if proper treatment is not given the infection may lead to death.

3. The condition is diagnosed by dietary assessment: consumption of ground beef. This is the source of infection. The symptoms such as diarrea with blood in stools, nausea and vomiting, reduced urination and kidney function and presence of lysed red blood cells in urine sample. These symptoms enable the diagnosis of condition is an infection caused by E. coli O157:H7.