Question

The surgical ward at a public hospital was having an outbreak of diarrheal illness. The patients with the illness had all had surgery and were taking antibiotics as preventative measure to prevent infection. Symptoms of the disease cramping, numerous bloody stools and inflammation of the colon. A Gram positive, endospore forming bacillus was isolated from 25 patients. Three of these patients died.

a. What was the probable “etiological” agent (pathogen)?

b. What is the most likely source of his infection, and how would you verify this?

c. Determine if the illness was due to an intoxication or an infection and give the information you based your answer on.

d. What was the probable treatment protocol for this illness? (how were they treated

e. Explain how this outbreak could have been prevented.

Answer 1

Answer a) Clostridium difficile infection.

Clues to the diagnosis:

1. History of surgery.
2. History of antibiotics given
   1. mostly these patients were prescribed broad- spectrum antibiotics
   2. The human gut contains bacteria that help in the process of digestion
   3. these bacteria are good bacteria or commensals.
   4. They also prevent the growth of pathogenic bacteria in the gut
   5. Indiscriminate antibiotics usage causes death of these good bacteria.
   6. As a result, pathogenic bacteria like clostridium difficile grow in the gut.
   7. Antibiotics known to that have the capacity of leading growth of clostridium difficile are
      1. Fluoroquinolones
      2. Cephalosporins
      3. Clindamycin
3. Symptoms
   1. Diarrhoea
   2. Blood in stool
   3. Cramping sensation
   4. Inflammation of colon - colitis
   5. Once the C. difficile proliferates it produces toxins (A and B )
   6. These toxins bind to specific receptors and causes diarrhoea.
4. Gram positive bacillus with spore. C.difficile produces spores. These spore are considered to be the vehicles of infection transmission of C. Difficile

Answer b - most likely source is the hospital itself.

This can be confirmed by

• Collecting all the relevant clinical and microbiological data.
• The clinical information should also include the antibiotic given to the patient and duration.
• Obtain swabs from the wards patients were admitted to and also collect the swabs from the hands of health care workers taking care of these patients.
• Send these swaps for culture of c.difficile

Answer c : the illness was due to:

• Poor hand hygiene practices followed by the healthcare workers. This lead to transmission of spores of C.difficile between patients.
• Usage of broad spectrum antibiotics of prevention of infection ( this altered the normal gut flora)

Answer d :

These patients were probably given the following antibiotics:

1. Clindamycin
2. Cephalosporins - cefotaxime, ceftriaxone
3. Fluoroquinolones
4. Carbepenem

Antibiotics used to treat C.difficile are

• Vancomycin
• Metronidazole

Answer e:

1. Avoid unnecessary usage of antibiotics.
2. Practice hand hygiene procedures by health care workers.
3. Patients who were diagnosed with the infection should have been isolated.
4. The antimicrobial which lead to the development of C.difficle infection should have been discontinued.
5. Early administration of fluid therapy (to reduce dehydration and renal failure) and antibiotics to treat the infection.
6. Disinfection of all the items that have come in contact with the patients ( linen, beds, carts, thermometers etc) with chlorine bleaach.
7. Inform the health authorities about the outbreak of infection.