Chapter 5 - Clinical Corner

Neisseria meningitidis, commonly known as meningococcus, is a Gram-negative bacterium that not only can cause meningitis but also can enter the bloodstream and cause a deadly infection of the blood. If the bacteria do invade the bloodstream, the death rate can be very high. Luckily, if it is detected early, doctors can administer antibiotics that kill the bacteria. However, once antibiotics have been administered and the bacteria have been killed, the patient can often get much sicker before recovering.

A. Can you identify the virulence factor that might be responsible for this ‘turn for the worse’ after antibiotic killing of these Gram-negative bacteria?

B. Imagine you must explain to the patient’s concerned family what is happening inside the patient’s body after antibiotic treatment. What would you say, in simple terms?



Imagine that a new drug has been designed that targets and destroys the M protein of a deadly strain of Streptococcus. It is experimental and your very ill patient might be able to benefit from this new treatment. The doctor has presented the idea to the patient’s family but needs a signed consent form. The family is confused, however, about how this treatment will actually work. They’ve never heard of something called M protein. They turn to you to see whether you know how this might help. How would you explain this to them in simple terms that they can understand? (Be sure to explain to them what you know about M protein, what it does, and what the benefits of destroying it would be.)