Question

A patient is in the hospital with bacterial meningitis. The doctor needs to determine whether the patient has an infection with Neisseria meningitis or Haemophilus influenzae.

1. What is the problem (scenario) that you're asked to solve?

2. What is your hypothesis for the solution to the problem? What organism do you think caused the problem?

3. What are the experiments that are required to answer your hypothesis? (The stains, biochemical, and media for each organism and the expected results)

4. What is your conclusion to the problem? Based on the expected results, what organism caused the problem?

Answer 1

1. Scenaio of the problem: The first step in the process of scientific method is to make an observation of the problem. The problem (scenario) here that we would like to solve is that we have a patient who is in the hospital with bacterial meningitis and we need to know whether the patient has an infection with either the microorganism Neisseria meningitidis or Heamophilus influenzae.

According to my knowledge, Neisseria meningitidis usually appears as benign in the respiratory tract. This microorganism can cause meningitis, which causes inflammation of the coverings of the brain and spinal cord. Haemophilus influenzae also cause pneumonia and meningitis, usually in younger children.

Since they both can be known to cause bacterial meningitis, just knowing this information is not enough. Using the steps of the scientific method, we need to eliminate one of these options so that we can best begin to properly treat the patient's problem.

2. Hypothesis: This is the second step in the process of scientific method. My hypothesis is that the organism Neisseria meningitidis caused the problem that resulted in the patient having bacterial meningitis. Based on the facts of what I do know about both of these organisms, I had constructed my hypothesis.

Haemophilus influenzae spreads when it enters the nasopharynx and spreads to the blood to infect the meninges covering the brain and spinal cord. Children are often most affected by this. Since, Neisseria meningitidis is far more common, it would be more likely that this would be the cause of this particular patient's bacterial meningitis.

3. In order to test my hypothesis, I will need to continue to follow the steps of the scientific method, and conduct an experiment. The third step of the scientific method is to conduct an experimental design and experimentation. Here, we are using two or more groups of subjects(both Neisseria meningitidis and Haemophilus influenzae).
Experiment: To perform a gram stain. According to our textbook, Neisseria meningitidis, and all bacteria of the genus Neisseria, are aerobic, gram-negative cocci. Performing a gram-stain on a culture using the patient's bacterial meningitis would allow us to see if this resulted. If the sample culture from the patient does not yield these results, we would know that it could not be Neisseria meningitidis.

Another experiment to perform, since you know that Neisseria meningitidis affects the brain and spinal cord coverings, it would be appropriate to perform an analysis of the CSF could give us an indication of a presence of this microorganism. According to the lab manual, this type can be diagnosed from observing the organism that appears from culturing the spinal fluid.
4. Conclusion: The fourth step and the last step when practicing the scientific method is the generation of the conclusion. Based on the expected results of these experiments, I would expect the hypothesis to be correct in that Neisseria meningitidis caused the problem that resulted in the patient having bacterial meningitis. Haemophilus influenzae is a facultatively anaerobic, gram-negative, encapsulated, pleomorphic rod while Neisseria meningititis is an aerobic, gram-negative, encapsulated diplococcus. Based off of these experiments, I would likely find Neisseria meningitidis and could then eliminate the other option of the cause being Haemophilus influenzae.

After the conclusion is confirmed we will look into the means of treatment for the patient knowing that Neisseria meningitidis was the cause of their bacterial meningitis.