Final answer:
Among the options provided, Pseudomonas aeruginosa is an opportunistic pathogen. It is specifically associated with serious bacterial pneumonia cases in patients with cystic fibrosis or hospitalized patients on ventilators. It can cause chronic lung damage and adapts to the lungs by producing alginate, leading to infection and inflammation.
Step-by-step explanation:
An opportunistic pathogen is an organism that causes disease in individuals with a weakened immune system. Among the options provided, Pseudomonas aeruginosa is a well-known opportunistic pathogen, especially in patients with cystic fibrosis (CF) or those hospitalized and assisted with artificial ventilators. In the context of pneumonia, three major pathogens responsible for the most prevalent types of bacterial pneumonia are Streptococcus pneumoniae, Haemophilus influenzae, and Mycoplasma pneumoniae. Notably, Mycoplasma pneumoniae is known to cause 'walking pneumonia,' a milder form of the disease that mostly affects young people. On the other hand, Coccidioidomycosis is referred to as Valley fever, while cryptococcosis results in meningitis caused by an encapsulated yeast.
Pseudomonas aeruginosa is a significant cause of pneumonia in specific contexts. It affects patients with CF due to a genetic defect that leads to excess dried mucus in the lungs, diminishing the effectiveness of the mucociliary escalator, and causing chronic lung damage, which is a leading cause of mortality in CF patients. In hospitals, it may be associated with ventilator-associated pneumonia caused by contaminated equipment. This bacterium is known for its antibiotic resistance and its ability to produce a protective viscous exopolysaccharide called alginate in the lungs.