Cryptococcus pneumonia is caused by inhalation of spores from which organisms, and which populations are at highest risk?

Cryptococcus pneumonia is caused by inhalation of spores from which organisms, and which populations are at highest risk?

• A. Transmission by person-to-person droplets.
• B. Inhalation of Cryptococcus neoformans or C. gattii spores; commonly found in soil contaminated with bird droppings; infection particularly in weakened immune systems.
• C. Only occurs in children.
• D. Contaminated water.

Answer: (C)

Inhalation of environmental spores from Cryptococcus species is how cryptococcal pneumonia typically starts. The main organisms are Cryptococcus neoformans and Cryptococcus gattii, which are commonly found in soil contaminated with bird droppings (especially pigeons). The infection tends to occur in people with weakened immune systems—most notably those with advanced HIV/AIDS, organ transplant recipients, or individuals on immunosuppressive therapy or chronic steroids. Because the inhaled spores seed the lungs first, pulmonary disease is common, and dissemination to other sites (like the meninges) can occur in those with poor immune defenses. The other ideas—person-to-person droplet transmission, disease only in children, or contamination from water—do not fit the usual transmission or risk pattern.

Inhalation of environmental spores from Cryptococcus species is how cryptococcal pneumonia typically starts. The main organisms are Cryptococcus neoformans and Cryptococcus gattii, which are commonly found in soil contaminated with bird droppings (especially pigeons). The infection tends to occur in people with weakened immune systems—most notably those with advanced HIV/AIDS, organ transplant recipients, or individuals on immunosuppressive therapy or chronic steroids. Because the inhaled spores seed the lungs first, pulmonary disease is common, and dissemination to other sites (like the meninges) can occur in those with poor immune defenses. The other ideas—person-to-person droplet transmission, disease only in children, or contamination from water—do not fit the usual transmission or risk pattern.