Acanthamoeba spp.

Definition

Acanthamoeba spp. are free-living amoebae that can cause serious infections in the human nervous system, particularly a rare but severe condition known as granulomatous amoebic encephalitis (GAE). These opportunistic parasites are ubiquitous in the environment and can pose a threat to immunocompromised individuals.

5 Must Know Facts For Your Next Test

1. Acanthamoeba spp. are free-living amoebae found in a variety of environmental sources, including soil, water, and air.
2. These amoebae can enter the human body through the nasal passages, skin, or eyes, and migrate to the central nervous system.
3. Granulomatous amoebic encephalitis (GAE) is a rare but often fatal infection of the brain and spinal cord caused by Acanthamoeba spp.
4. Individuals with weakened immune systems, such as those with HIV/AIDS, organ transplants, or cancer treatments, are at a higher risk of developing GAE.
5. Amoebic keratitis is a serious eye infection caused by Acanthamoeba spp., often affecting contact lens wearers who do not properly clean and disinfect their lenses.

Review Questions

• Describe the key characteristics of Acanthamoeba spp. that contribute to their ability to cause infections in the nervous system.
  • Acanthamoeba spp. are opportunistic pathogens that are ubiquitous in the environment. They can enter the human body through various routes, such as the nasal passages, skin, or eyes, and migrate to the central nervous system. These free-living amoebae are particularly dangerous for individuals with weakened immune systems, as they can cause a rare but severe infection called granulomatous amoebic encephalitis (GAE), which is often fatal if not promptly diagnosed and treated.
• Explain the role of host immune status in the development of Acanthamoeba-related infections, such as granulomatous amoebic encephalitis.
  • Individuals with compromised immune systems, such as those with HIV/AIDS, organ transplants, or undergoing cancer treatments, are at a significantly higher risk of developing granulomatous amoebic encephalitis (GAE) caused by Acanthamoeba spp. These opportunistic parasites take advantage of the host's weakened defenses to invade the central nervous system and cause a devastating infection. The ability of Acanthamoeba to evade the host's immune response and establish a foothold in the brain and spinal cord is a key factor in the development of this rare but often fatal condition.
• Analyze the importance of proper contact lens hygiene in preventing Acanthamoeba-related eye infections, such as amoebic keratitis.
  • Amoebic keratitis, a serious eye infection caused by Acanthamoeba spp., is particularly prevalent among contact lens wearers who do not properly clean and disinfect their lenses. The presence of Acanthamoeba in the environment, combined with the ability of these amoebae to adhere to and proliferate on contact lens surfaces, creates a significant risk for individuals who wear contact lenses. Proper lens hygiene, including thorough cleaning, disinfection, and replacement of lenses according to the manufacturer's instructions, is crucial in preventing this debilitating eye infection and preserving vision. Failure to maintain good contact lens practices can lead to Acanthamoeba gaining access to the cornea, where they can cause severe inflammation, scarring, and potentially blindness.

Related terms

Granulomatous Amoebic Encephalitis (GAE): A rare but severe infection of the brain and central nervous system caused by Acanthamoeba spp., often affecting immunocompromised individuals.

Amoebic Keratitis: An eye infection caused by Acanthamoeba spp. that can lead to vision impairment or blindness, typically affecting contact lens wearers.

Opportunistic Pathogen: A microorganism that can cause disease, especially in individuals with weakened immune systems or underlying health conditions.