Neuroinvasive Free-Living Amoebae Pathogenesis, Neuroinflammation and Therapeutic Challenges

Area of Science:

• Neurology
• Infectious Diseases
• Parasitology

Background:

• Neuroinvasive free-living amoebae (FLA), including *Naegleria fowleri* and *Acanthamoeba* spp., cause severe CNS infections with high mortality rates.
• Primary amoebic meningoencephalitis (PAM) and granulomatous amoebic encephalitis (GAE) are rare but devastating, with over 90% mortality.
• PAM is rapid and typically affects healthy individuals after freshwater exposure, while GAE is indolent and common in immunocompromised hosts.

Purpose of the Study:

• To review current evidence on CNS invasion, neuroinflammation, and neuropathology in FLA infections.
• To critically analyze diagnostic challenges and therapeutic strategies for neuroinvasive FLA.
• To identify translational priorities for improving patient outcomes.

Main Methods:

• This narrative review synthesizes existing literature on neuroinvasive FLA infections.
• Evidence on CNS invasion, host responses, diagnostics, and therapeutics was critically evaluated.
• Key translational research needs were identified.

Main Results:

• FLA infections involve CNS invasion, amoeba-mediated tissue damage, blood-brain barrier disruption, and neuroinflammation.
• Diagnosis is difficult due to nonspecific symptoms and variable disease progression.
• Therapeutic options are limited by poor drug penetration, low efficacy, toxicity, and lack of standardized protocols.

Conclusions:

• Effective management of neuroinvasive FLA infections requires overcoming diagnostic and therapeutic hurdles.
• Priorities include earlier diagnosis, standardized treatment protocols, and enhanced CNS drug delivery.
• Further research is crucial for developing better treatments and improving survival rates.