Balamuthia mandrillaris: pathogenesis, diagnosis, and treatment

ABSTRACT

Introduction: Balamuthia mandrillaris is known to cause a fatal infection of the central nervous system termed granulomatous amoebic encephalitis (GAE). Cases of GAE by B. mandrillaris are usually fatal indicating the inefficacy of currently available regimens used to treat the disease and the virulent nature of the amoebae.

Areas covered: This review discusses the current treatment options, diagnosis, and pathogenesis of Balamuthia mandrillaris. In this regard, a PubMed search using pathogenesis, treatment, and diagnosis, combined with B. mandrillaris as keywords, was performed. In addition, conference proceedings, and discussions in Free-Living-Amoebae meetings over the past 20 years were reviewed.

Expert opinion: Despite the current treatment and diagnostic options, the mortality rates due to B. mandrillaris infections remain alarmingly high. The actual number of GAE cases due to B. mandrillaris are much higher than the currently reported number. Information on the pathogenesis of the amoebae is limited, highlighting the need for further studies on the pathogenesis of B. mandrillaris. This would provide useful information to improve both diagnostic and treatment options. Similarly, new molecules that are targeted toward B. mandrillaris and can penetrate the blood-brain barrier should be established. Theranostics may be the way forward for the treatment of B. mandrillaris.

KEYWORDS:

• B. mandrillaris
• treatment
• in-vitro
• granulomatous amoebic encephalitis
• pathogenicity
• diagnosis
• free-living amoebae

Article highlights

• Pathogenicity, clinical diagnosis, and treatment options of brain infection due to B. mandrillaris.

• Exposure to soil-related activities is often linked to this devastating infection.

• Skin lesions and/or cerebrospinal fluid provides a useful tool in the rapid diagnosis of GAE due to B. mandrillaris.

• Using nanotechnology, conjugation with metal nanoparticles is shown to enhance the efficacy of available drugs.

• A complete understanding of the pathogenesis and pathophysiology of GAE due to B. mandrillaris is critical in the effective management of this devastating infection.

This box summarizes the key points contained in the article.

Declaration of interest

The authors were supported by the American University of Sharjah. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer Disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was supported by the American University of Sharjah.