Primary Amebic Meningoencephalitis (PAM), which is a disease caused by an infection with Naegleria fowleri, typically increases its prevalence during summer, but changing epidemiological and geographic conditions mean this is not always the case. Due to the increasing duration of high temperatures across the country – a result of climate change – the presence of this heat-loving, brain-eating amoeba is spreading across more states each year. Historically, most cases occur in Florida and Texas, along with other southern states, though cases are beginning to creep northward. Clinical awareness of these conditions is critical for a rapid suspected diagnosis and confirmatory testing, which can then prompt the initiation of appropriate treatment. It is important that PAM is considered among the earlier differential diagnosis.

Yes. We developed this new rapid polymerase chain reaction (PCR) test in the AdventHealth Microbiology Lab to screen for the three most common free-living amoebas at once. Along with Naegleria fowleri, it also detects:

• Balamuthia mandrilaris – Found in soil and very deadly. This amoeba is responsible for a rare and serious infection of the brain called granulomatous amebic encephalitis (GAE).
  
  
• Acanthamoeba spp. – Also found in soil, bodies of water, food, surfaces, air conditioning and heating systems and animal tissue. This amoeba causes eye infections and is commonly found infecting contact lenses. With a short turnaround time from specimen receipt, our test is offered 24/7 and is designed to be highly sensitive and identify low levels of amoebas in spinal fluid.

There are two or three other molecular-based methods across the nation, each using a different molecular approach. The Centers for Disease Control and Prevention (CDC) is the main reference center and can identify Naegleria fowleri on spinal fluid by a PCR test and this test has its own technical specifications. Our test can screen and identify the three more clinically significant free-living amoebas during the same run, where the CDC assays are individually focused. Also, our test can be performed in samples held and transported at room temperature, facilitating the logistics and expediting the transportation of the specimen.

AdventHealth had two significant cases in recent years, so our team clearly understood the critical importance of a rapid and reliable diagnostic tool, but unfortunately, there is not a commercially available molecular test for detecting free-living amoebas in cerebrospinal fluid (CSF). This led us to start this journey to innovate and improve the outcomes for future patients with suspected PAM, using our expertise and internal resources. Initially, we developed a microscope-based method, but it was time consuming and lacked the sensitivity needed to identify low levels of amoebas in spinal fluid. We took it to the next level by developing this molecular-based method to obtain the quality result we were hoping for.

Pre-pandemic, we researched and read about various molecular approaches, and a rapid PCR-based assay seemed to be the most practical, quick and sensitive method. We used the Aries multiplex PCR open platform intended for Laboratory Developed Test (LDT) for this assay and began the initial testing and fine-tuning process. During the pandemic, this project was placed on hold because AdventHealth was one of the first health systems to perform in-house COVID-19 testing and the Aries platform was rapidly converted to perform COVID-19 testing. However, our team’s learnings from early COVID PCR testing gave us valuable insights that helped us further develop this amoeba PCR test. As COVID-19 cases decreased in January 2022, we resumed this project and were able to fully launch this test for patient use on July 24.

PAM is one of many infectious syndromes where there is a gap in diagnostic methods or understanding the clinical need for an appropriate treatment. Although my team is not in a research department and we do not a have dedicated research budget, we always focus on translational research and look for opportunities to improve or design a diagnostic method, protocol or algorithm with a positive patient impact. My advice to fellow physicians is to have a broad, comprehensive understanding of the problem, research the current methods or guidelines available and then challenge ourselves and ask the question, “how do we make it better?”