Naegleria fowleri (cont.)
How is a Naegleria fowleri infection diagnosed?
A spinal tap will be done to examine the spinal fluid. Infection is diagnosed by seeing the amoeba under the microscope. Traditional Gram staining is not used to detect Naegleria because the heat used in the fixation process destroys the organism. Although not specific to Naegleria, the spinal fluid often has a mild elevation in the levels of proteins and a mild decrease in glucose, along with a high white cell count, and is often bloody in the later stages of disease.
Because rapid diagnosis is critical, examination of the spinal fluid is imperative. The organism can also be cultured in the laboratory using on a plate that is coated with bacteria for the amoeba to eat. The culture takes a few days. Newer tests are becoming available that use polymerase chain reaction (PCR) technology to detect amoebic DNA in spinal fluid.