An Improved Specimen Handling Procedure for Pathogen Detection of the Cerebrospinal Fluid by Microscope

In order to increase the detection rate of pathogenic microorganisms in CSF, an improved specimen handling procedure (ISHP) was created.

This study enrolled encephalitis and control groups, both groups were handled with traditional specimen handling procedure (TSHP) and ISHP. Glutaraldehyde was added to the ISHP. Observed items included: total protein, glucose, chloride, adenosine deaminase, lactate dehydrogenase, sediment, cell and pathogen, Pandy's test.

Sediment test of CSF: There was 1 specimen in 10 control specimens tested by TSHP in which Pandy's test was positive; there were 2 specimens tested by ISHP which could see sediment by eye. There was no statistical difference between those two methods (p = 1.000, Table 1). Ten specimens in 23 of the encephalitis group processed by TSHP were positive with Pandy's test; 23 specimens processed by ISHP could all see sediments by eye (Figure 1). There was a statistical difference between the two methods (p = 0.000, Table 1). Pathogen test of CSF: no pathogen was found in the control group processed by TSHP and ISHP. No pathogen was found in the encephalitis group specimens processed by TSHP. Pathogen tests were positive in 7 encephalitis specimens processed by ISHP (p = 0.009, Table 1), which were confirmed as Rickettsia spp. by Gimenze stain (Figure 1B), IFA (Figure 2).

The results revealed that ISHP contributes to the separation of cells, pathogens (such as Rickettsia), and proteins.