What should a technologist do if they observe >100 cells in each large square of a hemocytometer during CSF analysis?

In the context of cerebrospinal fluid (CSF) analysis using a hemocytometer, observing over 100 cells in each large square indicates a high concentration of cells that may lead to inaccurate counting if not addressed. Making a larger dilution is the appropriate action in this scenario.

By making a larger dilution, the technologist decreases the concentration of cells, thus reducing the likelihood of counting errors due to overcrowding on the hemocytometer's grid. This helps ensure that each cell can be accurately visualized and counted, providing more reliable and valid results. A too high cell density may cause overlap and hinder adequate differentiation between individual cells, ultimately affecting the overall analysis.

Regarding the other options, counting all four corner squares would not be advisable in this situation since the excessive number of cells would lead to congested counting fields. Making a smaller dilution defeats the purpose as it would exacerbate the problem of high cell concentration. Lastly, not performing any dilution at this high density of cells would likely result in erroneous counts, making it essential to dilute adequately to maintain accuracy in the results.