A collection of reagents and other associated materials intended to be used for the qualitative and/or quantitative measurement of the deformability of leukocytes in a clinical specimen within a short period, relative to standard laboratory testing procedures, using a rapid microfluidic cytometry method. This is a rapid test used in the laboratory or in point-of-care analyses to aid in the early diagnosis of sepsis. It is not intended to be used for self-testing.