Background: Cell Blood Count (CBC) are performed with automatic analysers in laboratories.It works based on three principles electrical impedance, scatter light and flowcytometry. Many factors might affect results by these machines. This study was performed to assay the effect of some confounders on the results of analysers that work based on electrical resistance.

Material and method: This analytical study (case- control) was conducted on 243 persons with hyperglycemia and hyperlipidemia and 100 healthy persosn (control group) in Fateme Zahra Hospital in North of Iran, Golestan. First, Blood glucose and triglyceride were measured with biochemical analyser and CBC was performed for each person. Finally, Statistical analysis and comparison between two groups were performed with SPSS software.

Resuts: Comparison between case and control group was shown that both hyperlipidemia and hyperglycemia cause increase in  Mean Cell Volume (MCV) and also hyperlipidemia can cause increase in Mean Cell Hemoglobin Concentration (MCHC), Hemoglobin and Hematocrit (Hct) with (P<0.05)

Conclusion: According to this study, confounding factors such as hyperglycemia and hyperlipidemia can affect the results of analysers that work based on electrical impedance and it should be considered in laboratories.