Background: The concentrations of glucose and lactate in cerebrospinal fluid (CSF) provide important information about energy metabolism in the CSF compartment. To improve our understanding of this information we introduced a new parameter resulting from a formula for calculating the fictitious production of adenosine triphosphate, i.e., the coefficient of energy balance (KEB).Methods: We evaluated cytology, the concentrations of glucose and lactate and the KEB in the CSF of 948 patients, who were divided into five groups. For statistical analysis we used the Kruskal-Wallis test with post-hoc analysis using the Dunn method and multinomial regression analysis. We determined the specificities and sensitivities of the cytological pictures and the KEB.Results: A KEB>28.0 corresponded to normal energy metabolism in the CSF. A KEBConclusions: The KEB represents an equation for calculating the fictitious average number of ATP molecules produced in the CSF compartment from one molecule of glucose, and we used it successfully as a new parameter for evaluating energy metabolism status in the CSF.