Cortisol, LC/MS, Saliva, 4 Samples - Salivary cortisol level, particularly late-night salivary cortisol (LNSC) level, is useful in screening for endogenous Cushing syndrome. Two or more positive results of LNSC tests may be used to confirm Cushing syndrome. LNSC measurement may also be used to monitor for recurrence of Cushing disease.