Endocrine Abstracts

Urinary steroid profiling by capillary gas chromatography is useful for identification of disordered steroid metabolism and, when 24h collections are made, for determination of steroid production rates. We have noted a substantial clinical demand for analysis of random collections, most commonly from children with precocious puberty and a general belief that relating steroid levels to creatinine would offset the disadvantage of a short collection. Given the known circadian var...

For investigation of mild glucocorticoid resistance, dexamethasone may be inappropriate because, unlike cortisol, it crosses the blood-brain barrier and suitably low doses are difficult to titrate. Prednisolone has been proposed as an alternative but assay of cortisol as an endpoint is subject to cross-reaction with prednisolone in most ligand assays. Using capillary gas chromatography, we can distinguish urinary cortisol and prednisolone metabolites. We have compared this app...

Acute cortisol increase in man, whether from endogenous or exogenous sources, is associated with changes in cortisol:cortisone equilibrium. We have examined these during normal daily circadian rhythms and following treatment with hydrocortisone. Following local ethical committee approval, four adult volunteers (2 male) collected urine samples over 3 hour periods starting from midnight and over hourly periods between 0600 & 0900 to define the morning cortisol peak. They pro...