These characteristics include high renin levels, hypertension which is non modulating, or non dipping, or salt sensitive, as well as insulin sensitivity, left ventricular hypertrophy, microalbuminuria and an elevated level of erythrocyte sodium/ lithium countertransport. Looking at these characteristics, there is an apparent paradox, in that salt sensitivity is often assumed to be a low renin state. However the intriguing observations of a recent study, by Ferri and colleagues in Rome and Boston, have resolved some of this confusion.