dos Santos Oliveira PM, et al. - As purinergic neurotransmission dysfunction is assumed to have a role in bipolar disorder (BD), researchers examined the predictive value of higher serum uric acid (UA) levels for BD conversion in depressed inpatients. Records of major depressive disorder patients who had routine testing for UA levels between June 2007 and June 2010 were retrospectively reviewed. Two hundred fifty patients including 55 “BD-converters” and 195 “No BD-converters” were analyzed. Outcomes revealed a higher risk of a subsequent manic or hypomanic episode among depressed patients with higher levels of serum UA. “BD-converters” vs “No BD-converters” had significantly higher plasma UA levels in their index hospitalization, regardless of gender.