Pruritus in cholestasis: no direct causative role for bile acid retention

Discrepancies have existed regarding the correlation between raised bile acid levels in cholestasis and the presence of pruritus. Nevertheless, the prevalent view is that bile acids have a direct etiologic role. To resolve the issue, we quantified separately all naturally-occurring bile acid species detectable in serum and skin, and on the skin surface of 13 patients with pruritus associated with cholestasis, 10 patients with cholestasis who did not have pruritus, three patients with uremia and generalized pruritus and in 10 controls. We were unable to find any correlations between the presence of pruritus and bile acid levels from the various sources. We did find great overlap in these same values with data from the group with cholestasis but without pruritus. As expected, the symptomatic (uremic) and asymptomatic control groups showed comparable levels. The results of the present study together with those of a similar recent study provide strong evidence against the hypothesis of a direct causative role for retained bile acids in pruritus associated with cholestasis.