Dialysis of saliva improves accuracy of saliva lithium determinations.
BACKGROUND
Saliva lithium (Li) determinations have been explored as a potential alternative to plasma levels. Unfortunately, this method has been shown to be unreliable. Saliva has two major components: the aqueous and the mucopolysaccharide portions.


METHODS
Since Li is likely to distribute only in the aqueous fraction, we dialyzed the saliva through a 3000 Da filter to isolate the aqueous component and determine the Li level in it.


RESULTS
Lithium levels in the dialyzed saliva agreed more closely with plasma levels (Spearman's rho = 0.901, p < 0.001) than did whole saliva (Spearman's rho = 0.775, p = 0.012).


CONCLUSIONS
Dialysis of saliva may contribute to more accurate saliva Li levels.
Mood Disorders Research Program, Department of Psychiatry, School of Public Health and Information Sciences, University of Louisville, Louisville, KY 40292, USA. rselma01@athena.louisville.edu
Rif S
RS
El-Mallakh
Mark
M
Linder
Roland
R
Valdes
Stephen
S
Looney
D000328:Adult; D001714:Bipolar Disorder / Q000097:blood / Q000188:drug therapy* / Q000378:metabolism; D003956:Dialysis; D005260:Female; D006801:Humans; D008094:Lithium / Q000032:analysis*; D008297:Male; D012463:Saliva / Q000737:chemistry / Q000378:metabolism*
D008094:Lithium