[Sialic acid determinations of serum and urine specimens in calcium-containing urinary stone formers].
OBJECTIVE
The aim of the present study was to compare sialic acid concentrations of serum and urine specimens in both calcium (Ca)-containing urinary stone formers and non-stone formers. Moreover, we studied inhibitory activity of sialic acid upon the calcium oxalate (CaOx) crystal aggregation and growth.


METHODS
Sialic acid determinations were done on fresh serum and urine samples of 35 Ca-containing urinary stone formers (stone formers group) and 20 non-stone formers (patient controls group). Inhibitory activity of sialic acid upon the CaOx crystal aggregation and growth was studied by using in vitro assay method of seed crystal system.


RESULTS
Serum sialic acid concentrations were found to be similar in the two groups. Urinary sialic acid concentrations were significantly lower in the urine specimens of stone formers than in their patient controls. Sialic acid showed a dose dependent inhibitory activity upon the CaOx crystal aggregation and growth into seed crystal method.


CONCLUSIONS
It is suggested that urinary sialic acid may play some role during the phase of stone formation from the results of the present study, because sialic acid shows marked inhibitory activity upon the CaOx crystal aggregation and growth at concentrations higher than 100 mg/dl.
Konya
E
E
Department of Urology, Kinki University School of Medicine.
Umekawa
T
T
Kurita
T
T
Iguchi
M
M
Kataoka
K
K
D000368:Aged; D002129:Calcium Oxalate / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019158:N-Acetylneuraminic Acid / Q000097:blood* / Q000652:urine; D014545:Urinary Calculi / Q000737:chemistry* / Q000378:metabolism
D002129:Calcium Oxalate; D019158:N-Acetylneuraminic Acid