Abstract
While determining polyamine levels in body fluids, unexpected values probably due to bacterial growth during storage are occasionally obtained. In this paper, we determined the effect of four common bacteria, namely, Escherichia coli, Streptococcus faecalis, Pseudomonas aeruginosa and Bacillus subtilis, which are often seen in urine samples, on various polyamine levels. Urines which were sterified by filtration through a 0.22?Em millipore filter, Sterifil D-G S, and then contaminated with Escherichia coli showed significantly high to tal polyamine values as compared to the corresponding sterified urines. This increase was mainly ascribed to free putrescine and cadaverine which were produced by Escherichia coli during storage. Acetylated polyamines were not increased in those samples.
In contrast, the total polyamine levels, both free and acetylated polyamine levels, were found decreased in urine contaminated with Pseudomonas aeruginosa. In case of urine samples collected from patients, however, 8 out of 10 showed increase in free polyamine levels, and the other 2 samples did not show any change. Streptococcus faecalis and Bacillus subtilis had no effect on polyamine levels in urine. To avoid such changes in polyamine levels in urine due to bacterial growth during storage, polyamine, if possible, should be determined soon after collecting urine samples. Either sodium azide or toluene, if not evaporate during storage, is useful for determination of polyamine in 24 hour urine samples, or for storage of urine at 4 for 24 hours by preventing a factitious increase or decrease in the polyamine concentration due to bacteria in urine.
