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Aim: To investigate if free PSA (fPSA) and total PSA (tPSA) values obtained from simultaneously collected urine, fresh and dried on filter paper, reflect the serum free and total PSA. Materials and Methods: The sera and 20 cc first voided urine from 33 consecutive men aged between 40 and 84 (mean 61 ± 12), were collected in the morning and delivered to the laboratory. Three different aliquots of 100 microgram urine were taken with automatic pipette and dropped on 3 certain areas of a filter paper and allowed to dry for each patient. On each paper, borders of dried urine were marked. PSA values were obtained from the sera and fresh urine samples and recorded. Later on particular days dried urine samples were dissolved and eventually PSA values were derived and recorded again. The results were compared to each other. Correlations were evaluated by using an SPSS statistics program. Results: Serum PSA values correlated weakly (r < 0.24) with fresh and dried urine PSA values. While PSA in fresh and dried urine samples showed strong correlation (0.5 < r < 0.74), a very strong correlation (r > 0.75) among PSA values of dried urine samples of 1-day, 7-.and 28-days, were seen. Conclusions: We conclude that PSA values obtained from fresh and dried urine could not reflect serum PSA values. But, because dried urine on a filter paper can be stable for years, it could be used for forensic purposes. [ABSTRACT FROM AUTHOR]

Abstract: Background: Mucopolysaccharidoses are complex lysosomal storage disorders caused by any of eleven different enzyme deficiencies resulting in the accumulation of substrates, mainly glycosaminoglycans (GAGs), in various tissues and biological fluids. Method: We developed and validated a urine filter paper methodology for the analysis of GAGs using liquid chromatography–tandem mass spectrometry (LC–MS/MS) for mucopolysaccharidoses type I, type II and type VI patients. We focused on 2 objectives: first, its applicability to high-risk screening, and secondly, to facilitate the collection and shipping of samples to reference centers as part of diagnostic investigation, as well as from treated patients needing to be monitored for assessment of the efficacy of treatment. GAGs in urine dried onto filter paper were extracted and subjected to methanolysis to obtain the repeating disaccharides of the molecules. We devised a multiple reaction monitoring method in positive electrospray ionization mode. Results: The use of deuterated internal standards for dermatan sulfate (DS) and heparan sulfate (HS) reduced a troubling matrix effect. The resulting CVs were <14%. Linearity assessment showed Pearson correlation coefficients of 0.999 and 0.997, for DS and HS, respectively. The stability on filter paper was good for DS and HS for up to 6weeks at various temperatures. Conclusion: We devised a robust and efficient LC–MS/MS methodology for GAGS quantification in urine dried on filter paper and subjected to environmental conditions likely to be encountered during collection, storage and shipping of specimens from referring physicians to medical centers. [Copyright &y& Elsevier]