Urinary plasma protein patterns in acute prostatitis.

Abstract

We evaluated the diagnostic utility of urinary alpha1-microglobulin, alpha2-macroglobulin and albumin in the diagnosis of acute prostatitis. We studied 133 men (43 +/- 17 years) with, and a reference population (n=36, 41 +/- 16 years) without, urinary tract infection. Prostatectomy samples were used to study the potential interference between prostatic proteins and protein analysis. Urinary alpha2-macroglobulin/albumin ratio was significantly lower in prostatitis compared to the reference population, cystitis or acute pyelonephritis (p < 0.0001). Low alpha2-macroglobulin concentrations in prostatitis are due to inhibition (p = 0.0001) of the immune reaction between alpha2-macroglobulin in presence of polyclonal rabbit antibodies (used for immunonephelometry) by soluble prostatic proteins (+/- 60 kDa) which appear in urine in acute prostatitis. The urinary alpha1-microglobulin/creatinine ratio diagnoses acute pyelonephritis (sensitivity 100% and specificity 87%) and the urinary alpha2-macroglobulin/albumin ratio diagnoses acute prostatitis (sensitivity 100% and specificity of 90%). Stepwise multinomial logistic regression analysis reveals that urinary alpha1-microglobulin, alpha2-macroglobulin, albumin and creatinine provide optimal differentiation between acute pyelonephritis and acute prostatitis (pseudo R2=0.83; Loglikelihood -30.55, p < 0.000001). In conclusion, the combination of hematuria and absence of urinary alpha-2-macroglobulin is diagnostic for acute prostatitis. Even without hematuria, alpha2-macroglobulin remains lower compared to patients without prostatitis.

• Authors: Karel Everaert, Joris Delanghe, Marc Vanderkelen, Kristof Cornelis, Stefaan De Wachter, Annick Viaene, Eddy De Ruyck, Bart Clarysse, Willem Oosterlinck
• Journal: Clinical chemistry and laboratory medicine (Clin Chem Lab Med) Vol. 41 Issue 1 Pg. 79-84 (Jan 2003) ISSN: 1434-6621 [Print] Germany
• PMID: 12636054 (Publication Type: Journal Article)

Chemical References

• Albumins
• Alpha-Globulins
• Biomarkers
• Protease Inhibitors
• alpha-1-microglobulin
• alpha-Macroglobulins

Topics

• Acute Disease
• Adult
• Albumins (metabolism)
• Alpha-Globulins (urine)
• Biomarkers (urine)
• Cystitis (diagnosis, urine)
• Humans
• Male
• Middle Aged
• Prostatitis (diagnosis, urine)
• Protease Inhibitors (urine)
• Pyelonephritis (diagnosis, urine)
• Sensitivity and Specificity
• alpha-Macroglobulins (urine)