Detection of Proteus mirabilis urease gene in urinary calculi by polymerase chain reaction.
BACKGROUND
Urea-splitting microorganisms cannot always be detected by stone or urine culture in patients with infection stones. Detection of genetic elements within the calculi by the polymerase chain reaction (PCR) may be a useful alternative. In this study, we assessed the usefulness of the PCR method in detecting the urease gene specific to Proteus mirabilis in urinary calculi.


METHODS
Thirty-eight metabolic stones (calcium oxalate and/or calcium phosphate, uric acid, or cystine) and 49 struvite stones were examined. The PCR was applied with DNA extracted by boiling pulverized stone pieces.


RESULTS
Of the 87 stones, PCR demonstrated the presence of the P. mirabilis urease elements ureC1 and ureC2 in 17, all of which were struvite. Stone culture and urine culture had been performed in 22 and 46 struvite stone cases, respectively, and the PCR was positive in all of the 10 culture-positive calculi and also in two calculi from which P. mirabilis was not isolated.


CONCLUSIONS
PCR was reliable and convenient for detecting P. mirabilis in desiccated struvite calculi. Study to detect other species such as Ureaplasma or Corynebacterium would be useful in elucidating the role of bacterial infection in the formation of these stones.
Takeuchi
H
H
Department of Urology, Faculty of Medicine, Kyoto University, Japan.
Yamamoto
S
S
Terai
A
A
Kurazono
H
H
Takeda
Y
Y
Okada
Y
Y
Yoshida
O
O
D000328:Adult; D000368:Aged; D001426:Bacterial Proteins / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D005260:Female; D005798:Genes, Bacterial / Q000502:physiology; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011513:Proteus mirabilis / Q000201:enzymology* / Q000235:genetics*; D012680:Sensitivity and Specificity; D014510:Urease / Q000235:genetics*; D014545:Urinary Calculi / Q000201:enzymology / Q000235:genetics / Q000382:microbiology*
D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D014510:Urease