Role of Oxalobacter formigenes in calcium oxalate stone disease: a study from North India.
OBJECTIVE
The present study was performed to detect the presence of an oxalate degrading bacteria Oxalobacter formigenes in the GI tract of calcium oxalate stone patients and normal individuals from North India. Furthermore, the possible relationship of this bacterium with number of stone episodes in this part of the world was also studied. The correlation of the presence or absence of O. formigenes with the urinary oxalate levels was evaluated.


METHODS
DNA was extracted from the stool samples of 63 calcium oxalate stone formers and 40 normal individuals. Polymerase chain reaction (PCR) was performed using genus specific primers for O. formigenes. The presence of which was confirmed by Southern blotting. Urinary oxalate levels were tested in each patient.


RESULTS
As shown by PCR and Southern blotting, O. formigenes was present in 65% of normal individuals and in 30% of calcium oxalate stone formers. In patients with three or greater than three stone episodes colonies were present only in 5.6% of patients. Oxalate excretion was less in patients colonized with O. formigenes as compared to those with no colonization.


CONCLUSIONS
In North Indian population the absence of O. formigenes can lead to a significant increase in the risk of absorptive hyperoxaluria and resultant recurrent calcium oxalate stone episodes.
Department of Urology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Raebareli Road, Lucknow-226014, Uttar Pradesh, India.
R
R
Kumar
M
M
Mukherjee
M
M
Bhandari
A
A
Kumar
H
H
Sidhu
R D
RD
Mittal
D000293:Adolescent; D000328:Adult; D000368:Aged; D015139:Blotting, Southern; D002129:Calcium Oxalate / Q000032:analysis*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D020624:Oxalobacter formigenes / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D014545:Urinary Calculi / Q000737:chemistry / Q000453:epidemiology / Q000382:microbiology*
D002129:Calcium Oxalate