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Effect of
Microorganism on Encrustation of Polyurethane Catheter
By
V.Nandakumar
Department of Biotechnology, IIT, Madras, Chennai |
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A polyurethane stent is a narrow and hollow plastic tube that
runs inside the ureter between the kidney and urinary bladder.
These stents find wide application in treatment of patients with
urological disorder where there is any obstruction to flow of
the urine.
Majority of patients (about 50%) with such stents are at a risk
of urinary tract infection. Encrustation upon implanted ureteric
stent and the ensuing complications lead to morbidity. |
The
present study is aimed at understanding the kinetics of in
vitro encrustation of Calcium oxalate the predominant salt,
in the presence of various other salts (sodium hydrogen
phosphate, magnesium sulphate hepta hydrate, ammonium chloride
and mixture of ammonium chloride- magnesium sulphate hepta
hydrate) and E.coli, a uropathogens. Calcium
oxalate is formed by the combination calcium chloride and di-sodium
oxalate. In the absence of E. Coli sodium ions favours Ca
adsorption whereas magnesium ions greatly depress it. Presence
of ammonia favours Ca adhesion by increasing the alkalinity of
the solution. The stent surface becomes more hydrophilic upon
salt deposition. In the presence of E.Coli, Mg ions
enhance the encrustation of Calcium oxalate, whereas other salts
decrease its deposition. This necessitates newer strategies to
design stents that are more inert and resist encrustation and
biofilm formation. |
