The three strongest risk factors for increasing the likelihood of UTI in multivariable analysis were mechanical ventilation (OR = 4.45, 95% CI: 1.68 - 11.7, p<0.05), blood transfusion (OR = 2.12, 95% CI: 1.0 - 4.5, p<0.05), hospital stay > 7 days (OR = 25, 95% CI: 5.49 - 85.5, p<0.001.