Background

There is no clear consensus on whether asymptomatic bacteriuria (ABU) should be treated in kidney transplant recipients (KTRs). We sought to identify patient or episode related characteristics associated with subsequent symptomatic urinary tract infection (UTI) and with antibiotic prescribing in KTRs with ABU.

Methods

We retrospectively recorded all episodes of ABU, cystitis and pyelonephritis in KTRs transplanted at our centre between January 1^st 2008 and June 1^st 2013. Bacteruria was defined as ≥10⁴ colony-forming units (CFU)/ml as 23% of symptomatic UTIs occurred with colony counts ≥10⁴-10⁵ CFU/ml. Through logistic regression models using generalized estimating equations to account for within patient correlations, we assessed i) factors associated with occurrence of a symptomatic UTI within 3 months of an episode of ABU; ii) factors associated with antibiotic treatment of ABU.

Results

Among 318 study participants, there were 622 episodes of ABU in 156 patients. Symptomatic UTI within 3 months occurred following 87 (14%) of ABU episodes. Factors associated with an increased likelihood of a symptomatic UTI following ABU were younger age (OR: 1.38 per 10-year decrease in age; 95% CI: 1.12-1.70), previous symptomatic UTI (OR: 5.24; 95% CI: 2.18-12.59), the presence of leukocyturia or haematuria (OR: 3.38; 95% CI: 1.86-6.17), isolation of a ciprofloxacin resistant or extended-spectrum beta-lactamase (ESBL) producing strain (OR: 2.21; 95% CI: 1.03-4.75), and isolation of gram negative bacteria (GNB) (OR: 2.44; 95 % CI: 1.12-5.31). Antibiotics were prescribed in 24% of ABU episodes. The presence of leukocyturia or haematuria (odds ratio (OR): 2.02, 95% confidence interval (CI): 1.27-3.22), urinary nitrites (OR: 2.54, 95% CI: 1.08-5.99), GNB (OR: 2.08, 95% CI: 1.11-3.85),and bacterial count >10⁵ CFU/ml (OR: 5.55 versus 10⁴-10⁵ CFU /ml, 95% CI: 3.44-8.33) were associated with an increased likelihood of receiving antibiotic treatment for ABU. We could not demonstrate an association between antibiotic treatment and protection from symptomatic UTI (OR: 0.64; 95% CI: 0.27-1.51).

Conclusion

Younger age, leucocyturia or haematuria, gram negative and quinolone-resistant or ESBL producing strains, and a history of previous cystitis or pyelonephritis are predictors of progression of ABU to symptomatic UTI that can help transplant physicians in guiding the management of KTRs with ABU and in the design of future therapeutic trials.

CITATION INFORMATION: Medani S, Dorais M, Tavares-Brum A, Mawad H, Duclos A, Lemieux C, Barama A, Cardinal H. Risk Factors for Clinical Urinary Tract Infections in Kidney Transplant Recipients with Asymptomatic Bacteriuria. Am J Transplant. 2016;16 (suppl 3).

« Back to 2016 American Transplant Congress