Infections related to healthcare in patients hospitalized in a Urology service: resistance patterns and adequacy of empirical antibiotic treatment as a prognostic factor

OBJECTIVES

To evaluate the suitability of empirical antibiotic therapy in HAIs and the antibiotic resistance patterns of the responsible microorganisms, as well as the incidence of mortality and risk factors involved.

METHOD

A prospective observational study was carried out on patients of both sexes older than 16years, admitted by any urological process during a period of 4years. The incidence and characteristics of HAIs, as well as the causative organism and its resistance, the initial empirical antibiotic therapy and its modification, if required, and mortality rates are analysed.

RESULTS

Out of 6,546 patients, 6.3% suffered HAIs, 70.5% corresponding to urinary tract infection and 22.1% to infection of the surgical wound. E.coli, Enterococcus spp., Klebsiella spp. y P.aeruginosa were the most frequently implicated (25.1%, 17.5%, 13.5% and 12.3%, respectively). E.coli and Klebsiella spp. were producers of extended-spectrum beta-lactamases (ESBL) in 24.7% and 47.8%, respectively. 4.3% of Klebsiella and 33.3% of Pseudomonas were carbapenems-resistant. The overall resistance to quinolones was approximately 50%. The most commonly used antibiotics for empirical therapy were cephalosporins of 3rd and 4th generation (33.6%) and carbapenems (28.2%). An overall rate of adequacy of empirical antibiotic therapy of 82.9% was obtained. The mortality rate in patients with HAIs was 2.2%, compared with 0.3% in patients without infection. In a multivariate analysis, the variables associated with the highest mortality risk were the isolation of ESBL-producing enterobacteria and the inadequate empirical antibiotic treatment.

CONCLUSIONS

The selection of empirical antibiotic therapy was quite accurate. An increase in HAIs by multiresistant microorganisms, such as ESBL Enterobacteria or multiresistant P.aeruginosa is being observed. The mortality risk increases with inadequate initial empirical antibiotic therapy or when the responsible microorganism is an ESBL enterobacteria.

Surgical wound infection in urology. Analysis of risk factors and associated microorganisms

OBJECTIVES

Open surgery continues to have a fundamental role in urology, and one of its main complications is surgical wound infection. Our objective was to analyse surgical wound infection in patients who underwent surgery in our Department of Urology and to assess the risk factors, microorganisms and resistances by type of surgery.

MATERIAL AND METHODS

This was a prospective observational study that included 940 patients: 370 abdominal/open lumbar surgeries and 570 genitoperineal surgeries. We analysed age, sex, comorbidities, stay and type of surgery, as well as the causal microorganisms and antibiotic resistances.

RESULTS

For genitoperineal surgery, we found 15 cases (2.6%) of surgical wound infection associated with previous urinary catheterisation. Most of the isolated microorganisms corresponded to enterobacteriaceae, highlighting the resistance to beta-lactam. In abdominal/lumbar surgery, we found 41 cases (11.1%) of surgical wound infection. The incidence rate was 3.3% in prostate surgery; 9.8% in renal surgery; and 45.0% in cystectomy. Heart disease was associated with a higher incidence rate of surgical wound infection. The most common microorganisms were Enterococcus spp. (27.1%), E.coli (22.9%) and Staphylococcus aureus (14.6%). Enterococcus and beta-lactamase-producing E.coli are resistant to ampicillin in 37.5% and 41.7% of cases, respectively.

CONCLUSIONS

We found a low incidence rate of surgical wound infection in genitoperineal surgery, compared with renal surgery and cystectomy. The presence of heart disease and carrying a previous urinary catheter are factors associated with surgical wound infection. Enterococcus and E.coli are the most common pathogens, with high rates of resistance.

Community-associated urinary infections requiring hospitalization: risk factors, microbiological characteristics and patterns of antibiotic resistance

OBJECTIVE

Although patients with urinary tract infections (UTIs) are usually managed as outpatients, a percentage of them requires hospitalization. To review risk factors and microbiological characteristics of community-associated UTIs (CAUTIs) requiring hospitalization has been our objective.

MATERIAL AND METHODS

A prospective observational study was carried out from November 2011 to December 2013. Incidence, microbiological characteristics and antibiotic resistance patterns in patients with CAUTIs that required hospitalization were analyzed. Risk factors (including diabetes mellitus, urolithiasis, urinary catheterization) and resistance rates of each pathogen were also analyzed.

RESULTS

Four hundred and fifty seven patients were hospitalized in our department with CAUTI. The mean age was 56.2±19.85 years. Of them, 52.1% patients were women, 19.7% had urinary indwelling catheter and 11.4% have had a previous UTI. The most frequently isolated pathogens were Escherichia coli (60.6%), followed by Klebsiella (9.2%), Enterococcus (8.4%) and Pseudomonas (7.2%). Enterobacteriaceae other than E.coli were more prevalent in male and older patients. On the other side the most frequently isolated pathogen in patients with a previous UTI and a urinary catheter was Entercoccus. The resistance rates E. coli against ampicillin/amoxicillin + β lactamase inhibitor was 23.5%, against third-generation cephalosporins 16.6%, against fluoroquinolones 31.3% and 16.7% against aminoglycosides. 11.4% E. coli strains were producers of extended-spectrum Beta-lactamases (ESBL). Finally, the resistance rates of Enterococcus and Pseudomonas against quinolones were of 50.0% and 61.5%, respectively.

CONCLUSIONS

CAUTIs that require hospitalization are most frequent in older age, male gender, and presence of urinary catheter, with urolithiasis and with previous episodes of UTI. These factors are also related to isolation of pathogens other than E. coli and higher resistance rates.