Treatment of febrile geriatric patients with suspected urinary tract infections in a hospital with high rates of ESBL producing bacteria: a cohort study

Laboratory Tests, Bacterial Resistance, and Treatment Options in Adult Patients Hospitalized with a Suspected Urinary Tract Infection

Patients treated for systemic urinary tract infections commonly have nonspecific presentations, and the specificity of the results of the urinalysis and urine cultures is low. In the following narrative review, we will describe the widespread misuse of urine testing, and consider how to limit testing, the disutility of urine cultures, and the use of antibiotics in hospitalized adult patients. Automated dipstick testing is more precise and sensitive than the microscopic urinalysis which will result in false negative test results if ordered to confirm a positive dipstick test result. There is evidence that canceling urine cultures if the dipstick is negative (negative leukocyte esterase, and nitrite) is safe and helps prevent the overuse of urine cultures. Because of the side effects of introducing a urine catheter, for patients who cannot provide a urine sample, empiric antibiotic treatment should be considered as an alternative to culturing the urine if a trial of withholding antibiotic therapy is not an option. Treatment options that will decrease both narrower and wider spectrum antibiotic use include a period of watching and waiting before antibiotic therapy and empiric treatment with antibiotics that have resistance rates > 10%. Further studies are warranted to show the option that maximizes patient comfort and safety.

[Utility of the blood culture in infection of the urinary tract with fever in the elderly]

OBJECTIVE

Urinary tract infections are one of the most common community infections. The diagnosis of urinary infections in the elderly is complex because of its presentation and clinic. The aim of this article is to evaluate the usefulness of blood cultures in febrile urinary tract infection in elderly patients, risk factors, causes of discordance between urine and blood cultures, usefulness of biomarkers and mortality.

METHODS

Observational study of patients admitted over 65 years old, with urinary infections.

RESULTS

A total of 216 episodes with urinary infections and blood cultures performed. 70 (32,4%) cases with bacteremia. The most frequently detected isolates in blood cultures were: Escherichia coli 50 (71,4%) and Proteus spp. 6 (8,5%). Only septic shock was associated with a higher frequency of bacteraemia (OR=2,93, IC 95: 1,0-8,5; p=0,04). In 26 of the blood cultures a different isolation of the urine culture was detected. Overall mortality was 9.1%, with no association with the presence of bacteremia (p>0. 05).

CONCLUSIONS

One third of elderly people hospitalized by tract urinary infection had bacteremia. Their detection was not associated with overall mortality. Disagree between blood and urine cultures in febrile is frequent, especially in patients with recent antibiotic treatment or recently hospitalized.

Bacterial Resistance to Cephalosporin Treatment in Elderly Stable Patients Hospitalized With a Urinary Tract Infection

BACKGROUND

It is unclear if parenteral cephalosporin treatment is appropriate in stable elderly patients hospitalized with a urinary tract infection (UTI) in settings with a high prevalence of bacterial resistant organisms.

METHODS

We selected 934 consecutive stable patients aged ≥65 years with a UTI, 94.4% (n = 882) treated with a parenteral cephalosporin. Patients were divided into those with and without bacterial resistance to initial antibiotic therapy (BRIAT). Outcome measures were response to antibiotic therapy at 72 hours, prolonged hospitalization (>5 days) and mortality.

RESULTS

There were 316 patients (33.8%) with BRIAT. At 72 hours, 33.9% (107/316) did not respond to initial treatment. The odds of a prolonged hospitalization was 2.1 (95% confidence interval-1.6-2.9), but no patient with BRIAT died from urosepsis (0%, 95% confidence interval-0-1.2%).

CONCLUSIONS

In elderly stable patients hospitalized with a UTI, treatment with a parenteral cephalosporin might be appropriate despite a high prevalence of resistant organisms.

Prevalence, impact, and management strategies for asymptomatic bacteriuria in the acute care elderly patient: a review of the current literature

Introduction: It is unclear how to prevent the negative impact of inappropriate urine cultures in older acute care patients who have a high rate of asymptomatic bacteriuria.Areas covered: A nonsystematic literature review of the definition, impact, and management of elderly acute care patients with asymptomatic bacteriuria (ASB).Expert opinion: In the elderly, patients with ASB include those with extra-urinary tract diseases (e.g. pneumonia) and those with symptoms/signs that resolve without antibiotic therapy, but the diagnosis of ASB is unclear in febrile patients responding to antibiotics. We consider four management strategies that could decrease the negative impact of culturing the urine including unnecessary antibiotic therapy in those with ASB: (1) Prevent urine testing in patients with extra-urinary tract reasons for their acute care (2) Cancel urine cultures if the urine dipstick is negative. (3) Avoid catheterization in stable patients who cannot provide a urine specimen on demand and (4) Withhold antibiotics in stable non-febrile elderly patients who do not have new local urinary tract symptoms or decompensation on follow-up, and pursue further investigations for another etiology/diagnosis.

Sensitivity of the dipstick in detecting bacteremic urinary tract infections in elderly hospitalized patients

BACKGROUND

The sensitivity of the dipstick in elderly patients with a suspected urinary tract infection (UTI) is unclear because of the inclusion of patients with urine contamination or asymptomatic bacteriuria in previous studies.

METHODS

We selected consecutive patients aged 65 years or older hospitalized in internal medicine departments with bacteremic UTI (same organism in blood and urine cultures) minimizing misclassifications. The false positive rate was determined in consecutive patients with negative culture results. A positive dipstick was a test result with a trace leukocyte esterase and/or nitrite positivity. Bacteriuria was the growth of at least 105 colony-forming units per milliliter of urine.

RESULTS

Of 20,555 consecutive patients, 228 had a bacteremic UTI, and 4069 a negative culture result. The sensitivity of the dipstick was 96.9% (95% CI-93.7-98.6) with a false positive rate of 42.4% (95% CI, 41.0-43.8) in those with a negative culture result.

CONCLUSIONS

In elderly hospitalized patients with a bacteremic UTI, the dipstick urinalysis is highly sensitive, much higher than reported previously in studies of UTIs in the elderly. It is unclear whether the observed high sensitivity of the dipstick was due to the exclusion of patients with asymptomatic bacteriuria or to spectrum bias. Studies of the clinical utility/disutility of using a negative dipstick to rule out a urinary tract infection are warranted.

Long-term outcomes of inappropriate antibiotic therapy for upper urinary tract infections caused by extended-spectrum beta-lactamase-producing Enterobacteriaceae: a retrospective cohort study

BACKGROUND

To evaluate the short- and long-term outcomes of different antimicrobial treatment options for upper urinary tract infections (UTIs) caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae.

METHODS

We retrospectively analyzed patients with a first episode of febrile UTI and positive urine culture with ESBL-producing E. coli or K. pneumoniae during 2012-2015. We compared outcomes among patients who received: (1) definitive treatment with a carbapenem (CP), (2) a microbiologically appropriate intravenous non-carbapenem agent (NCA), (3) a non-appropriate antimicrobial (NAA), and (4) an intravenous NAA followed by an oral NCA (NAA-PO).

RESULTS

The majority of patients received empirical therapy with NAA (165/178, 93%), and definitive treatment with NCA (n=43), NAA (n=50), and NAA-PO (n=59). The NCA group had significantly higher SIRS score than the NAA-PO group (2.18 versus 1.76, P=0.018), but no differences were found between the NCA and NAA groups (2.18 and 1.92, P=0.15). Clinical cure at discharge from the index hospitalization was high (97-100%) in all 3 groups. The NCA group had longer length of stay as compared with the NAA-PO and NAA groups (8.7days versus 5.39 and 5.24days, P<0.0001) and a lower rate of early (48-72h) improvement (79% versus 96-100%, P=0.0002). Among re-admitted patients, re-admission with ESBL-related bloodstream infection was significantly higher in the NAA group as compared to the NAA-PO and NCA groups (33% versus 4% and 0%, respectively, P=0.02). Death rate within 60days was also higher in the NAA and NCA groups as compared with the NAA-PO group (P=0.048).

CONCLUSIONS

Inappropriate antimicrobial therapy for febrile non-bacteremic UTI with ESBL-producing enterobacteriaceae is associated with favorable short-term outcomes, but also with a long-term risk of relapsed bacteremic UTI. Definitive treatment with appropriate carbapenem-sparing antimicrobial agents effectively prevents late relapses.