Low impact of urine cultures as a diagnostic tool in patients with neutropenic fever

Role of urine culture in paediatric patients with cancer with fever and neutropenia: a prospective observational study

OBJECTIVE

To evaluate the need for routine urine studies in children with febrile neutropenia with cancer.

DESIGN

A prospective, observational study was conducted in two hospitals between November 2019 and October 2021.

PATIENTS

We recruited 205 patients in total.

MAIN OUTCOME MEASURES

The primary outcome was presence of positive urine culture (UC). Urinary tract infection (UTI) was defined as urinary signs/symptoms and positive UC with or without pyuria. A descriptive analysis of data is provided.We conducted a prospective study of paediatric patients with cancer with urinary continence. Data were analysed using descriptive statistics. The diagnostic performance of urinalysis was calculated using positive UC as the gold standard.

RESULTS

Positive UC was found in 7 of the 205 patients (3.4%; 95% CI 1.4% to 6.9%), 2 presenting urinary symptoms. UTI prevalence was 1.0% (95% CI 0.1% to 3.5%). A 23.8% prevalence of positive UC was found in patients with urinary symptoms and/or history of urinary tract disease (95% CI 8.2% to 47.2%) as compared with 1.1% of those without symptoms or history (95% CI 0.1% to 3.9%) (p<0.001). The sensitivity, specificity, negative predictive value, and area under the curve for urinalysis were 16.7% (95% CI 3.0% to 56.4%), 98.4% (95% CI 95.3% to 99.4%), 97.3% (95% CI 93.9% to 98.9%), and 0.65 (95% CI 0.51 to 0.79), respectively.

CONCLUSIONS

UTI is an infrequent cause of infection in these patients. Urinalysis is indicated only in children with febrile neutropenia with urinary signs/symptoms and in asymptomatic patients with a history of urinary tract disease or unknown history. When urine is collected, UC should be requested regardless of the result of the urinalysis.

Utility of Urine Cultures During Febrile Neutropenia Workup in Hematopoietic Stem Cell Transplantation Recipients Without Urinary Symptoms

The utility of obtaining screening urine cultures for febrile neutropenia (FN) during hematopoietic stem cell transplant (HCT) is unknown. In 667 adult HCT patients with FN, only 40 (6%) were found with bacteriuria. Antibiotics were modified in 3 patients (0.4%) based on urine cultures and none developed urinary-associated infectious complications.

Outcome of febrile neutropenic patients treated for bacteriuria in hematology

INTRODUCTION

Positive urine sample is a frequent finding in post-chemotherapy febrile neutropenia (FN) and can lead to prolonged antibiotic therapy. The aim of this study was to assess the outcome of bacteriuria episodes in FN patients receiving targeted antibiotic therapy.

MATERIALS AND METHODS

A multi-centric retrospective study was conducted over a four-year period (2014-2019) on systematic urinalysis. All consecutive first bacteriuria episodes (≤ 2 bacteria with at least ≥ 10³ CFU/mL) during FN in hospitalized adult patients for hematological malignancies were included. Relapse and recurrence were defined by fever or urinary tract symptoms (UTS) with the same bacterial subspecies in urine occurring ≤ 7 days and ≤ 30 days, respectively, after antibiotic discontinuation. Mortality rate was determined at 30 days. Targeted antibiotic therapy ≤ 10 days for women and ≤ 14 for men was considered as short course.

RESULTS

Among 97 patients, 105 bacteriuria episodes on systematic urinalysis were analyzed; 67.6% occurred in women, 41.9% in AML patients, 17.1% were bacteremic, 14.2% presented with UTS, and 61.9% were treated with short-course antibiotic treatment. One death was reported. In men, no relapse/recurrence was noted, even in the short-course antibiotic group. In women, 2.8% of episodes treated with short-course antibiotic led to relapse or recurrence.

CONCLUSIONS

Relapse, recurrence, and mortality were uncommon events in FN patients experiencing bacteriuria episode, whatever the antibiotic duration. To distinguish asymptomatic bacteriuria from infection remained challenging in women. In men, systematic urinalysis at onset of FN could be useful.

Role of urine studies in asymptomatic febrile neutropenic patients presenting to the emergency department

BACKGROUND

The role of urine studies in the detection of urinary tract infection (UTI) in febrile neutropenic patients with urinary symptoms (having a urinary catheter or having a positive urine analysis) is inarguable. However, the evidence is scarce regarding the indication for urine studies in asymptomatic (i.e., without urinary symptoms) patients with febrile neutropenia (FN) presenting to the emergency department (ED). The aim of this study is to evaluate the need for obtaining urine studies in asymptomatic febrile neutropenic patients.

METHODS

This was a retrospective cohort study conducted on adult cancer patients who presented to the ED with FN and had no urinary symptoms. We included all ED presentations of eligible patients between January 2013 and September 2018. Student's t-test and Wilcoxon rank-sum test were used for continuous data, while Chi-square and Fisher's exact tests were used for categorical data. Participants were divided into two groups based on their urine culture (UC) results: negative and positive UCs. Two cut-offs were used for positive UC results: ≥10⁵ cfu/mL and ≥10⁴ cfu/mL.

RESULTS

We included 284 patients in our study. The age of our patient population was 48.5±18.5 years. More than two-thirds (68.7%) of patients had severe neutropenia, while only 3.9% and 9.9% of the patients had positive UCs at ≥10⁵ cfu/mL and ≥10⁴ cfu/mL, respectively. UCs were expectedly positive in most patients with urinalysis (UA) abnormalities. However, 27.3% and 32.1% of patients with positive UCs at ≥10⁵ cfu/mL and ≥10⁴ cfu/mL respectively had a normal UA.

CONCLUSIONS

In our study, the incidence of UTI in adult febrile neutropenic cancer patients who present to the ED without urinary symptoms is low. Consequently, routine urine testing may not be warranted in this population, as it adds unnecessary financial burdens on the patients and delays timely management.

Urine cultures at the onset of febrile neutropenia rarely impact antibiotic management in asymptomatic adult cancer patients

PURPOSE

There is a paucity of data regarding the utility of routine urine cultures in adults with febrile neutropenia (FN) without urinary symptoms receiving protocolised antibiotics. This is reflected by inconsistent recommendations in international and regional FN guidelines. We addressed this issue by retrospectively reviewing the impact of routine urine cultures on antibiotic management in haematology cancer inpatients at a tertiary hospital.

METHODS

All haematology inpatients over a 5-year period (2011-2015) were retrospectively reviewed for episodes of FN (neutrophil count < 0.5 × 10⁹/L and fever > 37.5 °C). For each episode, demographic data, urinary tract symptoms and signs (absence of which was termed 'asymptomatic'), urinalysis and urine culture results, antibiotic therapy and duration, and patient outcomes were collected. A urine culture was considered positive if > 10⁵ colony forming units (CFU)/L were detected. Empiric antibiotic therapy for FN consisted of intravenous piperacillin/tazobactam in stable patients, with the addition of vancomycin and a single dose of gentamicin if systemically compromised.

RESULTS

Four hundred and thirty-three episodes of FN were identified in 317 patients. Urine cultures were performed in 362 (84%) episodes. Cultures were positive in 9 of 48 (19%) symptomatic episodes versus 8 of 314 (2.5%) asymptomatic episodes (RR = 7.4, p < 0.0001). A change in antibiotic management due a positive urine culture occurred in only 5 episodes (1.4%): 3 of 48 (6.3%) symptomatic and 2 of 314 (0.6%) asymptomatic episodes respectively (RR = 9.8, p = 0.01).

CONCLUSION

Routine urine cultures in FN patients without urinary symptoms who are already receiving protocolised broad spectrum antibiotics rarely impact subsequent antibiotic management.