World Journal of Emergency Medicine, 2021, 12(2): 99-104 doi: 10.5847/wjem.j.1920-8642.2021.02.003

Original Article

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

Hady Zgheib1, Aline El Zakhem2, Cynthia Wakil1, Mohamad Ali Cheaito1, Rola Cheaito1, Antoine Finianos2, Ralphe Bou Chebl1, Rima Kaddoura1, Nader Al Souky1, Imad El Majzoub,1

1 Department of Emergency Medicine, American University of Beirut Medical Center, Beirut 11-0236, Lebanon

2 Department of Internal Medicine, American University of Beirut Medical Center, Beirut 11-0236, Lebanon

Corresponding authors: Imad El Majzoub, Email:im26@aub.edu.lb

Received: 2020-02-12   Revised: 2020-10-20   Online: 2021-06-15

Abstract

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: ≥10 5 cfu/mL and ≥10 4 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 ≥10 5 cfu/mL and ≥10 4 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 ≥10 5 cfu/mL and ≥10 4 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.

Keywords: Adult; Cancer; Emergency department; Febrile neutropenia; Urine testing

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Cite this article

Hady Zgheib, Aline El Zakhem, Cynthia Wakil, Mohamad Ali Cheaito, Rola Cheaito, Antoine Finianos, Ralphe Bou Chebl, Rima Kaddoura, Nader Al Souky, Imad El Majzoub. Role of urine studies in asymptomatic febrile neutropenic patients presenting to the emergency department. World Journal of Emergency Medicine, 2021, 12(2): 99-104 doi:10.5847/wjem.j.1920-8642.2021.02.003

INTRODUCTION

Febrile neutropenia (FN) is a life-threatening condition and an oncologic emergency with overall mortality ranging from 5.0% to 9.5% in solid tumor patients and up to 11.0% to 14.0% in liquid tumor patients.[1,2,3,4] The infection, which is mostly bacterial, is the leading cause of death in febrile neutropenic patients.[5] In fact, the infection-related mortality is as high as 2.3% and 5.0% in solid and liquid tumor patients, respectively.[4]

Urinary tract infection (UTI) is identified in 5% to 30% of adult oncology patients with FN.[6,7,8] As opposed to gastrointestinal or respiratory infections, the clinical presentation of UTI can be subtle, including only fever, in the absence of any symptoms such as polyuria, dysuria, and/or urgency.[9] In light of low clinical suspicion, urine tests might not be obtained from patients within the emergency department (ED), and therefore UTI might be overlooked. In addition, the isolation rate of urinary pathogens in cancer patients is very low, partly due to the widespread use of prophylactic antimicrobial therapy.[10,11,12] Accordingly, a previous study supported the inclusion of urine studies, namely urinalysis (UA) and urine culture (UC), in the diagnostic workup of oncology patients presenting to the ED with FN,[9] while another study questioned their utility and cost-effectiveness.[13]

According to the 2010 clinical practice guidelines of the Infectious Diseases Society of America (IDSA) on FN in adult and pediatric patients, UC is indicated only if signs or symptoms of UTI are present (a urinary catheter is in place or UA results are abnormal).[3,14,15] Nonetheless, it is important to note that this recommendation is of level III evidence, given the absence of randomized controlled studies.[16,17] Additionally, the accuracy of UA findings in detecting UTI was reported to be limited in febrile neutropenic patients,[3] as their UA may display only a little or no pyuria at all given the reduction in neutrophil granulocytes.[18] Yet, specialists from Japan, the United States of America, and some European countries recommend urine testing in the diagnostic evaluation of any febrile neutropenic patients before administrating antibiotics.[19] Relevant prospective studies are particularly rare, of small sample size, or done on pediatric populations.[9,20] This topic remains a controversy in our clinical practice.

The study aims to assess the usefulness of urine studies in detecting UTI in adult cancer patients presenting to the ED with FN but having no urinary signs or symptoms.

METHODS

Study design and setting

This was a retrospective cohort study conducted on adult cancer patients who presented to the ED of the American University of Beirut Medical Center (AUBMC), between January 2013 and September 2018, with FN but without any urinary signs or symptoms. AUBMC is an over 350-bed tertiary care center and a major referral center in Lebanon and the region, receiving more than 55,000 ED visits annually.

Study population

We included all adult patients (>18 years) who presented to the ED of AUBMC with FN but without any urinary signs or symptoms and had their urine tested as part of ED diagnostic workup prior to admission. Only the first presentation for each patient was included. We excluded patients who were not admitted, received antibiotics (other than prophylactic antibiotics) within two weeks of presentation, or were clinically/ hemodynamically unstable.

Statistical analysis

Descriptive and binariate statistics were conducted on the two groups (positive and negative UCs) with continuous variables presented as mean±standard deviation (SD) or medians and interquartile range (IQR) and categorical variables expressed as frequencies and percentages. 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. All tests were interpreted at alpha of 0.05.

The analysis was performed to determine the value of urine studies in diagnosing UTI in asymptomatic adult cancer patients with FN, with UC being considered as the golden diagnostic tool. Two cut-offs were used for UC positive results: ≥105 cfu/mL and ≥104 cfu/mL. The threshold of ≥105 cfu/mL is widely accepted and agreed upon.[14] The other cut-off we used in our study (i.e., ≥104 cfu/mL) was in accordance with evidence from studies that suggested the use of a lower threshold in a vulnerable population such as ours.[21] Although the threshold of ≥104 cfu/mL is not acknowledged by all practicing physicians, a recent study has considered it in special clinical scenarios (fever, pyuria, bacteremia, etc.);[21] thus, we adopted it in an attempt to evaluate its value. The analysis was conducted using STATA MP Version 13.p (StataCorp LP, USA).

RESULTS

Characteristics of patients

A total of 924 patients were screened, and 284 patients were included in this study (Table 1). The mean age of our population was 48.5±18.5 years. Slightly less than half of the study populations were females (48.9%) with underlying malignancies almost equally distributed between hematological and solid malignancies (49.5% and 47.0%, respectively). Only 3.5% of patients had received stem cell transplants. More than two-thirds (68.7%) of the study population had profound neutropenia. Overall, the mean Charlson Comorbidity Index (CCI) was 3.7±2.1, and the median length of stay (LOS) was 4 days.

Only 11 patients (3.9%) had a positive UC at the cut-off ≥105 cfu/mL, whereas 28 patients (9.9%) had a positive UC at the cut-off ≥104 cfu/mL. Overall, patients with a positive UC were significantly older and were more likely to be females compared with patients with a negative UC. At the cut-off ≥105 cfu/mL, patients with positive UCs were more likely to have solid tumors and profound neutropenia compared with patients with a negative UC. There was no significant difference in the CCI or LOS between both groups. At the cut-off ≥104 cfu/mL, patients with positive UCs were more likely to have solid tumors, severe neutropenia, and a higher CCI compared with patients with a negative UC. They were almost equally likely to have profound neutropenia, and there was no significant difference in the LOS between the two groups. The most common organisms were Escherichia coli (E. coli), followed by Klebsiella, Enterococcus, Lactobacillus, Proteus, and Staphylococcus aureus.

Table 1   Baseline characteristics of patients with positive and negative urine cultures at cut-offs ≥105 cfu/mL and ≥104 cfu/mL

VariablesAll
(n=284)
Cut-off ≥105 cfu/mLCut-off ≥104 cfu/mL
Positive UCs
(n=11)
Negative UCs
(n=273)
P-valuePositive UCs
(n=28)
Negative UCs
(n=256)
P-value
Age (years), mean±SD48.5±18.563.2±19.547.9±18.50.00757.5±19.547.5±18.20.007
Female, n (%)139 (48.9)9 (81.8)130 (47.6)0.03220 (71.4)119 (46.5)0.012
Tumor type, n (%)
Solid
Liquid
BMT
133 (47.0)
140 (49.5)
10 (3.5)
6 (54.6)
5 (45.5)
0 (0)
127 (46.7)
135 (49.6)
10 (3.7)
0.84316 (57.1)
12 (42.9)
0 (0)
117 (45.9)
128 (50.2)
10 (3.9)
0.358
ANC (cells/mm3), median (IQR)0 (0, 206.5)0 (0, 189)0 (0, 208)0.6040 (0, 241)0 (0, 202.5)0.933
Neutropenia, n (%)
Moderate
Severe
Profound
23 (8.1)
66 (23.2)
195 (68.7)
1 (9.1)
2 (18.2)
8 (72.7)
22 (8.1)
64 (23.4)
187 (68.5)
1.0001 (3.6)
8 (28.6)
19 (67.9)
22 (8.6)
58 (22.7)
176 (68.8)
0.557
CCI, mean±SD3.7±2.13.7±1.93.7±2.20.9314.3±2.23.6±2.10.110
LOS (days), median (IQR)4 (3, 7)3 (2, 8)4 (3, 7)0.3994 (3, 7)4 (3, 7)0.914

SD: standard deviation; IQR: interquartile range; ANC: absolute neutrophil count; neutropenia divided into moderate (500 cells/mm3<ANC<1000 cells/mm3), severe (100 cells/mm3<ANC<500 cells/mm3), and profound (<100 cells/mm3); CCI: Charlson Comorbidity Index, predicting 10-year survival in patients with multiple comorbidities; LOS: length of stay (in days), reported as median (interquartile range).

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UA results

Patients with a positive UC were more likely to have positive UA findings (Table 2). For both cut-offs (≥105 cfu/mL and ≥104 cfu/mL), patients with a positive UC had higher rates of positive UA findings of leukocyte esterase (LE) (36.4% vs. 7.0%, P=0.007 and 28.6% vs. 5.9%, P<0.001, respectively), nitrite (18.2% vs. 0.4%, P=0.004 and 7.1% vs. 0.4%, P=0.026, respectively), pyuria (45.5% vs. 12.8%, P=0.011 and 35.7% vs. 11.7%, P=0.001, respectively) and bacteriuria (63.6% vs. 15.8%, P=0.001 and 57.1% vs. 13.3%, P<0.001, respectively), than those with a negative UC. All in all, for both cut-offs, UC was mostly positive amongst patients with abnormal UA findings (72.7% vs. 24.9%, P=0.002 and 67.9% vs. 22.3%, P<0.001, respectively).

Table 2   UA results of patients with positive and negative urine cultures at cut-offs ≥105 cfu/mL and ≥104 cfu/mL, n (%)

VariablesCut-off ≥105 cfu/mLCut-off ≥104 cfu/mL
Positive UCs
(n=11)
Negative UCs
(n=273)
P-valuePositive UCs
(n=28)
Negative UCs
(n=256)
P-value
Leukocyte esterase
Positive
Negative
4 (36.4)
7 (63.6)
19 (7.0)
254 (93.0)
0.0078 (28.6)
20 (71.4)
15 (5.9)
241 (94.1)
<0.001
Nitrite
Positive
Negative
2 (18.2)
9 (81.8)
1 (0.4)
272 (99.6)
0.0042 (7.1)
26 (92.9)
1 (0.4)
255 (99.6)
0.026
WBC (pyuria)
Positive
Negative
5 (45.5)
6 (54.5)
35 (12.8)
238 (87.2)
0.01110 (35.7)
18 (64.3)
30 (11.7)
226 (88.3)
0.001
Bacteria (bacteriuria)
Positive
Negative
7 (63.6)
4 (36.4)
43 (15.8)
230 (84.2)
0.00116 (57.1)
12 (42.9)
34 (13.3)
222 (86.7)
<0.001
Urine analysis
Positive
Negative
8 (72.7)
3 (27.3)
68 (24.9)
205 (75.1)
0.00219 (67.9)
9 (32.1)
57 (22.3)
199 (77.7)
<0.001

WBC: white blood cell, considered positive if ≥ 5 cells/hpf; urine analysis was considered positive if any of the above findings were positive.

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On the other hand, UA was negative in 27.3% and 32.1% of patients with a positive UC at the cut-offs ≥105 cfu/mL and ≥104 cfu/mL, respectively. More specifically, at cut-offs ≥105 cfu/mL and ≥104 cfu/mL, positive UC groups had no UA finding of LE in 63.6% and 71.4% of cases, nitrite in 81.8% and 92.9% of cases, pyuria in 54.5% and 64.3% of cases, and bacteriuria in 36.4% and 42.9% of cases, respectively. Moreover, bacteria were detected in the UA of 15.8% and 13.3% of patients with a negative UC at ≥105 cfu/mL and ≥104 cfu/mL, respectively.

UA sensitivity analysis for UTI diagnosis

To diagnose UTI at UC cut-offs ≥105 cfu/mL and ≥104 cfu/mL, bacteriuria was found to be the most sensitive UA finding (63.6% and 57.1%, respectively), followed by pyuria (45.5% and 35.7%, respectively), LE (36.4% and 28.6%, respectively), and nitrite as least sensitive (18.2% and 7.1%, respectively) (Tables 3 and 4). Positive predictive value (PPV) was the highest for nitrite (66.7%) followed by LE (17.4% and 34.8%, respectively), bacteriuria (14.0% and 32.0%, respectively), and pyuria (12.5% and 25.0%, respectively). UA was found to be 72.7% sensitive and 75.1% specific in diagnosing UTI in febrile neutropenic adults at the UC cut-off ≥105 cfu/mL, and 67.9% sensitive and 77.7% specific at the UC cut-off ≥104 cfu/mL, with PPVs of 10.5% and 25.0%, respectively.

Table 3   Diagnostic performance of urinalysis findings at a urine culture cut-off ≥105 cfu/mL, % (95% CI)

VariablesSensitivitySpecificityPPVNPV
WBC (pyuria)45.5 (16.8, 76.2)87.2 (82.6, 90.9)12.5 (6.5, 22.7)97.5 (95.9, 98.6)
Leukocyte esterase36.4 (10.9, 69.2)93.0 (89.3, 95.8)17.4 (7.9, 34.0)97.3 (95.9, 98.3)
Nitrite18.2 (2.3, 51.8)99.6 (98.0, 100.0)66.7 (16.4, 95.3)96.8 (95.8, 97.6)
Bacteria (bacteriuria)63.6 (30.8, 89.1)84.3 (79.4, 88.4)14.0 (8.8, 21.6)98.3 (96.3, 99.2)
Urine analysis72.7 (39.0, 94.0)75.1 (69.5, 80.1)10.5 (7.2, 15.1)98.6 (96.3, 99.5)

PPV: positive predictive value; NPV: negative predictive value; WBC: white blood cell; CI: confidence interval; urinalysis was considered positive if any of the above findings were positive.

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Table 4   Diagnostic performance of urinalysis findings at a urine culture cut-off ≥104 cfu/mL, % (95% CI)

VariablesSensitivitySpecificityPPVNPV
WBC (pyuria)35.7 (18.6, 55.9)88.3 (83.7, 92.0)25.0 (15.5, 37.8)92.6 (90.5, 94.3)
Leukocyte esterase28.6 (13.2, 48.7)94.1 (90.5, 96.7)34.8 (19.9, 53.4)92.3 (90.5, 93.9)
Nitrite7.1 (0.9, 23.5)99.6 (97.8, 100.0)66.7 (15.8, 95.3)90.8 (89.9, 91.6)
Bacteria (bacteriuria)57.1 (37.2, 75.5)86.7 (81.9, 90.6)32.0 (23.1, 42.4)94.9 (92.3, 96.6)
Urine analysis67.9 (47.7, 84.1)77.7 (72.1, 82.7)25.0 (19.1, 32.0)95.7 (92.8, 97.4)

PPV: positive predictive value; NPV: negative predictive value; WBC: white blood cell; CI: confidence interval; urinalysis was considered positive if any of the above findings were positive.

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DISCUSSION

FN is a medical emergency in oncology patients. International guidelines have put forth specific protocols for therapy and basic workup at the initial evaluation of these patients.[3,14] Urine testing, although commonly performed, is not well-validated, as there is ambiguity regarding its utility as a routine investigation.

Our study, to the best of our knowledge, is the largest in the region to evaluate the utility of urine studies in asymptomatic (i.e., no urinary signs or symptoms) adult oncology patients presenting with FN to the ED.

In this study, UC was positive in only 3.9% of patients at a cut-off ≥105 cfu/mL and 9.9% at a cut-off ≥104 cfu/mL. This low positive culture rate was not surprising but rather consistent with findings from previous studies, where infections were reportedly documented in only 20%-30% of all FN episodes,[13] and the rate of UTI ranged between 5% and 30% in oncology patients with FN.[6-9,13] Moreover, the low rate of UTI in this patient population can be further attributed to the rarity of a typical clinical picture of UTI leading to a missed diagnosis in many occasions.

One study on adult cancer patients with FN showed that urine studies were more likely to be positive in symptomatic episodes compared with asymptomatic episodes (relative risk [RR]=7.4, P<0.001).[22] Nevertheless, other studies reported higher rates of documented UTI (18.5% to 47.0%) in FN patients without signs or symptoms suggestive of UTI.[13,23] As a matter of fact, in one of those studies, only 2.2% of the patients presented with urinary symptoms, and none of those had significant bacteriuria.[13]

Herein, we conclude that the incidence of UTI in adult cancer patients with FN is low due to a constellation of factors. We also conclude that the presence of signs or symptoms of UTI may or may not be associated with significant bacteriuria and is thus an unreliable parameter.[9,13]

In our study, patients with positive UCs were found to be significantly older and more likely to be females compared with patients with negative UCs. This is in line with findings in the general population, where the prevalence of asymptomatic bacteriuria is known to increase with age and female gender.[24] These findings are also coherent with results from previous studies on febrile neutropenic oncology patients, showing that the majority of patients with UTI were females.[6,9]

UCs were more likely to be positive in patients with abnormal UA findings. In our study, more than two-thirds of patients with positive UCs had a positive UA. A previous study reported an abnormal UA in 14.5% of patients with a positive UC and severe neutropenia,[13] and 43.0% of patients with a positive UC and moderate to severe neutropenia.[22] The rates reported in our study are similar to those of a study on pediatric oncology patients with confirmed UTI, where 69% of UA samples were abnormal, and 85% had an absolute neutrophil count (ANC) >500 cells/mm3.[23] These differences in the presence of a UA abnormality may be attributed to the severity of neutropenia as well as the urine collection technique; a higher ANC and bladder catheterization are significantly associated with the presence of pyuria.[18]

Moreover, in healthy patients, a negative UA result generally has a high negative predictive value (NPV). In our study, however, almost one-third of UTI patients had normal UA findings. UA was negative in 27.3% and 32.1% of patients with a positive UC at the cut-offs ≥105 cfu/mL and ≥ 104 cfu/mL, respectively. Hence, negative UA findings should be interpreted with caution in febrile neutropenic patients due to the high false negative rates.

The most common UA abnormality in our study was bacteriuria. This was similarly described in a previous study on adult patients with FN.[13] Here, it is worthwhile to note that 13.3% to 15.8% of negative UCs in our study were found to be associated with bacteriuria. Consequently, it might be argued that significant bacteriuria in the absence of pyuria reflects contamination, particularly in patients where urine was not collected by catheterization.[18]

It is well-known that patients with FN have leukopenia and a depressed inflammatory response, limiting the number of white blood cells (WBCs) excreted into the urine. LE is generally produced by neutrophils and may signal the presence of urine WBCs in patients with UTI.[25] Klaassen et al[18] reported the presence of pyuria in 4% of neutropenic children with UTI as compared with 68% of non-neutropenic children. Likewise, in a study on pediatric oncology patients with confirmed UTI, pyuria and LE were reported in 39% and 51% of all samples but only in 15% and 23% of neutropenic patients’ samples, respectively.[23] For this reason, findings of pyuria and LE may be difficult to interpret in a neutropenic patient as more than half of the patients with UTI may show no pyuria or LE.

The presence of nitrite was the least sensitive UA finding for the diagnosis of UTI in our study, followed by LE, pyuria, and bacteriuria. Similar findings were conveyed in a previous study done on pediatric cancer patients, where pyuria had a higher sensitivity (80.0%) compared with nitrite (60.0%).[26] Additionally, the sensitivities of UA findings in our study population seemed to be lower compared with the general population. In fact, the sensitivity of LE was 28.6% (UC cut-off ≥104 cfu/mL) and 36.4% (UC cut-off ≥105 cfu/mL) compared with 72.4% to 77.0% in the general population,[27] nitrite were found to be sensitive at 7.1% to 18.2% compared with 16.1% to 19.9% in the general population,[27] and pyuria was sensitive at 35.7% to 45.5% compared with 84.0% to 84.4% in general population.[28] Therefore, we can conclude that neutropenia affects the sensitivity of UA findings in predicting UTI.

Although nitrite was found to be the least sensitive, the presence of nitrite had a high PPV (66.7%). A positive nitrite test serves as a strong predictor of UTI but needs to be confirmed through a positive UC. The presence of nitrite was also the most specific finding (99.6%). However, in view of sensitivity, the nitrite test alone cannot be used to rule out UTI. In fact, even in the general population, a nitrite test may be negative if the causative organism is not nitrate-reducing (e.g., Enterococci, S. saprophyticus, Acinetobacter).[27] In contrast, the PPV of LE (17.4% to 34.8%) and WBC (12.5% to 25.0%) in urine was comparatively lower than that of nitrite, similar to reports by Grigg et al.[22] This further consolidates that UA findings of pyuria and LE are less accurate markers in neutropenic patients.

In our study, at a UC cut-off ≥105 cfu/mL, UA was 72.7% sensitive and 75.1% specific for the diagnosis of UTI. At a UC cut-off ≥104 cfu/mL, sensitivity decreased to 67.9% and specificity increased to 77.7%. Lowering the cut-off increased the PPV from 10.5% to 25.0% with a small decrease from 98.6% to 95.7% in NPV. UA findings of bacteria, nitrite, LE, and pyuria were all less sensitive but more specific. As such, a positive UA result would be interpreted more accurately as significant bacteriuria at a UC cut-off ≥104 cfu/mL.

Limitations

The results of our study should be considered its limitations. First, this study was single centered with small sample size (a total of 39 positive UCs at both cut-offs). This could affect the external validity and generalizability of our results to other patient populations. Second, it was retrospective in nature and was thus associated with resource constraints and data unavailability, including data on the method of urine specimen collection (clean catch vs. bladder catheterization) and the time a urine specimen was sampled with respect to the time of antibiotics initiation. Third, data on hematuria and transient proteinuria were not collected, although an association between those and UTI had been established.[27,29]

CONCLUSIONS

The incidence of UTI in adult cancer patients with FN is low. The presence of signs or symptoms of UTI may or may not be associated with significant bacteriuria and is thus an unreliable parameter. Pyuria and LE have limited sensitivities in detecting UTI in febrile neutropenic patients. Additionally, a positive UC in cancer patients with FN and without localizing signs or symptoms of UTI may not be associated with UA abnormalities. Therefore, a routine urine test is often unwarranted and inefficient in diagnosing UTI in this population. Prospective large-scale studies are needed to confirm our results. Current recommendations suggesting a pivotal role of urine studies in the initial workup of these patients can be revised.

Funding: This study did not receive any funding.

Ethical approval: Ethical approval was obtained from the Institutional Review Board at AUBMC under the protocol number (BIO-2018-0455).

Conflicts of interests: The authors declare that they have no competing interests.

Contributors: HZ determined the concept of the study and was a major contributor to the study design, data analysis, interpretation and manuscript production. All authors read and approved the final manuscript.

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Support Care Cancer. 1994; 2(6):400-2.

DOI:10.1007/BF00344056      URL     PMID:7858935      [Cited within: 3]

A sample of 100 consecutive febrile neutropenic episodes in cancer patients in Kuwait was studied. Acute leukaemias (44%) and lymphomas (29%) were the most frequent underlying cancers; 21 bacteraemis (gram-positive 10, gram-negative 9, polymicrobial 2) were encountered. Staphylococcous epidermidis and Escherichia coli were the commonest organisms. Urinary tract infection occurred in 30% of the microbiologically documented cases. A total of 84 episodes responded to therapy and 9 of the 14 deaths were secondary to infection.

Engelhart S, Glasmacher A, Exner M, Kramer MH .

Surveillance for nosocomial infections and fever of unknown origin among adult hematology-oncology patients

Infect Control Hosp Epidemiol. 2002; 23(5):244-8.

DOI:10.1086/502043      URL     PMID:12026148      [Cited within: 1]

OBJECTIVE: To determine the incidence of nosocomial infections (NIs) and fever of unknown origin among adult hematology-oncology patients. DESIGN: Prospective surveillance study. SETTING: The 18-bed hematology-oncology unit at the University Hospital Bonn, Bonn, Germany. PATIENTS: All hematology-oncology patients admitted during a total of 8 months in 1998 and 1999. METHODS: Standardized surveillance system based on the Centers for Disease Control and Prevention's National Nosocomial Infections Surveillance system. Rates of NI and fever of unknown origin were calculated for patient-days and patient-days at risk (ie, days with neutropenia of < 500/mm3 or leukopenia of < 1,000/mm3). RESULTS: Of 116 patients hospitalized for a total of 4,002 days (172 admissions; mean length of stay, 25.2 days), 32 (27.6%) had a total of 44 documented NIs (19 bloodstream infections, 15 pneumonias, 7 urinary tract infections, and 3 others). In addition, 33 fevers of unknown origin were documented in 28 patients. No patient had thrush while receiving antifungal prophylaxis. The overall rates for NI and fever of unknown origin were 11.0 and 8.2 per 1,000 patient-days (25.3 and 15.4 per 1,000 patient-days at risk), respectively. The risks for NI and fever of unknown origin were significantly higher during neutropenic days, with 34 (77.3%) of the 44 NIs and 22 (66.7%) of the 33 fevers of unknown origin occurring during 1,345 patient-days at risk. CONCLUSIONS: Prospective surveillance for NIs on hematology-oncology units should include fever of unknown origin as the single most common and clinically important entity. For a meaningful comparison of surveillance data for hematology-oncology patients, the reported infection rates should include rates based on days with neutropenia, for which days with leukopenia could serve as a surrogate marker under routine conditions.

Hamzeh F, Kanj SS, Uwaydah M .

Febrile neutropenia in cancer patients in a tertiary care medical center in Lebanon: microbial spectrum and outcome.

[J] Med Liban. 2000; 48(3):136-42.

[Cited within: 1]

Sandoval C, Sinaki B, Weiss R, Munoz J, Ozkaynak MF, Tugal O , et al.

Urinary tract infections in pediatric oncology patients with fever and neutropenia

Pediatr Hematol Oncol. 2012; 29(1):68-72.

DOI:10.3109/08880018.2011.617809      URL     PMID:22304012      [Cited within: 6]

The relevancy of the urinary tract as a source of infection during febrile neutropenia is not known. The authors sought to determine the frequency of urinary tract infections (UTIs) in pediatric cancer patients with febrile neutropenia. Urine was collected from a mid-stream void before the administration of antibiotics. Demographic, clinical, and laboratory data were collected. The frequency of UTI and usefulness of urinalysis and localizing signs in predicting UTI in pediatric cancer patients with fever and neutropenia were determined. Forty-five patients had 58 febrile neutropenic episodes eligible for study participation. No patient presented with localizing signs. The urinalysis was negative in 53 episodes and positive in 5 episodes. Four patients had 5 UTIs. The frequency of UTI was 8.6% (5 of 58 febrile neutropenia episodes). Four patients had bacteremia, none of whom had a UTI. The sensitivity, specificity, and negative predictive value of urinalysis was 40%, 94%, and 94%, respectively, and for localizing signs was undefined, 100%, and 91%, respectively. UTI is as common as bacteremia in the current pediatric cancer patients with fever and neutropenia. Urinalysis and urine culture should be obtained routinely as part of the diagnostic evaluation of patients with fever and neutropenia.

de Lalla F .

Antibiotic treatment of febrile episodes in neutropenic cancer patients. Clinical and economic considerations

Drugs. 1997; 53(5):789-804.

DOI:10.2165/00003495-199753050-00005      URL     PMID:9129866      [Cited within: 1]

The increased frequency of infections caused by Gram-positive microorganisms, and the expansion of resistant pathogens resulting from institutional therapeutic practices, represent some of the emerging issues of empirical drug treatment of cancer patients with febrile neutropenia. However, the therapeutic strategies for the treatment of these patients have progressed remarkably over the last decade. Individual therapy in the light of the principal clinical features (in particular, the degree and estimated duration of neutropenia, as well the presence of other potential factors favouring infection such as long-standing intravascular catheters) and local microbial ecology have emerged as the leading concepts. Empirical drug monotherapy has been recognised as a feasible alternative to combination therapy, at least in selected low-risk patients. The indiscriminate use of empirical glycopeptides should be discouraged to prevent the emergence of resistant bacteria, especially in centres where methicillin-resistant staphylococci have not yet become a major issue. Empirical antifungal therapy with amphotericin B is still essential for a successful outcome in case of fever persistence or recurrence. Finally, selected febrile neutropenic patients who exhibit a better prognosis can be handled on an outpatient basis. The prophylactic use of haemopoietic growth factors has been shown to augment cost savings substantially in the management of neutropenic patients via a reduction in the duration and severity of the neutropenia, as well as infectious complications. Although data from economic analyses are not yet available, some cost-containment strategies such as outpatient treatment, monotherapy, and use of more convenient antibiotic combinations may lead to a reduction of therapy expenditures for febrile episodes in these patients.

Gaytán-Martı́nez J, Mateos-Garcı́a E, Sánchez-Cortés E, González-Llaven J, Casanova-Cardiel LJ, Fuentes-Allen JL .

Microbiological findings in febrile neutropenia

Arch Med Res. 2000; 31(4):388-92.

DOI:10.1016/s0188-4409(00)00080-1      URL     PMID:11068081      [Cited within: 1]

BACKGROUND: This study was carried out to assess the isolation rate of bacterial and fungal causative agents in Mexican neutropenic adults with hematological neoplasia. METHODS: A prospective observational survey involving 120 consecutive episodes of febrile neutropenia during 1 year was carried out. These episodes were observed in 630 patients discharged with diagnoses of leukemia or lymphoma, or after bone-marrow transplantation. RESULTS: At least one pathogen was isolated in 42 of 120 episodes (35%), and was present in 39 patients with acute myeloid leukemia (AML) (43%), acute lymphoblastic leukemia (ALL) (23%), and in patients who underwent bone-marrow transplantation (20%). Primary bacteremia was the most frequent cause of fever (24 episodes, 57%), followed by intravascular device-related infections (5 episodes, 17%), and soft-tissue infections (5 episodes, 15%). Escherichia coli (33%) was the most frequently isolated agent of primary bacteremia, followed by coagulase-negative Staphylococcus (29%), and Klebsiella oxytoca (16%). Fungal infection was responsible for five events (4%): two episodes of pneumonia (Penicillium marneffei and Aspergillus fumigatus, one event each); two cases of fungemia, one due to Candida tropicalis and one to Rhodotorula gluttinis, and one cryptococcal meningitis event. CONCLUSIONS: The isolation rate, approximately 30%, was in accordance with previous reports; similar percentages of Gram-positive and Gram-negative isolates were found. A remarkably low rate of viridans group streptococci and fungal agents was observed, despite the fact that neutropenia is the main risk factor for infection due to these agents. Studies reporting local microbiological findings are necessary because they support an antibiotic choice for prophylaxis or therapy more accurately than reports from other areas.

Pizzo PA .

Management of fever in patients with cancer and treatment-induced neutropenia. N Engl

[J] Med. 1993; 328(18):1323-32.

[Cited within: 1]

Steinrücken J, Pabst T, Zimmerli S, Marschall J .

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

Infect Dis (Lond). 2016; 48(11-12):872-4.

[Cited within: 8]

Freifeld AG, Bow EJ, Sepkowitz KA, Boeckh MJ, Ito JI, Mullen CA , et al.

Clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer: 2010 update by the Infectious Diseases Society of America.

Clin Infect Dis. 2011; 52(4):e56-93.

DOI:10.1093/cid/cir073      URL     [Cited within: 3]

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia.
Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving.
What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens.
Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care-associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Hughes WT, Armstrong D, Bodey GP, Bow EJ, Brown AE, Calandra T , et al.

2002 guidelines for the use of antimicrobial agents in neutropenic patients with cancer

Clin Infect Dis. 2002; 34(6):730-51.

DOI:10.1086/339215      URL     PMID:11850858      [Cited within: 1]

Khan AR, Khan S, Zimmerman V, Baddour LM, Tleyjeh IM .

Quality and strength of evidence of the Iinfectious Diseases Society of America clinical practice guidelines

Clin Infect Dis. 2010; 51(10):1147-56.

DOI:10.1086/656735      URL     PMID:20946067      [Cited within: 1]

OBJECTIVE: To describe the distribution and temporal trends of the quality and strength of evidence supporting recommendations in the Infectious Diseases Society of America (IDSA) clinical practice guidelines. METHODS: Guidelines either issued or endorsed by IDSA from March 1994 to July 2009 were evaluated using the IDSA-US Public Health Service Grading System. In this system, the letters A-E signify the strength of the recommendation, and numerals I-III indicate the quality of evidence supporting these recommendations. The distribution of the guideline recommendations among strength of recommendation and quality of evidence classes was quantified. Temporal changes between the first and current guideline version were evaluated. RESULTS: Approximately one-half (median, 50.0%; interquartile range [IQR], 38.1%-58.6%) of the recommendations in the current guidelines are supported by level III evidence (derived from expert opinion). Evidence from observational studies (level II) supports 31% of recommendations (median, 30.9%; IQR, 23.3%-43.2%), whereas evidence based on >/= 1 randomized clinical trial (level I) constitutes 16% of the recommendations (median, 15.8%; IQR, 5.8%-28.3%). The strength of recommendation was mainly distributed among classes A (median, 41.5%; IQR, 28.7%-55.6%) and B (median, 40.3%; IQR, 27.1%-47.9%). Among guidelines with >/= 1 revised version, the recommendations moved proportionately toward more level I evidence (+12.4%). Consequently, there was a proportional increase in class A recommendations (+11.1%) with a decrease in class C recommendations (-23.5%). CONCLUSIONS: The IDSA guideline recommendations are primarily based on low-quality evidence derived from nonrandomized studies or expert opinion. These findings highlight the limitations of current clinical infectious diseases research that can provide high-quality evidence. There is an urgent need to support high-quality research to strengthen the evidence available for the formulation of guidelines.

Lee DH, Vielemeyer O .

Analysis of overall level of evidence behind Infectious Diseases Society of America practice guidelines

Arch Intern Med. 2011; 171(1):18-22.

DOI:10.1001/archinternmed.2010.482      URL     [Cited within: 1]

Background: Clinical practice guidelines are developed to assist in patient care. Physicians may assume that following such guidelines means practicing evidence-based medicine. However, the quality of supporting literature can vary greatly.
Methods: We analyzed the strength of recommendation and overall quality of evidence behind 41 Infectious Diseases Society of America (IDSA) guidelines released between January 1994 and May 2010. Individual recommendations were classified based on their strength of recommendation (levels A through C) and quality of evidence (levels I through III). Guidelines not following this format were excluded from further analysis. Evolution of IDSA guidelines was assessed by comparing 5 recently updated guidelines with their earlier versions.
Results: In the 41 analyzed guidelines, 4218 individual recommendations were found and tabulated. Fourteen percent of the recommendations were classified as level I, 31% as level II, and 55% as level III evidence. Among class A recommendations (good evidence for support), 23% were level I (>= 1 randomized controlled trial) and 37% were based on expert opinion only (level III). Updated guidelines expanded the absolute number of individual recommendations substantially. However, few were due to a sizable increase in level I evidence; most additional recommendations had level II and III evidence.
Conclusions: More than half of the current recommendations of the IDSA are based on level III evidence only. Until more data from well-designed controlled clinical trials become available, physicians should remain cautious when using current guidelines as the sole source guiding patient care decisions. Arch Intern Med. 2011;171(1):18-22

Klaassen IL, de Haas V, van Wijk JA, Kaspers GJ, Bijlsma M, Bökenkamp A .

Pyuria is absent during urinary tract infections in neutropenic patients

Pediatr Blood Cancer. 2011; 56(5):868-70.

DOI:10.1002/pbc.22799      URL     [Cited within: 4]

To investigate the diagnostic significance of a normal urine sediment in the work-up for fever of unknown origin in neutropenia. Urinary tract infection was defined as >= 10(5) urinary pathogens in the absence of another focus. Pyuria was found in only 1/23 neutropenic episodes compared to 21/31 in controls (P < 0.0001). Pediatr Blood Cancer 2011;56:868-870. (C) 2010 Wiley-Liss, Inc.

Masaoka T .

Evidence-based recommendations for antimicrobial use in febrile neutropenia in Japan: executive summary

Clin Infect Dis. 2004; 39(s1):S49-52.

DOI:10.1086/cid.2004.39.issue-s1      URL     [Cited within: 1]

Santolaya ME, Alvarez AM, Avilés CL, Becker A, Mosso C, O’Ryan M, et al.

Admission clinical and laboratory factors associated with death in children with cancer during a febrile neutropenic episode

Pediatr Infect Dis J. 2007; 26(9):794-8.

DOI:10.1097/INF.0b013e318124aa44      URL     PMID:17721373      [Cited within: 1]

BACKGROUND: Early identification of children with cancer at risk for death during a febrile neutropenic (FN) episode may increase their possibility for survival. Our aim was to identify at the time of admission, clinical and laboratory variables differing significantly among children who survived or died during a FN episode. METHODS: In a prospective, multicenter study, children admitted with a high-risk FN episode were uniformly evaluated at enrollment and managed according to a national consensus protocol. Medical charts of children who died were evaluated to determine whether the death could be associated with an infection. Admission clinical and laboratory variables significantly associated with death were identified. RESULTS: A total of 393 (70%) of 561 FN episodes evaluated from June 2004 to December 2005 were classified as high risk for invasive bacterial infection, of which 14 (3.6%) resulted in an infectious-related death. Deaths occurred from 2 to 27 days after admission, and most dying children were admitted with relapse of acute lymphocytic leukemia (36%), hypotension (71%), and a diagnosis of sepsis (79%), compared with surviving children (16%, 20%, and 5% respectively, P < 0.001). Children who died were admitted with lower absolute neutrophil count (P < 0.001) and absolute monocytes count levels (P = 0.008), higher blood urinary nitrogen (P = 0.03) and C-reactive protein values (P < 0.001), and had more positive cultures (79% versus 32%, P = 0.008). CONCLUSIONS: We identified early clinical and laboratory findings significantly associated with death occurring at a later stage. Routine evaluation of these variables may prove to be useful in the early identification of children with a high-risk FN episode at risk for death.

Roberts KB, Wald ER .

The diagnosis of UTI: colony count criteria revisited

Pediatrics. 2018; 141(2):e20173239.

DOI:10.1542/peds.2017-3239      URL     PMID:29339563      [Cited within: 2]

Grigg SE, Date P, Loh Z, Estacio O, Johnson DF, Hawkes EA , et al.

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

Support Care Cancer. 2019; 27(4):1223-7.

DOI:10.1007/s00520-018-4476-7      URL     PMID:30259115      [Cited within: 3]

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 x 10(9)/L and fever > 37.5 degrees 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 > 10(5) 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.

Hirmas N, Mubarak S, Sultan I .

Patterns of microbial growth in urine cultures in a pediatric hematology/oncology unit over a one-year period: a single institution study. Int

[J] Pediatr Adolesc Med. 2017; 4(3):95-9.

[Cited within: 3]

Nicolle LE .

The paradigm shift to non-treatment of asymptomatic bacteriuria

Pathogens. 2016; 5(2):E38.

DOI:10.3390/pathogens5020038      URL     PMID:27104571      [Cited within: 1]

Asymptomatic bacteriuria, also called asymptomatic urinary infection, is a common finding in healthy women, and in women and men with abnormalities of the genitourinary tract. The characterization and introduction of the quantitative urine culture in the 1950s first allowed the reliable recognition of asymptomatic bacteriuria. The observations that a substantial proportion of patients with chronic pyelonephritis at autopsy had no history of symptomatic urinary infection, and the high frequency of pyelonephritis observed in pregnant women with untreated asymptomatic bacteriuria, supported a conclusion that asymptomatic bacteriuria was harmful. Subsequent screening and long term follow-up programs for asymptomatic bacteriuria in schoolgirls and women reported an increased frequency of symptomatic urinary tract infection for subjects with asymptomatic bacteriuria, but no increased morbidity from renal failure or hypertension, or increased mortality. Treatment of asymptomatic bacteriuria did not decrease the frequency of symptomatic infection. Prospective, randomized, comparative trials enrolling premenopausal women, children, elderly populations, patients with long term catheters, and diabetic patients consistently report no benefits with antimicrobial treatment of asymptomatic bacteriuria, and some evidence of harm. Several studies have also reported that antimicrobial treatment of asymptomatic bacteriuria increases the short term risk of pyelonephritis. Current investigations are exploring the potential therapeutic intervention of establishing asymptomatic bacteriuria with an avirulent Escherichia coli strain to prevent symptomatic urinary tract infection for selected patients.

Simerville JA, Maxted WC, Pahira JJ .

Urinalysis: a comprehensive review

Am Fam Physician. 2005; 71(6):1153-62.

URL     PMID:15791892      [Cited within: 1]

A complete urinalysis includes physical, chemical, and microscopic examinations. Midstream clean collection is acceptable in most situations, but the specimen should be examined within two hours of collection. Cloudy urine often is a result of precipitated phosphate crystals in alkaline urine, but pyuria also can be the cause. A strong odor may be the result of a concentrated specimen rather than a urinary tract infection. Dipstick urinalysis is convenient, but false-positive and false-negative results can occur. Specific gravity provides a reliable assessment of the patient's hydration status. Microhematuria has a range of causes, from benign to life threatening. Glomerular, renal, and urologic causes of microhematuria often can be differentiated by other elements of the urinalysis. Although transient proteinuria typically is a benign condition, persistent proteinuria requires further work-up. Uncomplicated urinary tract infections diagnosed by positive leukocyte esterase and nitrite tests can be treated without culture.

Munyi ST, Macharia WM, Alwar AJ, Njeru EK .

Screening for urinary tract infection in children with cancer

East Afr Med J. 1998; 75(5):264-7.

URL     PMID:9746994      [Cited within: 1]

Neutropaenia and immunosuppression place children on treatment for malignancies at a high risk for infections. We undertook to determine the prevalence of urinary tract infection (UTI) in children on treatment for cancer at the Kenyatta National Teaching and Referral hospital. With the understanding that many laboratories in the rural areas of the country lack appropriate facilities for confirmation of UTI, it was also important to evaluate simple and inexpensive screening methods against a

Mehnert-Kay SA .

Diagnosis and management of uncomplicated urinary tract infections

Am Fam Physician. 2005; 72(3):451-6.

URL     PMID:16100859      [Cited within: 4]

Most uncomplicated urinary tract infections occur in women who are sexually active, with far fewer cases occurring in older women, those who are pregnant, and in men. Although the incidence of urinary tract infection has not changed substantially over the last 10 years, the diagnostic criteria, bacterial resistance patterns, and recommended treatment have changed. Escherichia coli is the leading cause of urinary tract infections, followed by Staphylococcus saprophyticus. Trimethoprim-sulfamethoxazole has been the standard therapy for urinary tract infection; however, E. coli is becoming increasingly resistant to medications. Many experts support using ciprofloxacin as an alternative and, in some cases, as the preferred first-line agent. However, others caution that widespread use of ciprofloxacin will promote increased resistance.

Kayalp D, Dogan K, Ceylan G, Senes M, Yucel D .

Can routine automated urinalysis reduce culture requests?

Clin Biochem. 2013; 46(13-14):1285-9.

DOI:10.1016/j.clinbiochem.2013.06.015      URL     [Cited within: 1]

Objectives: There are a substantial number of unnecessary urine culture requests. We aimed to investigate whether urine dipstick and microscopy results could accurately rule out urinary tract infection (UTI) without urine culture.
Design and methods: The study included a total of 32 998 patients (11 928 men and 21 070 women, mean age: 39 +/- 32 years) with a preliminary diagnosis of UTI and both urinalysis and urinary culture were requested. All urine cultures were retrospectively reviewed; association of culture positivity with a positive urinalysis result for leukocyte esterase (LE) and nitrite in chemical analysis and pyuria (WBC) and bacteriuria in microscopy was determined. Diagnostic performance of urinalysis parameters for detection of UTI was evaluated.
Results: In total, 758 (2.3%) patients were positive by urine culture. Out of these culture positive samples, ratios of positive dipstick results for LE and nitrite were 71.0% (n = 538) and 17.7% (n = 134), respectively. The positive microscopy results for WBC and bacteria were 68.2% (n = 517) and 78.8% (n = 597), respectively. Negative predictive values for LE, nitrite, bacteriuria and WBC were very close to 100%.
Conclusions: Most of the samples have no or insignificant bacterial growth. Urine dipstick and microscopy can accurately rule out UTI. Automated urinalysis is a practicable and faster screening test which may prevent unnecessary culture requests for majority of patients. (c) 2013 The Canadian Society of Clinical Chemists. Published by Elsevier Inc.

Bharara T, Sharma A, Gur R, Duggal SD, Jena PP, Kumar A.

Predictive role of proteinuria in urinary tract infection

J Clin Diagn Res. 2017;11(10):DC01-3.

[Cited within: 1]

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