ROLE OF URINE DIPSTICK IN SCREENING URINARY TRACT INFECTION IN CHILDREN BETWEEN 1 MONTH TO 36 MONTHS OF AGE

7 Feb 2025 12 a.m. 12 a.m.
WCN25-AB-1803, Poster Board= FRI-630

Introduction:

Prompt diagnosis of urinary tract infection (UTI) in children is needed to initiate treatment but is difficult to establish without urine testing, and reliance on culture leads to delay. Urine dipsticks are often used as an alternative to microscopy, although the diagnostic performance of dipsticks at different ages has not been established. With this potentially avoidable morbidity, it is crucial to have the correct diagnosis. This study evaluates the role of urine dipstick in screening urinary tract infection between 1 month to 36 months of age, which is a specific age group where the role of urine dipstick in screening urinary tract infection has not yet  studied

Methods:

Study design- Descriptive study

Place of study-Outpatient department and Pediatric ward in Mehta’s Multispecialty Hospitals India Pvt Ltd.

Study period :October 2022 – October 2023

Study population: Children between 1 month to 36 months of age in Mehta’s Multispecialty Hospital Outpatient department and Pediatric ward.

Inclusion criteria: Children between 1month to 36 months of age with ,Fever without focus, Fever in children with phimosis / vulval synechiae, Fever in children with symptoms suggestive of urinary tract infection like abdominal pain, vomiting, dysuria, increased frequency in urination.

Exclusion criteria: Patients whose parents didn’t give consent for the study, Patients who were sick and admitted in PICU,Patients who were already on antibiotic course before presenting to hospital. 

Based on previous study on Dipstick Screening for Urinary Tract Infection in Febrile Infants by Glissmeyer,et al. the sensitivity of the Dipstick among infants aged 29 to 90 days (90.4%; 95% CI: 90.0%–90.8%) and the sample size calculated was 142 with power of the study 85% (β = 15%) and confidence of result 95 %(type 1 error α= 5%) with the Open epi software version 3.01. Allowing 10% of dropout rate, total sample size was 150.

SIEMENS MULTISTIX 10G urine dipstick and urine chemistry analyzer was used for the study. The reagent strip contains tests pads for protein, blood, leukocyte, nitrite, glucose, ketone, pH, specific gravity, bilirubin and urobilinogen. In our study the parameters considered in dipstick analysis are nitrites and leukocyte esterase. Reading time for nitrites and blood is one min and two min for leukocyte esterase and the test was analyzed by trained personnel. Leukocyte esterase and nitrite was considered negative or positive including any result >- trace, as determined by colorimetric interpretation of the dipstick by a semiautomated urine chemistry analyzer. Urine microscopic analysis: Microscopic tests (WBCs and bacteria) were performed by microbiologist using uniform standardized methods on centrifuged urine specimens. WBCs were considered positive if the laboratory reported >10 WBCs per HPF. Bacteria considered negative or positive including any 1> (rare) bacteria per HPF. Urine culture and sensitivity: Urine culture (gold standard) was done for all children included in study. The cultures were done using blood agar and MacConkey agar plates. The cultures were read after 24 hours of incubation at 37°C. Samples that grew more than one microorganism were considered to be mixed growth and were excluded from the study.Colony count in urine culture was considered significant according to the method of urine sample collected

Results:

Diagnostic characteristics of the urine dipstick (Nitrites) as a screening test versus the gold standard of urine culture
 

Sensitivity

-

36.62%

Specificity

-

100%

Positive Predictive Value

-

100%

Negative Predictive Value

-

63.41%

Diagnostic Accuracy

-

69.8%

Cohen's Kappa

-

0.3769


 

Out of the 71culture proven UTI, 26 had nitrite positivity also with dipstick, giving rise to the Sensitivity of 36.62 %. All the 78 children who found to have no growth in urine were negative for nitrites by dip stick as well, leading to 100% Specificity. All the 26 children who showed nitrites in the urine were culture positive too and hence the positive predictive value is 100 % and among 123 children negative for urinary nitrites by dip stick, 78 children did not grow any organism in urine giving rise to the negative predictive value of 69.8 %

A total of149children between 1 Month to 36 months of age was included in the study. Out of 149 children, 51 (34.2%) were males and 98 (65.8%) were females.

Variables

Number

Percentage

Age Distribution(months)

   

Median age (IQR)

12.00 (8 – 30)

 

Minimum age

2

 

Maximum age

36

 

Gender

   

Male

51

34.2 %

Female

98

65.8 %

Total

149

100 %

The median age of the study participants was 12 [IQR: 8–30] months; the minimum age was 2 months; and the maximum age was 36 months. The majority of the children were female viz. 98 (65.8%), and 51 (34.2%) were males

Fever with/Without FSO

Number

Percentage

Fever with symptoms suggestive of UTI

99

66.4 %

Fever without focus

50

33.6 %

Total

149

100 %

 

Phimosis /Vulvalsynechiae

Number

Percentage

Normal

108

72.5 %

Phimosis

14

9.4 %

Vulvalsynechiae

27

18.1 %

Total

149

100 %

 

Urine collection method

Number

Percentage

Catheterized sample

29

19.5 %

Midstream clean catch

75

50.3 %

Supra pubic aspirate

45

30.2 %

Total

149

100 %

 

Urine routine test

Number

Percentage

Urine color

   

Pale yellow

113

75.8 %

Straw yellow

36

24.2 %

Appearance

   

Clear

100

67.1 %

Turbid

49

32.9 %

Pus cells under high power field of microscope

   

2-3.

80

53.7 %

2-4.

10

6.7 %

3-4.

15

10.1 %

3-5.

12

8.1 %

Plenty

32

21.5 %

Epithelial cells

   

1-2.

68

45.6 %

10-12.

8

5.4 %

2-3.

45

30.2 %

4-6.

18

12.1 %

8-10.

10

6.7 %

RBC's

   

1-2.

49

32.9 %

2-3.

64

43.0 %

6-8.

10

6.7 %

NIL

26

17.4 %

PH

   

Acidic

149

100 %

Mean specific gravity ± SD

1.011 ± 0.003

 

 

Urine albumin

   

1+

24

16.1 %

2+

10

6.7 %

Nil

83

55.7 %

Trace

32

21.5 %

Urine sugar

   

Nil

149

100 %

Nitrites

   

Positive

26

17.4 %

Negative

123

82.6 %

Leucocytes

   

Positive

77

51.7 %

Negative

72

48.3 %

Grade

   

1+

40

26.8 %

2+

22

14.8 %

3+

12

8.1 %

NIL

75

50.3 %

Total

149

100 %

With urine dipstick, Nitrites was positive for 26 (17.4%) children and leucocytes was positive in 77 (51.7%) children 

URINE CULTURE

Number

Percentage

Urine culture report

   

Positive

71

47.7 %

Negative

78

52.3 %

Organisms

   

Escherichia coli

16

10.7%

Enterobacter Cloacae

1

0.7%

Enterococcus Faecaium

1

0.7%

Enterococcus Faecalis

5

3.4 %

Extended spectrum beta-lactamase

Escherichia coli (ESBL E Coli)

35

23.5%

Klebsiella pneumoniae

6

4.0%

MDR Ecoli

4

2.7%

Proteus mirabilis

2

1.3%

Pseudomonas aeruginosa

1

0.7%

Total

149

100 %

 

Diagnostic characteristics of the urine dipstick (Nitrites) as a screening test versus the gold standard of urine culture:

Sensitivity

-

36.62%

Specificity

-

100%

Positive Predictive Value

-

100%

Negative Predictive Value

-

63.41%

Diagnostic Accuracy

-

69.8%

Cohen's Kappa

-

0.3769

Out of the 71culture proven UTI, 26 had nitrite positivity also with dipstick, giving rise to the Sensitivity of 36.62 %. All the 78 children who found to have no growth in urine were negative for nitrites by dip stick as well, leading to 100% Specificity. All the 26 children who showed nitrites in the urine were culture positive too and hence the positive predictive value is 100 % and among 123 children negative for urinary nitrites by dip stick, 78 children did not grow any organism in urine giving rise to the negative predictive value of 69.8 %  

Diagnostic Characteristics of urinary leucocytes as detected by dip stick vs urine culture:

Sensitivity

-

91.55 %

Specificity

-

84.62 %

Positive Predictive Value

-

84.42 %

Negative Predictive Value

-

91.67 %

Diagnostic Accuracy

-

87.92 %

Cohen's Kappa

-

0.7588

Out of the 71culture proven UTI, 65 had leucocytes positivity also with dip stick, giving rise to the sensitivity of 91.55 %. Regarding urine culture negative 78 children 66 found to have no growth in urine were negative for leucocytes by dip stick as well leading to 84.62% Specificity. Out of 77positive for urine dip stick leucocytes positive cases, 65 children who showed leucocytes in the urine were culture positive too and hence the positive predictive value is 84.42% and the negative predictive value is 91.67 %, as out of the 72 children negative for leucocytes by dip stick 66 children did not grow any organism in urine 

Diagnostic Characteristics of urinary nitrites / leucocytes as detected by dip stick vs urine culture :

Sensitivity

-

91.55 %

Specificity

-

84.62 %

Positive Predictive Value

-

84.42 %

Negative Predictive Value

-

91.67 %

Diagnostic Accuracy

-

87.92 %

Cohen's kappa

-

0.7588

Out of the 71culture proven UTI, 65 had Nitrites or Leucocytes positivity also with dip stick, giving rise to the sensitivity of 91.55 %. Among 78 children with no growth in urine, 66 found to be negative for Nitrites or Leucocytes by dip stick as well, leading to Specificity of 84.62%. Out of 77positive for urine dip stick Nitrites or Leucocytes positive cases, 65 children showed Nitrites or Leucocytes in the urine and hence the positive predictive value is 84.42% and the negative predictive value is 91.67 %, as out of the 72 children negative for Nitrites or Leucocytes by dip stick 66 children did not grow any organism in urine

Conclusions:

Urine dipstick analysis should be integrated into routine clinical practice for the screening of urinary tract infections (UTIs) in children aged 1 month to 36 months. Healthcare providers should prioritize the use of dipsticks as a frontline tool for rapid and non-invasive UTI screening in outpatient settings.

Healthcare professionals should undergo educational initiatives focusing on the nuances of dipstick analysis, its interpretation, and its integration into the broader clinical context. Training programs and workshops can enhance healthcare professionals' confidence in utilizing dipsticks effectively for UTI screening in young children.

Healthcare facilities should implement mechanisms for continuous monitoring and evaluation of urine dipstick utilization and its impact on pediatric UTI diagnosis and management. Regular audits can identify areas for improvement and ensure adherence to best practices.

Public awareness campaigns targeting parents and caregivers are essential to highlight the importance of urine dipstick analysis as a rapid and non-invasive method for UTI screening in young children. Educating caregivers about the significance of early detection through dipstick analysis can facilitate timely intervention and management of UTIs in pediatric populations.

Emphasize the importance of clinical correlation alongside dipstick results. A thorough clinical assessment should complement dipstick analysis to enhance diagnostic accuracy and guide appropriate management decisions for pediatric UTIs.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.