Table Three : Positive and Negative Predictive Values of Urine Dipstick and Microscopic Urinalysis With Corresponding Overtreatment and Undertreatment Rates
Testing Modality |
PPV (%) |
NPV (%) |
Overtreatment |
|
|
|
Rate (%) |
Urine Dipstick
Undertreatment Rate (%)
LE or N or blood 51 94 49 6 LE < 2 and N 88 52 13 48
Microscopic Urinalysis RBC or WBC 50 93 50 7 RBC > 50 or WBC > 10 64 74 37 25
Abbreviations : LE , leukocyte esterase ; N , nitrate ; NPV , negative predictive value ; PPV , positive predictive value ; RBC , red blood cell ; WBC , white blood cell .
Table Four : Sensitivity , Specificity , and Likelihood Ratio for Urine Dipstick and Microscopic Urinalysis
Testing Modality |
Sensitivity (%) |
Specificity (%) |
Positive LR (%) |
Negative LR (%) |
|
|
Urine Dipstick |
|
|
LE |
75 - 91 |
41 - 87 |
1.59 - 5.6 |
0.2 - 0.4 |
N |
34 - 42 |
94 - 98 |
7.5 - 24.6 |
0.6 - 0.7 |
Blood |
92 |
42 |
2.6 |
0.2 |
Protein |
83 |
44 |
2.1 |
0.3 |
LE + N |
30 - 38 |
91 - 100 |
3.4 to infinity |
0.6 - 0.8 |
LE or N |
91 - 92 |
39 - 41 |
1.5 - 1.6 |
0.2 |
|
|
Microscopic Urinalysis |
|
|
WBC Men > 5 Women > 10
57 - 90 47 - 89 1.7 - 5.0 0.2 - 0.5
Bacteria > 0 9 - 83 59 - 72 2.3 - 2.9 0.1 - 0.5 RBC > 5 59 - 63 67 - 74 1.6 0 WBC or bacteria 100 39 1.6 0 WBC and bacteria 58 81 3 0.5
Abbreviations : LE , leukocyte esterase ; LR , likelihood ratio ; N , nitrate ; NPV , negative predictive value ; PPV , positive predictive value ; RBC , red blood cell ; WBC , white blood cell .
References
1 . National Guideline Clearinghouse . Management of suspected bacterial urinary tract infection in adults . 2006 . Retrieved from : guideline . gov . 2 . Scottish Intercollegiate Guidelines Network . Management of suspected bacterial urinary tract infection in adults . 2012 . Retrieved from : sign . ac . uk . 3 . Diagnosis and treatment of acute uncomplicated cystitis . 2011 . Downloaded from the American Family Physician Web site at : 111 . aafp . org / afp . 4 . Up-to-Date . Urinary tract infections and asymptomatic bacteriuria in pregnancy . 2016 . 5 . Up-to-Date . Acute complicated cystitis and pyelonephritis . 2016 . 6 . Up-to-Date . Acute uncomplicated cystitis , pyelonephritis , and symptomatic bacteriuria in men . 2016 . 7 . Up-to-Date . Acute uncomplicated cystitis and pyelonephritis in women . 2016 .
This clinical guideline outlines the recommendations of Mount Carmel Health Partners for this medical condition and is based upon the referenced best practices . It is not intended to serve as a substitute for professional medical judgment in the diagnosis and treatment of a particular patient . Decisions regarding care are subject to individual consideration and should be made by the patient and treating physician in concert .
Original Issue Date : November 2011 Revision Dates : July 2015 , October 2015 , July 2017
UTI - 6