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Intrarenal Injection of Escherichia coli in a Rat Model of Pyelonephritis
Published on: July 18, 2017
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Correlation of Pyuria and Bacteriuria in Acute Care.
Bo Cheng1, Mufrad Zaman1, William Cox1
1LewisGale Hospital Montgomery, Blacksburg, Va.
The American Journal of Medicine
|May 17, 2022
Summary
Pyuria alone is insufficient for diagnosing urinary tract infections. A urine white blood cell count over 25 cells/hpf is the optimal threshold for detecting bacteriuria, guiding clinical decisions.
Area of Science:
- Urology
- Infectious Diseases
- Clinical Diagnostics
Background:
- Pyuria is a common marker for urinary tract infections (UTIs), particularly in patients with vague symptoms.
- Limited data exists on the diagnostic value of pyuria alone for bacteriuria or UTIs.
- This study investigates the correlation between pyuria and bacterial growth in urine cultures.
Purpose of the Study:
- To define the relationship between pyuria and positive urine culture results.
- To evaluate the diagnostic utility of various white blood cell (WBC) count cutoffs in urine microscopy.
- To determine the optimal WBC threshold for predicting bacteriuria.
Main Methods:
- Analysis of 46,127 inpatient urine samples from HCA Healthcare System.
- Stratification of urine microscopy results by WBC count.
- Correlation of WBC counts with bacterial growth in urine cultures.
- Receiver operating characteristic (ROC) curve analysis to determine the optimal WBC cutoff.
Main Results:
- Bacteriuria rates increased with higher WBC counts: 25.4% (0-5 cells/hpf), 28.2% (5-10 cells/hpf), 33% (10-25 cells/hpf), and 53.8% (>25 cells/hpf).
- Pyuria alone demonstrated inadequate diagnostic accuracy for predicting bacteriuria.
- The optimal WBC cutoff for bacteriuria detection was identified as 25 cells/hpf.
Conclusions:
- Pyuria alone is not a reliable diagnostic indicator for bacteriuria.
- A urine WBC count exceeding 25 cells/hpf is the optimal cutoff for detecting bacteriuria.
- Findings support current guidelines against antibiotic treatment based solely on urinalysis and inform future research on managing patients with pyuria and nonspecific complaints.
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