1
|
Zhang G, Dai Z, Yao Y, Yu X, Gao Y, Liang XM, Chen M. Analysis of factors with low positive predictive value in the diagnosis of urinary tract infection by flow cytometry. World J Urol 2023; 41:3611-3618. [PMID: 37898576 DOI: 10.1007/s00345-023-04676-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 10/03/2023] [Indexed: 10/30/2023] Open
Abstract
PURPOSE Culture-negative urine specimens can be rapidly screened by urine flow cytometry (UFC), while low positive predictive value (PPV) limits the clinical application. We explored the factors associated with a low PPV. METHODS A total of 5095 urine specimens were analyzed with UFC and culture. Diagnostic performance of leukocytes, bacteria, and BACT-info flags was evaluated by sensitivity, specificity, PPV, and negative predictive value (NPV). The association of contaminated culture and squamous epithelial cell count and BACT-info flag was performed by logistic regression analysis. RESULTS The NPVs of parallel combination of bacteria and leucocytes were 98.9% in males and 97.9% in females, and PPVs of serial combination were 86.6% and 77.8% in men and women, respectively. The PPV of Gram-negative flag was higher than that of Gram-positive flag. The proportions of contamination in the urine culture results of false positive specimens were 86.9% in males and 98.5% in females at the cutoff points of the serial combination, and these parameters were 53.2% in males and 85.6% in females for the Gram-positive flag. There was a statistically significant association between contaminated cultures and squamous epithelial cells count in females, but not in males. Associations between contaminated cultures and Gram-positive flags or Gram-pos/-neg flags were statistically significant, but there was no association between contaminated cultures and Gram-negative flags. CONCLUSIONS A serial combination of leukocytes and bacteria may maximize PPV in the diagnosis of bacterial urinary tract infection by urine flow cytometry, and contamination is the main reason for a low PPV.
Collapse
Affiliation(s)
- Guoqiang Zhang
- Center of Clinical Laboratory, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361004, China
- Institute of Infectious Disease, School of Medicine, Xiamen University, Xiamen, 361004, China
| | - Zhang Dai
- Center of Clinical Laboratory, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361004, China
- Institute of Infectious Disease, School of Medicine, Xiamen University, Xiamen, 361004, China
| | - Yihui Yao
- Center of Clinical Laboratory, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361004, China
| | - Xiaolu Yu
- Center of Clinical Laboratory, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361004, China
| | - Ying Gao
- Center of Clinical Laboratory, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361004, China
| | - Xian-Ming Liang
- Center of Clinical Laboratory, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361004, China.
- Institute of Infectious Disease, School of Medicine, Xiamen University, Xiamen, 361004, China.
| | - Meijun Chen
- Center of Clinical Laboratory, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361004, China.
| |
Collapse
|
2
|
Oyaert M, Maghari S, Speeckaert M, Delanghe J. Improving clinical performance of urine sediment analysis by implementation of intelligent verification criteria. Clin Chem Lab Med 2022; 60:1772-1779. [PMID: 36069776 DOI: 10.1515/cclm-2022-0617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 08/28/2022] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Urinary test strip and sediment analysis integrated with intelligent verification criteria can help to select samples that need manual review. This study aimed to evaluate the improvement in the diagnostic performance of combined urinary test strip and urinary sediment analysis using intelligent verification criteria on the latest generation automated test strip and urinary fluoresce flow cytometry (UFFC) analysers. METHODS Urine test strip and sediment analysis were performed using the Sysmex UC-3500 and UF-5000 (Kobe, Japan) on 828 urinary samples at the clinical laboratory of the Ghent University Hospital. The results were compared to manual microscopy using phase-contrast microscopy as a reference. After the application of the intelligent verification criteria, we determined whether the diagnostic performance of urine sediment analysis could be improved. RESULTS Application of intelligent verification criteria resulted in an increase in specificity from 88.5 to 96.8% and from 88.2 to 94.9% for red blood cells and white blood cells, respectively. Implementing review rules for renal tubular epithelial cells and pathological casts increased the specificity from 66.7 to 74.2% and from 96.2 to 100.0%, respectively; and improved the diagnostic performance of urinary crystals and atypical cells. CONCLUSIONS The implementation of review rules improved the diagnostic performance of UFFC, thereby increasing the reliability and quality of urine sediment results.
Collapse
Affiliation(s)
- Matthijs Oyaert
- Department of Laboratory Medicine, Ghent University Hospital, Ghent, Belgium
| | - Sena Maghari
- Department of Laboratory Medicine, Ghent University Hospital, Ghent, Belgium
| | - Marijn Speeckaert
- Department of Nephrology, Ghent University Hospital, Ghent, Belgium
- Research Foundation Flanders, Brussels, Belgium
| | - Joris Delanghe
- Department of Laboratory Medicine, Ghent University Hospital, Ghent, Belgium
- Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| |
Collapse
|
3
|
Hall J, Hawkins O, Montgomery A, Singh S, Mullan J, Degeling C. Dismantling antibiotic infrastructures in residential aged care: The invisible work of antimicrobial stewardship (AMS). Soc Sci Med 2022; 305:115094. [PMID: 35690033 DOI: 10.1016/j.socscimed.2022.115094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 05/25/2022] [Accepted: 05/27/2022] [Indexed: 10/18/2022]
Abstract
Recent social science scholarship has sought to understand the visible and invisible impacts of how antibiotics are entrenched as infrastructures and put to work as a proxy for higher levels of care (clinical or otherwise) within modern healthcare. Using a qualitative research design, in this paper our aim is to draw attention to less visible aspects of antimicrobial stewardship (AMS) in residential aged care and their implications for nurse-led optimization of antibiotic use in these settings. By developing an account of the perceptions, experiences and practices of staff regarding the 'on the ground' work associated with implementing and upholding AMS objectives our study extends research on attempts to dismantle antibiotic infrastructures in Australian residential aged care facilities (RACF). Drawing on a review of relevant policies, empirical data is presented from fifty-six in-depth interviews conducted in 2021 with staff at 8 different RACFs. Interview participants included managers, nurses, and senior and junior personal care assistants. Our results suggest that registered nurses in residential aged care have been tasked with promoting antibiotic optimization and assigned with AMS responsibilities without sufficient authority and resourcing. A host of hidden care work associated with AMS strategies was evident, reinforcing some staff support for empirical antibiotic prescribing as a 'safety net' in uncertain clinical cases. We argue that this hidden work occurs where AMS strategies displace the infrastructural role previously performed by antibiotics, exposing structural gaps and pressures. The inability of organisational accounting systems and the broader AMS policy agenda to capture hidden AMS workflows in RACFs has consequences for future resourcing and organisational learning in ways that mean AMS gaps may remain unaddressed. These results support findings that AMS interventions might not be easily accepted by aged care staff in view of associated burdens which are under recognised and under supported in this domain.
Collapse
Affiliation(s)
- Julie Hall
- Australian Centre for Health Engagement, Evidence and Values, The Faculty of Arts, Social Sciences and Humanities, University of Wollongong, NSW, Australia
| | - Olivia Hawkins
- Australian Centre for Health Engagement, Evidence and Values, The Faculty of Arts, Social Sciences and Humanities, University of Wollongong, NSW, Australia
| | - Amy Montgomery
- School of Nursing, Faculty of Science, Medicine and Health, University of Wollongong, NSW, Australia
| | - Saniya Singh
- Australian Centre for Health Engagement, Evidence and Values, The Faculty of Arts, Social Sciences and Humanities, University of Wollongong, NSW, Australia; School of Psychology, University of Wollongong, NSW, Australia
| | - Judy Mullan
- School of Medicine, Faculty of Science, Medicine and Health, University of Wollongong, NSW, Australia; Centre for Health Research Illawarra Shoalhaven Population, Faculty of Science, Medicine and Health, University of Wollongong, NSW, Australia
| | - Chris Degeling
- Australian Centre for Health Engagement, Evidence and Values, The Faculty of Arts, Social Sciences and Humanities, University of Wollongong, NSW, Australia.
| |
Collapse
|
4
|
Novel urine biomarkers to distinguish UTI from culture-negative pyuria. Pediatr Nephrol 2022; 37:385-391. [PMID: 34272611 DOI: 10.1007/s00467-021-05202-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 06/09/2021] [Accepted: 06/10/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Emergency departments (EDs) often rely on urinalysis (UA) to rapidly identify urinary tract infections (UTIs) in children. However, the suboptimal test characteristics of UA can lead to false-positive results. Novel urinary biomarkers may increase the diagnostic precision of UA. In this study, we compared the concentrations of 6 pre-selected proteins: BH3 interacting domain death agonist (BID), B-cell lymphoma 6 protein, ras GTPase-activating protein 1, cathepsin S (CTSS), 3-hydroxyanthranilate 3,4-dioxygenase, and transgelin-2. METHODS In a pediatric ED, we prospectively enrolled 167 children with UA and urine culture collected. Pyuria was defined as either ≥ 5 white blood cells per high-power field on microscopy or positive leukocyte esterase (LE). The urine culture was considered positive if it yielded ≥ 50,000 colony-forming units per milliliter of any single urinary pathogen. Urine protein levels were measured by enzyme-linked immunosorbent assay and normalized to urine creatinine. RESULTS BID was significantly higher in the UTI group compared to the culture-negative pyuria group with a mean ratio of 1.42 (95% confidence interval (CI), 1.15, 1.76) when uncorrected for creatinine concentration. When corrected for creatinine concentration, CTSS was significantly elevated in the UTI group compared to the culture-negative pyuria group with a mean ratio of 2.11 (95% CI, 1.39, 3.21). CONCLUSIONS BID and CTSS concentrations were elevated in the urine of children with UTI compared to those with culture-negative pyuria. These proteins deserve further research into their utility to serve as novel biomarkers for UTI.
Collapse
|