title: Clinical validation of integrated nucleic acid and protein detection on an electrochemical biosensor array for urinary tract infection diagnosis.
abstract: BACKGROUND
  Urinary tract infection (UTI) is a common infection that poses a substantial healthcare burden, yet its definitive diagnosis can be challenging. There is a need for a rapid, sensitive and reliable analytical method that could allow early detection of UTI and reduce unnecessary antibiotics. Pathogen identification along with quantitative detection of lactoferrin, a measure of pyuria, may provide useful information towards the overall diagnosis of UTI. Here, we report an integrated biosensor platform capable of simultaneous pathogen identification and detection of urinary biomarker that could aid the effectiveness of the treatment and clinical management.
  
  
  RESULTS
  The integrated pathogen 16S rRNA and host lactoferrin detection using the biosensor array was performed on 113 clinical urine samples collected from patients at risk for complicated UTI. For pathogen detection, the biosensor used sandwich hybridization of capture and detector oligonucleotides to the target analyte, bacterial 16S rRNA. For detection of the protein biomarker, the biosensor used an analogous electrochemical sandwich assay based on capture and detector antibodies. For this assay, a set of oligonucleotide probes optimized for hybridization at 37°C to facilitate integration with the immunoassay was developed. This probe set targeted common uropathogens including E. coli, P. mirabilis, P. aeruginosa and Enterococcus spp. as well as less common uropathogens including Serratia, Providencia, Morganella and Staphylococcus spp. The biosensor assay for pathogen detection had a specificity of 97% and a sensitivity of 89%. A significant correlation was found between LTF concentration measured by the biosensor and WBC and leukocyte esterase (p<0.001 for both).
  
  
  CONCLUSIONS
  We successfully demonstrate simultaneous detection of nucleic acid and host immune marker on a single biosensor array in clinical samples. This platform can be used for multiplexed detection of nucleic acid and protein as the next generation of urinary tract infection diagnostics.
authors: Department of Urology and Bio-X Program, Stanford University School of Medicine, Stanford, California, United States of America.
authors: Ruchika
authors: R
authors: Mohan
authors: Kathleen E
authors: KE
authors: Mach
authors: Moran
authors: M
authors: Bercovici
authors: Ying
authors: Y
authors: Pan
authors: Lakshmi
authors: L
authors: Dhulipala
authors: Pak Kin
authors: PK
authors: Wong
authors: Joseph C
authors: JC
authors: Liao
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D055664:Electrochemical Techniques / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D007781:Lactoferrin / Q000652:urine; D009693:Nucleic Acid Hybridization; D009696:Nucleic Acids / Q000652:urine*; D015345:Oligonucleotide Probes / Q000378:metabolism; D011506:Proteins / Q000032:analysis*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012680:Sensitivity and Specificity; D013696:Temperature; D014552:Urinary Tract Infections / Q000175:diagnosis* / Q000652:urine*
chemical_list: D009696:Nucleic Acids; D015345:Oligonucleotide Probes; D011506:Proteins; D012336:RNA, Ribosomal, 16S; D007781:Lactoferrin