A novel home-use culture mechanism for identifying microbial load in urine samples

A novel home-use culture mechanism for identifying microbial load in urine samples | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article A novel home-use culture mechanism for identifying microbial load in urine samples Siddharth Pattnaik, Monika Singh, Riya Sahai This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2247512/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Diagnosing a urinary tract infection (UTI) is typically a clinical procedure involving multiple steps. The need to perform a test depends on the presence of relevant symptoms. Given the current pandemic situation, visiting a clinic may not be a preferable choice for many users. Many vulnerable groups of patients, namely, males with certain predispositions and pregnant women, may not present with symptoms of UTI, which could give rise to a more complicated situation. Microbial culture provides a definitive diagnosis for the presence of an infection. A home-use culture kit can serve this purpose; however, to our knowledge, no such kit exists. Here, we present a feasibility study of an affordable and easy-to-use home-based setup for quantifying bacterial load in a urine. Teaser A home-use system for monitoring progression and management of UTIs. General Microbiology Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Microbial cell culture is a versatile tool widely used to detect, identify, and quantify pathogenic loads for research and diagnostic purposes. Inoculating clinical specimens into a pathogen-specific culture media aids the visualisation of these pathogens to assess the microbial origin and severity of the disease. Standard culture-based diagnostic methods can detect microbes in urine samples, stools, the genital tract, deep throat, and skin. An example of microbial infection is urinary tract infection, which affects the ureters, urethra, urinary bladder, or, in extreme cases, kidneys. UTIs are classified as uncomplicated or complicated, comprising multiple disorders such as asymptomatic bacteriuria (ASB), acute uncomplicated cystitis, recurrent cystitis, catheter-associated ASB, catheter-associated UTI (CAUTI), prostatitis, and pyelonephritis. Several risk factors are associated with uncomplicated UTIs, including sex bias, prior UTI exposure, sexual activity, vaginal infection, diabetes, obesity, and genetic susceptibility ( 1 ). UTI is acquired by up to 50–60% of individuals at least once in their lifetime ( 2 ). Thus, individuals at risk need to undergo regular screening to avoid further complications or progression to complicated UTIs. Currently, the most common method of diagnosing UTI is urinalysis, which includes chemical, physical, and microscopic analyses of urine samples ( 3 ). Predictive urinalysis is used most commonly to decide the treatment for uncomplicated UTIs. However, these tests provide inaccurate results nearly 33% of the time, and their sensitivity ranges from 23–95.6%, depending on the type of patient ( 4 – 6 ). A significant limitation of this method is its inability to determine the causative agent, which may lead to the prescription of an incorrect treatment strategy that aggravates the development of multidrug-resistant bacterial species, further increasing the burden of antimicrobial resistance ( 7 ). Urine cultures, in contrast, help identify the exact causative agent. Since UTI symptoms also coincide with the early symptoms of many sexually transmitted diseases and vaginal infections, urine cultures are necessary to differentiate UTIs from other related disorders ( 8 ). For these reasons, urine culture is considered the ‘gold standard’ for diagnosing UTIs ( 9 , 10 ). Traditionally, urine culture is conducted by applying the sample to plates containing the relevant media. The pathogens form colonies visible to the naked eye and the number of colonies helps to determine the microbial load in the sample. However, this method requires skilled technicians and considerable time for results to reach the patient. The commercial products available, namely, dip-slides ( 11 ), incompletely tackle this problem since the samples need to be shipped back to the laboratory for colony counting and pathogen identification. In addition, these tests are designed for a midstream sample and hence require volumes in the range of 50–60 mL. This study presents a novel home-based method for culturing and detecting microbes. Our primary goal was to design a system derived from the dipstick format and integrate it with a culture medium, which can also be extended to other cultures and infections. In this study, we focused on microbes causing UTIs, specifically Escherichia Coli to demonstrate the dynamic nature of this system regarding microbes and culture media. Results Microbial growth is unaffected by the location of the culture application Since the design of our system was dependent on the delivery of the sample from the bottom to avoid any contamination from air or external sources, we aimed to prove that culturing bacteria below an agar medium can be used to estimate the bacterial load. In addition, we checked whether sensitivity was maintained in terms of colony density between the two methods. To achieve this, we diluted the cultured bacterial media and compared the top streaking method with the bottom application. The bottom application was performed in two ways: by streaking and pouring the culture media. In both cases, agar was placed after the culture was applied to the plate (Fig. 1 a). Illustration of experimental design to generate serial dilutions and of different application methods (a). Schematic of the imaging set up used for capturing images of the cultured plates using a mobile phone (b). We streaked the culture on top of the Luria Bertani (LB) agar plates as a control to ascertain that there was no contamination. For the initial run, MacConkey agar plates were used because they are commonly used to diagnose UTIs ( 12 ). Interestingly, we found that the dilutions were visibly distinct from one another in all different setups (Fig. 2 a). For quantification, we selected dilutions where distinct colonies could be counted: 1:10 5 , 1:10 6 , and 1:10 9 . Interestingly, we found that the number of colonies was also similar in all methods of sample application (Fig. 2 b), indicating that culture grown below an agar medium has similar sensitivity and performance as the canonical culture application. In addition, manual counting and OpenCFU-based quantification yielded similar results (Fig. 2 b). Growth of cultured E.coli on MacConkey agar applied using various methods i.e. top streak, bottom streak and bottom drop and over serial dilutions (a). Comparison of CFU/ml obtained from different application methods and using different quantification methods. CFU/ml was significantly different (p 0.1). We then examined whether our observations were media-specific. To assess this, we chose HiChrome chromogenic agar media, a commonly used growth medium for diagnosing the causative agent of UTI. The experimental setup for this growth medium was similar to that shown in Fig. 1 a. With the chromogenic agar media, we replicated the observations with MacConkey agar (Supplementary Fig. 1a and 1b), indicating that the bottom culture application method is also true for different types of agar media. Membrane-mediated Bottom Delivery Performs Similar To Direct Application In a home-use setup, pipetting a fixed volume of liquid onto or below the agar medium is usually not feasible. Therefore, we investigated whether a membrane-mediated delivery could solve this issue. For this purpose, we developed the system shown in Fig. 3 a, where the membrane jutting out of the Petri dish was used to deliver the sample to the agar media. The protruding end of the membrane was dipped in bacteria-containing media for 15 s. We examined the setup using different agar media to establish the robustness of this method. Similar culture dilutions were used in the previous experiments. We observed a visible gradient in the colony count for each dilution in all the different agar media used (Fig. 3 b, Supplementary Fig. 2a). Schematic of the membrane-based delivery apparatus (a). Growth of cultured E.coli on MacConkey agar at 37℃ for 16 hours and at 25℃ for 30 hours with the sample delivered using the membrane (b). Comparison of CFU obtained manually for both temperature conditions. CFU was significantly different (p < 0.1) between all dilutions in which colonies could be counted for both the conditions except between 1:10 5 and 1:10 6 at 25℃ (p = 0.5). CFU calculated for both conditions were not significantly different in any dilution (p > 0.1). Since in this setup the native culture, 1:10 3 , and 1:10 5 dilutions developed dense colonies, we could not consider these concentrations for further quantification. The computed number of colonies was greater than in the previous experimental designs discussed since a greater culture volume was being delivered to the sample pad. Hence, we demonstrated that membrane-mediated sample delivery works equally well with the top or bottom application of the culture without affecting the sensitivity of the entire system. Membrane-delivered Microbial Samples Can Be Cultured At Room Temperature To facilitate the use of the system at home, cultures needed to be grown at room temperature. Therefore, we investigated the performance of the membrane-based delivery mechanism at room temperature. The aim was to determine the earliest time point at which distinct colonies were visible. We found that colonies were visible within 36 h of the sample application. Interestingly, we discovered that at 36 h, the colonies obtained were similar in number to those cultured at 37°C for 16 h, indicating that 36 h is probably long enough for any bacterial load to manifest. However, we found that at lower temperatures, the difference between dilutions 1:10 5 and 1:10 6 (although existent) was not as statistically significant as the difference obtained by growing the culture at 37°C. This could imply that this system is slightly less sensitive than growth at higher temperatures and may have to be tweaked accordingly. It is also possible that a larger number of replicates may overcome this variation. Discussion In this study, we present a novel system to visualise and quantify the bacterial load in urine samples at home to detect and identify UTI-related pathogens. To the best of our knowledge, such a system does not exist for the diagnosis and management of UTIs. While this system presented consistent results in spiked urine and cultured bacteria, it needs to be validated with clinical samples, which will be the scope of a future study. Our results indicated that the sensitivity of the assay varied slightly when cultured at different temperatures. This variation should be considered when establishing clinical relevance. Another issue that needs to be addressed is the hygienic disposal of culture plates in home-use scenarios. However, this can be solved operationally by providing a bag for safe disposal or a tube of bleach that can be applied once the results have been secured. We foresee many potential applications for such home-use systems. For instance, certain groups of patients who are more vulnerable to UTI or are at risk of asymptomatic UTI can keep these at home and monitor the presence or absence of infection regularly. In the case of an infection, the results can be shared with the respective physician. As an extension, the results from this system can be used by physicians to remotely identify the causative agent, assess the microbial load, and suggest the most effective treatment (Fig. 4 ). A representative flow chart of the interaction between the user and the physician with the membrane-based delivery system aiding the diagnosis and intervention process. Antibiotic resistance in uropathogens has been widely studied and is a concern ( 13 – 15 ). Since our system can help in identifying the exact species that cause infection, it can be used to prescribe species-specific antibiotics. This would help reduce the burden of antibiotic resistance, preventing the development of multidrug-resistant pathogens, which would be especially useful in patients with recurrent UTIs. As a primary goal, we have also demonstrated that bottom culture is feasible and the number of colonies formed is comparable to that of a standard top streak. Recently, many tests have been based on analysing dried urine samples, where the samples can be transported on a filter card ( 16 ). One of our future aims is to study the efficacy of this system with dried urine samples on a filter card. A comparative analysis of the microbial load in liquid and dried urine samples may be worthwhile to make this system more beneficial. Future studies will also focus on a mobile application-based system that can be used to quantify the microbial load and determine the severity of infections. Materials And Methods Bacterial Cell Culture The E. coli strain K-12 was used in this study. A single colony was inoculated to obtain uniform growth. To isolate pink colonies, 10 µL of the culture was spread on a MacConkey agar plate. For all experiments, pink colonies were selected from the plate and grown in a 600 mL Luria Bertani (LB) medium. The cultures were incubated in a shaker incubator maintained at 37°C with rotation at 180 rpm. The culture was monitored every 2 h until an optical density (OD) of approximately 0.65–0.75 was achieved. Optical density was measured in triplicates. To compare the OD values, sterile blank LB solution was incubated under similar conditions. This was used as blank for all measurements. For all experiments, a blank plate and a plate with the blank solution were incubated along with the different experimental setups to ensure the sterility of the incubator and culture media. Culture Media Preparation For all experiments with E. Coli , three different agar media were used: Luria Bertani (LB) agar (M1151, HiMedia, USA), MacConkey agar (M7408, Millipore, USA), and HiChrome Agar (M1353R, HiMedia, USA). For preparing the LB agar. For the preparation of MacConkey Agar, 30 gm of the agar was mixed with 600 mL distilled water. For the preparation of HiChrome Agar, 34.08 gm was mixed in 600 mL distilled water. All the agar media and liquid cultures were autoclaved at 121°C and 15 psi for 30 min. Membrane Selection For all experiments with membranes, Whatman Grade 470 was used to deliver the sample to agar media. This was selected based on the pore size of the membrane. Before integrating the membrane into the experiment it was washed thoroughly with 70% ethanol, followed by washing with distilled water. Image Capturing And Analysis All cultured plates were imaged using an in-built phone camera. A customised LED-mounted translucent light diffuser setup (designed for home use) was used to capture images of the cultured plates (Fig. 1 b). Images were captured using iPhone 12. The images were captured at an exposure of 1/875s and ISO 32. Colonies were counted manually using OpenCFU to establish if the system could be quantified using available software as well. No post-capture changes were applied to the images before processing with OpenCFUs. Statistical analysis All statistical analyses were performed using GraphPad Prism version 9. For all groups of experiments, an unpaired, non-parametric t-test (Kolmogorov–Smirnov test) was performed to compare the cumulative distributions and determine the p-value. Results were considered statistically significant at a p-value of 0.1 and a 90% statistical significance. References 1. O. Storme, J. Tirán Saucedo, A. Garcia-Mora, M. Dehesa-Dávila, K. G. Naber, Risk factors and predisposing conditions for urinary tract infection. Ther. Adv. Urol. 11 , 1756287218814382 (2019). 2. A. Al-Badr, G. Al-Shaikh, Recurrent Urinary Tract Infections Management in Women: A review. Sultan Qaboos Univ. Med. J. 13 , 359–367 (2013). 3. D. A. Queremel Milani, I. Jialal, Urinalysis, in StatPearls (StatPearls Publishing, 2022). 4. G. Schmiemann, E. Kniehl, K. Gebhardt, M. M. Matejczyk, E. Hummers-Pradier, The diagnosis of urinary tract infection: A systematic review. Dtsch. Ärztebl. Dtsch. Arztebl. Int. 107 , 361–367 (2010). 5. D. C. A. Feitosa, M. G. da Silva, C. M. G. de Lima Parada, Accuracy of simple urine tests for diagnosis of urinary tract infections in low-risk pregnant women. Rev. Lat. Am Enfermagem. 17 , 507–513 (2009). 6. A. K. Mambatta, J. Jayarajan, V. L. Rashme, S. Harini, S. Menon, J. Kuppusamy, Reliability of dipstick assay in predicting urinary tract infection. J. Fam ily Med. Prim. Care. 4 , 265–268 (2015). 7. A. L. Flores-Mireles, J. N. Walker, M. Caparon, S. J. Hultgren, Urinary tract infections: Epidemiology, mechanisms of infection and treatment options. Nat. Rev. Microbiol. 13 , 269–284 (2015). 8. K. Gupta, L. Grigoryan, B. Trautner, Urinary tract infection. Ann. Intern. Med. , ITC49 . 167 , ITC49–ITC64 (2017). 9. C. Carter, J. Stallworth, R. Holleman Chapter 40, Urinary tract disorders, in Textbook of Family Medicine, ed. 8, R. E. Rakel, D. P. Rakel, Eds. (W. B. Saunders, 2012), pp. 899–927. doi:10.1016/B978-1-4377-1160-8.10040-5. 10. H. Sinawe, D. Casadesus, Urine culture, in StatPearls (StatPearls Publishing, 2022). 11. G. R. Naylor, D. Guttmann, The dip-slide: A modified dip-inoculum transport medium for the laboratory diagnosis of infections of the urinary tract. J. Hyg. (Lond). 65 , 367–371 (1967). 12. J. C. Fung, B. Lucia, E. Clark, M. Berman, J. Goldstein, R. F. D’Amato, Primary culture media for routine urine processing. J. Clin. Microbiol. 16 , 632–636 (1982). 13. S. S. Ahmed, A. Shariq, A. A. Alsalloom, I. H. Babikir, B. N. Alhomoud, Uropathogens and their antimicrobial resistance patterns: Relationship with urinary tract infections. Int. J. Health Sci. (Qassim) . 13 , 48–55 (2019). 14. R. Paul, State of the globe: Rising antimicrobial resistance of pathogens in urinary tract infection. J. Glob. Infect. Dis. 10 , 117–118 (2018). 15. S. A. R. Mortazavi-Tabatabaei, J. Ghaderkhani, A. Nazari, K. Sayehmiri, F. Sayehmiri, I. Pakzad, Pattern of antibacterial resistance in urinary tract infections: A systematic review and meta-analysis. Int. J. Prev. Med. 10 , 169 (2019). 16. M. Newman, D. A. Curran, Reliability of a dried urine test for comprehensive assessment of urine hormones and metabolites. BMC Chem. 15 , 18 (2021). Additional Declarations The authors declare no competing interest. 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Also discoverable on Platform About Our Team In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-2247512","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":150160500,"identity":"f86a49aa-907e-4a2f-afcb-c1d72c0e414a","order_by":0,"name":"Siddharth Pattnaik","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxUlEQVRIiWNgGAWjYDACZgYDaRBtwN7YwJBAihYJA56DQC3E6YFpkQApJ0aLfDvzxtsFNffqzCUftz14+MOGgb+9G79Gg8NsxdYzjhVLWM5ObDdISEhjkDhzdgN+Lcw8ZtI8bAkSBrcT2yQSEg4zGEjk4tci3wzS8g+o5eZBIrUwHAZq4W0DarnBSKQWsF94+xIkN5wBOSwtjYegX+T7D2+8zfMtgd/g+PFnkj9sbOT423sJOAwd8JCmfBSMglEwCkYBVgAAGN5BotFND2EAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0003-4136-5180","institution":"Samplytics Technologies Pvt. 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Schematic of the imaging set up used for capturing images of the cultured plates using a mobile phone (b).\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-2247512/v1/9c077bc54965ea3f3e39a345.png"},{"id":28869989,"identity":"22e0b60a-7fa9-4cde-a4df-6348ce4d0740","added_by":"auto","created_at":"2022-11-09 18:37:11","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":566954,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eGrowth of E.coli on MacConkey agar delivered as per experimental design\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eGrowth of cultured E.coli on MacConkey agar applied using various methods i.e. top streak, bottom streak and bottom drop and over serial dilutions (a). Comparison of CFU/ml obtained from different application methods and using different quantification methods. CFU/ml was significantly different (p\u0026lt;0.1) between all dilutions for both the quantification methods as well as for all methods of application. CFU/ml calculated manually and by OpenCFU were not significantly different (p\u0026gt;0.1).\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-2247512/v1/20d601c1aa46c0934deb86fe.png"},{"id":28869352,"identity":"53939604-f72e-40e2-9897-e1854c9e7434","added_by":"auto","created_at":"2022-11-09 18:21:11","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":423730,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMembrane based culture delivery and corresponding growth of E.coli at different temperatures in MacConkey agar\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSchematic of the membrane-based delivery apparatus (a). Growth of cultured E.coli on MacConkey agar at 37℃ for 16 hours and at 25℃ for 30 hours with the sample delivered using the membrane (b). Comparison of CFU obtained manually for both temperature conditions. CFU was significantly different (p\u0026lt;0.1) between all dilutions in which colonies could be counted for both the conditions except between 1:10\u003csup\u003e5\u003c/sup\u003e and 1:10\u003csup\u003e6\u003c/sup\u003e at 25℃ (p=0.5). CFU calculated for both conditions were not significantly different in any dilution (p\u0026gt;0.1).\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-2247512/v1/c5ab9e318ac59c381500d98d.png"},{"id":28869353,"identity":"78a3a6d9-b186-4a80-ba83-7f39692f38ca","added_by":"auto","created_at":"2022-11-09 18:21:14","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":134651,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFlowchart of putative home usage of the membrane-based delivery system\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA representative flow chart of the interaction between the user and the physician with the membrane-based delivery system aiding the diagnosis and intervention process.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-2247512/v1/5a6e8501a18b360bd010d126.png"},{"id":28870012,"identity":"317f3cb9-4e6b-4209-8383-32879af384f4","added_by":"auto","created_at":"2022-11-09 18:37:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1504323,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2247512/v1/137f9fc4-150d-4cd0-9d92-43a1c70e6156.pdf"},{"id":28869349,"identity":"966567c3-d51d-4afb-8a3d-0863cd52d032","added_by":"auto","created_at":"2022-11-09 18:21:11","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":1124386,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementaryinformation.docx","url":"https://assets-eu.researchsquare.com/files/rs-2247512/v1/da5138d227a83a38005cda51.docx"}],"financialInterests":"\u003cp\u003eThe authors declare no competing interest.\u003c/p\u003e","formattedTitle":"\u003cp\u003e\u003cstrong\u003eA novel home-use culture mechanism for identifying microbial load in urine samples\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eMicrobial cell culture is a versatile tool widely used to detect, identify, and quantify pathogenic loads for research and diagnostic purposes. Inoculating clinical specimens into a pathogen-specific culture media aids the visualisation of these pathogens to assess the microbial origin and severity of the disease.\u003c/p\u003e \u003cp\u003eStandard culture-based diagnostic methods can detect microbes in urine samples, stools, the genital tract, deep throat, and skin. An example of microbial infection is urinary tract infection, which affects the ureters, urethra, urinary bladder, or, in extreme cases, kidneys. UTIs are classified as uncomplicated or complicated, comprising multiple disorders such as asymptomatic bacteriuria (ASB), acute uncomplicated cystitis, recurrent cystitis, catheter-associated ASB, catheter-associated UTI (CAUTI), prostatitis, and pyelonephritis. Several risk factors are associated with uncomplicated UTIs, including sex bias, prior UTI exposure, sexual activity, vaginal infection, diabetes, obesity, and genetic susceptibility (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). UTI is acquired by up to 50\u0026ndash;60% of individuals at least once in their lifetime (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Thus, individuals at risk need to undergo regular screening to avoid further complications or progression to complicated UTIs.\u003c/p\u003e \u003cp\u003eCurrently, the most common method of diagnosing UTI is urinalysis, which includes chemical, physical, and microscopic analyses of urine samples (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Predictive urinalysis is used most commonly to decide the treatment for uncomplicated UTIs. However, these tests provide inaccurate results nearly 33% of the time, and their sensitivity ranges from 23\u0026ndash;95.6%, depending on the type of patient (\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). A significant limitation of this method is its inability to determine the causative agent, which may lead to the prescription of an incorrect treatment strategy that aggravates the development of multidrug-resistant bacterial species, further increasing the burden of antimicrobial resistance (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). Urine cultures, in contrast, help identify the exact causative agent. Since UTI symptoms also coincide with the early symptoms of many sexually transmitted diseases and vaginal infections, urine cultures are necessary to differentiate UTIs from other related disorders (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). For these reasons, urine culture is considered the \u0026lsquo;gold standard\u0026rsquo; for diagnosing UTIs (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTraditionally, urine culture is conducted by applying the sample to plates containing the relevant media. The pathogens form colonies visible to the naked eye and the number of colonies helps to determine the microbial load in the sample. However, this method requires skilled technicians and considerable time for results to reach the patient. The commercial products available, namely, dip-slides (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e), incompletely tackle this problem since the samples need to be shipped back to the laboratory for colony counting and pathogen identification. In addition, these tests are designed for a midstream sample and hence require volumes in the range of 50\u0026ndash;60 mL.\u003c/p\u003e \u003cp\u003eThis study presents a novel home-based method for culturing and detecting microbes. Our primary goal was to design a system derived from the dipstick format and integrate it with a culture medium, which can also be extended to other cultures and infections. In this study, we focused on microbes causing UTIs, specifically \u003cem\u003eEscherichia Coli\u003c/em\u003e to demonstrate the dynamic nature of this system regarding microbes and culture media.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eMicrobial growth is unaffected by the location of the culture application\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eSince the design of our system was dependent on the delivery of the sample from the bottom to avoid any contamination from air or external sources, we aimed to prove that culturing bacteria below an agar medium can be used to estimate the bacterial load. In addition, we checked whether sensitivity was maintained in terms of colony density between the two methods. To achieve this, we diluted the cultured bacterial media and compared the top streaking method with the bottom application. The bottom application was performed in two ways: by streaking and pouring the culture media. In both cases, agar was placed after the culture was applied to the plate (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea).\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eIllustration of experimental design to generate serial dilutions and of different application methods (a). Schematic of the imaging set up used for capturing images of the cultured plates using a mobile phone (b).\u003c/p\u003e \u003cp\u003eWe streaked the culture on top of the Luria Bertani (LB) agar plates as a control to ascertain that there was no contamination. For the initial run, MacConkey agar plates were used because they are commonly used to diagnose UTIs (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). Interestingly, we found that the dilutions were visibly distinct from one another in all different setups (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea). For quantification, we selected dilutions where distinct colonies could be counted: 1:10\u003csup\u003e5\u003c/sup\u003e, 1:10\u003csup\u003e6\u003c/sup\u003e, and 1:10\u003csup\u003e9\u003c/sup\u003e. Interestingly, we found that the number of colonies was also similar in all methods of sample application (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb), indicating that culture grown below an agar medium has similar sensitivity and performance as the canonical culture application. In addition, manual counting and OpenCFU-based quantification yielded similar results (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb).\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eGrowth of cultured E.coli on MacConkey agar applied using various methods i.e. top streak, bottom streak and bottom drop and over serial dilutions (a). Comparison of CFU/ml obtained from different application methods and using different quantification methods. CFU/ml was significantly different (p\u0026thinsp;\u0026lt;\u0026thinsp;0.1) between all dilutions for both the quantification methods as well as for all methods of application. CFU/ml calculated manually and by OpenCFU were not significantly different (p\u0026thinsp;\u0026gt;\u0026thinsp;0.1).\u003c/p\u003e \u003cp\u003eWe then examined whether our observations were media-specific. To assess this, we chose HiChrome chromogenic agar media, a commonly used growth medium for diagnosing the causative agent of UTI. The experimental setup for this growth medium was similar to that shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea. With the chromogenic agar media, we replicated the observations with MacConkey agar (Supplementary Fig.\u0026nbsp;1a and 1b), indicating that the bottom culture application method is also true for different types of agar media.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eMembrane-mediated Bottom Delivery Performs Similar To Direct Application\u003c/h3\u003e\n\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eIn a home-use setup, pipetting a fixed volume of liquid onto or below the agar medium is usually not feasible. Therefore, we investigated whether a membrane-mediated delivery could solve this issue. For this purpose, we developed the system shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ea, where the membrane jutting out of the Petri dish was used to deliver the sample to the agar media. The protruding end of the membrane was dipped in bacteria-containing media for 15 s. We examined the setup using different agar media to establish the robustness of this method. Similar culture dilutions were used in the previous experiments. We observed a visible gradient in the colony count for each dilution in all the different agar media used (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb, Supplementary Fig.\u0026nbsp;2a).\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eSchematic of the membrane-based delivery apparatus (a). Growth of cultured E.coli on MacConkey agar at 37℃ for 16 hours and at 25℃ for 30 hours with the sample delivered using the membrane (b). Comparison of CFU obtained manually for both temperature conditions. CFU was significantly different (p\u0026thinsp;\u0026lt;\u0026thinsp;0.1) between all dilutions in which colonies could be counted for both the conditions except between 1:10\u003csup\u003e5\u003c/sup\u003e and 1:10\u003csup\u003e6\u003c/sup\u003e at 25℃ (p\u0026thinsp;=\u0026thinsp;0.5). CFU calculated for both conditions were not significantly different in any dilution (p\u0026thinsp;\u0026gt;\u0026thinsp;0.1).\u003c/p\u003e \u003cp\u003eSince in this setup the native culture, 1:10\u003csup\u003e3\u003c/sup\u003e, and 1:10\u003csup\u003e5\u003c/sup\u003e dilutions developed dense colonies, we could not consider these concentrations for further quantification. The computed number of colonies was greater than in the previous experimental designs discussed since a greater culture volume was being delivered to the sample pad. Hence, we demonstrated that membrane-mediated sample delivery works equally well with the top or bottom application of the culture without affecting the sensitivity of the entire system.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eMembrane-delivered Microbial Samples Can Be Cultured At Room Temperature\u003c/h3\u003e\n\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eTo facilitate the use of the system at home, cultures needed to be grown at room temperature. Therefore, we investigated the performance of the membrane-based delivery mechanism at room temperature. The aim was to determine the earliest time point at which distinct colonies were visible. We found that colonies were visible within 36 h of the sample application. Interestingly, we discovered that at 36 h, the colonies obtained were similar in number to those cultured at 37\u0026deg;C for 16 h, indicating that 36 h is probably long enough for any bacterial load to manifest. However, we found that at lower temperatures, the difference between dilutions 1:10\u003csup\u003e5\u003c/sup\u003e and 1:10\u003csup\u003e6\u003c/sup\u003e (although existent) was not as statistically significant as the difference obtained by growing the culture at 37\u0026deg;C. This could imply that this system is slightly less sensitive than growth at higher temperatures and may have to be tweaked accordingly. It is also possible that a larger number of replicates may overcome this variation.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eIn this study, we present a novel system to visualise and quantify the bacterial load in urine samples at home to detect and identify UTI-related pathogens. To the best of our knowledge, such a system does not exist for the diagnosis and management of UTIs. While this system presented consistent results in spiked urine and cultured bacteria, it needs to be validated with clinical samples, which will be the scope of a future study. Our results indicated that the sensitivity of the assay varied slightly when cultured at different temperatures. This variation should be considered when establishing clinical relevance. Another issue that needs to be addressed is the hygienic disposal of culture plates in home-use scenarios. However, this can be solved operationally by providing a bag for safe disposal or a tube of bleach that can be applied once the results have been secured.\u003c/p\u003e \u003cp\u003eWe foresee many potential applications for such home-use systems. For instance, certain groups of patients who are more vulnerable to UTI or are at risk of asymptomatic UTI can keep these at home and monitor the presence or absence of infection regularly. In the case of an infection, the results can be shared with the respective physician. As an extension, the results from this system can be used by physicians to remotely identify the causative agent, assess the microbial load, and suggest the most effective treatment (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eA representative flow chart of the interaction between the user and the physician with the membrane-based delivery system aiding the diagnosis and intervention process.\u003c/p\u003e \u003cp\u003eAntibiotic resistance in uropathogens has been widely studied and is a concern (\u003cspan additionalcitationids=\"CR14\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). Since our system can help in identifying the exact species that cause infection, it can be used to prescribe species-specific antibiotics. This would help reduce the burden of antibiotic resistance, preventing the development of multidrug-resistant pathogens, which would be especially useful in patients with recurrent UTIs.\u003c/p\u003e \u003cp\u003eAs a primary goal, we have also demonstrated that bottom culture is feasible and the number of colonies formed is comparable to that of a standard top streak. Recently, many tests have been based on analysing dried urine samples, where the samples can be transported on a filter card (\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e). One of our future aims is to study the efficacy of this system with dried urine samples on a filter card. A comparative analysis of the microbial load in liquid and dried urine samples may be worthwhile to make this system more beneficial. Future studies will also focus on a mobile application-based system that can be used to quantify the microbial load and determine the severity of infections.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"Materials And Methods","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eBacterial Cell Culture\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe \u003cem\u003eE. coli\u003c/em\u003e strain K-12 was used in this study. A single colony was inoculated to obtain uniform growth. To isolate pink colonies, 10 \u0026micro;L of the culture was spread on a MacConkey agar plate. For all experiments, pink colonies were selected from the plate and grown in a 600 mL Luria Bertani (LB) medium. The cultures were incubated in a shaker incubator maintained at 37\u0026deg;C with rotation at 180 rpm. The culture was monitored every 2 h until an optical density (OD) of approximately 0.65\u0026ndash;0.75 was achieved. Optical density was measured in triplicates. To compare the OD values, sterile blank LB solution was incubated under similar conditions. This was used as blank for all measurements. For all experiments, a blank plate and a plate with the blank solution were incubated along with the different experimental setups to ensure the sterility of the incubator and culture media.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eCulture Media Preparation\u003c/h3\u003e\n\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eFor all experiments with \u003cem\u003eE. Coli\u003c/em\u003e, three different agar media were used: Luria Bertani (LB) agar (M1151, HiMedia, USA), MacConkey agar (M7408, Millipore, USA), and HiChrome Agar (M1353R, HiMedia, USA). For preparing the LB agar. For the preparation of MacConkey Agar, 30 gm of the agar was mixed with 600 mL distilled water. For the preparation of HiChrome Agar, 34.08 gm was mixed in 600 mL distilled water. All the agar media and liquid cultures were autoclaved at 121\u0026deg;C and 15 psi for 30 min.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eMembrane Selection\u003c/h3\u003e\n\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eFor all experiments with membranes, Whatman Grade 470 was used to deliver the sample to agar media. This was selected based on the pore size of the membrane. Before integrating the membrane into the experiment it was washed thoroughly with 70% ethanol, followed by washing with distilled water.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e\n\u003ch3\u003eImage Capturing And Analysis\u003c/h3\u003e\n\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eAll cultured plates were imaged using an in-built phone camera. A customised LED-mounted translucent light diffuser setup (designed for home use) was used to capture images of the cultured plates (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb). Images were captured using iPhone 12. The images were captured at an exposure of 1/875s and ISO 32. Colonies were counted manually using OpenCFU to establish if the system could be quantified using available software as well. No post-capture changes were applied to the images before processing with OpenCFUs.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eAll statistical analyses were performed using GraphPad Prism version 9. For all groups of experiments, an unpaired, non-parametric t-test (Kolmogorov\u0026ndash;Smirnov test) was performed to compare the cumulative distributions and determine the p-value. Results were considered statistically significant at a p-value of 0.1 and a 90% statistical significance.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"References","content":"\u003cp\u003e1. O. Storme, J. Tir\u0026aacute;n Saucedo, A. Garcia-Mora, M. Dehesa-D\u0026aacute;vila, K. G. Naber, Risk factors and predisposing conditions for urinary tract infection. \u003cem\u003eTher. Adv. Urol.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e11\u003c/strong\u003e, 1756287218814382 (2019).\u003c/p\u003e\n\u003cp\u003e2. A. Al-Badr, G. Al-Shaikh, Recurrent Urinary Tract Infections Management in Women: A review. \u003cem\u003eSultan Qaboos Univ. Med. J.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e13\u003c/strong\u003e, 359\u0026ndash;367 (2013).\u003c/p\u003e\n\u003cp\u003e3. D. A. Queremel Milani, I. Jialal, Urinalysis, in \u003cem\u003eStatPearls\u003c/em\u003e (StatPearls Publishing, 2022).\u003c/p\u003e\n\u003cp\u003e4. G. Schmiemann, E. Kniehl, K. Gebhardt, M. M. Matejczyk, E. Hummers-Pradier, The diagnosis of urinary tract infection: A systematic review. \u003cem\u003eDtsch. \u0026Auml;rztebl. Dtsch. Arztebl. Int.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e107\u003c/strong\u003e, 361\u0026ndash;367 (2010).\u003c/p\u003e\n\u003cp\u003e5. D. C. A. Feitosa, M. G. da Silva, C. M. G. de Lima Parada, Accuracy of simple urine tests for diagnosis of urinary tract infections in low-risk pregnant women. \u003cem\u003eRev. Lat. Am Enfermagem.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e17\u003c/strong\u003e, 507\u0026ndash;513 (2009).\u003c/p\u003e\n\u003cp\u003e6. A. K. Mambatta, J. Jayarajan, V. L. Rashme, S. Harini, S. Menon, J. Kuppusamy, Reliability of dipstick assay in predicting urinary tract infection. \u003cem\u003eJ. Fam\u003c/em\u003e\u003cem\u003eily\u0026nbsp;Med. Prim. Care.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e4\u003c/strong\u003e, 265\u0026ndash;268 (2015).\u003c/p\u003e\n\u003cp\u003e7. A. L. Flores-Mireles, J. N. Walker, M. Caparon, S. J. Hultgren, Urinary tract infections: Epidemiology, mechanisms of infection and treatment options. \u003cem\u003eNat. Rev. Microbiol.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e13\u003c/strong\u003e, 269\u0026ndash;284 (2015).\u003c/p\u003e\n\u003cp\u003e8. K. Gupta, L. Grigoryan, B. Trautner, Urinary tract infection. \u003cem\u003eAnn. Intern. Med.\u003c/em\u003e, ITC49\u003cem\u003e.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e167\u003c/strong\u003e, ITC49\u0026ndash;ITC64 (2017).\u003c/p\u003e\n\u003cp\u003e9. C. Carter, J. Stallworth, R. Holleman Chapter 40, Urinary tract disorders, in \u003cem\u003eTextbook of Family Medicine,\u0026nbsp;\u003c/em\u003eed. 8, R. E. Rakel, D. P. Rakel, Eds. (W. B. Saunders, 2012), pp. 899\u0026ndash;927. doi:10.1016/B978-1-4377-1160-8.10040-5.\u003c/p\u003e\n\u003cp\u003e10. H. Sinawe, D. Casadesus, Urine culture, in \u003cem\u003eStatPearls\u003c/em\u003e (StatPearls Publishing, 2022).\u003c/p\u003e\n\u003cp\u003e11. G. R. Naylor, D. Guttmann, The dip-slide: A modified dip-inoculum transport medium for the laboratory diagnosis of infections of the urinary tract. \u003cem\u003eJ. Hyg. (Lond).\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e65\u003c/strong\u003e, 367\u0026ndash;371 (1967).\u003c/p\u003e\n\u003cp\u003e12. J. C. Fung, B. Lucia, E. Clark, M. Berman, J. Goldstein, R. F. D\u0026rsquo;Amato, Primary culture media for routine urine processing. \u003cem\u003eJ. Clin. Microbiol.\u0026nbsp;\u003c/em\u003e\u003cstrong\u003e16\u003c/strong\u003e, 632\u0026ndash;636 (1982).\u003c/p\u003e\n\u003cp\u003e13. S. S. Ahmed, A. Shariq, A. A. Alsalloom, I. H. Babikir, B. N. Alhomoud, Uropathogens and their antimicrobial resistance patterns: Relationship with urinary tract infections. \u003cem\u003eInt. J. Health Sci. (Qassim)\u003c/em\u003e. \u003cstrong\u003e13\u003c/strong\u003e, 48\u0026ndash;55 (2019).\u003c/p\u003e\n\u003cp\u003e14. R. Paul, State of the globe: Rising antimicrobial resistance of pathogens in urinary tract infection. \u003cem\u003eJ. Glob. Infect. Dis.\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, 117\u0026ndash;118 (2018).\u003c/p\u003e\n\u003cp\u003e15. S. A. R. Mortazavi-Tabatabaei, J. Ghaderkhani, A. Nazari, K. Sayehmiri, F. Sayehmiri, I. Pakzad, Pattern of antibacterial resistance in urinary tract infections: A systematic review and meta-analysis. \u003cem\u003eInt. J. Prev. Med.\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, 169 (2019).\u003c/p\u003e\n\u003cp\u003e16. M. Newman, D. A. Curran, Reliability of a dried urine test for comprehensive assessment of urine hormones and metabolites. \u003cem\u003eBMC Chem.\u003c/em\u003e \u003cstrong\u003e15\u003c/strong\u003e, 18 (2021).\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-2247512/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-2247512/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eDiagnosing a urinary tract infection (UTI) is typically a clinical procedure involving multiple steps. The need to perform a test depends on the presence of relevant symptoms. Given the current pandemic situation, visiting a clinic may not be a preferable choice for many users. Many vulnerable groups of patients, namely, males with certain predispositions and pregnant women, may not present with symptoms of UTI, which could give rise to a more complicated situation. Microbial culture provides a definitive diagnosis for the presence of an infection. A home-use culture kit can serve this purpose; however, to our knowledge, no such kit exists. Here, we present a feasibility study of an affordable and easy-to-use home-based setup for quantifying bacterial load in a urine.\u003c/p\u003e \u003cp\u003eTeaser\u003c/p\u003e \u003cp\u003eA home-use system for monitoring progression and management of UTIs.\u003c/p\u003e","manuscriptTitle":"A novel home-use culture mechanism for identifying microbial load in urine samples","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-11-09 18:21:06","doi":"10.21203/rs.3.rs-2247512/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"786bf087-e0dc-4191-bdd4-7f5f7e87f3f4","owner":[],"postedDate":"November 9th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":16784093,"name":"General Microbiology"}],"tags":[],"updatedAt":"2022-11-09T18:21:06+00:00","versionOfRecord":[],"versionCreatedAt":"2022-11-09 18:21:06","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-2247512","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2247512","identity":"rs-2247512","version":["v1"]},"buildId":"wLkW0s4AflPzk-lpfg-fK","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}