{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,14]],"date-time":"2026-08-14T00:16:58Z","timestamp":1786666618374,"version":"build-2736575974"},"reference-count":18,"publisher":"American Society for Microbiology","issue":"6","license":[{"start":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T00:00:00Z","timestamp":1780358400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T00:00:00Z","timestamp":1780358400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.asm.org\/non-commercial-tdm-license"}],"content-domain":{"domain":["journals.asm.org"],"crossmark-restriction":true},"short-container-title":["Microbiol Spectr"],"published-print":{"date-parts":[[2026,6,2]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:sec>\n                    <jats:title\/>\n                    <jats:p>\n                      A substantial proportion of symptomatic patients with urinary tract infections (UTIs) have negative or low-count urine cultures despite clinically compatible presentations. Biofilm-associated bacterial aggregation and the presence of viable bacteria not recovered by standard culture may contribute to this diagnostic gap. Flow cytometry (FACS) can detect these viable cells, but culturability remains essential for species identification and antimicrobial susceptibility testing. We evaluated whether low-concentration dithiothreitol (DTT) can safely disperse urinary biofilm-associated aggregates and improve bacterial recovery from urine samples. Seventy-two clinical urine samples were processed in parallel (untreated vs 0.1% DTT-treated). Viability was quantified using SYTO9\/PI-based flow cytometry with bead-normalized bacterial counts. Culturability was assessed on chromogenic media. Comparative analyses included paired statistics, Bland\u2013Altman agreement, and correlation between viable and culturable fractions. DTT (0.1%) did not alter bacterial viability (\n                      <jats:italic toggle=\"yes\">P<\/jats:italic>\n                      = 0.47), confirming its non-toxicity at this concentration. In contrast, DTT significantly increased CFU recovery (median: 10 to 5.5 \u00d7 10\u00b3 CFU\/mL;\n                      <jats:italic toggle=\"yes\">P<\/jats:italic>\n                      &lt; 0.0001), converting several previously negative or low-count samples into positive cultures. Agreement between viable and culturable fractions improved after DTT treatment, primarily through reduced systematic bias in Bland\u2013Altman analysis, while correlation coefficients remained similar (r: 0.44 vs 0.45). A persistent discrepancy between FACS-derived viable counts and culture-based counts suggests the presence of viable bacterial populations not fully recovered by standard culture conditions, findings that are consistent with but do not directly demonstrate the presence of VBNC subpopulations. Low-dose DTT is a safe and effective pre-analytical treatment that markedly improves culture sensitivity without compromising bacterial viability. These findings support further investigation of DTT-assisted processing as a potential strategy to reduce culture underestimation in urinary diagnostics and to better characterize viable bacterial populations not detected by standard culture methods.\n                    <\/jats:p>\n                    <jats:sec>\n                      <jats:title>IMPORTANCE<\/jats:title>\n                      <jats:p>Standard urine culture may fail to detect the full spectrum of bacteria present in urinary tract infections, particularly when microorganisms are embedded within mucus, biofilm-like aggregates, or enter a viable but non-culturable state. These hidden bacterial populations may contribute to persistent symptoms or recurrent infections while remaining undetected by routine culture methods. Our findings suggest that pre-treating urine samples with a low concentration of dithiothreitol may help disperse biofilm-like aggregates while preserving bacterial viability. When combined with flow cytometry, this approach may allow a more comprehensive estimation of the viable bacterial fraction and, in some cases, may increase the likelihood of bacterial recovery by culture in samples that would otherwise appear negative. Because the procedure relies on inexpensive reagents and techniques compatible with routine laboratory workflows, it may represent a practical adjunct to conventional diagnostics. Further studies are needed to confirm its clinical impact.<\/jats:p>\n                    <\/jats:sec>\n                  <\/jats:sec>","DOI":"10.1128\/spectrum.03910-25","type":"journal-article","created":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T13:01:50Z","timestamp":1777986110000},"update-policy":"https:\/\/doi.org\/10.1128\/asmj-crossmark-policy-page","source":"Crossref","is-referenced-by-count":1,"title":["Reducing culture underestimation in urine: flow cytometry\u2013guided validation of low-dose DTT pre-treatment for biofilm dispersal"],"prefix":"10.1128","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8760-1292","authenticated-orcid":true,"given":"Luigi Regenburgh","family":"De La Motte","sequence":"first","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica","place":["Milan, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ivan","family":"Muradore","sequence":"additional","affiliation":[{"name":"F.L.O.R.A.L. facility IRCCS MultiMedica","place":["Milan, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabiana","family":"Giarritiello","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/04z08z627","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Medicine and Health Sciences \u201cV. Tiberio\u201d, University of Molise","place":["Campobasso, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erica","family":"Stef\u00e0no","sequence":"additional","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica","place":["Milan, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Loredana","family":"Deflorio","sequence":"additional","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica","place":["Milan, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5206-540X","authenticated-orcid":true,"given":"Lorenzo","family":"Drago","sequence":"additional","affiliation":[{"name":"UOC Laboratory of Clinical Medicine with Specialized Areas, IRCCS MultiMedica","place":["Milan, Italy"]},{"id":[{"id":"https:\/\/ror.org\/00wjc7c48","id-type":"ROR","asserted-by":"publisher"}],"name":"Department of Biomedical Health Sciences, University of Milan","place":["Milan, Italy"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"235","reference":[{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1038\/nrmicro3432"},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.3389\/fmicb.2019.00040"},{"key":"e_1_3_4_4_2","doi-asserted-by":"publisher","DOI":"10.1155\/2018\/7624857"},{"key":"e_1_3_4_5_2","doi-asserted-by":"publisher","DOI":"10.1128\/AEM.02932-09"},{"key":"e_1_3_4_6_2","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.42.2.753-758.2004"},{"key":"e_1_3_4_7_2","doi-asserted-by":"publisher","DOI":"10.1007\/s00216-010-3646-3"},{"key":"e_1_3_4_8_2","doi-asserted-by":"publisher","DOI":"10.1128\/JCM.01452-18"},{"key":"e_1_3_4_9_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.cmi.2017.04.004"},{"key":"e_1_3_4_10_2","doi-asserted-by":"publisher","DOI":"10.3389\/fcimb.2016.00014"},{"key":"e_1_3_4_11_2","doi-asserted-by":"publisher","DOI":"10.3390\/pharma4040021"},{"key":"e_1_3_4_12_2","doi-asserted-by":"publisher","DOI":"10.1016\/j.amjms.2018.11.009"},{"key":"e_1_3_4_13_2","doi-asserted-by":"publisher","DOI":"10.1186\/s12879-021-05893-3"},{"key":"e_1_3_4_14_2","doi-asserted-by":"publisher","DOI":"10.3389\/fcimb.2023.1119020"},{"key":"e_1_3_4_15_2","doi-asserted-by":"publisher","DOI":"10.1186\/s12866-015-0376-x"},{"key":"e_1_3_4_16_2","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0281118"},{"key":"e_1_3_4_17_2","doi-asserted-by":"publisher","DOI":"10.1007\/s00264-023-05714-z"},{"key":"e_1_3_4_18_2","doi-asserted-by":"publisher","DOI":"10.3390\/microorganisms13040700"},{"key":"e_1_3_4_19_2","doi-asserted-by":"publisher","DOI":"10.2147\/DMSO.S51792"}],"container-title":["Microbiology Spectrum"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/spectrum.03910-25","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.asm.org\/doi\/pdf\/10.1128\/spectrum.03910-25","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T13:12:43Z","timestamp":1781701963000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.asm.org\/doi\/10.1128\/spectrum.03910-25"}},"subtitle":[],"editor":[{"given":"Ilana","family":"Kolodkin-Gal","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2026,6,2]]},"references-count":18,"journal-issue":{"issue":"6","published-print":{"date-parts":[[2026,6,2]]}},"alternative-id":["10.1128\/spectrum.03910-25"],"URL":"https:\/\/doi.org\/10.1128\/spectrum.03910-25","relation":{},"ISSN":["2165-0497"],"issn-type":[{"value":"2165-0497","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,2]]},"assertion":[{"value":"2025-12-03","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-03-25","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-05-05","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e03910-25"}}