{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T08:03:32Z","timestamp":1792656212585,"version":"4.5.0"},"reference-count":33,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,10,22]],"date-time":"2022-10-22T00:00:00Z","timestamp":1666396800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Blood culture-negative infective endocarditis (BCNIE) poses a significant challenge in determining the best antibiotic regimen for this life-threatening infection, which should be treated with as specific and effective a regimen as feasible. The goal of this study was to determine the prevalence of BCNIE among definite infective endocarditis (IE) cases and to study the impact of a molecular and serological diagnostic approach in defining the microbiological origin of BCNIE. This study included 94 definite IE cases. Serum and blood samples from BCNIE patients were tested using serological, broad-range PCR, and sequencing assays. Valve tissue sections obtained from 42 operated patients were subjected to culture and molecular studies. BCNIE accounted for 63 (67%) of the cases. Of these cases, blood PCR followed by sequencing could diagnose 11 cases. Zoonotic infective endocarditis was detected in 7 (11%) patients by serology and PCR (four Brucella, two Bartonella, and one Coxiella). Sequencing of valve PCR bands revealed 30 positive cases. Therefore, the percentage of BCNIE with unidentified etiology was reduced from 67% to 27.7% through a combination of all diagnostic procedures utilized in our study. Blood and valve PCR and sequencing assays are valuable techniques for the etiological diagnosis of BCNIE, especially in cases with previous antibiotic therapy. However, these tests should be used as part of a larger diagnostic strategy that includes serology, microscopy, and valve culture. The use of an automated blood culture system, and proper blood culture collection before ordering antibiotics, will guide IE etiological diagnosis.<\/jats:p>","DOI":"10.3390\/pathogens11111220","type":"journal-article","created":{"date-parts":[[2022,10,24]],"date-time":"2022-10-24T08:19:06Z","timestamp":1666599546000},"page":"1220","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Molecular and Serological Diagnostic Approach to Define the Microbiological Origin of Blood Culture-Negative Infective Endocarditis"],"prefix":"10.3390","volume":"11","author":[{"given":"Amira H.","family":"El-Ashry","sequence":"first","affiliation":[{"name":"Medical Microbiology & Immunology Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8473-6116","authenticated-orcid":false,"given":"Khaled","family":"Saad","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Faculty of Medicine, Assiut University, Assiut 71111, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmed A.","family":"Obiedallah","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, Assiut University, Assiut 71111, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amira","family":"Elhoufey","sequence":"additional","affiliation":[{"name":"Department of Community Health Nursing, Faculty of Nursing, Assiut University, Assiut 71111, Egypt"},{"name":"Department of Community Health Nursing, Alddrab University College, Jazan University, Jazan 45142, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hamad Ghaleb","family":"Dailah","sequence":"additional","affiliation":[{"name":"Research and Scientific Studies Unit, College of Nursing, Jazan University, Jazan 45142, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed Salah A.","family":"Hussein","sequence":"additional","affiliation":[{"name":"Cardiovascular Medicine Department, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"459","DOI":"10.1007\/s15010-015-0863-x","article-title":"Diagnosis of blood culture-negative endocarditis and clinical comparison between blood culture-negative and blood culture-positive cases","volume":"44","author":"Lamas","year":"2016","journal-title":"Infection"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5238","DOI":"10.1128\/JCM.43.10.5238-5242.2005","article-title":"Contribution of Systematic Serological Testing in Diagnosis of Infective Endocarditis","volume":"43","author":"Raoult","year":"2005","journal-title":"J. Clin. Microbiol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"244","DOI":"10.1007\/s11908-010-0111-6","article-title":"Molecular Methods for Diagnosis of Infective Endocarditis","volume":"12","author":"Moter","year":"2010","journal-title":"Curr. Infect. Dis. Rep."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1128\/CMR.14.1.177-207.2001","article-title":"Endocarditis Due to Rare and Fastidious Bacteria","volume":"14","author":"Brouqui","year":"2001","journal-title":"Clin. Microbiol. Rev."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"763","DOI":"10.1128\/JCM.41.2.763-766.2003","article-title":"Molecular Diagnosis of Infective Endocarditis by PCR Amplification and Direct Sequencing of DNA from Valve Tissue","volume":"41","author":"Gauduchon","year":"2003","journal-title":"J. Clin. Microbiol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1086\/375592","article-title":"Etiologic Diagnosis of Infective Endocarditis by Broad-Range Polymerase Chain Reaction: A 3-Year Experience","volume":"37","author":"Bosshard","year":"2003","journal-title":"Clin. Infect. Dis."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2733","DOI":"10.1128\/jcm.35.11.2733-2739.1997","article-title":"Molecular diagnosis of bacterial endocarditis by broad-range PCR amplification and direct sequencing","volume":"35","author":"Goldenberger","year":"1997","journal-title":"J. Clin. Microbiol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"633","DOI":"10.1086\/313753","article-title":"Proposed Modifications to the Duke Criteria for the Diagnosis of Infective Endocarditis","volume":"30","author":"Li","year":"2000","journal-title":"Clin. Infect. Dis."},{"key":"ref_9","unstructured":"Daniel, W. (1999). Biostatistics: A Foundation for Analysis in the Health Sciences, John Wiley & Sons. [7th ed.]."},{"key":"ref_10","first-page":"12","article-title":"Infective endocarditis in cardiac setting in Dakar: Descriptive study about 39 cases","volume":"7","author":"Ndiaye","year":"2010","journal-title":"Pan Afr. Med. J."},{"key":"ref_11","unstructured":"Forbes, B.A., Sahm, D.F., and Weissfeld, A.S. (2007). Bailey and Scott\u2019s Diagnostic Microbiology, Mosby Elsevier. [12th ed.]."},{"key":"ref_12","first-page":"315","article-title":"Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics","volume":"Volume 18","author":"Innis","year":"1990","journal-title":"PCR Protocols: A Guide to Methods and Applications"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3509","DOI":"10.1128\/JCM.40.9.3509-3511.2002","article-title":"Evaluation of Dipstick Serologic Tests for Diagnosis of Brucellosis and Typhoid Fever in Egypt","volume":"40","author":"Ismail","year":"2002","journal-title":"J. Clin. Microbiol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"523","DOI":"10.1007\/s15010-015-0761-2","article-title":"Impact of serology and molecular methods on improving the microbiologic diagnosis of infective endocarditis in Egypt","volume":"43","author":"AbdulRahman","year":"2015","journal-title":"Infection"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"190","DOI":"10.1111\/j.1600-0463.2008.00942.x","article-title":"Broad-range PCR and sequencing in routine diagnosis of infective endocarditis","volume":"116","author":"Voldstedlund","year":"2008","journal-title":"APMIS"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"673","DOI":"10.1080\/00365540110026764","article-title":"Molecular diagnosis of infective endocarditis? A new Duke\u2019s criterion","volume":"33","author":"Millar","year":"2001","journal-title":"Scand. J. Infect. Dis."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"216","DOI":"10.3201\/eid1102.040668","article-title":"Bacterial Zoonoses and Infective Endocarditis, Algeria","volume":"11","author":"Benslimani","year":"2005","journal-title":"Emerg. Infect. Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/j.ijcard.2003.10.043","article-title":"Characteristics of infective endocarditis in a developing country-clinical profile and outcome in 192 Indian patients, 1992\u20132001","volume":"98","author":"Garg","year":"2005","journal-title":"Int. J. Cardiol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0924-8579(01)00344-2","article-title":"A retrospective review of 228 episodes of infective endocarditis where rheumatic valvular disease is still common","volume":"18","author":"Akova","year":"2001","journal-title":"Int. J. Antimicrob. Agents"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1016\/j.jsha.2011.04.002","article-title":"Clinical and microbiological profiles of infective endocarditis in a tertiary hospital in Aseer region, Saudi Arabia","volume":"23","author":"Assiri","year":"2011","journal-title":"J. Saudi Heart Assoc."},{"key":"ref_21","first-page":"2","article-title":"Clinical features and outcome of infective endocarditis in yemeni patients treated with empirical antibiotic therapy","volume":"11","author":"Khaled","year":"2010","journal-title":"Heart Views"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1001\/jama.288.1.75","article-title":"Changing Profile of Infective EndocarditisResults of a 1-Year Survey in France","volume":"288","author":"Hoen","year":"2002","journal-title":"JAMA"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"472","DOI":"10.1016\/j.jinf.2011.04.010","article-title":"16S rDNA sequencing of valve tissue improves microbiological diagnosis in surgically treated patients with infective endocarditis","volume":"62","author":"Vondracek","year":"2011","journal-title":"J. Infect."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1086\/653675","article-title":"Comprehensive Diagnostic Strategy for Blood Culture\u2013Negative Endocarditis: A Prospective Study of 819 New Cases","volume":"51","author":"Fournier","year":"2010","journal-title":"Clin. Infect. Dis."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.ehj.2012.08.001","article-title":"Molecular and serological techniques for the diagnosis of culture negative infective endocarditis in Alexandria Main University Hospital","volume":"65","author":"Sadaka","year":"2013","journal-title":"Egypt. Heart J."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"923","DOI":"10.1016\/j.trstmh.2007.04.020","article-title":"Seroprevalences and local variation of human and livestock brucellosis in two villages in Gharbia Governorate, Egypt","volume":"101","author":"Kabbash","year":"2007","journal-title":"Trans. R. Soc. Trop. Med. Hyg."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"503","DOI":"10.4269\/ajtmh.2005.72.503","article-title":"High prevalence of bartonella quintana endocarditis in sfax, tunisia","volume":"72","author":"Znazen","year":"2005","journal-title":"Am. J. Trop. Med. Hyg."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1136\/heart.89.3.258","article-title":"Blood culture negative endocarditis: Analysis of 63 cases presenting over 25 years","volume":"89","author":"Lamas","year":"2003","journal-title":"Heart"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1097\/00005792-200007000-00007","article-title":"Aspergillus Valve Endocarditis in Patients without Prior Cardiac Surgery","volume":"79","author":"Gumbo","year":"2000","journal-title":"Medicine"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"e1040","DOI":"10.1016\/j.ijid.2010.08.005","article-title":"Aspergillus endocarditis: A review of the literature","volume":"14","author":"Kalokhe","year":"2010","journal-title":"Int. J. Infect. Dis."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"530","DOI":"10.1093\/mmy\/myu017","article-title":"Evaluation of noninvasive methods for the diagnosis of fungal endocarditis","volume":"52","author":"Badiee","year":"2014","journal-title":"Med. Mycol."},{"key":"ref_32","first-page":"195","article-title":"The role of nucleic acid amplification techniques (NAATs) in the diagnosis of infective endocarditis","volume":"17","author":"Rodger","year":"2010","journal-title":"Br. J. Cardiol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2061","DOI":"10.1007\/s10096-014-2145-4","article-title":"Service evaluation to establish the sensitivity, specificity and additional value of broad range 16S rDNA PCR for the diagnosis of infective endocarditis from resected endocardial material in patients from eight UK and Ireland hospitals","volume":"33","author":"Harris","year":"2014","journal-title":"Eur. J. Clin. Microbiol. Infect. 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