{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,7]],"date-time":"2026-11-07T02:36:24Z","timestamp":1794018984097,"version":"4.8.0"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,3]],"date-time":"2021-01-03T00:00:00Z","timestamp":1609632000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Klebsiella pneumoniae is a Gram-negative, rod-shaped bacterium, responsible for hospital and community acquired pneumonia, urinary tract and wound infections, and bloodstream dissemination. K. pneumoniae infection in pregnancy, leading to acute chorioamnionitis (AC), preterm premature rupture of membranes (PPROM) and early pregnancy loss in the second trimester, has been rarely reported. Herein, we present a case of K. pneumoniae AC that caused intrauterine fetal demise (IUFD) at 19 weeks + 5 days. The 36-year-old mother was admitted at 18 weeks + 1 day of gestation for threatened abortion. IUFD occurred 11 days after. Fetal postmortem showed severe AC and funisitis, neutrophils within alveoli and intestinal lumen, associated with rod-like bacteria. Fetal blood and lung cultures grew K. pneumoniae, \u03b2-lactamase-non-producing strain. Antibiogram revealed sensitivity for piperacillin\/tazobactam. Three days after IUFD, the mother presented with fever (37.8 \u00b0C) which persisted for one week. Maternal blood and urine cultures were negative. According to fetal microbiological results, available 6 days after IUFD, initial treatment with amoxicillin\/clavulanic acid was replaced with piperacillin\/tazobactam with full patient recovery. Therefore, in the event of PPROM and IUFD, fetal microbiological investigations should always be performed to isolate the proper etiologic agent and start the correct medical treatment.<\/jats:p>","DOI":"10.3390\/microorganisms9010096","type":"journal-article","created":{"date-parts":[[2021,1,3]],"date-time":"2021-01-03T19:54:46Z","timestamp":1609703686000},"page":"96","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Klebsiella pneumoniae Chorioamnionitis: An Underrecognized Cause of Preterm Premature Rupture of Membranes in the Second Trimester"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4889-1944","authenticated-orcid":false,"given":"Maria Paola","family":"Bonasoni","sequence":"first","affiliation":[{"name":"Pathology Unit, Azienda Unit\u00e0 Sanitaria Locale-IRCCS di Reggio Emilia, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2299-5160","authenticated-orcid":false,"given":"Andrea","family":"Palicelli","sequence":"additional","affiliation":[{"name":"Pathology Unit, Azienda Unit\u00e0 Sanitaria Locale-IRCCS di Reggio Emilia, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giulia","family":"Dalla Dea","sequence":"additional","affiliation":[{"name":"Pathology Unit, \u201cMaggiore della Carit\u00e0\u201d Hospital, 28100 Novara, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppina","family":"Comitini","sequence":"additional","affiliation":[{"name":"Department of Obstetrics &amp; Gynaecology, Azienda Unit\u00e0 Sanitaria Locale-IRCCS di Reggio Emilia, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paola","family":"Nardini","sequence":"additional","affiliation":[{"name":"Clinical Microbiology Laboratory, IRCCS Arcispedale Santa Maria Nuova, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Loredana","family":"Vizzini","sequence":"additional","affiliation":[{"name":"Clinical Microbiology Laboratory, IRCCS Arcispedale Santa Maria Nuova, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Russello","sequence":"additional","affiliation":[{"name":"Clinical Microbiology Laboratory, IRCCS Arcispedale Santa Maria Nuova, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcellino","family":"Bardaro","sequence":"additional","affiliation":[{"name":"Clinical Microbiology Laboratory, IRCCS Arcispedale Santa Maria Nuova, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6521-5887","authenticated-orcid":false,"given":"Edoardo","family":"Carretto","sequence":"additional","affiliation":[{"name":"Clinical Microbiology Laboratory, IRCCS Arcispedale Santa Maria Nuova, 42122 Reggio Emilia, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Baergen, R. 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