{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T16:50:46Z","timestamp":1790700646505,"version":"4.1.0"},"reference-count":26,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,5,9]],"date-time":"2024-05-09T00:00:00Z","timestamp":1715212800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Background: This study was designed to assess the diagnostic utility for FIP of cytology, protein measurement and RT-PCR for feline coronaviruses (FCoV) on aqueous humor (AH), since little information is currently available. Methods: AH samples (n = 85) were collected post-mortem from 13 cats with effusive FIP (E-FIP), 15 with non-effusive FIP (NE-FIP) and 16 without FIP, to perform cytology (n = 83) and RT-PCR (n = 66) and to calculate their sensitivity, specificity and positive and negative likelihood ratios (LR+ and LR\u2212). The protein concentration was measured on 80 fluids. Results: The proportion of RT-PCR positive samples did not differ among groups, while positive cytology was more frequent in samples with FIP (p = 0.042) or positive RT-PCR (p = 0.007). Compared with other groups, the protein concentration was higher in samples with NE-FIP (p = 0.017), positive RT-PCR (p = 0.005) or positive cytology (p &lt; 0.001). The specificity of cytology together with RT-PCR, cytology alone, RT-PCR alone and cytological proteinaceous background were 90.0%, 84.6%, 70.0%, 61.5%, and the LRs 3.48, 2.65, 1.83, 1.64, respectively. However, their sensitivities were low (34.8\u201363.0%) and their LR\u2212 high (0.60\u20130.72). Conclusions: Based on the LR+, cytology and\/or RT-PCR may support the diagnosis when the pre-test probability of FIP is high. The concentration of intraocular protein is a promising marker, especially in NE-FIP.<\/jats:p>","DOI":"10.3390\/vetsci11050207","type":"journal-article","created":{"date-parts":[[2024,5,9]],"date-time":"2024-05-09T03:34:19Z","timestamp":1715225659000},"page":"207","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Clinicopathological and Molecular Analysis of Aqueous Humor for the Diagnosis of Feline Infectious Peritonitis"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8529-572X","authenticated-orcid":false,"given":"Angelica","family":"Stranieri","sequence":"first","affiliation":[{"name":"Department of Veterinary Medicine and Animal Sciences (Divas), University of Milan, Via dell\u2019Universit\u00e0 6, 26900 Lodi, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2111-108X","authenticated-orcid":false,"given":"Stefania","family":"Lauzi","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine and Animal Sciences (Divas), University of Milan, Via dell\u2019Universit\u00e0 6, 26900 Lodi, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7117-7987","authenticated-orcid":false,"given":"Saverio","family":"Paltrinieri","sequence":"additional","affiliation":[{"name":"Department of Veterinary Medicine and Animal Sciences (Divas), University of Milan, Via dell\u2019Universit\u00e0 6, 26900 Lodi, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"228","DOI":"10.1177\/1098612X18758592","article-title":"Diagnosis of feline infectious peritonitis: Update on evidence supporting available tests","volume":"20","author":"Tasker","year":"2018","journal-title":"J. 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