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Tasker S, Addie DD, Egberink H, Hofmann-Lehmann R, Hosie MJ, Truyen U, Belák S, Boucraut-Baralon C, Frymus T, Lloret A, Marsilio F, Pennisi MG, Thiry E, Möstl K, Hartmann K. Feline Infectious Peritonitis: European Advisory Board on Cat Diseases Guidelines. Viruses 2023; 15:1847. [PMID: 37766254 PMCID: PMC10535984 DOI: 10.3390/v15091847] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/19/2023] [Accepted: 08/23/2023] [Indexed: 09/29/2023] Open
Abstract
Feline coronavirus (FCoV) is a ubiquitous RNA virus of cats, which is transmitted faeco-orally. In these guidelines, the European Advisory Board on Cat Diseases (ABCD) presents a comprehensive review of feline infectious peritonitis (FIP). FCoV is primarily an enteric virus and most infections do not cause clinical signs, or result in only enteritis, but a small proportion of FCoV-infected cats develop FIP. The pathology in FIP comprises a perivascular phlebitis that can affect any organ. Cats under two years old are most frequently affected by FIP. Most cats present with fever, anorexia, and weight loss; many have effusions, and some have ocular and/or neurological signs. Making a diagnosis is complex and ABCD FIP Diagnostic Approach Tools are available to aid veterinarians. Sampling an effusion, when present, for cytology, biochemistry, and FCoV RNA or FCoV antigen detection is very useful diagnostically. In the absence of an effusion, fine-needle aspirates from affected organs for cytology and FCoV RNA or FCoV antigen detection are helpful. Definitive diagnosis usually requires histopathology with FCoV antigen detection. Antiviral treatments now enable recovery in many cases from this previously fatal disease; nucleoside analogues (e.g., oral GS-441524) are very effective, although they are not available in all countries.
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Affiliation(s)
- Séverine Tasker
- Bristol Veterinary School, University of Bristol, Bristol BS40 5DU, UK
- Linnaeus Veterinary Limited, Shirley, Solihull B90 4BN, UK
| | - Diane D. Addie
- Independent Researcher, 64000 Pyrénées Aquitaine, France;
| | - Herman Egberink
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, University of Utrecht, 3584 CL Utrecht, The Netherlands;
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland;
| | - Margaret J. Hosie
- MRC-University of Glasgow Centre for Virus Research, Garscube Estate, Glasgow G61 1QH, UK;
| | - Uwe Truyen
- Institute of Animal Hygiene and Veterinary Public Health, University of Leipzig, 04103 Leipzig, Germany;
| | - Sándor Belák
- Department of Biomedical Sciences and Veterinary Public Health (BVF), Swedish University of Agricultural Sciences (SLU), P.O. Box 7036, 750 07 Uppsala, Sweden;
| | | | - Tadeusz Frymus
- Department of Small Animal Diseases with Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences-SGGW, 02-787 Warsaw, Poland;
| | - Albert Lloret
- Fundació Hospital Clínic Veterinari, Universitat Autònoma de Barcelona, Bellaterra, 08193 Barcelona, Spain;
| | - Fulvio Marsilio
- Faculty of Veterinary Medicine, Università Degli Studi di Teramo, 64100 Teramo, Italy;
| | - Maria Grazia Pennisi
- Dipartimento di Scienze Veterinarie, Università di Messina, 98168 Messina, Italy;
| | - Etienne Thiry
- Veterinary Virology and Animal Viral Diseases, Department of Infectious and Parasitic Diseases, FARAH Research Centre, Faculty of Veterinary Medicine, Liège University, B-4000 Liège, Belgium;
| | - Karin Möstl
- Institute of Virology, Department for Pathobiology, University of Veterinary Medicine, 1210 Vienna, Austria;
| | - Katrin Hartmann
- LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, LMU Munich, 80539 Munich, Germany;
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Thayer V, Gogolski S, Felten S, Hartmann K, Kennedy M, Olah GA. 2022 AAFP/EveryCat Feline Infectious Peritonitis Diagnosis Guidelines. J Feline Med Surg 2022; 24:905-933. [PMID: 36002137 PMCID: PMC10812230 DOI: 10.1177/1098612x221118761] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
CLINICAL IMPORTANCE Feline infectious peritonitis (FIP) is one of the most important infectious diseases and causes of death in cats; young cats less than 2 years of age are especially vulnerable. FIP is caused by a feline coronavirus (FCoV). It has been estimated that around 0.3% to 1.4% of feline deaths at veterinary institutions are caused by FIP. SCOPE This document has been developed by a Task Force of experts in feline clinical medicine as the 2022 AAFP/EveryCat Feline Infectious Peritonitis Diagnosis Guidelines to provide veterinarians with essential information to aid their ability to recognize cats presenting with FIP. TESTING AND INTERPRETATION Nearly every small animal veterinary practitioner will see cases. FIP can be challenging to diagnose owing to the lack of pathognomonic clinical signs or laboratory changes, especially when no effusion is present. A good understanding of each diagnostic test's sensitivity, specificity, predictive value, likelihood ratio and diagnostic accuracy is important when building a case for FIP. Before proceeding with any diagnostic test or commercial laboratory profile, the clinician should be able to answer the questions of 'why this test?' and 'what do the results mean?' Ultimately, the approach to diagnosing FIP must be tailored to the specific presentation of the individual cat. RELEVANCE Given that the disease is fatal when untreated, the ability to obtain a correct diagnosis is critical. The clinician must consider the individual patient's history, signalment and comprehensive physical examination findings when selecting diagnostic tests and sample types in order to build the index of suspicion 'brick by brick'. Research has demonstrated efficacy of new antivirals in FIP treatment, but these products are not legally available in many countries at this time. The Task Force encourages veterinarians to review the literature and stay informed on clinical trials and new drug approvals.
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Scalia B, Caine A, Pittaway R, Cherubini GB. Feline temporal lobe epilepsy: seven cases of hippocampal and piriform lobe necrosis in England and literature review. J Feline Med Surg 2022; 24:596-608. [PMID: 34355984 PMCID: PMC11104249 DOI: 10.1177/1098612x211035049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
CASE SERIES SUMMARY Seven cases of feline hippocampal and piriform lobe necrosis (FHN) are described, with particular emphasis on clinical, radiographic and histopathological correlations. FHN is an uncommon acute epileptic condition resembling human autoimmune limbic encephalitis and temporal lobe epilepsy. Seizures are typically focal and feature uni- or bilateral orofacial or head twitching, hypersalivation, lip smacking, mydriasis, vocalisation and motionless staring, with inter-ictal behavioural changes such as unprovoked aggression and rapid running. Emerging evidence supports an autoimmune aetiology, although disruption of hippocampal architecture secondary to brain neoplasia has also been recognised. Most commonly, however, the underlying cause remains unknown. Diagnosis is achieved clinically and with brain MRI; electroencephalography and voltage-gated potassium channel-complex autoantibodies are currently the subject of research. Affected cats are frequently refractory to conventional antiepileptic treatment. RELEVANCE AND NOVEL INFORMATION Following a review of the literature, including potential complicating factors and comparisons with human medicine, the hippocampus and piriform lobe are proposed as the neuroanatomical localisation for focal seizures with orofacial involvement in cats, regardless of aetiology.
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Affiliation(s)
| | - Abby Caine
- Dick White Referrals, Six Mile Bottom, UK
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Bakhtazad A, Garmabi B, Joghataei MT. Neurological manifestations of coronavirus infections, before and after COVID-19: a review of animal studies. J Neurovirol 2021; 27:864-884. [PMID: 34727365 PMCID: PMC8561685 DOI: 10.1007/s13365-021-01014-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 07/15/2021] [Accepted: 08/20/2021] [Indexed: 12/12/2022]
Abstract
Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus, which was first identified in December 2019 in China, has resulted in a yet ongoing viral pandemic. Coronaviridae could potentially cause several disorders in a wide range of hosts such as birds and mammals. Although infections caused by this family of viruses are predominantly limited to the respiratory tract, Betacoronaviruses are potentially able to invade the central nervous system (CNS) as well as many other organs, thereby inducing neurological damage ranging from mild to lethal in both animals and humans. Over the past two decades, three novel CoVs, SARS-CoV-1, MERS-CoV, and SARS-CoV-2, emerging from animal reservoirs have exhibited neurotropic properties causing severe and even fatal neurological diseases. The pathobiology of these neuroinvasive viruses has yet to be fully known. Both clinical features of the previous CoV epidemics (SARS-CoV-1 and MERS-CoV) and lessons from animal models used in studying neurotropic CoVs, especially SARS and MERS, constitute beneficial tools in comprehending the exact mechanisms of virus implantation and in illustrating pathogenesis and virus dissemination pathways in the CNS. Here, we review the animal research which assessed CNS infections with previous more studied neurotropic CoVs to demonstrate how experimental studies with appliable animal models can provide scientists with a roadmap in the CNS impacts of SARS-CoV-2. Indeed, animal studies can finally help us discover the underlying mechanisms of damage to the nervous system in COVID-19 patients and find novel therapeutic agents in order to reduce mortality and morbidity associated with neurological complications of SARS-CoV-2 infection.
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Affiliation(s)
- Atefeh Bakhtazad
- Cellular and Molecular Research Center (CMRC), Iran University of Medical Sciences, 1449614535 Tehran, Iran
| | - Behzad Garmabi
- School of Medicine, Shahroud University of Medical Sciences, Haft-Tir Sq, University Blv, 3614773947 Shahroud, Iran
| | - Mohammad Taghi Joghataei
- Cellular and Molecular Research Center (CMRC), Iran University of Medical Sciences, 1449614535 Tehran, Iran
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Chen X, Yu H, Mei T, Chen B, Chen L, Li S, Zhang X, Sun X. SARS-CoV-2 on the ocular surface: is it truly a novel transmission route? Br J Ophthalmol 2021; 105:1190-1195. [PMID: 32788324 PMCID: PMC8380887 DOI: 10.1136/bjophthalmol-2020-316263] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 05/29/2020] [Accepted: 07/07/2020] [Indexed: 12/18/2022]
Abstract
Since December 2019, the novel COVID-19 outbreak has spread rapidly around the globe and infected millions of people. Although the major transmission route of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is considered to be airborne droplets and close contact, the ocular transmission route has been reported with great concern. The current work summarises the characteristics of SARS-CoV-2, the ocular distribution of the major SARS-CoV-2 binding protein, and the experimental and clinical evidence of the ocular transmission route. Although it seems that the likelihood of the ocular surface being an infection gateway is low, SARS-CoV-2 infection or transmission via the ocular surface may cause conjunctivitis and other ocular discomfort. Therefore, good eye protection is an essential safeguard procedure, especially for medical staff.
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Affiliation(s)
- Xuhui Chen
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Huimin Yu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ting Mei
- Department of Nursing, Liyuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bo Chen
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Liwen Chen
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shanling Li
- Department of Nursing, Liyuan Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xian Zhang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xufang Sun
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Grapes NJ, Taylor-Brown FE, Volk HA, De Decker S. Clinical reasoning in feline vestibular syndrome: which presenting features are the most important? J Feline Med Surg 2021; 23:669-678. [PMID: 33176542 PMCID: PMC10812200 DOI: 10.1177/1098612x20970869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVES The aim of this study was to evaluate whether clinical variables from the history, clinical presentation, and physical and neurological examinations of cats with vestibular syndrome were statistically predictive of the underlying diagnosis. METHODS In total, 174 cats presenting with vestibular syndrome between January 2010 and May 2019 were investigated. Univariate statistical analysis of clinical variables was performed and those statistically associated with a diagnosis were retained for multivariable binary logistic regression modelling. RESULTS The seven most prevalent diagnoses represented 95% of vestibular presentations, which included: otitis media/interna (n = 48), idiopathic vestibular syndrome (n = 39), intracranial neoplasia (n = 24), middle ear polyp (n = 17), feline infectious peritonitis (n = 13), thiamine deficiency (n = 13) and intracranial empyema (n = 11). Idiopathic vestibular syndrome was commonly associated with non-purebred cats and had 17.8 times the odds of an improving clinical progression (95% confidence interval [CI] 1.3-250.0; P = 0.03). Intracranial neoplasia was associated with older age and chronic onset of clinical signs, and was significantly more likely to have a central vestibular neuroanatomical localisation (95% CI 8.5-344,349,142.0; P = 0.015) with postural deficits on neurological examination. Thiamine deficiency was more common in female cats, with 52.6 times the odds of a waxing and waning clinical progression (95% CI 1.2-1000; P = 0.038) and 6.8 times the odds of presenting with bilateral vestibular signs (95% CI 1.0-45.7; P = 0.047) and wide excursions of the head (95% CI 1.0-45.7; P = 0.047). Middle ear polyps were associated with 8.8 times the odds of presenting with Horner syndrome (95% CI 1.5-50.0; P = 0.015). CONCLUSIONS AND RELEVANCE Although it may be difficult to identify the underlying diagnosis in cats with vestibular syndrome from the presenting features alone, there are instances in which discrete clinical features may help to guide clinical reasoning when evaluating cats with vestibular presentations.
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Affiliation(s)
- Nicholas J Grapes
- Department of Clinical Science and Services, Royal Veterinary College, North Mymms, Hatfield, UK
| | | | - Holger A Volk
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
| | - Steven De Decker
- Department of Clinical Science and Services, Royal Veterinary College, North Mymms, Hatfield, UK
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Diagnostic Value of Detecting Feline Coronavirus RNA and Spike Gene Mutations in Cerebrospinal Fluid to Confirm Feline Infectious Peritonitis. Viruses 2021; 13:v13020186. [PMID: 33513683 PMCID: PMC7912268 DOI: 10.3390/v13020186] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 01/15/2021] [Accepted: 01/21/2021] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Cats with neurologic feline infectious peritonitis (FIP) are difficult to diagnose. Aim of this study was to evaluate the diagnostic value of detecting feline coronavirus (FCoV) RNA and spike (S) gene mutations in cerebrospinal fluid (CSF). METHODS The study included 30 cats with confirmed FIP (six with neurological signs) and 29 control cats (eleven with neurological signs) with other diseases resulting in similar clinical signs. CSF was tested for FCoV RNA by 7b-RT-qPCR in all cats. In RT-qPCR-positive cases, S-RT-qPCR was additionally performed to identify spike gene mutations. RESULTS Nine cats with FIP (9/30, 30%), but none of the control cats were positive for FCoV RNA in CSF. Sensitivity of 7b-RT-qPCR in CSF was higher for cats with neurological FIP (83.3%; 95% confidence interval (95% CI) 41.8-98.9) than for cats with non-neurological FIP (16.7%; 95% CI 6.1-36.5). Spike gene mutations were rarely detected. CONCLUSIONS FCoV RNA was frequently present in CSF of cats with neurological FIP, but only rarely in cats with non-neurological FIP. Screening for spike gene mutations did not enhance specificity in this patient group. Larger populations of cats with neurological FIP should be explored in future studies.
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Gholami M, Safari S, Ulloa L, Motaghinejad M. Neuropathies and neurological dysfunction induced by coronaviruses. J Neurovirol 2021; 27:380-396. [PMID: 33983506 PMCID: PMC8117458 DOI: 10.1007/s13365-021-00977-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 01/23/2021] [Accepted: 04/05/2021] [Indexed: 02/03/2023]
Abstract
During the recent years, viral epidemic due to coronaviruses, such as SARS (Severe Acute Respiratory Syndrome), Middle East Respiratory Coronavirus Syndrome (MERS), and COVID-19 (coronavirus disese-19), has become a global problem. In addition to causing cardiovascular and respiratory lethal dysfunction, these viruses can cause neurodegeneration leading to neurological disorders. Review of the current scientific literature reveals the multiple neuropathies and neuronal dysfunction associated with these viruses. Here, we review the major findings of these studies and discuss the main neurological sequels and outcomes of coronavirus infections with SARS, MERS, and COVID-19. This article analyzes and discusses the main mechanisms of coronavirus-induced neurodegeneration according to the current experimental and clinical studies. Coronaviruses can damage the nerves directly through endovascular dysfunctions thereby affecting nerve structures and synaptic connections. Coronaviruses can also induce neural cell degeneration indirectly via mitochondrial dysfunction inducing oxidative stress, inflammation, and apoptosis. Thus, coronaviruses can cause neurological disorders by inducing neurovascular dysfunction affecting nerve structures and synaptic connections, and by inducing inflammation, oxidative stress, and apoptosis. While some of these mechanisms are similar to other RNA viruses, the neurotoxic mechanisms of COVID-19, MERS, and SARS-CoV viruses are unknown and need detailed clinical and experimental studies.
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Affiliation(s)
- Mina Gholami
- Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
| | - Sepideh Safari
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Luis Ulloa
- Center for Perioperative Organ Protection, Department of Anesthesiology, Duke University, NC, 27710, Durham, USA.
| | - Majid Motaghinejad
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran.
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Hoey C, Nye G, Fadda A, Bradshaw J, Barker EN. Subarachnoid diverticulum associated with feline infectious peritonitis in a Siberian cat. JFMS Open Rep 2020; 6:2055116920941477. [PMID: 33149927 PMCID: PMC7580156 DOI: 10.1177/2055116920941477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Case summary A 7-month-old Siberian cat was presented for investigation of acute onset multifocal neurological deficits. Neurological examination documented dull mental status and an ambulatory left hemiparesis. Serum biochemistry documented marked hyperglobulinaemia. MRI of the brain identified marked leptomeningeal contrast enhancement extending along the brainstem caudally to involve the cranial cervical spinal cord. MRI of the cervical spine further identified a subarachnoid diverticulum that extended from the level of the obex to the C2-C3 vertebrae. Cerebrospinal fluid quantitative RT-PCR was positive for the presence of feline coronavirus. Histopathology revealed pyogranulomatous meningitis and choroid plexitis, uveitis and nephritis. Relevance and novel information This article describes the first reported case of a subarachnoid diverticulum associated with feline infectious peritonitis.
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Affiliation(s)
- Christopher Hoey
- Bristol Veterinary School, University of Bristol, Langford, Bristol, UK
| | - George Nye
- Bristol Veterinary School, University of Bristol, Langford, Bristol, UK
| | | | - Janet Bradshaw
- Bristol Veterinary School, University of Bristol, Langford, Bristol, UK
| | - Emi N Barker
- Bristol Veterinary School, University of Bristol, Langford, Bristol, UK.,The Feline Centre, Langford Vets, Langford, Bristol, UK
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Hu X, Xiao L, Cong X, Zhu Y, Huang B, Cong F. Development of a recombinase polymerase amplification fluorescence assay to detect feline coronavirus. Mol Cell Probes 2020; 54:101669. [PMID: 33203619 PMCID: PMC7581357 DOI: 10.1016/j.mcp.2020.101669] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/21/2020] [Accepted: 10/14/2020] [Indexed: 11/27/2022]
Abstract
Feline coronavirus (FCoV) is classified into two pathotypes: the avirulent feline enteric coronavirus (FECV), and the virulent feline infectious peritonitis virus (FIPV). Rapid pathogen detection, which is efficient and convenient, is the best approach for early confirmatory diagnosis. In this study, we first developed and evaluated a rapid recombinase polymerase amplification (RPA) detection method for FCoV that can detect FCoV within 15 min at 39 °C. The detection limit of that assay was 233 copies/μL DNA molecules per reaction. The specificity was high: it did not cross-react with canine distemper virus (CDV), canine coronavirus (CCoV), canine adenovirus (CAV), feline calicivirus (FCV), feline herpesvirus (FHV), or feline parvovirus (FPV). This assay was evaluated using 42 clinical samples (30 diarrhea samples and 12 ascites samples). The coincidence rate between FCoV-RPA and RT-qPCR for detection in clinical samples was 95.2%. In summary, FCoV-RPA analysis provides an efficient, rapid, and sensitive detection method for FCoV. FCoV RPA has the shortest reaction time within 15 min among all the PCR-based methods. FCoV RPA detection method has no cross-reactivity with other pathogens. The sensitivity of FCoV RPA was consistent with real-time PCR, as low as 204 copies/μL of DNA molecules per reaction.
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Affiliation(s)
- Xiaoliang Hu
- School of Life Sciences and Food Engineering, Yibin University, Yibin Key Laboratory of Zoological Diversity and Ecological Conservation, Yibin, 644000, China.
| | - Li Xiao
- Guangdong Laboratory Animals Monitoring Institute and Guangdong Provincial Key Laboratory of Laboratory Animals, Guangzhou, 510633, China.
| | - Xiao Cong
- Anhui Science and Technology University, Chuzhou, 233100, China.
| | - Yujun Zhu
- Guangdong Laboratory Animals Monitoring Institute and Guangdong Provincial Key Laboratory of Laboratory Animals, Guangzhou, 510633, China.
| | - Bihong Huang
- Guangdong Laboratory Animals Monitoring Institute and Guangdong Provincial Key Laboratory of Laboratory Animals, Guangzhou, 510633, China.
| | - Feng Cong
- Guangdong Laboratory Animals Monitoring Institute and Guangdong Provincial Key Laboratory of Laboratory Animals, Guangzhou, 510633, China.
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Sangl L, Felten S, Matiasek K, Dörfelt S, Bergmann M, Balzer HJ, Pantchev N, Leutenegger C, Hartmann K. Detection of feline coronavirus RNA, spike gene mutations, and feline coronavirus antigen in macrophages in aqueous humor of cats in the diagnosis of feline infectious peritonitis. J Vet Diagn Invest 2020; 32:527-534. [PMID: 32517543 PMCID: PMC7438658 DOI: 10.1177/1040638720927362] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Uveitis is common in cats, and is often a feature of feline infectious peritonitis (FIP). We evaluated 3 tools for detection of feline coronavirus (FCoV) in aqueous humor: 1) a 7b gene reverse-transcription real-time PCR (7b-RT-rtPCR) assay to detect FCoV RNA, 2) a spike gene mutation RT-rtPCR (S-RT-rtPCR) assay to detect 2 point mutations in the spike gene of FCoV in cats positive by 7b-RT-rtPCR, and 3) immunocytochemistry (ICC) for detection of FCoV antigen in aqueous humor macrophages. We studied 58 cats, including 31 cats with FIP and 27 control cats. FIP was excluded by postmortem examination and negative immunohistochemistry (IHC). Aqueous humor samples obtained postmortem were assessed using 7b-RT-rtPCR in all cats, and positive samples were evaluated with S-RT-rtPCR. ICC evaluation of aqueous humor samples from 36 of the 58 cats was done using an avidin-biotin complex method and monoclonal anti-FCoV IgG 2A. Sensitivity, specificity, and negative and positive predictive values were calculated including 95% CIs. 7b-RT-rtPCR had a specificity of 100.0% (95% CI: 87.2-100.0) and sensitivity of 35.5% (95% CI: 19.2-54.6). Specificity of S-RT-rtPCR could not be determined because there were no FCoV 7b-RT-rtPCR-positive samples in the control group. Sensitivity of S-RT-rtPCR was 12.9% (95% CI 3.6-29.8). Sensitivity and specificity of ICC were 62.5% (95% CI: 40.6-81.2) and 80.0% (95% CI: 44.4-97.5), respectively. The combination of 7b-RT-rtPCR and IHC could be useful in diagnosing FIP; S-RT-rtPCR did not add value; and ICC of aqueous humor samples cannot be recommended for the diagnosis of FIP.
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Affiliation(s)
- Laura Sangl
- Laura Sangl, Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Veterinaerstrasse 13, Munich, Bayern, 80539, Germany.
| | - Sandra Felten
- Clinic of Small Animal Medicine (Sangl, Hartmann, Dörfelt, Felten, Bergmann) and Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology (Matiasek), Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Munich, Bayern, Germany
- Idexx Laboratories, Ludwigsburg, Germany (Balzer, Pantchev) and West Sacramento, CA (Leutenegger)
| | - Kaspar Matiasek
- Clinic of Small Animal Medicine (Sangl, Hartmann, Dörfelt, Felten, Bergmann) and Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology (Matiasek), Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Munich, Bayern, Germany
- Idexx Laboratories, Ludwigsburg, Germany (Balzer, Pantchev) and West Sacramento, CA (Leutenegger)
| | - Stefanie Dörfelt
- Clinic of Small Animal Medicine (Sangl, Hartmann, Dörfelt, Felten, Bergmann) and Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology (Matiasek), Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Munich, Bayern, Germany
- Idexx Laboratories, Ludwigsburg, Germany (Balzer, Pantchev) and West Sacramento, CA (Leutenegger)
| | - Michele Bergmann
- Clinic of Small Animal Medicine (Sangl, Hartmann, Dörfelt, Felten, Bergmann) and Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology (Matiasek), Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Munich, Bayern, Germany
- Idexx Laboratories, Ludwigsburg, Germany (Balzer, Pantchev) and West Sacramento, CA (Leutenegger)
| | - Hans-Jörg Balzer
- Clinic of Small Animal Medicine (Sangl, Hartmann, Dörfelt, Felten, Bergmann) and Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology (Matiasek), Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Munich, Bayern, Germany
- Idexx Laboratories, Ludwigsburg, Germany (Balzer, Pantchev) and West Sacramento, CA (Leutenegger)
| | - Nikola Pantchev
- Clinic of Small Animal Medicine (Sangl, Hartmann, Dörfelt, Felten, Bergmann) and Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology (Matiasek), Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Munich, Bayern, Germany
- Idexx Laboratories, Ludwigsburg, Germany (Balzer, Pantchev) and West Sacramento, CA (Leutenegger)
| | - Christian Leutenegger
- Clinic of Small Animal Medicine (Sangl, Hartmann, Dörfelt, Felten, Bergmann) and Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology (Matiasek), Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Munich, Bayern, Germany
- Idexx Laboratories, Ludwigsburg, Germany (Balzer, Pantchev) and West Sacramento, CA (Leutenegger)
| | - Katrin Hartmann
- Clinic of Small Animal Medicine (Sangl, Hartmann, Dörfelt, Felten, Bergmann) and Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology (Matiasek), Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Munich, Munich, Bayern, Germany
- Idexx Laboratories, Ludwigsburg, Germany (Balzer, Pantchev) and West Sacramento, CA (Leutenegger)
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13
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Mella SL, Cardy TJA, Volk HA, De Decker S. Clinical reasoning in feline spinal disease: which combination of clinical information is useful? J Feline Med Surg 2020; 22:521-530. [PMID: 31251096 PMCID: PMC10814331 DOI: 10.1177/1098612x19858447] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES The aim of this study was to evaluate if a combination of discrete clinical characteristics can be used to identify the most likely differential diagnoses in cats with spinal disease. METHODS Two hundred and twenty-one cats referred for further evaluation of spinal disease were included and categorised as follows: non-lymphoid neoplasia (n = 44); intervertebral disc disease (n = 42); fracture/luxation (n = 34); ischaemic myelopathy (n = 22); feline infectious peritonitis virus myelitis (n = 18); lymphoma (n = 16); thoracic vertebral canal stenosis (n = 11); acute non-compressive nucleus pulposus extrusion (n = 11); traumatic spinal cord contusion (n = 8); spinal arachnoid diverticula (n = 7); lumbosacral stenosis (n = 5); and spinal empyema (n = 3). Information retrieved from the medical records included signalment, clinical history and clinical presentation. Univariate analyses of variables (clinical history, breed, age, sex, general physical examination findings, onset, progression, spinal hyperaesthesia, asymmetry, ambulatory status and neuroanatomical location) were performed, and variables were retained in a multivariate logistic regression model if P <0.05. RESULTS Multivariate logistic regression revealed that intervertebral disc disease most often occurred in middle-aged, purebred cats with a normal general physical examination and an acute onset of painful and progressive clinical signs. Ischaemic myelopathy occurred most often in older cats with a stable or improving, non-painful, lateralising, C6-T2 myelopathy. Spinal fracture/luxation occurred most often in younger cats and resulted most often in a peracute onset, painful, non-ambulatory neurological status. Concurrent systemic abnormalities or abnormal findings detected on general physical examination were significantly associated with feline infectious peritonitis virus myelitis, spinal lymphoma or spinal empyema. CONCLUSIONS AND RELEVANCE This study suggests that using easily identifiable characteristics from the history and clinical examination can assist in obtaining a preliminary differential diagnosis when evaluating cats with spinal disease. This information could aid veterinary practitioners in clinical decision-making.
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Affiliation(s)
- Stephanie L Mella
- Clinical Science and Services, The Royal Veterinary College, University of London, Hatfield, UK
| | - Thomas JA Cardy
- Clinical Science and Services, The Royal Veterinary College, University of London, Hatfield, UK
- Cave Veterinary Specialists, West Buckland, Wellington, UK
| | - Holger A Volk
- Clinical Science and Services, The Royal Veterinary College, University of London, Hatfield, UK
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Steven De Decker
- Clinical Science and Services, The Royal Veterinary College, University of London, Hatfield, UK
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14
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Felten S, Hartmann K. Diagnosis of Feline Infectious Peritonitis: A Review of the Current Literature. Viruses 2019; 11:v11111068. [PMID: 31731711 PMCID: PMC6893704 DOI: 10.3390/v11111068] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 11/10/2019] [Accepted: 11/13/2019] [Indexed: 12/12/2022] Open
Abstract
Feline infectious peritonitis (FIP) is a fatal disease that poses several challenges for veterinarians: clinical signs and laboratory changes are non-specific, and there are two pathotypes of the etiologic agent feline coronavirus (FCoV), sometimes referred to as feline enteric coronavirus (FECV) and feline infectious peritonitis virus (FIPV) that vary fundamentally in their virulence, but are indistinguishable by a number of diagnostic methods. This review focuses on all important steps every veterinary practitioner has to deal with and new diagnostic tests that can be considered when encountering a cat with suspected FIP with the aim to establish a definitive diagnosis. It gives an overview on all available direct and indirect diagnostic tests and their sensitivity and specificity reported in the literature in different sample material. By providing summarized data for sensitivity and specificity of each diagnostic test and each sample material, which can easily be accessed in tables, this review can help to facilitate the interpretation of different diagnostic tests and raise awareness of their advantages and limitations. Additionally, diagnostic trees depict recommended diagnostic steps that should be performed in cats suspected of having FIP based on their clinical signs or clinicopathologic abnormalities. These steps can easily be followed in clinical practice.
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15
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Emmler L, Felten S, Matiasek K, Balzer HJ, Pantchev N, Leutenegger C, Hartmann K. Feline coronavirus with and without spike gene mutations detected by real-time RT-PCRs in cats with feline infectious peritonitis. J Feline Med Surg 2019; 22:791-799. [PMID: 31729897 PMCID: PMC7206566 DOI: 10.1177/1098612x19886671] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVES Feline infectious peritonitis (FIP) emerges when feline coronaviruses (FCoVs) mutate within their host to a highly virulent biotype and the immune response is not able to control the infection. FCoV spike (S) gene mutations are considered to contribute to the change in virulence by enabling FCoV infection of and replication in macrophages. This study investigated the presence of FCoV with and without S gene mutations in cats with FIP using two different real-time RT-PCRs on different samples obtained under clinical conditions. METHODS Fine-needle aspirates (FNAs) and incisional biopsies (IBs) of popliteal and mesenteric lymph nodes, liver, spleen, omentum and kidneys (each n = 20), EDTA blood (n = 13), buffy coat smears (n = 13), serum (n = 11), effusion (n = 14), cerebrospinal fluid (n = 16), aqueous humour (n = 20) and peritoneal lavage (n = 6) were obtained from 20 cats with FIP diagnosed by immunohistochemistry. Samples were examined by RT-PCR targeting the FCoV 7b gene, detecting all FCoV, and S gene mutation RT-PCR targeting mutations in nucleotides 23531 and 23537. The prevalence of FCoV detected in each sample type was calculated. RESULTS In 20/20 cats, FCoV with S gene mutations was present in at least one sample, but there was variation in which sample was positive. FCoV with mutations in the S gene was most frequently found in effusion (64%, 95% confidence interval [CI] 39-89), followed by spleen, omentum and kidney IBs (50%, 95% CI 28-72), mesenteric lymph node IBs and FNAs (45%, 95% CI 23-67), and FNAs of spleen and liver and liver IBs (40%, 95% CI 19-62). CONCLUSIONS AND RELEVANCE In these 20 cats with FIP, FCoVs with S gene mutations were found in every cat in at least one tissue or fluid sample. This highlights the association between mutated S gene and systemic FCoV spread. Examining a combination of different samples increased the probability of finding FCoV with the mutated S gene.
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Affiliation(s)
- Laura Emmler
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University of Munich, Munich, Germany
| | - Sandra Felten
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University of Munich, Munich, Germany
| | - Kaspar Matiasek
- Section of Clinical and Comparative Neuropathology, Institute of Veterinary Pathology, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University of Munich, Munich, Germany
| | | | | | | | - Katrin Hartmann
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University of Munich, Munich, Germany
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16
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Stranieri A, Probo M, Pisu MC, Fioletti A, Meazzi S, Gelain ME, Bonsembiante F, Lauzi S, Paltrinieri S. Preliminary investigation on feline coronavirus presence in the reproductive tract of the tom cat as a potential route of viral transmission. J Feline Med Surg 2019; 22:178-185. [PMID: 30900940 PMCID: PMC7221457 DOI: 10.1177/1098612x19837114] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Objectives Feline infectious peritonitis (FIP) is an immune-mediated disease initiated
by feline coronavirus (FCoV) infection. To date, the only proven route of
transmission is the faecal–oral route, but a possible localisation of FCoV
in the reproductive tract of tom cats is of concern, owing to the
involvement of the male reproductive tract during FIP and to the presence of
reproduction disorders in FCoV-endemic feline catteries. The aim of the
study was to investigate the presence and localisation of FCoV in semen
and/or in the reproductive tract of tom cats, and its possible association
with seroconversion and viraemic phase. Methods Blood, serum, semen and/or testicle samples were obtained from 46 tom cats.
Serology was performed on 38 serum samples, nested reverse transcriptase PCR
(nRT-PCR) and reverse transcriptase quantitative PCR (RT-qPCR) were
performed on 39 blood samples and on 17 semen samples, and histology,
immunohistochemistry and nRT-PCR were performed on 39 testicles. Results Twenty-four of 38 serum samples were positive on serology. Semen samples were
negative on RT-PCR and RT-qPCR for FCoV, while all blood samples were
negative at both molecular methods, except for one sample positive at
RT-qPCR with a very low viral load. All testicles were negative at
immunohistochemistry, while six were positive at nRT-PCR for FCoV. Serology
and blood PCR results suggest that the virus was present in the environment,
stimulating transient seroconversion. FCoV seems not to localise in the
semen of tom cats, making the venereal route as a way of transmission
unlikely. Although viral RNA was found in some testicles, it could not be
correlated with the viraemic phase. Conclusions and relevance In the light of these preliminary results, artificial insemination appears
safer than natural mating as it eliminates the direct contact between
animals, thus diminishing the probability of faecal–oral FCoV
transmission.
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Affiliation(s)
- Angelica Stranieri
- Department of Veterinary Medicine, University of Milan, Milan, Italy.,Central Laboratory, Veterinary Teaching Hospital, University of Milan, Lodi, Italy
| | - Monica Probo
- Department of Veterinary Medicine, University of Milan, Milan, Italy
| | | | - Alberto Fioletti
- Department of Veterinary Medicine, University of Milan, Milan, Italy
| | - Sara Meazzi
- Department of Veterinary Medicine, University of Milan, Milan, Italy.,Central Laboratory, Veterinary Teaching Hospital, University of Milan, Lodi, Italy
| | - Maria E Gelain
- Department of Comparative Biomedicine and Food Science, University of Padova, Legnaro, Padova, Italy
| | - Federico Bonsembiante
- Department of Comparative Biomedicine and Food Science, University of Padova, Legnaro, Padova, Italy
| | - Stefania Lauzi
- Department of Veterinary Medicine, University of Milan, Milan, Italy.,Central Laboratory, Veterinary Teaching Hospital, University of Milan, Lodi, Italy
| | - Saverio Paltrinieri
- Department of Veterinary Medicine, University of Milan, Milan, Italy.,Central Laboratory, Veterinary Teaching Hospital, University of Milan, Lodi, Italy
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17
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Sangl L, Matiasek K, Felten S, Gründl S, Bergmann M, Balzer HJ, Pantchev N, Leutenegger CM, Hartmann K. Detection of feline coronavirus mutations in paraffin-embedded tissues in cats with feline infectious peritonitis and controls. J Feline Med Surg 2019; 21:133-142. [PMID: 29542369 PMCID: PMC10814605 DOI: 10.1177/1098612x18762883] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES The amino acid substitutions M1058L and S1060A in the spike protein of feline coronavirus (FCoV) have been postulated to be responsible for the development of the pathogenic feline infectious peritonitis virus (FIPV), which causes feline infectious peritonitis (FIP). The aim of the following study was to investigate the presence of mutated virus in tissue samples of cats with and without FIP. METHODS The study population consisted of 64 cats, 34 of which were diagnosed with FIP and 30 control cats. All cases underwent autopsy, histopathology and immunohistochemistry (IHC) for FCoV. Furthermore, a genotype-discriminating quantitative reverse transcriptase PCR (RT-qPCR) was performed on shavings of paraffin-embedded tissues to discriminate between cats with FIP and controls, and the sensitivity and specificity of this discriminating RT-qPCR were calculated using 95% confidence intervals (CIs). RESULTS Specificity of genotype-discriminating RT-qPCR was 100.0% (95% CI 88.4-100.0), and sensitivity was 70.6% (95% CI 52.5-84.9). In cats with FIP, 24/34 tested positive for FIPV. In samples of three control cats and in seven cats with FIP, FCoV was found, but genotyping was not possible owing to low FCoV RNA concentrations. Out of the positive samples, 23 showed the amino acid substitution M1058L in the spike protein and none the substitution S1060A. One sample in a cat with FIP revealed a mixed population of non-mutated FCoV and FIPV (mixed genotype). For one sample genotyping was not possible despite high viral load, and two samples were negative for FCoV. CONCLUSIONS AND RELEVANCE As none of the control animals showed FCoV amino acid substitutions previously demonstrated in cats with FIP, it can be presumed that the substitution M1058L correlates with the presence of FIP. FCoV was detected in low concentration in tissues of control animals, confirming the ability of FCoV to spread systemically. The fact that no negative controls were included in the IHC protocol could potentially lead to an underestimation of the sensitivity of the RT-qPCR.
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Affiliation(s)
- Laura Sangl
- Clinic of Small Animal Medicine, LMU, Munich, Germany
| | - Kaspar Matiasek
- Section of Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, LMU, Munich, Germany
| | - Sandra Felten
- Clinic of Small Animal Medicine, LMU, Munich, Germany
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18
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Tasker S. Diagnosis of feline infectious peritonitis: Update on evidence supporting available tests. J Feline Med Surg 2018; 20:228-243. [PMID: 29478397 PMCID: PMC10816288 DOI: 10.1177/1098612x18758592] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Practical relevance: Feline coronavirus (FCoV) infection is very common in cats, usually causing only mild intestinal signs such as diarrhoea. Up to 10% of FCoV infections, however, result in the fatal disease feline infectious peritonitis (FIP). Clinical challenges: Obtaining a definitive diagnosis of FIP based on non-invasive approaches is difficult. Confirmation of the disease relies on finding appropriate cytological or histopathological changes in association with positive immunostaining for FCoV antigen. In FIP cases with effusions, cytology and immunostaining on effusion samples can be relatively easy to perform; otherwise obtaining diagnostic samples is more challenging and collection of biopsies from tissues with gross lesions is necessary. In the absence of a definitive diagnosis, a high index of suspicion of FIP may be obtained from the cat's signalment and history, combined with findings on clinical examination and laboratory test results. If largely consistent with FIP, these can be used as a basis for discussion with the owner about whether additional, more invasive, diagnostic tests are warranted. In some cases it may be that euthanasia is discussed as an alternative to pursuing a definitive diagnosis ante-mortem, especially if financial limitations exist or where there are concerns over a cat's ability to tolerate invasive diagnostic procedures. Ideally, the diagnosis should be confirmed in such patients from samples taken at post-mortem examination. Global importance: FIP occurs wherever FCoV infection is present in cats, which equates to most parts of the world. Evidence base: This review provides a comprehensive overview of how to approach the diagnosis of FIP, focusing on the tests available to the veterinary practitioner and recently published evidence supporting their use.
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Affiliation(s)
- Séverine Tasker
- The Feline Centre, Langford Vets, Bristol Veterinary School, University of Bristol, Bristol, BS40 5DU, UK
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19
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Rissi DR. A retrospective study of the neuropathology and diagnosis of naturally occurring feline infectious peritonitis. J Vet Diagn Invest 2018; 30:392-399. [PMID: 29411701 DOI: 10.1177/1040638718755833] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Feline infectious peritonitis (FIP) is one of the most important viral diseases of cats worldwide. Our study describes the neuropathology and the diagnostic features of 26 cases of FIP in domestic cats. The average age of affected individuals was 11.8 mo, and there was no sex or breed predisposition. Clinical neurologic signs were noted in 22 cases, and rabies was clinically suspected in 11 cases. Twenty cats had lesions in multiple organs, and 6 cats had lesions only in the brain. Gross neuropathologic changes occurred in 15 cases and consisted of hydrocephalus (10 cases), cerebellar herniation through the foramen magnum (6 cases), cerebral swelling with flattening of gyri (2 cases), and accumulation of fibrin within ventricles (2 cases) or leptomeninges (1 case). Histologically, 3 main distinct distributions of neuropathologic changes were observed, namely periventricular encephalitis (12 cases), rhombencephalitis (8 cases), and diffuse leptomeningitis with superficial encephalitis (6 cases). Fresh tissue samples were submitted for fluorescent antibody testing (FAT) after autopsy in 17 cases, and positive results were found in only 7 cases. Immunohistochemistry (IHC) for feline coronavirus confirmed the diagnosis in all 26 cases. IHC appears to be a more sensitive and reliable test for confirmation of FIP than is FAT.
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Affiliation(s)
- Daniel R Rissi
- Department of Pathology and Athens Veterinary Diagnostic Laboratory, College of Veterinary Medicine, The University of Georgia, Athens, GA
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20
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Soma T, Saito N, Kawaguchi M, Sasai K. Feline coronavirus antibody titer in cerebrospinal fluid from cats with neurological signs. J Vet Med Sci 2017; 80:59-62. [PMID: 29118313 PMCID: PMC5797860 DOI: 10.1292/jvms.17-0399] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
To investigate the utility of cerebrospinal fluid (CSF) anti-feline coronavirus (FCoV) antibody test for diagnosis of feline infectious peritonitis (FIP), the antibody titers were tested in CSF and sera from 271 FIP-suspected neurological cats. CSF antibody was detected in 28 cats, which were divided into 2 groups; 15 with CSF titer of 1:80 or lower and 13 with CSF titer of 1:640 or higher. In the latter group, reciprocal serum titer/reciprocal CSF titer was 8 or lower, which is extremely lower than normal range (256-2048), and FCoV RNA was detected in all of 11 CSF samples assayed by RT-PCR. Our findings indicate that CSF titer of 1:640 or higher may be served as a candidate for the index for diagnosing FIP.
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Affiliation(s)
- Takehisa Soma
- Veterinary Diagnostic Laboratory, Marupi Lifetech Co., Ltd., 103 Fushiocho, Ikeda, Osaka 563-0011, Japan.,Laboratory of Veterinary Internal Medicine, Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Orai-Kita, Izumisano, Osaka 598-8531, Japan
| | - Namiko Saito
- Veterinary Diagnostic Laboratory, Marupi Lifetech Co., Ltd., 103 Fushiocho, Ikeda, Osaka 563-0011, Japan
| | - Masato Kawaguchi
- Veterinary Diagnostic Laboratory, Marupi Lifetech Co., Ltd., 103 Fushiocho, Ikeda, Osaka 563-0011, Japan
| | - Kazumi Sasai
- Laboratory of Veterinary Internal Medicine, Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Orai-Kita, Izumisano, Osaka 598-8531, Japan
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21
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Lorusso E, Mari V, Losurdo M, Lanave G, Trotta A, Dowgier G, Colaianni ML, Zatelli A, Elia G, Buonavoglia D, Decaro N. Discrepancies between feline coronavirus antibody and nucleic acid detection in effusions of cats with suspected feline infectious peritonitis. Res Vet Sci 2017; 125:421-424. [PMID: 29113645 PMCID: PMC7111774 DOI: 10.1016/j.rvsc.2017.10.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 10/17/2017] [Accepted: 10/28/2017] [Indexed: 12/02/2022]
Abstract
Intra-vitam diagnosis of feline infectious peritonitis (FIP) is a challenge for veterinary diagnosticians, since there are no highly specific and sensitive assays currently available. With the aim to contribute to fill this diagnostic gap, a total of 61 effusions from cats with suspected effusive FIP were collected intra-vitam for detection of feline coronavirus (FCoV) antibodies and RNA by means of indirect immunofluorescence (IIF) assay and real-time RT-PCR (qRT-PCR), respectively. In 5 effusions there was no evidence for either FCoV RNA or antibodies, 51 and 52 specimens tested positive by IIF and qRT-PCR, respectively, although antibody titres ≥ 1:1600, which are considered highly suggestive of FIP, were detected only in 37 effusions. Three samples with high antibody levels tested negative by qRT-PCR, whereas 18 qRT-PCR positive effusions contained no or low-titre antibodies. qRT-PCR positive samples with low antibody titres mostly contained low FCoV RNA loads, although the highest antibody titres were detected in effusions with CT values > 30. In conclusion, combining the two methods, i.e., antibody and RNA detection would help improving the intra-vitam diagnosis of effusive FIP. Effusions from cats with suspected FIP were analysed for detection of feline coronavirus (FCoV) antibodies and RNA. Using a cut-off of 1:1600 for FCoV antibodies, only 40/61 samples were in agreement between the two tests. Most effusions with low FCoV loads were found to contain low specific antibody titres. Combining serological and molecular methods results in an increase of the diagnostic efficiency.
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Affiliation(s)
- Eleonora Lorusso
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy
| | - Viviana Mari
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy
| | - Michele Losurdo
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy
| | - Gianvito Lanave
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy
| | - Adriana Trotta
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy
| | - Giulia Dowgier
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy
| | - Maria Loredana Colaianni
- Istituto Zooprofilattico Sperimentale di Puglia e Basilicata, via Manfredonia 20, 71121 Foggia, Italy
| | - Andrea Zatelli
- Medical Consultancy Services, 60, Suite 6, G Cali Street, XBX 1424 Ta' Xbiex, Malta
| | - Gabriella Elia
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy
| | - Domenico Buonavoglia
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy
| | - Nicola Decaro
- Department of Veterinary Medicine, University of Bari, Strada per Casamassima Km 3, Valenzano, Bari 70010, Italy.
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22
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Barker EN, Stranieri A, Helps CR, Porter EL, Davidson AD, Day MJ, Knowles T, Kipar A, Tasker S. Limitations of using feline coronavirus spike protein gene mutations to diagnose feline infectious peritonitis. Vet Res 2017; 48:60. [PMID: 28982390 PMCID: PMC5629788 DOI: 10.1186/s13567-017-0467-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 09/15/2017] [Indexed: 12/23/2022] Open
Abstract
Feline infectious peritonitis (FIP) is a fatal disease of cats, and a sequela of systemic feline coronavirus (FCoV) infection. Mutations in the viral spike (S) gene have been associated with FCoVs found in tissues from cats with FIP, but not FCoVs found in faeces from healthy cats, and are implicated in monocyte/macrophage tropism and systemic spread. This study was designed to determine whether S gene mutation analysis can reliably diagnose FIP. Cats were categorised as with FIP (n = 57) or without FIP (n = 45) based on gross post-mortem and histopathological examination including immunohistochemistry for FCoV antigen. RNA was purified from available tissue, fluid and faeces. Reverse-transcriptase quantitative-PCR (RT-qPCR) was performed on all samples using FCoV-specific primers, followed by sequencing of a section of the S gene on RT-qPCR positive samples. Samples were available from a total of 102 cats. Tissue, fluid, and faecal samples from cats with FIP were more likely to be FCoV RT-qPCR-positive (90.4, 78.4 and 64.6% respectively) than those from cats without FIP (7.8, 2.1 and 20% respectively). Identification of S gene mutated FCoVs as an additional step to the detection of FCoV alone, only moderately increased specificity for tissue samples (from 92.6 to 94.6%) but specificity was unchanged for fluid samples (97.9%) for FIP diagnosis; however, sensitivity was markedly decreased for tissue (from 89.8 to 80.9%) and fluid samples (from 78.4 to 60%) for FIP diagnosis. These findings demonstrate that S gene mutation analysis in FCoVs does not substantially improve the ability to diagnose FIP as compared to detection of FCoV alone.
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Affiliation(s)
- Emily N Barker
- School of Veterinary Sciences, University of Bristol, Bristol, UK.
| | | | - Chris R Helps
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - Emily L Porter
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - Andrew D Davidson
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, UK
| | - Michael J Day
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - Toby Knowles
- School of Veterinary Sciences, University of Bristol, Bristol, UK
| | - Anja Kipar
- Institute of Veterinary Pathology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.,Institute of Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK
| | - Séverine Tasker
- School of Veterinary Sciences, University of Bristol, Bristol, UK
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23
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Sensitivity and specificity of a real-time reverse transcriptase polymerase chain reaction detecting feline coronavirus mutations in effusion and serum/plasma of cats to diagnose feline infectious peritonitis. BMC Vet Res 2017; 13:228. [PMID: 28768514 PMCID: PMC5541694 DOI: 10.1186/s12917-017-1147-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2016] [Accepted: 07/24/2017] [Indexed: 12/11/2022] Open
Abstract
Background Feline coronavirus (FCoV) exists as two pathotypes, and FCoV spike gene mutations are considered responsible for the pathotypic switch in feline infectious peritonitis (FIP) pathogenesis. The aim of this study was to evaluate sensitivity and specificity of a real-time reverse transcriptase polymerase chain reaction (RT-PCR) specifically designed to detect FCoV spike gene mutations at two nucleotide positions. It was hypothesized that this test would correctly discriminate feline infectious peritonitis virus (FIPV) and feline enteric coronavirus (FECV). Methods The study included 63 cats with signs consistent with FIP. FIP was confirmed in 38 cats. Twenty-five control cats were definitively diagnosed with a disease other than FIP. Effusion and/or serum/plasma samples were examined by real-time RT-PCR targeting the two FCoV spike gene fusion peptide mutations M1058 L and S1060A using an allelic discrimination approach. Sensitivity, specificity, negative and positive predictive values including 95% confidence intervals (95% CI) were calculated. Results FIPV was detected in the effusion of 25/59 cats, one of them being a control cat with chronic kidney disease. A mixed population of FIPV/FECV was detected in the effusion of 2/59 cats; all of them had FIP. RT-PCR was negative or the pathotype could not be determined in 34/59 effusion samples. In effusion, sensitivity was 68.6% (95% CI 50.7–83.2), specificity was 95.8% (95% CI 78.9–99.9). No serum/plasma samples were positive for FIPV. Conclusions Although specificity of the test in effusions was high, one false positive result occurred. The use of serum/plasma cannot be recommended due to a low viral load in blood.
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Gruendl S, Matiasek K, Matiasek L, Fischer A, Felten S, Jurina K, Hartmann K. Diagnostic utility of cerebrospinal fluid immunocytochemistry for diagnosis of feline infectious peritonitis manifesting in the central nervous system. J Feline Med Surg 2017; 19:576-585. [PMID: 27095828 PMCID: PMC11128807 DOI: 10.1177/1098612x16640839] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Objectives The aim of the study was to evaluate whether an ante-mortem diagnosis of central nervous system (CNS) feline infectious peritonitis (FIP) is possible via immunocytochemical staining (ICC) of feline coronavirus antigen (FCoV) within macrophages of cerebrospinal fluid (CSF). Methods Prospectively, CSF samples of 41 cats were investigated, including cats with histopathologically confirmed FIP and neurological signs (n = 10), cats with confirmed FIP without CNS involvement (n = 11), cats with neurological signs but another confirmed CNS disease (n = 17), and cats without neurological signs and a disease other than FIP (n = 3). ICC staining of CSF macrophages was performed in all cats. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of CSF ICC were calculated. Results Of 10 samples from cats with CNS FIP, eight had detectable CSF macrophages, seven of which were positive for FCoV. Ten of 11 samples from cats with confirmed FIP without neurological signs had macrophages in the CSF, with all 10 being ICC-positive. In cats with other CNS disorders, 11/17 had macrophages, two of which stained positively. In cats with diseases other than FIP and without neurological disorders, 2/3 revealed macrophages, with one cat showing positive ICC staining. Diagnosis of FIP via CSF ICC had a sensitivity of 85.0% and a specificity of 83.3%. PPV and NPV were 85.0% and 83.3%. Conclusions and relevance CSF ICC is a highly sensitive test for ante-mortem diagnosis of FIP manifesting in the CNS. However, CNS ICC specificity is too low to confirm FIP and the method should only be applied in conjunction with other features such as CSF cytology. CNS ICC could be helpful to discover pre-neurological stages of CNS FIP.
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Affiliation(s)
- Stefanie Gruendl
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet, Munich, Germany
| | - Kaspar Matiasek
- Section of Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet, Munich, Germany
| | - Lara Matiasek
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet, Munich, Germany
| | - Andrea Fischer
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet, Munich, Germany
| | - Sandra Felten
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet, Munich, Germany
| | | | - Katrin Hartmann
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet, Munich, Germany
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Felten S, Matiasek K, Gruendl S, Sangl L, Hartmann K. Utility of an immunocytochemical assay using aqueous humor in the diagnosis of feline infectious peritonitis. Vet Ophthalmol 2017; 21:27-34. [PMID: 28493448 PMCID: PMC7169266 DOI: 10.1111/vop.12474] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Objective In cats suffering from feline infectious peritonitis (FIP) without effusion, antemortem diagnosis is challenging. Uveitis is common in these cats. It was the aim of this study to evaluate sensitivity and specificity of an immunocytochemical assay (ICC) in aqueous humor of cats suspected of having FIP. Animals studied The study included 26 cats with immunohistochemically confirmed FIP and 12 control cats for which FIP was suspected due to similar clinical or laboratory changes, but which suffered from other diseases confirmed via histopathology. Procedures All aqueous humor samples were collected postmortem by paracentesis. ICC was carried out as avidin–biotin complex method. Sensitivity, specificity, and the overall accuracy including 95% confidence intervals (95% CI) were calculated. Results Immunocytochemistry was positive in 16 of 25 cats with FIP and 2 of 11 control cats (one cat with lymphoma, one with pulmonary adenocarcinoma). Aqueous humor samples of one cat with FIP and of one control cat were excluded from statistical analysis. Sensitivity was 64.0% (95% CI: 42.5–82.0); specificity 81.8% (95% CI: 48.2–97.7); and overall accuracy 69.4% (95% CI: 51.9–83.7). Conclusions As false‐positive results occurred and specificity is most important in the diagnosis of FIP, the diagnostic utility of ICC in aqueous humor is limited. Further studies are required to clarify the origin of false‐positive ICC results.
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Affiliation(s)
- Sandra Felten
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstrasse 13, Munich, 80539, Germany
| | - Kaspar Matiasek
- Section of Clinical & Comparative Neuropathology, Institute of Veterinary Pathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstrasse 13, Munich, 80539, Germany
| | - Stefanie Gruendl
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstrasse 13, Munich, 80539, Germany
| | - Laura Sangl
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstrasse 13, Munich, 80539, Germany
| | - Katrin Hartmann
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universitaet Muenchen, Veterinaerstrasse 13, Munich, 80539, Germany
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Longstaff L, Porter E, Crossley VJ, Hayhow SE, Helps CR, Tasker S. Feline coronavirus quantitative reverse transcriptase polymerase chain reaction on effusion samples in cats with and without feline infectious peritonitis. J Feline Med Surg 2017; 19:240-245. [PMID: 26474594 PMCID: PMC10816577 DOI: 10.1177/1098612x15606957] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Objectives The aim of the study was to determine whether feline coronavirus (FCoV) RNA in effusion samples can be used as a diagnostic marker of feline infectious peritonitis (FIP); and in FCoV RNA-positive samples to examine amino acid codons in the FCoV spike protein at positions 1058 and 1060 where leucine and alanine, respectively, have been associated with systemic or virulent (FIP) FCoV infection. Methods Total RNA was extracted from effusion samples from 20 cats with confirmed FIP and 23 cats with other diseases. Feline coronavirus RNA was detected using a reverse transcriptase quantitative polymerase chain reaction assay (qRT-PCR), and positive samples underwent pyrosequencing of position 1058 with or without Sanger sequencing of position 1060 in the FCoV spike protein. Results Seventeen (85%) of the effusion samples from 20 cats with FIP were positive for FCoV RNA, whereas none of the 23 cats with other diseases were positive. Pyrosequencing of the 17 FCoV-positive samples showed that 11 (65%) of the cats had leucine and two (12%) had methionine at position 1058. Of the latter two samples with methionine, one had alanine at position 1060. Conclusions and relevance A positive FCoV qRT-PCR result on effusions appears specific for FIP and may be a useful diagnostic marker for FIP in cats with effusions. The majority of FCoVs contained amino acid changes previously associated with systemic spread or virulence (FIP) of the virus.
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Affiliation(s)
- Louise Longstaff
- The Feline Centre, Langford Veterinary Services and School of Veterinary Sciences, University of Bristol, Langford, Bristol, UK
| | - Emily Porter
- School of Veterinary Sciences, University of Bristol, Langford, Bristol, UK
| | - Victoria J Crossley
- The Feline Centre, Langford Veterinary Services and School of Veterinary Sciences, University of Bristol, Langford, Bristol, UK
- Current address: Clinical Sciences and Services, Royal Veterinary College, Royal College Street, London, UK
| | - Sophie E Hayhow
- School of Veterinary Sciences, University of Bristol, Langford, Bristol, UK
| | - Christopher R Helps
- Molecular Diagnostic Unit, Langford Veterinary Services, Langford, Bristol, UK
| | - Séverine Tasker
- The Feline Centre, Langford Veterinary Services and School of Veterinary Sciences, University of Bristol, Langford, Bristol, UK
- Molecular Diagnostic Unit, Langford Veterinary Services, Langford, Bristol, UK
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Reverse transcriptase loop-mediated isothermal amplification for the detection of feline coronavirus. J Virol Methods 2017; 243:105-108. [PMID: 28109842 PMCID: PMC7113849 DOI: 10.1016/j.jviromet.2017.01.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 01/12/2017] [Accepted: 01/14/2017] [Indexed: 11/20/2022]
Abstract
The Feline coronavirus (FCoV) is the etiological agent of feline infectious peritonitis (FIP), a lethal disease of felids. The role of molecular methods is controversial for the diagnosis of FIP, while essential for the identification of the shedders. Thus, a fast and inexpensive method for the detection of FCoV could be beneficial, especially in multicat environments. A reverse transcription loop mediated isothermal amplification (RT-LAMP) assay was developed. RNA extraction and RT-nPCR for FCoV were performed on thirty-two samples (11 faeces, 9 blood, 8 effusions, and 4 lymph nodes) collected from 27 cats. Six RT-LAMP primers were designed from the same conserved region of RT-nPCR, and the assay was run at 63°C for one hour. Results were evaluated through both agarose gel run and hydroxynapthol blue (HNB) dye and then compared with RT-nPCR results for the assessment of sensitivity and specificity. The overall specificity was 100%, but the sensitivity was 50% and 54.5% for agarose gel and HNB respectively. Therefore, RT-LAMP seems optimal to confirm the presence of the virus, but not applicable to exclude it.
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