Polymyalgia rheumatica and giant cell arteritis following COVID-19 vaccination: Results from a nationwide survey.

We conducted a national in-depth analysis including pharmacovigilance reports and clinical study to assess the reporting rate (RR) and to determine the clinical profile of polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) in COVID-19-vaccinated individuals. First, based on the French pharmacovigilance database, we estimated the RR of PMR and GCA cases in individuals aged over 50 who developed their initial symptoms within one month of receiving the BNT162b2 mRNA, mRNA-1273, ChAdOx1 nCoV-19, and Ad26.COV2.S vaccines. We then conducted a nationwide survey to gather clinical profiles, therapeutic management, and follow-up data from individuals registered in the pharmacovigilance study. A total of 70 854 684 COVID-19 vaccine doses were administered to 25 260 485 adults, among which, 179 cases of PMR (RR 7. 1 cases/1 000 000 persons) and 54 cases of GCA (RR 2. 1 cases/1 000 000 persons) have been reported. The nationwide survey allowed the characterization of 60 PMR and 35 GCA cases. Median time to the onset of first symptoms was 10 (range 2-30) and 7 (range 2-25) days for PMR and GCA, respectively. Phenotype, GCA-related ischemic complications and -large vessel vasculitis as well as therapeutic management and follow-up seemed similar according to the number of vaccine shots received and when compared to the literature data of unvaccinated population. Although rare, the short time between immunization and the onset of first symptoms of PMR and GCA suggests a temporal association. Physician should be aware of this potential vaccine-related phenomenon.

Mycobacterium tuberculosis Resides in Macrophages in Laryngeal Tuberculosis: A Case Report.

Laryngeal tuberculosis is a rare form of extrapulmonary tuberculosis that questions the natural history of this infection. We report one such case in which a pathological examination of a laryngeal biopsy revealed granulomatous inflammation with caseous necrosis. Further investigations combining immunofluorescence detection of macrophages and in situ hybridization of Mycobacterium tuberculosis indicated the presence of Mycobacterium tuberculosis (M. tuberculosis) in laryngeal granulomatous inflammatory lesions. This observation suggests that the natural history of laryngeal tuberculosis does not differ from that of other forms, guiding early diagnosis in patients with laryngeal lesions to ensure appropriate check-ups and treatment.

The Role of Platelets in Infective Endocarditis.

Over the last decade, the incidence of infective endocarditis (IE) has increased, with a change in the frequency of causative bacteria. Early evidence has substantially demonstrated the crucial role of bacterial interaction with human platelets, with no clear mechanistic characterization in the pathogenesis of IE. The pathogenesis of endocarditis is so complex and atypical that it is still unclear how and why certain bacterial species will induce the formation of vegetation. In this review, we will analyze the key role of platelets in the physiopathology of endocarditis and in the formation of vegetation, depending on the bacterial species. We provide a comprehensive outline of the involvement of platelets in the host immune response, investigate the latest developments in platelet therapy, and discuss prospective research avenues for solving the mechanistic enigma of bacteria-platelet interaction for preventive and curative medicine.

Infection and Persistence of Coxiella burnetii Clinical Isolate in the Placental Environment.

Infection by Coxiella burnetii, the etiological agent of Q fever, poses the risk of causing severe obstetrical complications in pregnant women. C. burnetii is known for its placental tropism based on animal models of infection. The Nine Mile strain has been mostly used to study C. burnetii pathogenicity but the contribution of human isolates to C. burnetii pathogenicity is poorly understood. In this study, we compared five C. burnetii isolates from human placentas with C. burnetii strains including Nine Mile (NM) as reference. Comparative genomic analysis revealed that the Cb122 isolate was distinct from other placental isolates and the C. burnetii NM strain with a set of unique genes involved in energy generation and a type 1 secretion system. The infection of Balb/C mice with the Cb122 isolate showed higher virulence than that of NM or other placental isolates. We evaluated the pathogenicity of the Cb122 isolate by in vitro and ex vivo experiments. As C. burnetii is known to infect and survive within macrophages, we isolated monocytes and placental macrophages from healthy donors and infected them with the Cb122 isolate and the reference strain. We showed that bacteria from the Cb122 isolate were less internalized by monocyte-derived macrophages (MDM) than NM bacteria but the reference strain and the Cb122 isolate were similarly internalized by placental macrophages. The Cb122 isolate and the reference strain survived similarly in the two macrophage types. While the Cb122 isolate and the NM strain stimulated a poorly inflammatory program in MDM, they elicited an inflammatory program in placenta macrophages. We also reported that the Cb122 isolate and NM strain were internalized by trophoblastic cell lines and primary trophoblasts without specific replicative profiles. Placental explants were then infected with the Cb122 isolate and the NM strain. The bacteria from the Cb122 isolate were enriched in the chorionic villous foetal side. It is likely that the Cb122 isolate exhibited increased virulence in the multicellular environment provided by explants. Taken together, these results showed that the placental isolate of C. burnetii exhibits a specific infectious profile but its pathogenic role is not as high as the host immune response in pregnant women.

Clinical and Echocardiographic Features of Patients With Infective Endocarditis and Bicuspid Aortic Valve According to Echocardiographic Definition of Valve Morphology.

BACKGROUND: The influence of different bicuspid aortic valve (BAV) morphology in the clinical course of infective endocarditis (IE) has not yet been investigated. This study aimed to describe the clinical and echocardiographic features of IE in patients with BAV (BAVIE) according to valve morphology. METHODS: Patients with definite BAVIE prospectively enrolled in 4 high-volume referral centers from 2000 to 2019 were evaluated and divided into 2 groups according to the echocardiographic definition of fused BAV morphology: right-left coronary (RL type) and right noncoronary or left noncoronary (non-RL type) cusp fusion. All patients were followed up for 1 year. RESULTS: One hundred thirty-eight patients with BAVIE were included (77.7% male; median age, 52 [36.83-61.00] years): 112 patients with RL type (81%) and 26 patients with non-RL type BAV (19%), with no significant differences in age, sex, and comorbidities between groups. Although 43% of the cohort had known BAV, the referral was late after symptom onset, particularly for the RL phenotype; time from symptom onset to hospitalization >30 days (31.3% vs 11.5%; P = .032) and New York Heart Association class ≥ II (64.3% vs 42.3%; P = .039) were more frequent in patients with RL type BAV than in patients with non-RL type BAV. Conversely, patients with non-RL type BAV had a higher incidence of hemorrhagic stroke (19.2% vs 5.4%; P = .034) and high-grade atrioventricular block (11.5% vs 0.9%; P = .021). Streptococcus viridans was more frequently isolated in patients with non-RL type BAV than in patients with RL type BAV (44% vs 24.1%; P = .045). No difference in short- and intermediate-term mortality was observed between groups. CONCLUSIONS: Clinical profile and echocardiographic features in BAVIE patients may differ according to valve morphology, and patients with BAVIE appear to be referred late, even when BAV disease is previously known.

Influence of the healthcare pathway on the outcome of patients with infective endocarditis.

AIMS: To determine the prognosis of patients treated for infective endocarditis (IE) according to their healthcare pathway. To assess how the ESC guidelines are implemented concerning the performance of transoesophageal echocardiography, the use of antibiotic therapy, and the performance of valve surgery; and to compare the epidemiological profile of IE according to the type of centres in which the patients are hospitalized. METHODS AND RESULTS: In a prospective multicentric study including 22 hospitals in the South-East of France, 342 patients were classified into three groups according to their healthcare pathway: 119 patients diagnosed and taken care entirely in a reference centre or hospital with cardiac surgery [Referral Center (RC) group], 111 patients diagnosed and initially taken care in a non-RC (NRC), then referred in a centre including cardiac surgery [transferred to the Referral Center (TRC) group] and 112 patients totally taken care in the NRC (NRC group). One-year mortality was 26% (88 deaths) and was not significantly different between Groups 1 and 2 (20 vs. 21%, P = 0.83). Patients in the NRC group had a higher mortality (37%) compared with patients in the RC and TRC groups (P < 0.001). ESC guidelines were not implemented similarly depending on the healthcare pathway (P = 0.04). Patients in the NRC group were significantly older (P < 0.001) and had more comorbidities (P < 0.001) than patients treated in referral centres. CONCLUSION: Prognosis of patients with IE is influenced by their healthcare pathway. Patients treated exclusively in NRC have a worse prognosis than patients treated in referral or surgical centres.

Booklice Liposcelis bostrychophila Naturally Infected by Rickettsia felis Cause Fever and Experimental Pneumonia in Mammals.

BACKGROUND: Rickettsia felis is emergent in tropical areas. Despite its high morbidity, its natural history has not yet been fully determined. We investigated the role of the common household booklouse, Liposcelis bostrychophila, recently found to harbor R. felis. METHODS: Blood samples from 372 febrile patients from Senegalese villages, as well as nasal and skin samples from 264 asymptomatic individuals, were tested for cat flea-associated and booklice-associated strains of R. felis. Dust samples from beds were collected to isolate booklice and R. felis. Mice were infected with aerosol of R. felis strain from naturally infected booklice. RESULTS: Forty febrile patients (11%) were infected by R. felis, including 26 (7%) by the booklice-associated strain. Nine nasal samples (3.4%) and 28 skin samples (10.6%) contained R. felis, including 7 and 24, respectively, with the booklice-associated strain. The presence of live L. bostrychophila was observed in 32 dust samples (16.8%); R. felis was identified in 62 dust samples (32.5%). Several mice samples were positive for R. felis; interstitial lymphohistiocytic infiltrates were identified in lungs. CONCLUSIONS: Liposcelis bostrychophila may be a reservoir of R. felis. The booklice-associated strain is pathogenic in mammals, causing pneumonia. Human infection may be acquired via inhalation of infected booklice particles.

A Massive Number of Extracellular Tropheryma whipplei in Infective Endocarditis: A Case Report and Literature Review.

Whipple's disease (WD) is a chronic multisystemic infection caused by Tropheryma whipplei. If this bacterium presents an intracellular localization, associated with rare diseases and without pathognomonic signs, it is often subject to a misunderstanding of its physiopathology, often a misdiagnosis or simply an oversight. Here, we report the case of a patient treated for presumed rheumatoid arthritis. Recently, this patient presented to the hospital with infectious endocarditis. After surgery and histological analysis, we discovered the presence of T. whipplei. Electron microscopy allowed us to discover an atypical bacterial organization with a very large number of bacteria present in the extracellular medium in vegetation and valvular tissue. This atypical presentation we report here might be explained by the anti-inflammatory treatment administrated for our patient's initial diagnosis of rheumatoid arthritis.

Control of CDH1/E-Cadherin Gene Expression and Release of a Soluble Form of E-Cadherin in SARS-CoV-2 Infected Caco-2 Intestinal Cells: Physiopathological Consequences for the Intestinal Forms of COVID-19.

COVID-19 is the biggest pandemic the world has seen this century. Alongside the respiratory damage observed in patients with severe forms of the disease, gastrointestinal symptoms have been frequently reported. These symptoms (e.g., diarrhoea), sometimes precede the development of respiratory tract illnesses, as if the digestive tract was a major target during early SARS-CoV-2 dissemination. We hypothesize that in patients carrying intestinal SARS-CoV-2, the virus may trigger epithelial barrier damage through the disruption of E-cadherin (E-cad) adherens junctions, thereby contributing to the overall gastrointestinal symptoms of COVID-19. Here, we use an intestinal Caco-2 cell line of human origin which expresses the viral receptor/co-receptor as well as the membrane anchored cell surface adhesion protein E-cad to investigate the expression of E-cad after exposure to SARS-CoV-2. We found that the expression of CDH1/E-cad mRNA was significantly lower in cells infected with SARS-CoV-2 at 24 hours post-infection, compared to virus-free Caco-2 cells. The viral receptor ACE2 mRNA expression was specifically down-regulated in SARS-CoV-2-infected Caco-2 cells, while it remained stable in HCoV-OC43-infected Caco-2 cells, a virus which uses HLA class I instead of ACE2 to enter cells. It is worth noting that SARS-CoV-2 induces lower transcription of TMPRSS2 (involved in viral entry) and higher expression of B0AT1 mRNA (that encodes a protein known to co-express with ACE2 on intestinal cells). At 48 hours post-exposure to the virus, we also detected a small but significant increase of soluble E-cad protein (sE-cad) in the culture supernatant of SARS-CoV-2-infected Caco-2 cells. The increase of sE-cad release was also found in the intestinal HT29 cell line when infected by SARS-CoV-2. Beside the dysregulation of E-cad, SARS-CoV-2 infection of Caco-2 cells also leads to the dysregulation of other cell adhesion proteins (occludin, JAMA-A, zonulin, connexin-43 and PECAM-1). Taken together, these results shed light on the fact that infection of Caco-2 cells with SARS-CoV-2 affects tight-, adherens-, and gap-junctions. Moreover, intestinal tissues damage was associated to the intranasal SARS-CoV-2 infection in human ACE2 transgenic mice.

Whipple's disease and Tropheryma whipplei infections: from bench to bedside.

Whipple's disease is a chronic and systemic disease caused by the Gram-positive bacterium Tropheryma whipplei that primarily affects the gastrointestinal tract. Data from the last two decades have substantially increased our knowledge of the spectrum and our understanding of T whipplei infections. Although T whipplei seems ubiquitously present in the environment, Whipple's disease itself is very rare. Remarkably, primary infections can be symptomatic, but most cases result in bacterial clearance and seroconversion. However, some individuals are unable to clear the bacterium leading to persistence and asymptomatic carriage. In very rare cases, which might be associated with a subtle immune defect, T whipplei replication is uncontrolled and manifests as classical Whipple's disease or T whipplei localised infections. In this review, we provide a comprehensive outline of T whipplei infection, including the epidemiology, clinical manifestations, diagnosis, and treatment. We also provide an up-to-date overview of our understanding of the host immune response and pathophysiology and discuss future research avenues to resolve the lacking pieces of the puzzle of T whipplei infections.

Multisystem inflammatory syndrome-related refractory cardiogenic shock in adults after coronavirus disease 2019 infection: a case series.

Background: A novel multisystem inflammatory syndrome in children (MIS-C) temporally associated with the coronavirus disease 2019 (COVID-19) infection has been reported, arising weeks after the peak incidence of COVID-19 infection in adults. Patients with MIS-C have been reported to have cardiac involvement and clinical features overlapping with other acute inflammatory syndromes such as Kawasaki disease, toxic shock syndrome, and macrophage activation syndrome. Multisystem inflammatory syndrome in children may follow COVID-19 infection, most of the time after its asymptomatic form, even though it can lead to serious and life-threatening illness. Case summary: In this case series, we discuss two cases of young adults with no former medical history who fit with the criteria defined in MIS-C. They both developed a refractory cardiogenic shock and required intensive care treatment including mechanical circulatory support, specifically the use of venous-arterial extracorporeal membrane oxygenation. They were both treated early with intravenous immune globulin and adjunctive high-dose steroids. They recovered ad integrum in less than 2 weeks. Discussion: Multisystem inflammatory syndrome in children occurs 2-4 weeks after infection with severe acute respiratory syndrome coronavirus 2. Patients with MIS-C should ideally be managed in an intensive care environment since rapid clinical deterioration may occur. It would be preferable to have a multidisciplinary care to improve outcomes. Patients should be monitored for shock. Elucidating the mechanism of this new entity may have importance for understanding COVID-19 far beyond the patients who have had MIS-C to date. The pathogenesis seems to involve post-infectious immune dysregulation so early administration intravenous immune globulin associated with corticosteroids appears appropriate. It implies early recognition of the syndrome even in young adults.

Mitral valve repair is better than mitral valve replacement in native mitral valve endocarditis: Results from a prospective matched cohort.

BACKGROUND: In native mitral valve infective endocarditis (NMIE), the respective values of mitral valve repair (MVRep) and replacement (MVR) are still debated. AIM: To compare MVRep and MVR in a large prospective matched cohort. METHODS: Between 2010 and 2017, all consecutive patients operated on for NMIE in our centre were included prospectively. Clinical and outcome features were compared between the two groups. Primary endpoint was event-free survival, including death, reoperation and relapse. Univariate and multivariable survival analyses and a propensity score analysis were performed. RESULTS: Among 152 patients, 115 (75.7%) underwent MVRep, and 37 (24.3%) MVR. Median follow-up was 28±22months. Surgery was performed during the active phase in 75.0% of patients (25.7% on an urgent basis). Compared with the MVRep group, patients in the MVR group were more frequently intravenous drug abusers (10.8% vs. 0.9%; P=0.016), had a more frequent history of rheumatic fever (13.5% vs. 0%; P=0.001), more aortic abscesses (16.7% vs. 3.5%; P=0.018), larger vegetations (16.6±8.1mm vs. 12.6±9.9mm; P=0.042) and poorer New York Heart Association status (P=0.006). Overall mortality was lower in the MVRep group than in MVR group (11.3% vs. 29.3%; P=0.018). Event-free survival was better in the MVRep group than in the MVR group in univariate analysis (hazard ratio: 2.72, 95% confidence interval: 1.34-5.52; P=0.004). Survival analysis in the propensity-matched cohort showed that MVRep was safer than MVR (log rank test: P=0.018). Multivariable analysis using the Cox proportional hazard model confirmed this finding (hazard ratio: 3.48, 95% confidence interval: 1.15-10.61; P=0.03). CONCLUSIONS: MVRep is feasible in most cases of NMIE and, when technically possible, should be preferred, even in urgent surgery.

GNS561 Exhibits Potent Antiviral Activity against SARS-CoV-2 through Autophagy Inhibition.

Since December 2019, SARS-CoV-2 has spread quickly worldwide, leading to more than 280 million confirmed cases, including over 5,000,000 deaths. Interestingly, coronaviruses were found to subvert and hijack autophagic process to allow their viral replication. Autophagy-modulating compounds thus rapidly emerged as an attractive strategy to fight SARS-CoV-2 infection, including the well-known chloroquine (CQ). Here, we investigated the antiviral activity and associated mechanism of GNS561/Ezurpimtrostat, a small lysosomotropic molecule inhibitor of late-stage autophagy. Interestingly, GNS561 exhibited antiviral activity of 6-40 nM depending on the viral strain considered, currently positioning it as the most powerful molecule investigated in SARS-CoV-2 infection. We then showed that GNS561 was located in lysosome-associated-membrane-protein-2-positive (LAMP2-positive) lysosomes, together with SARS-CoV-2. Moreover, GNS561 increased LC3-II spot size and caused the accumulation of autophagic vacuoles and the presence of multilamellar bodies, suggesting that GNS561 disrupted the autophagy mechanism. To confirm our findings, we used the K18-hACE2 mouse model and highlighted that GNS561 treatment led to a decline in SARS-CoV-2 virions in the lungs associated with a disruption of the autophagy pathway. Overall, our study highlights GNS561 as a powerful drug in the treatment of SARS-CoV-2 infection and supports the hypothesis that autophagy blockers could be an alternative strategy for COVID-19.

Immunohistochemical diagnosis of human infectious diseases: a review.

BACKGROUND: Immunohistochemistry (IHC) using monoclonal and polyclonal antibodies is a useful diagnostic method for detecting pathogen antigens in fixed tissues, complementing the direct diagnosis of infectious diseases by PCR and culture on fresh tissues. It was first implemented in a seminal publication by Albert Coons in 1941. MAIN BODY: Of 14,198 publications retrieved from the PubMed, Google, Google Scholar and Science Direct databases up to December 2021, 230 were selected for a review of IHC techniques, protocols and results. The methodological evolutions of IHC and its application to the diagnosis of infectious diseases, more specifically lice-borne diseases, sexually transmitted diseases and skin infections, were critically examined. A total of 59 different pathogens have been detected once in 22 different tissues and organs; and yet non-cultured, fastidious and intracellular pathogens accounted for the vast majority of pathogens detected by IHC. Auto-IHC, incorporating patient serum as the primary antibody, applied to diseased heart valves surgically collected from blood culture-negative endocarditis patients, detected unidentified Gram-positive cocci and microorganisms which were subsequently identified as Coxiella burnetii, Bartonella quintana, Bartonella henselae and Tropheryma whipplei. The application of IHC to ancient tissues dated between the ends of the Ptolemaic period to over 70 years ago, have also contributed to paleomicrobiology diagnoses. CONCLUSION: IHC plays an important role in diagnostic of infectious diseases in tissue samples. Paleo-auto-IHC derived from auto-IHC, is under development for detecting non-identified pathogens from ancient specimens.

Congenital Infection of Severe Acute Respiratory Syndrome Coronavirus 2 With Intrauterine Fetal Death: A Clinicopathological Study With Molecular Analysis.

BACKGROUND: Observations of vertical transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection from mother to fetus have recently been described in the literature. However, the consequences of such transmission, whether fetal or neonatal, are poorly understood. METHODS: From a case of in utero fetal death at 24+2 weeks of gestation that occurred 7 days after the diagnosis of symptomatic SARS-CoV-2 infection in the mother, we isolated the incriminating virus by immunochemistry and molecular techniques in several fetal tissues, with a variant analysis of the SARS-CoV-2 genome. RESULTS: The fetal demise could be explained by the presence of placental histological lesions, such as histiocytic intervillositis and trophoblastic necrosis, in addition to fetal tissue damage. We observed mild fetal growth retardation and visceral damage to the liver, causing hepatocellular damage and hemosiderosis. To the best of our knowledge, this is the first report in the literature of fetal demise secondary to maternal-fetal transmission of SARSCoV- 2 with a congenital infection and a pathological description of placental and fetal tissue damage. CONCLUSIONS: SARS-CoV-2 was identified in both specimens using 3 independent techniques (immunochemistry, real-time quantitative polymerase chain reaction, and realtime digital polymerase chain reaction). Furthermore, the incriminating variant has been identified.

Presence of SARS-CoV-2 in a Cornea Transplant.

BACKGROUND: The SARS-CoV-2 pandemic has impacted tissue transplantation procedures since conjunctivas were found to be associated with coronavirus infection. Here, we investigated infection of a cornea graft from a COVID-19-positive donor. METHODS: In order to evaluate the presence of SARS-CoV-2 in the cornea graft we first carried out a qRT-PCR and then we investigated the presence of SARS-CoV-2 by fluorescence and electron microscopy. CONCLUSIONS: Although the cornea graft was found to be negative by qRT-PCR, we were able to show the presence of SARS-CoV-2 in corneal cells expressing the SARS-CoV-2 receptor, ACE2. Taken together, our findings may have important implications for the use of corneal tissue in graft indications and open the debate on SARS-CoV-2 transmissibility.

Infective endocarditis with neurological complications: Delaying cardiac surgery is associated with worse outcome.

BACKGROUND: Infective endocarditis (IE) is associated with a high mortality rate, related in part to neurological complications. Studies suggest that valvular surgery should be performed early when indicated, but is often delayed by the presence of neurological complications. AIM: To assess the effect of delaying surgery in patients with IE and neurological complications and to identify factors predictive of death. METHODS: In a prospective, single-centre study in a referral centre for IE, all patients with IE underwent systematic screening for neurological complications. The primary outcome was 6-month death. In patients presenting with neurological complications, the prognosis according to surgical status was analysed and a Cox regression model used to identify variables predictive of death. RESULTS: Between April 2014 and January 2018, 351 patients with a definite diagnosis of left-sided IE were included. Ninety-four patients (26.8%) presented with at least one neurological complication. Fifty-nine patients (17.7%) died during 6-month follow-up. Six-month mortality rates did not differ significantly between patients with and without neurological complications (P=0.60). Forty patients had a temporary surgical contraindication because of neurological complications. During the period of surgical contraindication, seven of these patients (17.5%) died, six (15.0%) presented a new embolic event, and 12 (30.0%) presented cardiac or septic deterioration. In multivariable analysis, predictive factors of death in patients presenting with neurological complications were temporary surgical contraindication (hazard ratio 7.36, 95% confidence interval 1.61-33.67; P=0.010) and presence of a mechanical prosthetic valve (hazard ratio 16.40, 95% confidence interval 2.22-121.17; P=0.006). CONCLUSIONS: Patients with a temporary surgical contraindication due to neurological complications had a higher risk of death and frequent major complications while waiting for surgery. When indicated, the decision to postpone surgery in the early phase should be weighed against the risk of infectious or cardiac deterioration.

Severe pneumonia in a street rat (Rattus norvegicus) caused by Rodentibacter rarus strain RMC2.

Background: Rodents are one of the most dangerous reservoirs and carriers of infectious diseases. Gradually, rats have become predominant in cities, sometimes staying in close vicinity to humans, pets, and other animals. Consequently, they tend to increase the transmission risk of pathogens. Case Description: Here, we report an original case of bacterial pneumonia in a street rat (Rattus norvegicus). The rat was found dead on a street in the chief town of Marseille (France) after being run over by a car. The necropsy of the corpse revealed generalized granulomatous pneumonia in almost all the pulmonary lobes. Lung lesions and predominantly multiple fibro-inflammatory areas are presumably the witness of an infectious etiology. Bacterial isolation was carried out from lung tissues. Colonies were identified by MALDI-TOF MS and confirmed by 16S rRNA sequencing. The following bacteria were identified: Staphylococcus cohnii, Bordetella bronchiseptica, Bordetella parapertussi, Corynebacterium glucuronolyticum, Pelistega suis and Rodentibacter rarus. Based on the histopathological diagnosis and the avoidance approach, the most likely etiological agent of pneumonia is therefore R. rarus, a little-known Pasteurellales bacterium that is closely related to Rodentibacter pneumotropicus. Conclusion: These data emphasize the severity of R. rarus infection in rodents. Thus, pointing out a potential risk for other animals (dogs, cats, and birds), as well as humans. The health monitoring program for rodents and rabbits pasteurellosis should now include R. rarus. Therefore, the pathological effect of the Rodentibacterspecies and/or strains needs to be better explored.