Methanobrevibacter smithii Archaemia in Febrile Patients With Bacteremia, Including Those With Endocarditis.

BACKGROUND: The spectrum of infections caused by methanogens remains to be described. We searched for methanogens in the blood of febrile patients using specific tools. METHODS: Blood culture samples routinely collected in patients with fever were prospectively screened by specific PCR assays for methanogens. Positive samples were observed by autofluorescence and electron microscopy, analyzed by metagenomics and cultured using previously developed methods. Blood culture bottles experimentally inoculated were used as controls. The presence of methanogens in vascular and cardiac tissues was assessed by indirect immunofluorescence, fluorescent in situ hybridization and PCR-based investigations. RESULTS: PCR detection attempted in 7,716 blood samples, was negative in all 1,312 aerobic bottles and 810 bacterial culture-negative anaerobic bottles. PCRs were positive in 27/5,594 (0.5%) bacterial culture-positive anaerobic bottles collected from 26 patients. Sequencing confirmed Methanobrevibacter smithii associated with staphylococci in 14 patients, Enterobacteriaceae in nine patients and streptococci in three patients. Metagenomics confirmed M. smithii in five samples, and M. smithii was isolated in broth from two samples; the genomes of these two isolates were sequenced. Blood cultures experimentally inoculated with Enterobacteriaceae, Staphylococcus epidermidis or Staphylococcus hominis yielded hydrogen, but no methane, authentifying observational data. Three patients diagnosed with infectious mitral endocarditis, were indisputably diagnosed by microscopy, PCR-based detections and culture: we showed M. smithii microscopically and by a specific PCR followed by sequencing method in two of three cardiovascular tissues. CONCLUSIONS: Using appropriate laboratory methods, M. smithii is demonstrated as causing archaemia and endocarditis in febrile patients who are coinfected by bacteria.

Acquisition of multidrug-resistant bacteria and encoding genes among French pilgrims during the 2017 and 2018 Hajj.

The objective of this study is to determine the acquisition of multidrug-resistant (MDR) bacteria and antibiotic resistance-encoding genes by French Hajj pilgrims and associated risk factors. Pilgrims traveling during the 2017 and 2018 Hajj were recruited. All pilgrims underwent two successive systematic nasopharyngeal and rectal swabs, pre- and post-Hajj. Specific culture media were used to screen for MDR bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant bacteria, and extended spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E). qPCR was used to identify antibiotic resistance-encoding genes from cultured isolates. Direct screening of genes encoding for colistin resistance (mcr-1, 2, 3, 4, 5, and 8) from nasopharyngeal and rectal swabs was performed using qPCR, and positive qPCR results were simultaneously tested by sequencing. There were 268 pilgrims included. The percentage of pilgrims acquiring MDR bacteria during the Hajj was 19.4%. A total of 81 strains were isolated (1 carbapenem-resistant Acinetobacter baumannii, 12 MRSA, and 68 ESBL-E). ESBL-E strains were found in rectal samples of 6.0% pilgrims pre-Hajj and of 16.4% pilgrims post-Hajj. Only 0.4% pilgrims were positive for CARB post-Hajj and 1.9% carried nasal MRSA pre- and post-Hajj. In addition, 23 (8.6%) post-Hajj rectal swabs were positive for mcr genes (19 mcr-1 gene and 4 mcr-4 gene). No significant association was found between co-factors and acquisition of MDR bacteria or mcr genes. MDR bacteria and genes are acquired by pilgrims during the Hajj mass gathering. Rationalization of antibiotic consumption and implementation of measures to prevent transmission of bacteria among pilgrims during the event are of paramount importance.

Marseille scoring system for empiric treatment of infective endocarditis.

Despite advances in medical, surgical, and critical care, infective endocarditis (IE) remains associated with considerable morbidity and mortality. We evaluated the performance of the Marseille score, including clinical data and biological tests obtained within 2 h, to identify patients at high risk of IE in order to initiate early antimicrobial treatment. This was secondarily confirmed using modified ESC criteria combined with molecular testing and (18)fluorodeoxyglucose-positron emission tomography/computed tomography as diagnostic tools. In a prospective cohort study, we enrolled 484 patients with cardiovascular predisposition and clinical suspicion of IE from 2011 to 2013. The final diagnosis was definite IE in 123 patients and possible IE in 107. Marseille score was calculated adding one point for each present parameter (range 0-9). This score includes clinical, epidemiological (male, fever, splenomegaly, clubbing, vascular disease and stroke) and biological criteria (Leucocytes >10,000/mm3, sedimentation rate (SR) > 50/mm or C reactive protein >10 mg/L and hemoglobin <100 g/l). A score of 2 or more performed best in predicting IE in patients with predisposing heart lesions. Sensitivity was better on left-side heart lesions (94%) than on right-side heart lesions (85%) (p = 0.04) and better for valvulopathy (94%) than intra cardiac devices (84%) (p = 0.02). The predictive positive value of prosthetic valves was greater than that of native valves (p = 0.02). Using our simple Marseille score combined with our standardized diagnostic procedures would help improve IE management by focusing on early empiric treatment within 2 h of admission for patients with cardiac predisposition factors.

Kocuria massiliensis sp. nov, a new bacterial species isolated from a patient with foot osteomyelitis.

Most of the species from the genus Kocuria are environmental or commensals of mammalian skin and oral bacteria, and had rarely been associated with human infection. However, recent reports showed an increase of the clinical role of these bacteria in human infectious diseases. Most of the cases occurred in hospitals and were device related. They included bacteremia, peritonitis, abscess, endocarditis and ocular infection. We here describe the main characteristics and the draft genome of Kocuria massiliensis sp. nov., strain P3598T (CSURP3598), a new Kocuria species that caused foot osteomyelitis in a 78-year-old woman. The improvement of diagnostic tools for the identification of bacteria in microbiological laboratories, including MALDI-TOF MS and 16S rRNA sequencing, largely contributed to the emergence and to the expansion of the clinical spectrum of infections caused by Kocuria spp. To the best of our knowledge, we report here the first case of osteomyelitis with a bacterial species from the genus Kocuria.

Evaluation of empirical treatment for blood culture-negative endocarditis.

OBJECTIVES: Much progress has been made in understanding the main causes of blood culture-negative endocarditis (BCNE). Few studies concerning BCNE treatment (due to previous antibiotics used or fastidious pathogens) are available. We performed this study to evaluate the effectiveness of our therapeutic protocol in BCNE, based on compliance with the protocol, outcome and 1 year mortality. PATIENTS AND METHODS: We collected prospectively and analysed retrospectively cases of BCNE between 2002 and 2014, using a simplified and standardized protocol developed by our multidisciplinary team. We apply two kinds of protocols to treat BCNE, which include only four intravenous antimicrobial agents: amoxicillin, vancomycin, gentamicin and amphotericin B. RESULTS: We had 177 patients with definite BCNE. There were 154 (87.0%) patients treated with both appropriate antimicrobial agents and appropriate duration of treatment. We analysed the causes of inappropriate treatment in 13 (7.3%) cases and inappropriate duration in 10 (5.6%) cases. The treatment changes were justified in all cases except one of discharge against medical advice. The fatality rate was 5.1% (nine cases) and all deaths occurred in the group of patients who were treated with appropriate treatment; however, four deaths were not attributable to empirical treatment failure. Concerning the other deaths, the lack of surgical management, in association with empirical treatment, could explain our protocol's failure, such as poorly tolerated surgery. CONCLUSIONS: Our protocol is efficient and our mortality rate was low, compared with the literature review. This may result from a strategy that uses a sampling procedure and a standardized protocol at the same time.

Fatal Neisseria macacae infective endocarditis: first report.

INTRODUCTION: Neisseria macacae is a Gram-negative diplococcus, found in the oropharynx of healthy Rhesus Monkeys. Infections caused by N. macacae in humans are extremely rare. CASE PRESENTATION: We present here the first case of N. macacae infective endocarditis in a 65-year-old man with a native aortic valve infection complicated by a peri-aortic abscess. N. macacae was isolated from blood culture and was found on the cardiac valve using 16S rDNA detection. Despite an appropriate antibiotic therapy, and aortic homograft replacement, and mitral repair, the patient died 4 days after surgery from a massive hemorrhagic stroke.

Aggregatibacter aphrophilus chronic lacrimal canaliculitis: a case report.

BACKGROUND: Chronic canaliculitis is often misdiagnosed as conjunctivitis, delaying proper documentation and management. Aggregatibacter aphrophillus has not been implicated in chronic canaliculitis. CASE PRESENTATION: We report a case of unilateral chronic epiphora associated with chronic lacrimal canaliculitis resistant to prolonged topical antibiotic treatment in a 65-year-old woman without notable medical history. Canaculotomy, curettage with removal of concretions and tubing with silicone stent for six weeks resolved this chronic infection. Culturing lacrimal secretions and concretions yielded Aggregatibacter aphrophilus in pure culture. Histological analyses showed elongated seed clusters surrounded by neutrophils. Fluorescence in Situ Hybridization confirmed the presence of bacteria in two distinctive concretions. CONCLUSION: This first documented case of A. aphrophilus chronic lacrimal canaliculitis illustrates that optimal surgical management of chronic lacrimal canaliculitis allows for both accurate microbiological diagnosis and treatment.

Impact of the SARS-CoV-2 Pandemic on the Management and Prognosis of Infective Endocarditis.

BACKGROUND: Infective endocarditis (IE) is a serious condition which is difficult to diagnose and to treat, both medically and surgically. OBJECTIVES: The objective of this study was to evaluate the impact of the SARS-CoV-2 pandemic on the management of patients with IE. METHODS: We conducted a single-centre retrospective study including patients hospitalized for IE during the pandemic (Group 2) compared with the same period the year before (Group 1). We compared clinical, laboratory, imagery, therapeutic, and patient outcomes between the two groups. RESULTS: A total of 283 patients were managed for possible or definite IE (164 in Group 1 and 119 in Group 2). There were more intravenous drug-related IE patients in Group 2 (p = 0.009). There was no significant difference in surgery including intra-cardiac device extraction (p = 0.412) or time to surgery (p = 0.894). The one-year mortality was similar in both groups (16% versus 17.7%, p = 0.704). The recurrence rate was not significantly different between the two groups (5.9% in Group 2 versus 9.1% in Group 1, p = 0.311). CONCLUSIONS: The SARS-CoV-2 pandemic did not appear to have had a negative impact on the management of patients with IE. Maintenance of the activities of the endocarditis team within the referral centre probably contributed to this result. Nevertheless, the high proportion of intravenous drug-addicted patients in the pandemic cohort suggests that the SARS-CoV-2 pandemic had a major psychosocial impact.

Atrioventricular conduction disorders in aortic valve infective endocarditis.

BACKGROUND: Aortic valve infective endocarditis may be complicated by high-degree atrioventricular block in up to 10-20% of cases. AIM: To assess high-degree atrioventricular block occurrence, contributing factors, prognosis and evolution in patients referred for aortic infective endocarditis. METHODS: Two hundred and five patients referred for aortic valve infective endocarditis between January 2018 and March 2021 were included in this study. A comprehensive assessment of clinical, electrocardiographic, biological, microbiological and imaging data was conducted, with a follow-up carried out over 1 year. RESULTS: High-degree atrioventricular block occurred in 22 (11%) patients. In univariate analysis, high-degree atrioventricular block was associated with first-degree heart block at admission (odds ratio 3.1; P=0.015), periannular complication on echocardiography (odds ratio 6.9; P<0.001) and severe biological inflammatory syndrome, notably C-reactive protein (127 vs 90mg/L; P=0.011). In-hospital mortality (12.7%) was higher in patients with high-degree atrioventricular block (odds ratio 4.0; P=0.011) in univariate analysis. Of the 16 patients implanted with a permanent pacemaker for high-degree atrioventricular block and interrogated, only four (25%) were dependent on the pacing function at 1-year follow-up. CONCLUSIONS: High-degree atrioventricular block is associated with high inflammation markers and periannular complications, especially if first-degree heart block is identified at admission. High-degree atrioventricular block is a marker of infectious severity, and tends to raise the in-hospital mortality rate. Systematic assessment of patients admitted for infective endocarditis suspicion, considering these contributing factors, could indicate intensive care unit monitoring or even temporary pacemaker implantation in those at highest risk.

Immunoglobulin G anticardiolipin antibodies and progression to Q fever endocarditis.

BACKGROUND: Immunoglobulin G (IgG) anticardiolipin (aCL) antibodies are associated with valvulopathy and endocarditis in patients with lupus and other diseases. During acute Q fever, high IgG aCL prevalence has been reported, but the clinical significance remains unknown. METHODS: To test if increased IgG aCL at acute Q fever diagnosis is associated with an increased risk of progression to endocarditis, all patients diagnosed in the French National Referral Center for Q fever from January 2007 to December 2011 were included and followed regularly until January 2013 in a 5-year prospective cohort study. Q fever endocarditis was defined according to recently updated criteria. RESULTS: Seventy-two patients were followed for a median time of 31 months (interquartile range, 18-47 months). Of these, 13 patients with valvulopathy without antibiotic prophylaxis progressed to endocarditis. IgG aCL levels were highly prevalent (57%) and significantly higher in the presence of a valvulopathy (P = .005). Using Cox regression analysis, highly increased levels of IgG aCL (adjusted hazard ratio [AHR], 12.95; 95% confidence interval, 2.85-58.95; P = .001) and high levels of phase II immunoglobulin M (IgM; AHR, 6.59; 95% CI, 1.37-31.62; P = .018) were the only independent predictors of progression to endocarditis. CONCLUSIONS: Rapid progression from acute Q fever to endocarditis is associated with high levels of IgG aCL and high levels of phase II IgM, findings that should be critical in the prevention of endocarditis.

Deciphering genomic virulence traits of a Staphylococcus epidermidis strain causing native-valve endocarditis.

We applied real-time genome sequencing to a Staphylococcus epidermidis strain that caused native-aortic-valve endocarditis in a 26-year-old patient. The 2.5-Mb genome from strain CSUR P278 exhibited a unique sequence type among S. epidermidis strains and contained 32 genes previously considered virulence genes in this species.

Identification of rare pathogenic bacteria in a clinical microbiology laboratory: impact of matrix-assisted laser desorption ionization-time of flight mass spectrometry.

During the past 5 years, matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) has become a powerful tool for routine identification in many clinical laboratories. We analyzed our 11-year experience in routine identification of clinical isolates (40 months using MALDI-TOF MS and 91 months using conventional phenotypic identification [CPI]). Among the 286,842 clonal isolates, 284,899 isolates of 459 species were identified. The remaining 1,951 isolates were misidentified and required confirmation using a second phenotypic identification for 670 isolates and using a molecular technique for 1,273 isolates of 339 species. MALDI-TOF MS annually identified 112 species, i.e., 36 species/10,000 isolates, compared to 44 species, i.e., 19 species/10,000 isolates, for CPI. Only 50 isolates required second phenotypic identifications during the MALDI-TOF MS period (i.e., 4.5 reidentifications/10,000 isolates) compared with 620 isolates during the CPI period (i.e., 35.2/10,000 isolates). We identified 128 bacterial species rarely reported as human pathogens, including 48 using phenotypic techniques (22 using CPI and 37 using MALDI-TOF MS). Another 75 rare species were identified using molecular methods. MALDI-TOF MS reduced the time required for identification by 55-fold and 169-fold and the cost by 5-fold and 96-fold compared with CPI and gene sequencing, respectively. MALDI-TOF MS was a powerful tool not only for routine bacterial identification but also for identification of rare bacterial species implicated in human infectious diseases. The ability to rapidly identify bacterial species rarely described as pathogens in specific clinical specimens will help us to study the clinical burden resulting from the emergence of these species as human pathogens, and MALDI-TOF MS may be considered an alternative to molecular methods in clinical laboratories.

Infectious endocarditis detected by PET/CT in a patient with a prosthetic knee infection: case report and review of the literature.

We report a case illustrating the potential use of 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography (PET/CT) for the diagnosis of infective endocarditis (IE) in an 84-y-old woman who had a history of chronic left knee osteitis and a mitral cardiac valve bioprosthesis replacement and a pacemaker. She developed a polymicrobial knee infection 15 days after her total knee replacement. Transoesophageal echocardiography showed a new mitral regurgitation, but no vegetation or abscess. PET/CT showed hypermetabolic hyperactivity around the mitral cardiac valve prosthesis and the intracardiac pacemaker leads. We found 17 case reports and 2 case series of IE in which PET/CT showed encouraging results for the detection of IE. PET/CT may be used in patients with a suspicion of IE who do not have echocardiographic evidence of IE. It may also be useful for identifying the portal of entry of an infection and for identifying secondary foci (mycotic aneurysm).

Multimodality imaging in marantic endocarditis associated with cancer: a multicentric cohort study.

AIMS: We aimed to assess the role of multimodality imaging (MMI) in the diagnosis of marantic endocarditis (ME) associated with cancers and to describe the clinical characteristics, management, and outcome of these patients. METHODS AND RESULTS: In a retrospective multicentric study including four tertiary centres for the treatment of endocarditis in France and Belgium, patients with a diagnosis of ME were included. Demographic, MMI [echocardiography, computed tomography (CT), and 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT)], and management data were collected. Long-term mortality was analysed. Between November 2011 and August 2021, 47 patients with a diagnosis of ME were included. Mean age was 65 ± 11 years. ME occurred in 43 cases (91%) on native valves. Vegetations were detected by echocardiography in all cases and in 12 cases (26%) by CT. No patient had an increased cardiac 18F-FDG valve uptake. The most common cardiac valve involved was aortic (34 cases, 73%). Twenty-two patients (46%) had a known cancer before ME, and 25 cases (54%) were diagnosed thanks to multimodality imaging. 18FDG PET/CT was performed in 30 patients (64%) and allowed a new diagnosis of cancer in 14 patients (30%). Systemic embolism was frequent (40 patients, 85% of cases). Forty-one patients (87%) were treated medically with anticoagulation therapy. One-year mortality was 55% (26 patients). CONCLUSION: ME remains associated with a high risk of complications and death.

Preliminary landscape of Candidatus Saccharibacteria in the human microbiome.

Introduction: Candidate Phyla Radiation (CPR) and more specifically Candidatus Saccharibacteria (TM7) have now been established as ubiquitous members of the human oral microbiota. Additionally, CPR have been reported in the gastrointestinal and urogenital tracts. However, the exploration of new human niches has been limited to date. Methods: In this study, we performed a prospective and retrospective screening of TM7 in human samples using standard PCR, real-time PCR, scanning electron microscopy (SEM) and shotgun metagenomics. Results: Using Real-time PCR and standard PCR, oral samples presented the highest TM7 prevalence followed by fecal samples, breast milk samples, vaginal samples and urine samples. Surprisingly, TM7 were also detected in infectious samples, namely cardiac valves and blood cultures at a low prevalence (under 3%). Moreover, we observed CPR-like structures using SEM in all sample types except cardiac valves. The reconstruction of TM7 genomes in oral and fecal samples from shotgun metagenomics reads further confirmed their high prevalence in some samples. Conclusion: This study confirmed, through their detection in multiple human samples, that TM7 are human commensals that can also be found in clinical settings. Their detection in clinical samples warrants further studies to explore their role in a pathological setting.

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.

Legionella longbeachae and endocarditis.

We report a case of infectious endocarditis attributable to Legionella longbeachae. L. longbeachae is usually associated with lung infections. It is commonly found in composted waste wood products. L. longbeachae should be regarded as an agent of infectious endocarditis, notably in the context of gardening involving handling of potting soils.

The timing of surgery influences mortality and morbidity in adults with severe complicated infective endocarditis: a propensity analysis.

AIMS: To determine whether the timing of surgery could influence mortality and morbidity in adults with complicated infective endocarditis (IE). METHODS AND RESULTS: In 291 consecutive adults with definite IE who underwent surgery during the active phase, we compared those operated on within the first week of antimicrobial therapy (n=95) to those operated on later (n=191). The impact of the timing of surgery on 6-month mortality, relapses, and postoperative valvular dysfunctions (PVD) was analysed using propensity score (PS) analyses. After stratification of the cohort into quintiles based on the PS, ≤1st week surgery was associated with a trend of decrease in 6-month mortality in the quintile of patients with the most likelihood of undergoing this early surgical management [quintile 5: 11% vs. 33%, odds ratio (OR)=0.18, 95% CI (confidence interval) 0.04-0.83, P=0.03]. Patients of this subgroup were younger, were more likely to have Staphylococcus aureus infections, congestive heart failure, and larger vegetations. Besides, ≤1st week surgery was associated with an increased number of relapses or PVD (16% vs. 4%, adjusted OR=2.9, 95% CI 0.99-8.40, P=0.05). CONCLUSION: Surgery performed very early may improve survival in patients with the most severe complicated IE. However, a greater risk of relapses and PVD should be expected when surgery is performed very early.

Description of Acinetobacter ihumii sp. nov., Microbacterium ihumii sp. nov., and Gulosibacter massiliensis sp. nov., three new bacteria isolated from human blood.

Blood is precious tissue that is normally sterile. With the aim of diagnosing the cause of bacteremia, three bacterial strains were isolated from three different individuals. Strains Marseille-P7157T and Marseille-Q2854T are Gram-stain positive, non-spore-forming rod-shaped bacteria, while strain Marseille-P8049T is a Gram-stain negative, motile, non-spore-forming and rod-shaped bacterium. The major fatty acids found (>30%) were hexadecanoic acid for strain Marseille-P8049T and 12-methyl tetradecanoic acid for both strains Marseille-P7157T and Marseille-P2854T. The 16S rRNA gene sequence analysis shows that strains Marseille-P8049 and Marseille-Q2854T have sequence similarity of 96.8%, 99.04%, and 98.3% with Acinetobacter ursingii strain LUH3792 (NR_025392.1), Gulosibacter faecalis strain B187 (NR_041812.1), and Schaalia canis strain CCUG 41706 (NR_025366.1), respectively. In addition, strains Marseille-Q2854T, Marseille-P8049T and Marseille-P7157T shared with their closely related species cited above the following DDH values: 19.5%, 24.4%, and 20.2%, respectively. Based on these phenotypic and genomic findings, we consider that strains Marseille-P8049T (= CSUR P8049 = CECT 30350), Marseille-P2854T ( = CSUR Q2854 = CECT 30120) and Marseille-P7157T ( = CSUR P7157 = CECT 30048) are new bacterial species, for which the names Acinetobacter ihumii sp. nov., Microbacterium ihumii sp. nov., and Gulosibacter massiliensis sp. nov., are proposed.

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.