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We report necropsy findings in a captive 60-year-old female greater flamingo (Phoenicopterus roseus) that died suddenly following rupture of a pulmonary artery aneurysm. Histologically, there was focally extensive, intramural granulomatous inflammation with intralesional fungal hyphae, and adjacent severe mixed-cell inflammation and acute haemorrhage at the rupture site. Aspergillus fumigatus was identified as the aetiological agent following DNA PCR amplification and sequencing from paraffin-embedded pulmonary artery tissue sections. The most likely explanation is that this lesion was a consequence of haematogenous spread, secondary to mycotic pneumonia or aerosacculitis, following aspiration of A. fumigatus conidiospores. However, no further fungal-related lesions were observed on gross or histopathological examination., Competing Interests: Conflict of Interest Statement The authors declare no potential conflicts of interest in relation to the research, authorship or publication of this article., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Listeria monocytogenes-associated endovascular infections are not well characterized., Methods: Retrospective study of 71 culture-proven cases reported to the French National Reference Center for Listeria from 1993 to 2018., Results: Seventy-one cases were identified: 42 with vascular aneurysms/prosthetic infections, 27 with endocarditis, 2 with both. Fifty-eight were men (82%); median age was 75 years [46-92]; 93% reported co-morbidities (66/71), including 50% with immunosuppressive conditions. Vascular infections consisted of infected aneurysms (68%) or prosthetic graft infections (32%); vascular rupture was reported in 25/42 (60%). Tissue samples grew L. monocytogenes in 98% (43/44) and blood cultures in 64% (27/42). Endocarditis cases involved prosthetic or native valves or intracardiac devices in respectively 62% (18/29), 28% (8/29) and 10% (3/29). Infected valves were aortic (62%, 16/26), mitral (31%, 8/26) or both (8%, 2/26); 38% patients required surgery; 45% displayed heart failure; 17% had concomitant neurolisteriosis. In-hospital mortality in vascular infections was 12% (5/42) and 41% (12/29) for Lm-associated endocarditis., Conclusions: Endovascular listeriosis is a rare but severe infection. It manifests as vascular infections and endocarditis, mostly in older patients with vascular or cardiac valve prosthetic devices and co-morbidities. Mortality in Lm-associated endocarditis is twice higher than with other pathogens, requiring prompt recognition and treatment., (Copyright © 2019. Published by Elsevier Ltd.)

Endocarditis is a consideration in the differential diagnosis when masses are seen on echocardiography in a patient with congenital heart disease. We present a case of insidious development of endocarditis caused by Streptobacillus moniliformis in a seven-month-old baby after a rat bite, when the baby was three months of age.

A 39-year-old Philipino man presented with acute onset fever and headache. Neurological examination was normal except for neck stiffness. There was no history of chest pain, cough or breathlessness. Cerebrospinal fluid (CSF) showed a mild increase in protein with normal sugar and lymphocytic pleocytosis. CSF PCR for herpes simplex and varicella zoster virus was negative. He developed acute right haemiplegia a week after hospitalisation. MRI showed acute infarct in the left centrum semiovale. His angiogram showed aneurysm in the left subclavian artery and aortic arch. The mycoplasma antibody test came positive with very high titres, while rest of the workup was negative. He was treated with azithromycin and his symptoms improved completely.He was asymptomatic on follow-up after a month. His repeat immunoglobulin G mycoplasma antibody titre showed elevation. Mycoplasma infection is a treatable cause of meningoencephalitis and stroke secondary to vasculitis. Arterial aneurysms are known to occur with mycoplasma infection although rare., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Salmonella enterica subsp. enterica serovar Abortusequi is a pathogen restricted to horses. Our investigation targeted 4 draft horses (9-10 months old) kept on a Japanese farm that had suffered an outbreak of S. Abortusequi abortion. The 4 horses were suspected to be carriers of the bacterium owing to their high agglutination titers (≥1:2,560) in tube agglutination testing. The owners' on-farm observations confirmed that the horses had no apparent abnormalities, and S. Abortusequi was not isolated from their blood, rectal swabs, or sternal bone marrow fluid at antemortem investigation. However, at autopsy, all horses displayed the following: suppurative aneurysm of the cranial mesenteric artery with heavy infection with Strongylus vulgaris larvae; heavy intestinal parasitic infection with Gasterophilus intestinalis, Parascaris equorum, Anoplocephala perfoliata, and S. vulgaris; and enlargement of the systemic lymph nodes. In each case, large numbers of S. Abortusequi were isolated from the anterior mesenteric artery thrombus. The thrombus isolates harbored a single virulence plasmid, and the pulsed-field gel electrophoresis profiles of the isolates were identical not only to each other but also to those of Japanese enzootic strains of S. Abortusequi. These results reveal that parasitic aneurysms of the cranial mesenteric artery should be considered an important possible site of carriage of S. Abortusequi in horses. The results also suggest high clonality of the isolated serovar in the horse population in Japan., (© 2016 The Author(s).)

Background: Candidatus Neoehrlichia mikurensis is a newly discovered noncultivatable bacterium spread among ticks and rodents in Europe and Asia that can infect humans, particularly immunocompromised patients., Methods: We compiled clinical and laboratory data from 11 patients with hematological malignances or autoimmune diseases who were diagnosed with Candidatus N. mikurensis infection in Europe 2010-2013. Both published (6) and unpublished cases (5) were included., Results: The patients had a median age of 67, were mostly male (8/11), and resided in Sweden, Switzerland, Germany, and the Czech Republic. All but one had ongoing or recent immune suppressive treatment and a majority were splenectomized (8/11). Less than half of them recalled tick exposure. The most frequent symptoms were fever (11/11), localized pain afflicting muscles and/or joints (8/11), vascular and thromboembolic events (6/11), that is, deep vein thrombosis (4), transitory ischemic attacks (2), pulmonary embolism (1), and arterial aneurysm (1). Typical laboratory findings were elevated C-reactive protein, leukocytosis with neutrophilia, and anemia. Median time from onset of symptoms to correct diagnosis was 2 months. In at least 4 cases, the condition was interpreted to be due to the underlying disease, and immunosuppressive therapy was scheduled. All patients recovered completely when doxycycline was administered., Conclusions: Candidatus N. mikurensis is an emerging tick-borne pathogen that may give rise to a systemic inflammatory syndrome in persons with hematologic or autoimmune diseases that could be mistaken for recurrence of the underlying disease and/or unrelated arteriosclerotic vascular events. Awareness of this new pathogen is warranted among rheumatologists, hematologists, oncologists, and infectious disease specialists., (© The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Takayasu's arteritis (TA) is an inflammatory vasculitis of aorta and its branches, its low incidence limited our recognition to this entity. We sometimes can confuse this disease with polyarteritis nodosa and other vasculitis when no conventional "big artery" involved in TA cases. Here we report a 26-year-old man with Takayasu's arteritis who presented with a provisional intracranial granulomatosis first and then saccular aneurysms between celiac trunk and arteria hepatica communis and many other proteus manifestations, which is seldom described before.

Mycobacterium malmoense is recognised as an environmental pathogen predominantly affecting populations in Northern Europe. In immuno-competent individuals, isolated pulmonary disease remains the commonest presentation. The authors report a rare case describing a mycotic popliteal aneurysm caused by M malmoense in a 74-year-old man from Hastings, UK with co-existing pulmonary M malmoense disease. Primary pulmonary disease was confirmed by a combination of history, examination and positive radiological and microbiological findings. Tissue analysis of the aneurysm wall during popliteal aneurysm repair confirmed the presence of disseminated M malmoense. Histological analysis of the aneurysm wall showed non-caseating granulomata. The patient completed a 2 year course of rifampicin, ethambutol and clarithromycin which eradicated the organism from his sputum. Further progress has been complicated by the development of an aspergilloma at the site of his eradicated pulmonary M malmoense disease and the need for angioplasty to his bypass grafts 1 year postsurgery.

A 46-year-old man with a medical history notable only for schizophrenia was admitted to hospital with complaints of general fatigue and high fever. Transthoracic echocardiography on day 6 after admission demonstrated a large vegetation (17 mm) on the anterior leaflet of the mitral valve with mild regurgitation and mild aortic regurgitation. The patient also complained of abdominal pain. Abdominal computed tomography showed a remarkable enlargement of the superior mesenteric artery aneurysm (SMAA). An excision of the SMAA and double valve replacement was performed, and the patient was administered a six-week course of intravenous antibiotic therapy.

The most common clinical presentation of chronic Q fever is endocarditis with infections of aneurysms or vascular prostheses being the second most common presentation. Here, the authors report a case of vascular chronic Q fever. In this patient, a renal artery aneurysm was discovered by abdominal and pelvic CT during a systematic investigation to identify predisposing factors to chronic Q fever because of high antibody titres in a patient with valve disease.

Aim: Microbial biofilm matrix contains polysaccharides and proteins and can require extracellular nucleic acids for initial formation. Experiments were designed to identify infectious pathogens in human aneurysms and to characterize biofilm formed by calcified human arterial-derived nanoparticles., Materials & Method: A total of 26 different microbial pathogens were isolated from 48 inflammatory aneurysms. Consistent amounts (0.49 McFarland units) of nanoparticles derived from similar tissue were seeded into 24-well plates and cultured for 21 days in the absence (control) or presence of RNase, tetracycline or gentamicin., Results: Control biofilm developed within 14 days, as detected by concanavalin A and BacLight Green staining. The formation of biofilm in wells treated with RNase was not different from the control; however, gentamicin partially inhibited and tetracycline completely inhibited biofilm formation. Therefore, nanoparticle biofilm retains some characteristics of conventional bacterial biofilm and requires protein-calcium interactions, although extracellular RNA is not required., Conclusion: This model system may also allow study of nanosized vesicles derived from donor tissue, including any microbes present, and could provide a useful tool for in vitro investigation of nanoparticle biofilm formation.

Pythium insidiosum is a fungus that causes disease in both animals and humans. Human pythiosis is an emerging disease in the tropical, subtropical, and temperate regions of the world, occurring in localized and systemic or vascular forms. Most patients with arterial pythiosis have an underlying hemoglobinopathy, such as thalassemia. A case is presented of a thalassemic horse stable worker who developed an ulcerative cutaneous lesion on the lower left leg followed by progressive ascending involvement of the arteries of that extremity with a necrotizing arteritis with aneurysm formation. P. insidiosum was not isolated from the ulcer by culture or wet potassium hydroxide preparations but was diagnosed by histopathologic study of a biopsy. P. insidiosum infection was quickly confirmed by immunoblot method, aiding in preoperative decision making. Many systemic antibiotics or antimycotics have not been effective in the treatment of systemic pythiosis, and radical surgical removal of all infected tissue is the only method to ensure patient survival. An orally administered saturated solution of potassium iodide, amphotericin B-oral solution, and terbinafine has succeeded only in the cutaneous form but had no favorable effect on vascular pythiosis. It is likely that immunotherapy, successfully used in animal pythiosis, may be beneficial in the treatment of human vascular pythiosis.

We report a case of mitral valve aneurysm in a 30-year-old man presenting with fatigue, malaise, and fever 10 weeks after emergent aortic valve replacement for endocarditis. The transthoracic echocardiogram demonstrated perivalvular aortic regurgitation, but no abscess cavity was defined. Cardiac magnetic resonance imaging (MRI) revealed a mitral valve leaflet aneurysm. Both aortic and mitral valves were replaced with mechanical prostheses. Pathology of the excised mitral valve showed a focally hemorrhagic aneurysm of the anterior leaflet with myxoid degeneration and focal calcification. Early diagnosis and intervention are important to treat this rare, potentially fatal complication of aortic valve endocarditis. Cardiac MRI provided an accurate and useful preoperative diagnostic evaluation.

Introduction: Infection is a frequent cause of morbidity and mortality in solid organ transplant recipients. It may occur at different periods after transplantation. We report four cases of mycotic aneurysms due to Candida albicans (CA) in renal transplant recipients occurring early after kidney transplantation., Case Reports: Four patients (three men, one woman) aged from 24 to 55 years who underwent cadaveric renal transplantation from three different donors developed a mycotic aneurysm at 9 to 90 days after transplantation. In all cases aneurysms were located at the anastomosis between the renal graft artery and the iliac axis. The clinical presentations were fever in three cases, including endocarditis in one patient or deterioration of graft function in two cases and hemorrhagic shock secondary to a ruptured renal artery in the fourth case, which led to death. The arterial aneurysm was discovered at autopsy. The diagnosis of a mycotic aneurysm was based on morphological investigations: echotomography, spiral computed tomography, and arteriography. In all cases bacteriological studies (blood culture, culture of the aneurysmal wall and content) isolated CA. In three patients CA was isolated from the preservation solution; it was of the same phenotype as the one isolated from the aneurysm in one recipient. Antifungal therapy was started in patients who lived, but all kidney transplants had to be removed. Anatomical results of arterial reconstructions were satisfactory in all cases and remained so during the follow-up., Conclusion: The insidious presentation and clinical course of mycotic aneurysms due to CA require a high degree of suspicion to make the correct diagnosis.

A 68-year-old diabetic woman suffered from mycotic aneurysm due to Klebsiella pneumoniae over her abdominal aorta; she received surgical intervention, followed by treatment with first-generation cephalosporins for 6 months. She was hospitalized again 11 months later because of another episode of mycotic aneurysm caused by K. pneumoniae on her thoracic aorta. Fingerprinting generated by pulsed-field gel electrophoresis and infrequent-restriction-site polymerase indicated K. pneumoniae isolates of the identical clonal strain were responsible for these two mycotic-aneurysm episodes. Unfortunately, nosocomial pneumonia developed at the second hospitalization; blood and purposefully sampled feces specimen cultures both grew CTX-M-24-producing K. pneumoniae, which were of the same strain and genetically nonrelated to the K. pneumoniae strain causing mycotic aneurysms earlier. This is the first report on infection due to CTX-M-24-producing K. pneumoniae. It is unclear whether the prolonged use of first-generation cephalosporins in this case selected a strain of enteric organism possessing the ESBL in question, which was capable of passing this ESBL plasmid to the K. pneumoniae strain causing the nosocomial infection. This report suggests that further observation is needed before one can draw a conclusion on the possibility of the selection of ESBL enteric organism by extensive exposure to first-generation cephalosporins.

Kawasaki syndrome (KS) has been reported to be associated with selective expansion of Vbeta2+ T cells and either staphylococcal toxic shock syndrome toxin-1 or streptococcal pyrogenic exotoxin C in uncomplicated cases. However, there have been no previous studies on the role of superantigens in KS associated with coronary artery disease, the major complication of this illness. The present study characterized bacteria isolated from three acute KS patients who developed coronary artery disease. Staphylococcus aureus secreting either TSST-1 (n = 3) or exfoliative toxin A (n = 1), both known to stimulate expansion of Vbeta2+ T cells, were isolated from all three patients. The percent Vbeta2+ T cells was determined in three patients with coronary artery disease. On presentation, one patient demonstrated reduction, whereas the other two showed expansion, of Vbeta2+ T cells. Repeat analyses of the latter two children showed their percent Vbeta2+ T cells to decrease toward normal. These observations suggest that coronary artery disease in KS may result from superantigenic stimulation of Vbeta2+ T cells. This is also the first demonstration of an association of staphylococcal exfoliative toxin with acute KS. The observation that three different bacterial toxins associated with KS are potent activators of Vbeta2+ T cells suggests an important role for this T cell subset in the pathogenesis of this autoimmune disease.

Occult infection was investigated as an etiologic factor in the formation of femoral anastomotic pseudoaneurysms associated with prosthetic vascular grafts. Forty-five femoral pseudoaneurysms with no clinical evidence of infection 10 to 173 months after prosthetic graft placement were consecutively studied. The explanted Dacron or explanted polytetrafluoroethylene graft material was cultured in trypticase soy broth and ultrasonically oscillated to remove adherent bacteria. All patients were treated by excision of the pseudoaneurysm and surrounding perigraft capsule and in situ replacement with an interposition prosthetic graft. Thirty-two bacterial isolates were recovered from 27 (60%) of the specimens, with coagulase negative staphylococci (Staphylococcus epidermidis S. warneri, S. hominis, S. capitis) accounting for 24 of the recovered species. No infection of the replacement graft developed in any patient and no recurrent pseudoaneurysms were observed. Bacterial colonization may occur at implantation or during subsequent procedures when the prosthetic graft is exposed. This chronic infection can be diagnosed by means of sensitive culture techniques that dislodge adherent bacteria from the graft surface. On grounds of the observations reported in this study, there appears to be suggestive evidence that an occult infectious process may be one of the factors that play a role in the development of some femoral anastomotic pseudoaneurysms.

Infected thrombus in an abdominal aortic aneurysm represents a potential source of subsequent aortic graft sepsis. Previous reports have documented a 10 to 15 percent incidence of positive results of culture of the contents of an abdominal aortic aneurysm and have recommended prolonged postoperative organism-specific antibiotic therapy when a positive culture is encountered. In our study, we cultured the intraluminal thrombus during elective aneurysm repair in 64 patients with abdominal aortic aneurysms and found bacterial growth in 9 (14 percent of all patients). Eight of the nine patients received no antibiotic therapy other than the routine prophylaxis regimen, and no evidence of either early or late prosthetic graft sepsis occurred (mean follow-up 25 months). We conclude that a positive result of culture may not imply clinical infection at the time of operation and that prolonged postoperative organism-specific antibiotic therapy does not appear necessary in the patient with an asymptomatic aneurysm and no overt evidence of infection of the aneurysm at the time of operation.

After reviewing the physiopathology, the authors report the principal features of infectious arterial disease observed in a department of infectious diseases. Excluding iatrogenic arteritis, particularly after vascular surgery, and some vasculitis in which an infectious agent may play a role, only the classical but now rare causes are described: rickettsial disease, syphilis and typhoid. The most commonly observed problem at present is infectious aneurysms: primary aneurysms secondary to atherosclerosis in which salmonella is by far the predominant organism, before the staphylococci and streptococci. The most serious complication is the major risk of rupture which may be the presenting event. Secondary aneurysms are essentially those of endocarditis. The mechanism is not fully understood and they occur at different stages of the course of the disease. The main problem associated with these aneurysms is their multiplicity and localisation; the intracranial forms are the most common and most serious in the experience of the authors, with their difficulties of diagnosis and treatment: extracranial aneurysms are usually located in the main limb arteries. Adjacent secondary aneurysms are exceptionally rare. Tuberculous and viral causes of aneurysm are among the rarest etiologies discussed.