Surgical management of infected endovascular aortic stent graft secondary to Coxiella burnetii infection.

The management of an endograft infection with Coxiella burnetti (Q fever) is presented. In this case report, we describe a unique case of an endovascular aneurysm repair (EVAR) that was originally placed for a 6.4-cm abdominal aortic aneurysm with an aorto-left renal vein fistula. In retrospect, the abdominal aortic aneurysm was most likely infected at the time of EVAR. The patient presented 2 years later with a virulent infection of the stent graft requiring explantation and reconstruction. This case highlights surgical management of an infected EVAR with homograft reconstruction and subsequent antibiotic management.

Atypical Presentation of Coxiella burnetii Endocarditis: Diagnostic Considerations and the Importance of Keeping a Broad Differential.

Coxiella burnetii is a gram-negative bacterium associated with serious complications such as infective endocarditis. Early diagnosis and treatment can be difficult due to its nonspecific presentation and risk factors that include contact with farm animals or their byproducts. Here, we present an atypical presentation of infective endocarditis caused by Coxiella burnetii, where the patient had no risk factors, negative Duke criteria, and negative preliminary workup.

Infective Endocarditis Due to Q Fever From a Tick Bite: A Case Report.

Infection from Coxiella burnetti causes Q fever that manifests with vague symptoms. We report a case of an individual admitted to the hospital with recurrent fevers with a history of multiple tick bites. Further workup revealed examination and laboratory findings consistent with Q fever endocarditis. Fevers resolved with doxycycline and hydroxychloroquine. Our case highlights that suspicion for Q fever should be maintained in patients presenting to the hospital with fevers of unknown origin for prompt recognition and appropriate treatment.

Q Fever-A Neglected Zoonosis.

Q fever remains a neglected zoonosis in many developing countries including Pakistan. The causing agent Coxiella (C.) burnetii is resistant to environmental factors (such as drying, heat and many disinfectants), resulting in a long-lasting infection risk for both human and animals. As the infection is usually asymptomatic, it mostly remains undiagnosed in animals until and unless adverse pregnancy outcomes occur in a herd. In humans, the infection leads to severe endocarditis and vascular infection in chronic cases. Limited data are available on molecular epidemiology and evolution of this pathogen, especially in ruminants. Genomic studies will help speculating outbreak relationships in this scenario. Likewise, pathogenesis of C. burnetii needs to be explored by molecular studies. Awareness programs and ensuring pasteurization of the dairy milk before human consumption would help preventing Q fever zoonosis.

The First Case of Coxiella Burnetti Infection Detected Through Bone Marrow Biopsy in Vietnam.

Coxiella burnetii is an obligate intracellular bacterium that causes the zoonotic infectious disease, Q fever. The common clinical presentation is fever, hepatitis, and pneumonia; laboratory examination could reveal pancytopenia, elevated liver enzymes. In bone marrow, many fibrin ring granulomas, also known as "Doughnut" granulomas can be seen and suggest the diagnosis of Q fever. However, these bone marrow granulomas can also be presented in infectious diseases by other pathogens such as EBV, CMV, and HBV; therefore, other serology or PCR-based tests are needed to confirm the diagnosis of Q fever. We report the first case of acute Q fever in Vietnam, presented as a fever of unknown origin with hepatitis in a 53-year-old male patient. A bone marrow biopsy was performed and showed various fibrin ring granulomas; therefore, Coxiella was suspected and the diagnosis was confirmed by PCR. Some infectious diseases can cause specific changes in the bone marrow, such as Doughnut granulomas in Q fever. These features can help direct the diagnosis and decide earlier treatment for the patient.

Culture-negative polymicrobial chronic Q fever prosthetic valve infective endocarditis utilizing 16S ribosomal RNA polymerase chain reaction on explanted valvular tissue.

Coxiella burnetti is the causative organism of the zoonotic infection Q fever, of which endocarditis is one of the most common manifestations of the chronic form. Polymicrobial endocarditis with Q fever is extremely rare and is yet to be described among an Australasian cohort. SUMMARY: We present the case of a 32-year-old gardener with culture-negative chronic Q fever prosthetic valve endocarditis concomitant with another bacterial pathogen, leading to aortic root abscess formation, requiring a Bentall procedure, extracorporeal membrane oxygenation, and prolonged antimicrobial therapy, with a fatal outcome. Unique to our case, Q fever was identified early, and the second pathogen was only detected on 16S ribosomal RNA (rRNA) polymerase chain reaction of explanted valvular tissue. Given the high risk for morbidity, we recommend that screening for Q fever in endemic areas among patients with infective endocarditis from other etiologies be considered. In addition, this case highlights the role for Q fever vaccination of the at-risk population with underlying valvulopathy. Furthermore, clinicians should be aware of polymicrobial infective endocarditis and suspicious in case of patients with atypical clinical features.

Open repair of a Coxiella burnetii-associated abdominal aortic endovascular stent graft infection with a cryopreserved allograft using visceral artery pump perfusion.

Coxiella burnetii, the causative organism of Q fever, has been increasingly reported to be associated with infections of abdominal aortic aneurysms and endovascular stent grafts. We have added to the current literature by presenting a case of the surgical management of chronic Q fever that had infected a prior aortic endovascular stent graft placed for a contained rupture of an infrarenal aortic aneurysm in a 68-year-old woman. We presented our case of the surgical management of the excision and explantation of the infected aorta and stent graft, with reconstruction of the aorta using a cryopreserved aortic graft and visceral artery pump perfusion.

An Unusual Case of Myopericarditis in a Young Woman.

A 48-year-old woman with no history of cardiovascular risk factors was admitted to the emergency room with complaints of angor, dyspnea, and fever in the last 24 h. She was referred for xerostomia and xerophthalmia since 2015. At examination, the patient was polypneic with bibasal crackles. Blood tests showed leukocytosis and increased high sensitivity troponin I and C-reactive protein (CRP). The echocardiogram revealed a small pericardial effusion.  She was diagnosed with myopericarditis and started acetylsalicylic acid (ASA) and colchicine. Laboratory tests indicated the presence of positive antinuclear antibodies, double-strain DNA antibodies (anti-dsDNA), anti-Sjögren's-syndrome-related antigen A (anti-SSA), and lupus anticoagulant antibodies. Positivity for phase II immunoglobulin M and G for Coxiella burnetti was detected. As it fulfills the diagnostic criteria for a possible flare of systemic lupus erythematosus (SLE) and SS (triggered by a possible infection by C. burnetti) the patient started immunosuppressive therapy. A complete resolution of symptoms with normalization of CRP and troponin I values were observed.

Seroprevalence of Coxiella burnetii in patients presenting with acute febrile illness at Marigat District Hospital, Baringo County, Kenya.

Q fever is not routinely diagnosed in Kenyan hospitals. This study reports on Q fever in patients presenting at Marigat District Hospital, Kenya, with febrile illness. ELISA was used to detect Coxiella burnetii phase antigens. Of 406 patients, 45 (11.1%) were judged to have acute disease (phase II IgM or IgG > phase I IgG), 2 (0.5%) were chronic (phase I IgG titer >800 or phase I IgG > phase II IgG), while 26 (6.4%) had previous exposure (phase I IgG titer <800). Age (6-10 years, p = 0.002) and contact with goats (p = 0.014) were significant risk factors. Compared to immunofluorescence antibody test, the sensitivity and specificity for phase I IgG were 84% and 98%, respectfully, 46% and 100% for phase II IgG and 35% and 89% for phase II IgM. It is concluded that the low sensitivity of phase II ELISA underestimated the true burden of acute Q fever in the study population.

Expression, purification and characterization of the IcmG and IcmK proteins of the type IVB secretion system from Coxiella burnetii.

Coxiella burnetii, the causative agent of Q fever, is an intracellular bacterial pathogen. Studies on Coxiella have shown that a type IVB secretion system (T4BSS) contributes to the establishment of the infection by transferring protein molecules. In this report, we focus on two core proteins of the Coxiella T4BSS, namely the IcmG/DotF protein (CBU_1626) and the IcmK/DotH protein (CBU_1628). Here we present a method for the recombinant expression of IcmG and IcmK in E. coli. IcmG was purified by Strep-Tactin affinity chromatography and size exclusion chromatography, while for the purification of IcmK an additional anion exchange chromatography step was introduced. The yields of the purified IcmG and IcmK proteins were 1.2 mg/L and 3 mg/L, respectively. The purified proteins showed predominant band on SDS-PAGE gel of 37 kDa for the IcmG and 40 kDa for the IcmK. Protein folding is confirmed by circular dichroism spectroscopy. The dynamic light scattering experiment indicated that IcmG and IcmK existed in a homogenous form. Further Blue native PAGE indicates the presences of a monomeric form for the IcmK and IcmG. Our work lays the basis for functional exploration and structural determination of IcmG and IcmK proteins of Coxiella's secretion system.

Q fever presenting as myocarditis.

We report the case of a 19-year-old healthy adolescent, living in an urban area, admitted because of acute chest pain and extensive anterior ST elevation. Coronary arteries were normal on coronary angiography; troponins were very high, echocardiography revealed a preserved global systolic function but an alteration of the longitudinal strain in the inferolateral wall. Cardiac MRI confirmed the diagnosis of acute myocarditis. As part of the etiological workup, Coxiella burnetii serology showed an acute infection. The diagnosis of Coxiella burnetii myocarditis was retained and the patient was treated with doxycycline and corticosteroid therapy. The myocardial localization of this germ is unusual but can be serious, hence the interest of a Coxiella serology in endemic countries face to any acute myocarditis.

Detection of Multiple Intracellular Bacterial Pathogens in Haemaphysalis flava Ticks Collected from Hedgehogs in Central China.

Tickborne intracellular bacterial pathogens including Anaplasma, Coxiella burnetti, Ehrlichia, and Rickettsia cause emerging infectious diseases worldwide. PCR was used to amplify the genes of these pathogens in Haemaphysalis flava ticks collected from hedgehogs in Central China. Among 125 samples including 20 egg batches, 24 engorged females, and 81 molted male and female adult ticks, the DNA sequences and phylogenetic analysis showed that the minimum infection rate of the ticks was 4% (5/125) for A. bovis, 3.2% (4/125) for C. burnetti, 9.6%, (12/125) for E. ewingii, and 5.6% for Rickettsia including R.japonica (3.2%, 4/125) and R. raoultii (2.4%, 3/125), respectively. The prevalence of these pathogens was significantly higher in dead engorged females (83.3%, 20/24) than in eggs (5%, 1/20) and molted ticks (8.6%, 7/81). Our study indicated that H. flava ticks could be infected with multiple species of tickborne pathogens including Anaplasma, C. burnetti, Ehrlichia, and Rickettsia in Central China, and the prevalence of these pathogens was reduced during transovarial and transstadial transmission in ticks, suggesting that ticks may not be real reservoirs but only vectors for these tickborne pathogens.

Valvular fibroelastomas complicated by Coxiella burnetti endocarditis.

Cardiac papillary fibroelastoma (CPF) is a valvular tumor that may be mistaken for infective endocarditis (IE). We describe a case of CPF complicated by Coxiella burnetti IE. According to Duke's criteria, a diagnosis of IE was repeatedly considered as excluded or established during the clinical course, highlighting the criteria limitations.

Molecular detection of important abortion-causing microorganisms in preputial swab of breeding bucks using PCR-based assays.

Infectious diseases and aetiological agents related to female reproductive systems were extensively covered compared to its male counterpart. There needs a proper study to bridge this gap, where microflora and infectious agents of both male and female reproductive are mutually intelligible. With this study, we aimed to evaluate the microbial contamination of the preputial cavity and also screened for abortion-causing agents which are zoonotic as well. In goats, such types of abortions are caused by Brucella melitensis, Chlamydophila, Campylobacter and Coxiella etc. One of the major sources of contamination of semen is the preputial cavity, which is exposed to the external environment leading to spread of infection into the female via semen straws or by natural service. In the current study, good quality bucks (n = 32, Barbari = 12, Jamunapari = 10, Jakhrana = 10) which were routinely used for semen collection were screened for their preputial swabs, for the presence of the above pathogens. For detection of Brucella melitensis, OMP31 based TaqMan® probe real-time PCR assay was used, and for Chlamydia, 16srRNA gene based SYBR® green real-time PCR assay was employed for detection of Chlamydophila abortus. While for Campylobacter spp. and Coxiella burnetii, 16srRNA gene based conventional PCR and Trans-PCR were used, respectively. In the current study, of the screened preputial swabs, none of them showed positive for Brucella and Coxiella, but of the screened 32 samples 17 showed positive for Chlamydia (53.13%) and two (6.25%) showed positive for Campylobacter spp. The current study emphasizes on the farms and laboratories which were regularly involved in screening of brucellosis also often overlook the other potential non-brucella pathogens, causing abortions eventually incurring severe economic losses to the goat keepers.

Coxiella seroprevalence and risk factors in large ruminants in Bihar and Assam, India.

Coxiellosis is a zoonotic disease caused by the ubiquitous bacteria Coxiella burnetii, which can be spread either through ticks or through body fluids. In humans the infection is characterized by a febrile disease; ruminants may abort and reduce their milk yield, causing serious production losses for the farmer. In India, the disease has been known to be present since the 1970s, but little is known about the epidemiology in most states. In this cross-sectional survey in the two states of Assam and Bihar, 520 households were interviewed for risk factors, and serum samples from 744 dairy animals were analyzed using ELISA as well as PCR. Out of the farms, 17.4% had at least one seropositive animal, with significantly higher seroprevalence in Bihar (27.1%) than Assam (5.8%); and significantly more sero-positive farms in urban areas (23.1%) than rural (12.2%). On an individual animal level, 14.1% were seropositive, with higher prevalence among buffaloes than cows (28.0% versus 13.6%). Out of the seropositive animals, 10.6% had aborted during the last three years, and 37.5% had experienced problems with repeat breeding: both higher than in non-seropositive animals. In conclusion, this study indicates that coxiellosis is potentially an important cause of reproductive failures and production losses in dairy animals. The high prevalence, especially in urban areas, is a public health risk. Further research is needed to elucidate the epidemiology and identify mitigation options that could work in the different settings of different Indian states.

First Case of Q Fever Endocarditis Involving the Melody® Transcatheter Pulmonary Valve in an Afebrile Child.

In this article we report the first case of Q fever endocarditis in a 13 years old child with a percutaneous pulmonary Melody® valve. The patient had a new onset of Melody valve dysfunction associated with the combination of hepatosplenomegaly and pancytopenia but was afebrile. Although blood cultures were negative, we have further investigated in the direction of infective endocarditis by performing PCR detection and the serology of C. burnetii which were positive. A combination antibiotic therapy with doxycycline and hydroxychloroquine was started with good clinical evolution. Our case emphasizes the fact that any Melody valvular dysfuntion should be considered as a potential infective endocarditis despite the absence of typical bacterial features.

Coxiella burnetii Multilevel Disk Space Infection, Epidural Abscess, and Vertebral Osteomyelitis Secondary to Contiguous Spread From Infected Abdominal Aortic Aneurysm or Graft: Report of 4 Cases Acquired in the US and Review of the Literature.

BACKGROUND: Chronic Coxiella burnetii infections such as vertebral osteomyelitis caused by contiguous spread from an infected abdominal aortic graft or aneurysm have been rarely reported and are associated with significant morbidity and mortality. METHODS: We present the first four reported US acquired cases of Coxiella burnetii vertebral osteomyelitis caused by contiguous spread from an infected abdominal aortic graft or aneurysm. RESULTS: Presenting symptoms included progressive back pain, malaise, and weight loss with recent or remote animal exposure. Typical imaging findings demonstrated a peri-aortic collection with extension to the paraspinal muscles and vertebrae. Antibiotic regimens included doxycycline with either hydroxychloroquine or a quinolone for at least 2 years or as chronic suppression. CONCLUSIONS: C. burnetii vertebral osteomyelitis is rare and can occur by contiguous spread from an abdominal aneurysm or vascular graft infection. It should be suspected in patients where pre-antibiotic cultures are negative with animal/farming exposure.

Polymicrobial Q Fever and enterococcal aortic prosthetic valve endocarditis with aortic root abscess.

Polymicrobial endocarditis is uncommon. We present a case of polymicrobial endocarditis caused by Enterococcus faecalis and Coxiella burnetii and review previous cases of polymicrobial endocarditis involving Coxiella burnetii. Testing for Q fever should be considered in any patient with endocarditis living in an endemic area.

Update on blood culture-negative endocarditis.

Blood culture-negative endocarditis is often severe, and difficult to diagnose. The rate of non-documented infective endocarditis has decreased with the advent of molecular biology - improved performance for the diagnosis of bacterial endocarditis with blood cultures sterilized by previous antibacterial treatment - and cardiac surgery - access to the main infected focus, the endocardium, for half of the patients. Blood culture-negative endocarditis are classified in 3 main categories: (i) bacterial endocarditis with blood cultures sterilized by previous antibacterial treatment (usually due to usual endocarditis-causing bacteria, i.e. streptococci, more rarely staphylococci, or enterococci); (ii) endocarditis related to fastidious microorganisms (e.g. HACEK bacteria; defective streptococci - Gemella, Granulicatella, and Abiotrophia sp. - Propionibacterium acnes, Candida sp.): in these cases, prolonged incubation will allow identifying the causative pathogen in a few days; (iii) and the "true" blood culture-negative endocarditis, due to intra-cellular bacteria that cannot be routinely cultured in blood with currently available techniques: in France, these are most frequently Bartonella sp., Coxiella burnetti (both easily diagnosed by ad hoc serological tests), and Tropheryma whipplei (usually diagnosed by PCR on excised cardiac valve tissue). Non-infective endocarditis is rare, mostly limited to marantic endocarditis, and the rare endocarditis related to systemic diseases (lupus, Behçet).