Double ANCA-positive vasculitis in a patient with infective endocarditis

A Rare Case of Anca Positivity and Antiphospholipid Antibodies in a Patient with Takayasu Arteritis: Case Report and Review of the Literature

Takayasu arteritis (TA) is a chronic large-vessel vasculitis characterized by immune-mediated panarteritis, which predominantly affects the aorta and its main branches and is most prevalent in young women. TA is unusually associated with the presence of antiphospholipid antibodies. We present a case report of a 48-year-old Caucasian woman with acute aortic dissection as an initial feature of TA, where detailed clinical, imaging and laboratory studies were performed. Computed tomography angiography (CTA) of the chest and abdomen revealed aortic dissection DeBakey I. Bentall and De Bono surgery was performed. Additional immunological tests revealed positive antineutrophil cytoplasmic antibodies (ANCAs) with the simultaneous presence of pANCA and cANCA antibodies on indirect immunofluorescence, along with anti-MPO+PR3+antibodies positivity in the absence of a clinically relevant disease. Surprisingly, antiphospholipid antibodies (aPLs) were detected. Then, we performed a thorough review of the current literature. The coexistence of aPL antibodies and dual specificity for MPO and PR3 in a patient diagnosed with Takayasu arteritis is unusual and poses a diagnostic challenge. The presented case report outlines a rare case of aortic dissection as a presenting symptom of TA, along with atypical ANCA positivity and positive APL antibodies.

Antineutrophil cytoplasmic antibodies in infective endocarditis: a case report and systematic review of the literature

Infective endocarditis (IE) may be misdiagnosed as ANCA-associated vasculitis (AAV), especially when antineutrophil cytoplasmic antibodies (ANCA) are detected. Distinguishing IE from AAV is crucial to guide therapy. However, little is known about ANCA positivity in IE patients. We present a case report and systematic review of the literature on patients with ANCA-positive IE, aiming to provide a comprehensive overview of this entity and to aid clinicians in their decisions when encountering a similar case. A systematic review of papers on original cases of ANCA-positive IE without a previous diagnosis of AAV was conducted on PubMed in accordance with PRISMA-IPD guidelines. A predefined set of clinical, laboratory, and kidney biopsy findings was extracted for each patient and presented as a narrative and quantitative synthesis. A total of 74 reports describing 181 patients with ANCA-positive IE were included (a total of 182 cases including our own case). ANCA positivity was found in 18-43% of patients with IE. Patients usually presented with subacute IE (73%) and had positive cytoplasmic ANCA-staining or anti-proteinase-3 antibodies (79%). Kidney function was impaired in 72%; kidney biopsy findings were suggestive of immune complexes in 59%, while showing pauci-immune glomerulonephritis in 37%. All were treated with antibiotics; 39% of patients also received immunosuppressants. During follow-up, 69% of patients became ANCA-negative and no diagnosis of systemic vasculitis was reported. This study reviewed the largest series of patients with ANCA-positive IE thus far and shows the overlap in clinical manifestations between IE and AAV. We therefore emphasize that clinicians should be alert to the possibility of an underlying infection when treating a patient with suspected AAV, even when reassured by ANCA positivity. Key Points • This systematic review describes - to our knowledge - the largest series of patients with ANCA-positive infective endocarditis (IE) thus far (N=182), and shows a high degree of overlap in clinical manifestations between IE and ANCA-associated vasculitis (AAV). • ANCA positivity was found in 18-43% of patients with infective endocarditis. Of patients with ANCA-positive IE, the majority (79%) showed cytoplasmic ANCA-staining or anti-PR3-antibodies. We emphasize that clinicians should be alert to the possibility of an underlying infection when treating a patient with suspected AAV, even when reassured by ANCA positivity. • In patients with IE and ANCA-associated symptoms such as acute kidney injury, an important clinical challenge is the initiation of immunosuppressive therapy. All patients with data in this series received antibiotics; 39% also received immunosuppressive therapy. In many of these patients, ANCA-associated symptoms resolved or stabilized after infection was treated. ANCA titers became negative in 69% , and a diagnosis of AAV was made in none of the cases. We therefore recommend that (empiric) antibiotic treatment remains the therapeutic cornerstone for ANCA-positive IE patients, while a watchful wait-and-see approach with respect to immunosuppression is advised.

Leucocytoclastic vasculitis due to acute bacterial endocarditis resolves with antibiotics

Infective endocarditis is associated with a variety of clinical signs, but its association with multisystem vasculitis is rarely reported. A high index of suspicion is necessary to differentiate a primary autoimmune vasculitis from an infectious cause as the wrong treatment can lead to significant morbidity and mortality. We present a 71-year-old female patient with negative blood cultures, on antibiotics for recent bacteraemia, who presented with cutaneous and renal leucocytoclastic vasculitis. Workup revealed a vegetation adjacent to her right atrial pacemaker lead consistent with infective endocarditis and her vasculitis completely resolved with appropriate antibiotics.

Antineutrophil cytoplasmic antibody-positive infective endocarditis complicated by acute kidney injury: a case report and literature review

Patients with infective endocarditis (IE) may present with multisystem disturbances resembling autoimmune diseases, such as antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). The kidneys are susceptible to damage in IE and AAV, which is a source of diagnostic ambiguity. Therefore, distinguishing infection from an inflammatory process is pivotal for guiding appropriate therapy. We report a 22-year-old man with IE characterized by ANCA positivity and complicated by acute kidney injury. A renal biopsy showed crescentic nephritis with tubulointerstitial lesions. However, transthoracic echocardiography and blood culture provided evidence of IE, and AAV was ruled out. Surgical intervention and antibiotic treatments were successful. We summarized previously reported cases of ANCA-positive IE that had renal biopsy data. We found that ANCA-positive IE can involve multiple organs. The representative renal pathology was crescentic nephritis, focal segmental glomerulonephritis, mesangial cell proliferation, tubular injury, and interstitial oedema. Immunofluorescence showed predominate C3 deposits. Electron microscopy showed electron-dense deposits in the subendothelial or mesangial areas. Eight patients received immunosuppressive therapy with excellent results. Repeated testing for bacterial pathogens and multiple renal biopsies may be useful for diagnosing ANCA-positive IE. With ANCA-positive IE, immunosuppressive therapy along with antibiotic treatments may be beneficial for recovery of renal function.

Infection-associated vasculitides

Vasculitides are disorders characterized by inflammation of the vessel walls, often caused by autoimmunity, but sometimes as a result of microbial invasion. Almost all types of microbes including bacteria, viruses, protozoa and fungi have been incriminated in the pathogenesis of vasculitis. Accurate etiological diagnosis is important since immunosuppressive treatment may lead to further deterioration if infection is the cause of vasculitis. Clinical features sometimes provide clues to the etiology. Further evaluation requires a focused and cost-effective plan of laboratory investigation. The investigations aim at establishing the diagnosis of vasculitis and identify the causative organism. An accurate diagnosis of vasculitis optimally requires histological examination and imaging. For infection-associated vasculitis, the identification of the organism requires studies of stained specimens, cultures, and/or detection of antigens and antibodies. Ideally, the treatment involves administration of an appropriate antimicrobial. In non-self-limiting types of vasculitides, glucocorticoids are needed when the symptoms are progressive, with vital organs involvement, and sometimes, when there is no antimicrobial agent of proven efficacy against the incriminated agent. Additional immunosuppressive agents or interventions must be considered when the disease is severe and/or post-infective immune mechanisms are involved in the pathogenesis, e.g., severe HBV- or HCV-associated vasculitides. Available preventative vaccinations are also crucial. The incidence of HBV-associated vasculitides dramatically decreased following HBV vaccination campaigns, and other infection-associated vasculitides may as well in the future.

Antineutrophil Cytoplasmic Antibody Induction due to Infection: A Patient with Infective Endocarditis and Chronic Hepatitis C

While antineutrophil cytoplasmic antibody (ANCA) is often used as a diagnostic marker for certain vasculitides, ANCA induction in the setting of infection is much less common. In the case of infective endocarditis, patients may present with multisystem disturbances resembling an autoimmune process, cases that may be rendered even trickier to diagnose in the face of a positive ANCA. Though not always straightforward, distinguishing an infective from an inflammatory process is pivotal in order to guide appropriate therapy. We describe an encounter with a 43-year-old male with chronically untreated hepatitis C virus infection who featured ANCA positivity while hospitalized with acute bacterial endocarditis. His case serves as a reminder of two of the few infections known to uncommonly generate ANCA positivity. We also summarize previously reported cases of ANCA positivity in the context of endocarditis and hepatitis C infections.

Antineutrophil Cytoplasmic Antibodies Associated With Infective Endocarditis

To determine the prevalence of antineutrophil cytoplasmic antibodies (ANCA) in patients with infective endocarditis (IE) in internal medicine; and to compare clinical and biochemical features and outcome between patients exhibiting IE with and without ANCA.Fifty consecutive patients with IE underwent ANCA testing. The medical records of these patients were reviewed.Of the 50 patients with IE, 12 exhibited ANCA (24%). ANCA-positive patients with IE exhibited: longer duration between the onset of first symptoms and IE diagnosis (P = 0.02); and more frequently: weight loss (P = 0.017) and renal impairment (P = 0.08), lower levels of C-reactive protein (P = 0.0009) and serum albumin (P = 0.0032), involvement of both aortic and mitral valves (P = 0.009), and longer hospital stay (P = 0.016). Under multivariate analysis, significant factors for ANCA-associated IE were: longer hospital stay (P = 0.004), lower level of serum albumin (P = 0.02), and multiple valve involvement (P = 0.04). Mortality rate was 25% in ANCA patients; death was because of IE complications in all these patients.Our study identifies a high prevalence of ANCA in unselected patients with IE in internal medicine (24%). Our findings further underscore that ANCA may be associated with a subacute form of IE leading to multiple valve involvement and more frequent renal impairment. Because death was due to IE complications in all patients, our data suggest that aggressive therapy may be required to improve such patients' outcome.