Actinobacillus actinomycetemcomitans: a cause of pulmonary-valve endocarditis of 18 months' duration with unusual manifestations

Cryoglobulinemic vasculitis triggered by Staphylococcus aureus endocarditis with chronic hepatitis C virus co-infection: a case report and literature review

Infective endocarditis is a rare but life-threatening condition, occasionally linked to diverse immunologic manifestations, including mixed cryoglobulinemia. This can lead to cryoglobulinemic vasculitis, which has the potential for widespread organ damage. Although some cases have highlighted the relationship between infective endocarditis and cryoglobulinemic vasculitis, no comprehensive epidemiological evaluation or optimal treatment strategies have been advanced for such a combination. We present a case of methicillin-sensitive Staphylococcus aureus infective endocarditis associated with cryoglobulinemic vasculitis and conduct a literature review to compare management and outcomes in similar cases. Our patient presented with classical Meltzer's triad and mild renal involvement. Cryoimmunofixation confirmed type III cryoglobulinemia, and serum cytokines showed elevated IL-6 levels. The differential diagnosis included infective endocarditis and chronic active hepatitis C virus infection. Rapid symptom resolution after antibiotic treatment identified infective endocarditis as the likely cause of cryoglobulinemic vasculitis. Our case and review of the literature highlight that early identification of the cause of cryoglobulinemic vasculitis is crucial for selecting appropriate treatment and preventing recurrence or morbidity.

Systematic review of case reports of antiphospholipid syndrome following infection

OBJECTIVE

The objective of this study was to conduct a systematic review of case reports documenting the development of antiphospholipid syndrome or antiphospholipid syndrome-related features after an infection.

METHODS

We searched Medline, EMBASE, Web of Science, PubMed ePubs, and The Cochrane Library - CENTRAL through March 2015 without restrictions. Studies reporting cases of antiphospholipid syndrome or antiphospholipid syndrome-related features following an infection were included.

RESULTS

Two hundred and fifty-nine publications met inclusion criteria, reporting on 293 cases. Three different groups of patients were identified; group 1 included patients who fulfilled the criteria for definitive antiphospholipid syndrome (24.6%), group 2 included patients who developed transient antiphospholipid antibodies with thromboembolic phenomena (43.7%), and group 3 included patients who developed transient antiphospholipid antibodies without thromboembolic events (31.7%). The most common preceding infection was viral (55.6%). In cases that developed thromboembolic events Human immunodeficiency and Hepatitis C viruses were the most frequently reported. Parvovirus B19 was the most common in cases that developed antibodies without thromboembolic events. Hematological manifestations and peripheral thrombosis were the most common clinical manifestations. Positive anticardiolipin antibodies were the most frequent antibodies reported, primarily coexisting IgG and IgM isotypes. Few patients in groups 1 and 2 had persistent antiphospholipid antibodies for more than 6 months. Outcome was variable with some cases reporting persistent antiphospholipid syndrome features and others achieving complete resolution of clinical events.

CONCLUSIONS

Development of antiphospholipid antibodies with all traditional manifestations of antiphospholipid syndrome were observed after variety of infections, most frequently after chronic viral infections with Human immunodeficiency and Hepatitis C. The causal relationship between infection and antiphospholipid syndrome cannot be established, but the possible contribution of various infections in the pathogenesis of antiphospholipid syndrome need further longitudinal and controlled studies to establish the incidence, and better quantify the risk and the outcomes of antiphospholipid-related events after infection.

Non HCV-related infectious cryoglobulinemia vasculitis: Results from the French nationwide CryoVas survey and systematic review of the literature

In patients with infectious cryoglobulinemia vasculitis (CryoVas) in the absence of hepatitis C virus infection, data on presentation, therapeutic management and outcome are lacking. We conducted a nationwide survey that included patients with HCV-negative CryoVas. We describe here the presentation, therapeutic management and outcome of 18 patients with non-HCV infectious CryoVas and 27 additional patients identified form a systematic review of the literature. We included 18 patients, mean age 57.9±13.5 years. Infectious causes were viral infections in 8 patients [hepatitis B virus (HBV) in 4, and cytomegalovirus, Epstein Barr virus, parvovirus B19 and human immunodeficiency virus in one case each], pyogenic bacterial infection in 6 patients, parasitic infection in 2 patients, and leprosy and candidiasis in one case each. Baseline manifestations were purpura (78%), glomerulonephritis (28%), arthralgia (28%), peripheral neuropathy (22%), skin necrosis (22%), cutaneous ulcers (17%), and myalgia (11%). Cryoglobulinemia was type II in 2/3 of cases. Most cases received specific anti-infectious therapy as first-line therapy, sometimes associated with corticosteroids, achieving sustained remission in the majority of cases. Refractory or relapsing patients, frequently related to HBV infection, showed a complete remission after rituximab in addition to antiviral therapy. In contrast, corticosteroids and/or immunosuppressive agents used in the absence of anti-infectious agents were frequently associated with refractory CryoVas. Viral and pyogenic bacterial infections represent the main causes of non-HCV infectious CryoVas. Antimicrobial therapy is commonly associated with sustained remission. Immunosuppressive agents should be considered only as a second-line option in patients with refractory vasculitis.

PCR primers for the amplification of the 16S rRNA gene of oral bacteria and for the specific identification of Actinobacillus actinomycetemcomitans

The aim of this study was to develop a PCR reaction specific to Actinobacillus actinomycetemcomitans, which targets a widely conserved gene of this bacterium. Two sets of primers were designed based on published sequences of the 16S rRNA of several microorganisms. The first set amplifies a major part of the 16S small subunit rRNA gene of several strains of bacteria commonly found in the periodontal pocket. This reaction produced a 1306 bp-long product and served as a positive control. The second set was specific to A. actinomycetemcomitans and produced a 449 bp-long product. H. aphrophilus and E. coli yielded positive results with the control primers and negative results with the A. actinomycetemcomitans-specific primers. DNA-DNA hybridization was used to validate the identify of the amplified sequences. B. cereus, which is a common contaminator in the laboratory, and human DNA did not generate PCR products in either reaction. The developed primers seen useful for the identification of A. actinomycetemcomitans strains.