scholarly journals Avidity of IgG class antibodies to Francisella tularensis in the course of tularemia in humans

2019 ◽  
pp. 43-50
Author(s):  
Waldemar Rastawicki ◽  
Karolina Śmietańska ◽  
Natalia Rokosz-Chudziak ◽  
Urszula Roguska
Keyword(s):  
Francisella Tularensis ◽  
Clinical Symptoms ◽  
Active Phase ◽  
Microbiological Diagnosis ◽  
Igg Antibodies ◽  
Negative Bacterium ◽  
Avidity Index ◽  
Serum Samples ◽  
Recent Infection ◽  
Gram Negative

Introduction: Tularemia is a highly infectious zoonotic disease caused by Gram-negative bacterium Francisella tularensis. The microbiological diagnosis of tularemia is based mainly on serological investigations. The present study was undertaken to determine the avidity of IgG class antibodies to Francisella tularensis in the course of tularemia in humans and to evaluate its value for estimation of the phase of diseases. Methods: Fifty two serum samples obtained from 40 patients with tularemia were tested by in-house ELISA in duplicate in the same plate, without and after the 0.5 h incubation with 8M urea. The age of the subjects was between 6 and 77 years. From one patient, a 9-years-old girl with oculoglandular form of tularemia, five serum samples were taken, respectively after 0.5, 1.5, 3, 6 and 12 months from the beginning of the first clinical symptoms. Results: The results of the study showed higher values of the avidity index (AI) of IgG antibodies for F. tularensis, often exceeding the value of 0.9, in children and adolescents than in adults. The examination of serum samples obtained 2-3 times in the course of tularemia from few patients did not show significant differences in the level of avidity index depending on the period of the disease. However, in five serum samples obtained from a 9-years-old girl in the different phases of tularemia the avidity index showed increasing values (0.51, 0.80, 0.92, 0.90 and 0.94, respectively). Conclusions: The avidity index of IgG may be helpful in excluding recent infection, but its usefulness in detecting an active phase of invasion requires further research.

scholarly journals A Case of Mortality Caused by Aeromonas hydrophila in Wild-Caught Red-Eyed Crocodile Skinks (Tribolonotus gracilis)

2019 ◽  
Vol 7 (1) ◽  
pp. 4 ◽  
Author(s):  
Jun Kwon ◽  
Sang Guen Kim ◽  
Sang Wha Kim ◽  
Saekil Yun ◽  
Hyoun Joong Kim ◽  
...  
Keyword(s):  
Aeromonas Hydrophila ◽  
Opportunistic Infections ◽  
Clinical Symptoms ◽  
Human Medicine ◽  
Aquatic Environments ◽  
Negative Bacterium ◽  
Severe Stress ◽  
Antimicrobial Susceptibility Test ◽  
Gram Negative ◽  
In The Wild

Aeromonas hydrophila, a Gram-negative bacterium commonly found in aquatic environments, is pathogenic to amphibians, reptiles, and mammals. In human medicine, the clinical symptoms of aeromonad infection include not only gastroenteritis but also extraintestinal infections, such as wounds, cellulitis, and septicemia, in immunocompromised and immunocompetent individuals. In this study, ten red-eyed crocodile skinks (Tribolonotus gracilis) that shared the same space were found dead 7 days after being shipped from Indonesia. The necropsy revealed A. hydrophila to be the causative agent, and the isolates were susceptible to most antibiotics, based on an antimicrobial susceptibility test. Seven virulence factors (act, ast, alt, aerA, fla, gcaT, and ahyB) considered to be associated with virulence were detected by PCR. Microscopic examination revealed several necrotic lesions and melano-macrophage centers in the tissue slides. Reptiles caught in the wild for trade experience captivity stress. Furthermore, in the winter, reptiles are easily exposed to the cold atmosphere. These stresses can negatively impact the immunity of these ectotherms, making them vulnerable to A. hydrophila infections. Therefore, to avoid such opportunistic infections and mortality following exposure to severe stress, medical care is recommended. The studies of alternatives, such as bacteriophage and bacteriocin, are needed for a preventive application.

Tularemia

2016 ◽  
Author(s):  
Alida Gertz
Keyword(s):  
Health Care ◽  
Antibiotic Resistance ◽  
Oral Administration ◽  
Supportive Care ◽  
Health Care System ◽  
Francisella Tularensis ◽  
Small Mammals ◽  
Clinical Symptoms ◽  
Gram Negative ◽  
Route Of Transmission

Tularemia, caused by the gram-negative coccobacillus Francisella tularensis, is an extremely infectious bacterial zoonosis. Symptoms depend on site of exposure; they can be nonspecific and may include fever, lymphadenopathy, ulcer or papule, and nausea/vomiting. Natural transmission occurs via small mammals, such as rabbits, or arthropod bites. IV or IM antibiotics are preferred over oral forms. Supportive care is also critical; some patients may require respiratory support. If used as a biological weapon, aerosolized F. tularensis would be the most likely route of transmission. Clinical symptoms would include those of pneumonic tularemia. In the event of a bioterrorist attack, oral administration antibiotics can be used, as the health care system may not be able to accommodate intravenous or intramuscular treatment. Antibiotic resistance should also be considered if patients deteriorate despite use of recommended antibiotics.

scholarly journals Melioidosis and the Heart: A Systematic Review

2020 ◽  
Vol 5 (3) ◽  
pp. 121
Author(s):  
Ragani Velusamy ◽  
Stephen Muhi
Keyword(s):  
Systematic Review ◽  
Quantitative Data ◽  
Burkholderia Pseudomallei ◽  
Cardiac Involvement ◽  
Clinical Presentation ◽  
Eradication Therapy ◽  
Microbiological Diagnosis ◽  
Negative Bacterium ◽  
Gram Negative ◽  
Cardiac Manifestations

Melioidosis is caused by Gram-negative bacterium Burkholderia pseudomallei. Clinical presentation can vary from pneumonia, sepsis and multi-focal abscess formation. The aim of this study was to systemically review the cardiac manifestations of melioidosis in the literature and describe their epidemiology, microbiological diagnosis and outcomes. A systematic review of the peer-reviewed literature was carried out in PubMed and Google Scholar for human melioidosis cases with cardiac involvement. Quantitative data for cases of melioidosis were obtained, including age, sex, microbiological diagnosis, treatment, and outcome. 980 articles were screened, of which 31 articles were eligible. The most common cardiac site of infection was pericarditis, followed by endocarditis and myocarditis. Over 95% of cardiac involvement occurred in males, and mortality was the lowest in pericarditis and highest in myocarditis. Valvular vegetations were all small, left-sided, and did not require surgery. Antibiotic treatment included a bactericidal induction therapy with ceftazidime or a carbapenem ± TMP-SMX, followed by eradication therapy with TMP–SMX in most patients as previously established. In conclusion, melioidosis varies in clinical presentation and is also known as a great imitator. Although cardiac involvement is rare, this is the first systematic review to summarise all cases reported in the literature to date.

scholarly journals Presence of Pili on the Surface of Francisella tularensis

2004 ◽  
Vol 72 (5) ◽  
pp. 3042-3047 ◽  
Author(s):  
Horacio Gil ◽  
Jorge L. Benach ◽  
David G. Thanassi
Keyword(s):  
Electron Microscopy ◽  
Francisella Tularensis ◽  
Vaccine Strain ◽  
Live Vaccine ◽  
Live Vaccine Strain ◽  
Negative Bacterium ◽  
Gram Negative ◽  
Schu S4 ◽  
Highly Virulent

ABSTRACT Francisella tularensis is a highly infectious gram-negative bacterium with potential for use as a bioweapon. Analysis of the F. tularensis live vaccine strain (LVS) ultrastructure by electron microscopy revealed the presence of long, thin fibers, similar in appearance to type 4 pili. The highly virulent F. tularensis Schu S4 strain was found to contain type 4 pilus genes, and we confirmed that these genes are present and expressed in the LVS.

scholarly journals Anti-HEV IgG Avidity Testing: Utility for Diagnosing Acute and Resolved Genotype 3 Infections

Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 236
Author(s):  
Claudia Minosse ◽  
Daniele Lapa ◽  
Antonio Coppola ◽  
Federica Rapagna ◽  
Gianpiero D’Offizi ◽  
...  
Keyword(s):  
False Negative ◽  
Molecular Testing ◽  
Test Results ◽  
Genotype 3 ◽  
Avidity Index ◽  
Serum Samples ◽  
Recent Infection ◽  
Assay Sensitivity ◽  
Igg Avidity ◽  
Automated Instrument

European Association of the Study of the Liver (EASL) guidelines specify HEV RNA, as well as anti-HEV IgG and IgM as positive markers for acute HEV infection. HEV RNA assay sensitivity limitations may lead to false negative test results in patients with low levels of viremia. Moreover, anti-HEV IgM positivity is not a reliable indicator for distinguishing between acute and resolved infections given the ability of this antibody to persist several months after a resolved infection. Our study aims were to assess HEV IgG avidity for diagnosing acute and resolved infections, regardless of the anti-HEV IgM serostatus, and examine assay reliability when evaluating different genotype 3 (GT3) HEV subtypes. Patient serum samples (n = 104) were tested for HEV IgG avidity by utilizing the DIA.PRO kit on a DSX automated instrument. Among patients identified with acute HEV infections, 32 were infected with GT3: GT3c (n = 5), GT3e (n = 8), 3f (n = 17) and GT3-unsubtyped (n = 2). Avidity sensitivity was 91.2% and specificity was 100%. For patients with long-lasting anti-HEV IgM persistence, an Avidity Index >70% was observed. Thus, the DIA.PRO avidity assay may be utilized to distinguish between recently acquired and resolved HEV GT3 infections. However, for equivocal results (Avidity Index > 40–70%), HEV RNA molecular testing will be required to confirm a recent infection.

scholarly journals Study of eosinophil cationic protein serum levels in patients with toxocariasis

2020 ◽  
Vol 2 (3) ◽  
pp. 178-182
Author(s):  
Eleonara Marinova Kaneva ◽  
◽  
Rumen Nenkov Harizanov ◽  
Iskra Georgieva Rainova ◽  
Iskren Tsvetkov Kaftandjiev ◽  
...  
Keyword(s):  
Eosinophil Cationic Protein ◽  
Serum Levels ◽  
Disease Stage ◽  
Confirmatory Test ◽  
Ocular Involvement ◽  
Igg Antibodies ◽  
Serum Samples ◽  
Recent Infection ◽  
Cationic Protein

Introduction: Toxocariasis is a zoonotic helminth infection with difficult diagnosis. Determination of specific IgG antibodies alone does not allow to establish the disease stage and to evaluate the treatment efficacy. Therefore it is necessary to identify additional markers that will assist the diagnosis. The purpose of our study was to identify and monitor eosinophil cationic protein (ECP) levels in patients with toxocariasis confirmed by serology and to compare our data with the literature to determine the relevance of this protein as an indicator for recent infection and the effectiveness of the therapy. Material and methods: ELISA (CUSABIO) commercial kit was used for determination of ECP concentration. Sixty serum samples were studied from individuals previously tested and confirmed for toxocariasis by the presence of specific anti-Toxocara IgG antibodies in ELISA (Toxocara IgG Rbiopharm) and the presence of specific bands in Western blot as confirmatory test (LD BIO). Twenty serum samples from clinically healthy blood donors were used as a control group. Results: The mean concentration of serum ECP in the patients with toxocariasis was significantly higher than in clinically healthy subjects. Seventy-two percent of patients affected by toxicariasis showed increased serum concentration of ECP. However, no statistically significant differences were observed in terms of age (p = 0.451) and sex (p = 0.682) of the patients or clinical form of the disease. ECP levels among patients with visceral toxocariasis were relatively higher (mean 22.99 ng / ml ± 13.16 SD) in comparison to those with ocular involvement (15.60 ng/ml ± 9.92 SD). Correlation between the presence of peripheral eosinophilia and the concentration of serum ECP was not also established. Conclusion: Data from our study give us reason to believe that serum levels of ECP could serve as an additional marker indicating recent infection, especially in patients without marked increase in the blood eosinophils.

scholarly journals Use of Recombinant Nucleoproteins in Enzyme-Linked Immunosorbent Assays for Detection of Virus-Specific Immunoglobulin A (IgA) and IgG Antibodies in Influenza Virus A- or B-Infected Patients

1998 ◽  
Vol 36 (12) ◽  
pp. 3527-3531 ◽  
Author(s):  
J. T. M. Voeten ◽  
J. Groen ◽  
D. van Alphen ◽  
E. C. J. Claas ◽  
R. de Groot ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Clinical Symptoms ◽  
Immunoglobulin A ◽  
Influenza Viruses ◽  
Igg Antibodies ◽  
Serum Samples ◽  
Influenza Virus A ◽  
Iga Antibodies ◽  
Specific Immunoglobulin ◽  
Immunosorbent Assays

The nucleoprotein genes of influenza virus A/Netherlands/018/94 (H3N2) and influenza virus B/Harbin/7/94 were cloned into the bacterial expression vector pMalC to yield highly purified recombinant influenza virus A and B nucleoproteins. With these recombinant influenza nucleoproteins, enzyme-linked immunosorbent assays (ELISAs) were developed for the detection of influenza virus A- and B-specific immunoglobulin A (IgA) and IgG serum antibodies. Serum samples were collected at consecutive time points after the onset of clinical symptoms from patients with confirmed influenza virus A or B infections. Nucleoprotein-specific IgA antibodies were detected in 41.2% of influenza virus A-infected patients and in 66.7% of influenza virus B-infected patients on day 6 after the onset of clinical symptoms. In serum samples taken on day 21 (influenza virus A-infected patients) or day 28 (influenza virus B-infected patients), nucleoprotein-specific IgA antibodies could be detected in 58.8 and 58.3% of influenza virus A- and B-infected patients, respectively. At the same time, IgG antibody rises were detected in 88.2% of influenza virus A-infected patients and in 95.8% of influenza virus B-infected patients. On comparison, hemagglutination inhibition assays detected antibody titer rises in 81.3 and 72.7% of patients infected with influenza viruses A and B, respectively. In contrast to the detection of nucleoprotein-specific IgG antibodies or hemagglutination-inhibiting antibodies, the detection of nucleoprotein-specific IgA antibodies does not require paired serum samples and therefore can be considered an attractive alternative for the rapid serological diagnosis of influenza.

scholarly journals Tularemia Goes West: Epidemiology of an Emerging Infection in Austria

2020 ◽  
Vol 8 (10) ◽  
pp. 1597 ◽  
Author(s):  
Stefanie Seiwald ◽  
Anja Simeon ◽  
Erwin Hofer ◽  
Günter Weiss ◽  
Rosa Bellmann-Weiler
Keyword(s):  
Infectious Disease ◽  
Differential Diagnosis ◽  
Francisella Tularensis ◽  
Clinical Manifestations ◽  
Zoonotic Disease ◽  
Public Institutions ◽  
Negative Bacterium ◽  
Gram Negative ◽  
Potential Host ◽  
Emerging Infection

The zoonotic disease tularemia is caused by the Gram-negative bacterium Francisella tularensis, with the two major subspecies tularensis and holarctica being responsible for infections in humans and animals. The F. tularensis subspecies holarctica is less virulent and prevalent in Europe and Asia. Over the last few centuries, few epidemic outbreaks and low numbers of infections have been registered in the eastern part of Austria, specifically in the provinces of Lower Austria, Burgenland, and Styria. The reported infections were mostly associated with hunting hares and the skinning of carcasses. Within the last decade, ticks have been identified as important vectors in Tyrol and served as first evidence for the spread of F. tularensis to Western Austria. In 2018, the pathogen was detected in hares in the provinces of Tyrol, Vorarlberg, and Salzburg. We presume that F. tularensis is now established in most regions of Austria, and that the investigation of potential host and vector animals should be spotlighted by public institutions. Tularemia in humans presents with various clinical manifestations. As glandular, ulceroglandular, and typhoidal forms occur in Austria, this infectious disease should be considered as a differential diagnosis of unknown fever.

Sign in / Sign up

Export Citation Format

Share Document