scholarly journals Salmonella enterica Serovar Typhi-Specific Immunoglobulin A Antibody Responses in Plasma and Antibody in Lymphocyte Supernatant Specimens in Bangladeshi Patients with Suspected Typhoid Fever

2009 ◽  
Vol 16 (11) ◽  
pp. 1587-1594 ◽  
Author(s):  
Alaullah Sheikh ◽  
M. Saruar Bhuiyan ◽  
Farhana Khanam ◽  
Fahima Chowdhury ◽  
Amit Saha ◽  
...  
Keyword(s):  
Typhoid Fever ◽  
Salmonella Enterica ◽  
Point Of Care ◽  
Immunoglobulin A ◽  
Unknown Origin ◽  
Epidemiological Studies ◽  
Peripheral Blood Lymphocytes ◽  
Time Of Presentation ◽  
Antibody Levels ◽  
Difficult Cases

ABSTRACTMany currently available diagnostic tests for typhoid fever lack sensitivity and/or specificity, especially in areas of the world where the disease is endemic. In order to identify a diagnostic test that better correlates with typhoid fever, we evaluated immune responses toSalmonella entericaserovar Typhi (serovar Typhi) in individuals with suspected typhoid fever in Dhaka, Bangladesh. We enrolled 112 individuals with suspected typhoid fever, cultured day 0 blood for serovar Typhi organisms, and performed Widal assays on days 0, 5, and 20. We harvested peripheral blood lymphocytes and analyzed antibody levels in supernatants collected on days 0, 5, and 20 (using an antibody-in-lymphocyte-supernatant [ALS] assay), as well as in plasma on these days. We measured ALS reactivity to a serovar Typhi membrane preparation (MP), a formalin-inactivated whole-cell preparation, and serovar Typhi lipopolysaccharide. We measured responses in healthy Bangladeshi, as well as in Bangladeshi febrile patients with confirmed dengue fever or leptospirosis. We categorized suspected typhoid fever individuals into different groups (groups I to V) based on blood culture results, Widal titer, and clinical features. Responses to MP antigen in the immunoglobulin A isotype were detectable at the time of presentation in the plasma of 81% of patients. The ALS assay, however, tested positive in all patients with documented or highly suspicious typhoid, suggesting that such a response could be the basis of improved diagnostic point-of-care-assay for serovar Typhi infection. It can be important for use in epidemiological studies, as well as in difficult cases involving fevers of unknown origin.

scholarly journals Fully automated point-of-care differential diagnosis of acute febrile illness

2021 ◽  
Vol 15 (2) ◽  
pp. e0009177
Author(s):  
Sebastian Hin ◽  
Benjamin Lopez-Jimena ◽  
Mohammed Bakheit ◽  
Vanessa Klein ◽  
Seamus Stack ◽  
...  
Keyword(s):  
Salmonella Enterica ◽  
Magnetic Particles ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Febrile Illness ◽  
Unknown Origin ◽  
Cold Chain ◽  
Small Scale ◽  
Clinical Sensitivity ◽  
Parasitic Pathogens

Background In this work, a platform was developed and tested to allow to detect a variety of candidate viral, bacterial and parasitic pathogens, for acute fever of unknown origin. The platform is based on a centrifugal microfluidic cartridge, the LabDisk (“FeverDisk” for the specific application), which integrates all necessary reagents for sample-to-answer analysis and is processed by a compact, point-of-care compatible device. Methodology/Principal findings A sample volume of 200 μL per FeverDisk was used. In situ extraction with pre-stored reagents was achieved by bind-wash-elute chemistry and magnetic particles. Enzymes for the loop-mediated isothermal amplification (LAMP) were pre-stored in lyopellet form providing stability and independence from the cold chain. The total time to result from sample inlet to read out was 2 h. The proof-of-principle was demonstrated in three small-scale feasibility studies: in Dakar, Senegal and Khartoum, Sudan we tested biobanked samples using 29 and 9 disks, respectively; in Reinfeld, Germany we tested spiked samples and analyzed the limit of detection using three bacteria simultaneously spiked in whole blood using 15 disks. Overall during the three studies, the FeverDisk detected dengue virus (different serotypes), chikungunya virus, Plasmodium falciparum, Salmonella enterica Typhi, Salmonella enterica Paratyphi A and Streptococcus pneumoniae. Conclusions/Significance The FeverDisk proved to be universally applicable as it successfully detected all different types of pathogens as single or co-infections, while it also managed to define the serotype of un-serotyped dengue samples. Thirty-eight FeverDisks at the two African sites provided 59 assay results, out of which 51 (86.4%) were confirmed with reference assay results. The results provide a promising outlook for future implementation of the platform in larger prospective clinical studies for defining its clinical sensitivity and specificity. The technology aims to provide multi-target diagnosis of the origins of fever, which will help fight lethal diseases and the incessant rise of antimicrobial resistance.

scholarly journals Typhoid Fever Associated with Acute Appendicitis Caused by an H1-j Strain of Salmonella enterica Serotype Typhi

2005 ◽  
Vol 43 (3) ◽  
pp. 1470-1472 ◽  
Author(s):  
S. K. P. Lau ◽  
P. C. Y. Woo ◽  
C. Y. F. Chan ◽  
W.-L. Woo ◽  
G. K. S. Woo ◽  
...  
Keyword(s):  
Acute Appendicitis ◽  
Typhoid Fever ◽  
Salmonella Enterica

scholarly journals Potential of Immunoglobulin A to Prevent Allergic Asthma

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Anouk K. Gloudemans ◽  
Bart N. Lambrecht ◽  
Hermelijn H. Smits
Keyword(s):  
Allergic Asthma ◽  
Immunoglobulin A ◽  
Bronchial Hyperresponsiveness ◽  
Airway Disease ◽  
Epidemiological Studies ◽  
Allergic Airway Disease ◽  
Secretory Iga ◽  
Th2 Cells ◽  
Lower Airway

Allergic asthma is characterized by bronchial hyperresponsiveness, a defective barrier function, and eosinophilic lower airway inflammation in response to allergens. The inflammation is dominated by Th2 cells and IgE molecules and supplemented with Th17 cells in severe asthma. In contrast, in healthy individuals, allergen-specific IgA and IgG4 molecules are found but no IgE, and their T cells fail to proliferate in response to allergens, probably because of the development of regulatory processes that actively suppress responses to allergens. The presence of allergen-specific secretory IgA has drawn little attention so far, although a few epidemiological studies point at a reverse association between IgA levels and the incidence of allergic airway disease. This review highlights the latest literature on the role of mucosal IgA in protection against allergic airway disease, the mechanisms described to induce secretory IgA, and the role of (mucosal) dendritic cells in this process. Finally, we discuss how this information can be used to translate into the development of new therapies for allergic diseases based on, or supplemented with, IgA boosting strategies.

scholarly journals Highly Resistant Salmonella enterica Serovar Typhi with a NovelgyrAMutation Raises Questions about the Long-Term Efficacy of Older Fluoroquinolones for Treating Typhoid Fever

2012 ◽  
Vol 56 (5) ◽  
pp. 2761-2762 ◽  
Author(s):  
Kanika Deshpande Koirala ◽  
Duy Pham Thanh ◽  
Sudeep Dhoj Thapa ◽  
Amit Arjyal ◽  
Abhilasha Karkey ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Typhoid Fever ◽  
Treatment Failure ◽  
Salmonella Enterica ◽  
Systemic Infection ◽  
Resistant Isolate ◽  
Content Type ◽  
Salmonella Enterica Serovar Typhi ◽  
Term Efficacy

ABSTRACTAs a consequence of multidrug resistance, clinicians are highly dependent on fluoroquinolones for treating the serious systemic infection typhoid fever. While reduced susceptibility to fluoroquinolones, which lessens clinical efficacy, is becoming ubiquitous, comprehensive resistance is exceptional. Here we report ofloxacin treatment failure in typhoidal patient infected with a novel, highly fluoroquinolone-resistant isolate ofSalmonella entericaserovar Typhi. The isolation of this organism has serious implications for the long-term efficacy of ciprofloxacin and ofloxacin for typhoid treatment.

scholarly journals A SYSTEMATIC EVALUATION OF RAPID DOT-EIA, BLOOD CULTURE AND WIDAL TEST IN THE DIAGNOSIS OF TYPHOID FEVER

2013 ◽  
Vol 03 (01) ◽  
pp. 21-24 ◽  
Author(s):  
H. Sanjeev ◽  
Sweetha Nayak ◽  
Pai Asha K. B. ◽  
Rai Rekha ◽  
Vimal Karnaker ◽  
...  
Keyword(s):  
Blood Culture ◽  
Typhoid Fever ◽  
Gold Standard ◽  
Salmonella Enterica ◽  
Diagnostic Yield ◽  
Far East ◽  
Health Care Facilities ◽  
Systematic Evaluation ◽  
Widal Test ◽  
South Central

Abstract Background: Typhoid fever, caused by Salmonella enterica serotype Typhi, is endemic in the Indian sub-continent including Bangladesh, South-east and Far-east Asia, Africa and South Central America. The disease can occur in all age group with highest incidence among children. Blood culture is regarded as the gold standard for diagnosis and carry 70-75% diagnostic yield in the first week of illness. However, this requires laboratory equipment and technical training that are beyond the means of most primary health care facilities in the developing world. Typhidot is a rapid dot-enzyme immune assay (EIA), which detects IgG and IgM antibodies to a specific 50 kD outer membrane protein (OMP) antigen of Salmonella enterica serotype Typhi. Typhidot becomes positive as early as in the first week of fever. The results can be visually interpreted and is available within one hour. Materials and method: Fifty blood samples, collected aseptically from patients clinically diagnosed of Typhoid fever, were evaluated by blood culture, Widal test and Typhidot. Results: Of the 50 patients, 33 (66%) were positive by blood culture. Widal test was positive in 33(66%) patients which included 26 in blood culture positive patients and 7 in blood culture negative patients. Typhidot was positive in 37 (74%) patients. Thus, in comparison to the gold standard test i:e blood culture, Typhidot and Widal test had sensitivity and specificity of 100% & 76% and 78.78% & 58.82% respectively. Conclusion: Typhidot is found to have high sensitivity and good specificity and could be applied as a good alternate in resource poor nation. Further, it is simple to perform, reliable when compared to Widal test, and rapid, with results being available in one hour when compared to 48 hours for blood culture and 18 hours for Widal test.

scholarly journals Serologic and Molecular Diagnosis of Anaplasma platys and Ehrlichia canis Infection in Dogs in an Endemic Region

Pathogens ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 488
Author(s):  
Bianca Lara ◽  
Anne Conan ◽  
Mary Anna Thrall ◽  
Jennifer K. Ketzis ◽  
Gillian Carmichael Branford ◽  
...  
Keyword(s):  
Early Stage ◽  
Point Of Care ◽  
False Negative ◽  
Ehrlichia Canis ◽  
Test Results ◽  
Anaplasma Platys ◽  
Endemic Region ◽  
Life Threatening ◽  
Improve Patient Management ◽  
Antibody Levels

Anaplasma platys and Ehrlichia canis are obligate intracellular, tick-borne rickettsial pathogens of dogs that may cause life-threatening diseases. In this study, we assessed the usefulness of PCR and a widely used commercial antibody-based point-of-care (POC) test to diagnose A. platys and E. canis infection and updated the prevalence of these pathogens in dogs inhabiting the Caribbean island of Saint Kitts. We detected A. platys in 62/227 (27%), E. canis in 84/227 (37%), and the presence of both in 43/227 (19%) of the dogs using PCR. POC testing was positive for A. platys in 53/187 (28%), E. canis in 112/187 (60%), and for both in 42/187 (22%) of the samples tested. There was only a slight agreement between A. platys PCR and POC test results and a fair agreement for E. canis PCR and POC test results. Our study suggests that PCR testing may be particularly useful in the early stage of infection when antibody levels are low or undetectable, whereas, POC test is useful when false-negative PCR results occur due to low bacteremia. A combination of PCR and POC tests may increase the ability to diagnose A. platys and E. canis infection and consequently will improve patient management.

Persistence of Antibodies to 2 Virus-Like Particle Norovirus Vaccine Candidate Formulations in Healthy Adults: 1-Year Follow-up With Memory Probe Vaccination

2019 ◽  
Vol 220 (4) ◽  
pp. 603-614 ◽  
Author(s):  
Robert L Atmar ◽  
Frank Baehner ◽  
Jakob P Cramer ◽  
Eric Lloyd ◽  
James Sherwood ◽  
...  
Keyword(s):  
Vaccine Candidate ◽  
Immunoglobulin A ◽  
Primary Vaccination ◽  
Immune Memory ◽  
Virus Like Particle ◽  
Memory Probe ◽  
Antibody Titers ◽  
Antibody Levels ◽  
With Memory

AbstractBackgroundWe previously reported the tolerability and immunogenicity 1 month after intramuscular administration of 2 bivalent virus-like particle (VLP)–based candidate norovirus vaccine formulations in adults. We now describe the persistence of immunity and responses to a memory probe vaccination 1 year later.MethodsA total of 454 healthy men and women aged 18–49 years in 3 equal groups received placebo (saline) or 15/50 or 50/50 vaccine formulations (ie, 15 or 50 µg of GI.1 genotype VLPs, respectively, and 50 µg of GII.4c VLPs) with MPL and Al(OH)3. Immunogenicity and safety were assessed up to day 365, when 351 participants received a memory probe vaccination of 15 µg each of GI.1 and GII.4c VLPs with Al(OH)3.ResultsNo safety signals were detected up to 1 year after the first vaccination. Pan-immunoglobulin, immunoglobulin A, and histo-blood group antigen–blocking (HBGA) antibody levels among vaccinees waned but remained higher than levels before vaccination and levels in placebo recipients on days 180 and 365. Memory probe vaccination increased all antibody titers. Levels of HBGA antibodies to GI.1 but not GII.4c were higher after the first vaccination in candidate vaccine groups, compared with those in the placebo group.ConclusionLevels of antibodies to both candidate norovirus VLP formulations persisted above baseline levels for at least 1 year after primary vaccination. HBGA-blocking responses to the memory probe for GI.1 but not GII.4c displayed characteristics of immune memory.Clinical Trials RegistrationNCT02142504.

Sign in / Sign up

Export Citation Format

Share Document