scholarly journals Immunodiagnosis of histoplasmosis in a compromised host

1978 ◽  
Vol 8 (5) ◽  
pp. 558-565
Author(s):  
G A Land ◽  
J H Foxworth ◽  
K E Smith

Three serological tests for the diagnosis of histoplasmosis were compared for sensitivity and specificity in serum from blood bank donors, patients with histoplasmosis, and infected or noninfected immunosuppressed patients. The histoplasmin latex agglutination test was positive in 9% of the normal patients, 33% of the histoplasmosis patients, and 61% of the noninfected immunosuppressed patients. Since the test is prone to many false-positive results in patients with inflammatory diseases or non-Histoplasma infections, it has limited potential as a screening test among compromised patients. Immunodiffusion and counterimmunoelectrophoresis using a mycelial antigen were found to be more sensitive than either test using a combined yeast and mycelial antigen or a pure yeast phase antigen. Counterimmunoelectrophoresis at pH 7.2 proved to be the test of choice for serodiagnosis of histoplasmosis, resolving 85% of the immunocompetent infected patients and 100% of the infected immunosuppressed patients. Results indicated that counterimmunoelectrophoresis in conjunction with immunodiffusion could be used as a screening protocol to determine infection in incoming patients in a cancer hospital.

2021 ◽  
Vol 12 ◽  
Author(s):  
Nastya Kharlamova ◽  
Nicky Dunn ◽  
Sahl K. Bedri ◽  
Svante Jerling ◽  
Malin Almgren ◽  
...  

Patients with chronic inflammatory diseases are often treated with immunosuppressants and therefore are of particular concern during the SARS-CoV-2 pandemic. Serological tests will improve our understanding of the infection and immunity in this population, unless they tests give false positive results. The aim of this study was to evaluate the specificity of SARS-Cov-2 serological assays using samples from patients with chronic inflammatory diseases collected prior to April 2019, thus defined as negative. Samples from patients with multiple sclerosis (MS, n=10), rheumatoid arthritis (RA, n=47) with or without rheumatoid factor (RF) and/or anti-cyclic citrullinated peptide antibodies (anti-CCP2) and systemic lupus erythematosus (SLE, n=10) with or without RF, were analyzed for SARS-CoV-2 antibodies using 17 commercially available lateral flow assays (LFA), two ELISA kits and one in-house developed IgG multiplex bead-based assay. Six LFA and the in-house validated IgG assay correctly produced negative results for all samples. However, the majority of assays (n=13), gave false positive signal for samples from patients with RA and SLE. This was most notable in samples from RF positive RA patients. No false positive samples were detected in any assay using samples from patients with MS. Poor specificity of commercial serological assays could possibly be, at least partly, due to interfering antibodies in samples from patients with chronic inflammatory diseases. For these patients, the risk of false positivity should be considered when interpreting results of the SARS-CoV-2 serological assays.


Cancer ◽  
1999 ◽  
Vol 86 (2) ◽  
pp. 274-281 ◽  
Author(s):  
Masahiro Kami ◽  
Yoshinobu Kanda ◽  
Seishi Ogawa ◽  
Shin-ichiro Mori ◽  
Yuji Tanaka ◽  
...  

2020 ◽  
Author(s):  
Nastya Kharlamova ◽  
Nicky Dunn ◽  
Sahl K Bedri ◽  
Svante Jerling ◽  
Malin Almgren ◽  
...  

AbstractObjectivesPatients with chronic inflammatory diseases are often treated with immunosuppressants and therefore are of particular concern during the SARS-CoV-2 pandemic. Serological tests will improve our understanding of the infection and immunity in this population, unless the tests give false positive results. The aim of this study was to evaluate the specificity of SARS-Cov-2 serological assays with samples from patients with chronic inflammatory diseases collected before April 2019, thus defined as negative.MethodsSamples from patients with multiple sclerosis (MS, n=10), rheumatoid arthritis (RA, n=47) with or without rheumatoid factor (RF) and/or anti-cyclic citrullinated peptide antibodies (anti-CCP2) and RF +/- systemic lupus erythematosus (SLE, n=10), were tested with 17 commercially available lateral flow assays (LFA), two ELISA kits and one in-house developed multiplex bead-based assay.ResultsSix LFA and the in-house IgG assay gave the correct negative results for all samples. However, the majority of assays (n=13), gave false positive signal with samples from patients with RA and SLE. This was most notable in RF positive RA samples. MS samples did not give any false positive in any of the assays.ConclusionThe majority of the verified serological assays were sensitive to interfering antibodies in samples from patients with chronic inflammatory diseases and therefore may have poor specificity in this context. For these patients, the risk of false positivity should be considered when interpreting results of the SARS-CoV-2 serological assays.


2019 ◽  
Vol 29 (3) ◽  
pp. 213-221 ◽  
Author(s):  
L Alvela-Suarez ◽  
J Campos ◽  
I Carballo ◽  
J Gomez-Rial ◽  
C Vidal ◽  
...  

Author(s):  
L Alvela-Suarez ◽  
J Campos ◽  
I Carballo ◽  
J Gomez-Rial ◽  
M Lombardero ◽  
...  

2018 ◽  
Vol 72 ◽  
pp. 1162-1178
Author(s):  
Aleksandra Lewandowicz-Uszyńska ◽  
Piotr Naporowski ◽  
Gerard Pasternak ◽  
Danuta Witkowska

The human immune system’s response to infection is closely related with the type of pathogen. First, a rapid, metabolically inexpensive and non-specific innate immunity is induced, then a specific acquired immunity is activated. In bacterial infections caused by intracellular pathogens, the main role is played by cellular response. In infections caused by bacterial extracellular pathogens, a crucial role is played by antibodies. The clinical symptoms of bacterial and viral infections very often are similar, which is why diagnosing them based only on medical history and physical examination is insufficient. To identify the etiological factors of infections differentiating media, biochemical tests, molecular methods and serological tests are used. The detection of microorganisms or their genetic material can be performed within a short time after the occurrence of an infection. The detection of antibodies is possible only in the appropriate time called the serological window. In a serological diagnostic of infections there are problems with an appropriate interpretation of obtained results. Cross-reactivity can give false positive results for the diagnosis of Chlamydophila pneumonia infection. The problem with the detection of Borrelia burgdorferi infection can be caused by a simultaneous coinfection with different spirochetes, syphilis, mononucleosis or HIV. In serological diagnostics of bacterial infections, the administration of antibiotics to patients before taking serum samples can be responsible for false negative results. Another reason for such results can be a weak humoral response in infected patients. In viral infections, false positive results can be caused by a coinfection of different viruses, especially from the same family or by bacterial or protozoal coinfections or by autoimmune diseases. False-negative results in viral infections often are caused by the early phase of an infection. To properly recognize an etiological factor of infection it is necessary to use an appropriate method, precision of test and collect samples at the appropriate time.


2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Vanessa J. T. Seran ◽  
Billy J. Kepel ◽  
Fatimawali .

Abstract: Toxoplasmosis is a disease caused by Toxoplasma gondii in humans and also in animals. Toxoplasma gondii infection is widespread in the world, about 20-90% of the populations have been exposed to this parasite, and most take place without showing specific symptoms. The purpose of this study was to determine the seroepidemiology of toxoplasmosis among the villagers of kumu in district minahasa on 2015. This study was a cross sectional descriptive study. The study population was Kumu Village community. This study using blood specimens to be tested by latex agglutination test and interviews to determine the distribution of toxoplasmosis is based on risk factors. Seropositive obtained if agglutination occurs on the results of serological tests. Respondents consisted of 20 (90.90%) females and 2 (9.10%) men. The results showed 11 (50%) of respondents has toxoplasma seropositivity were distributed by age, sex, level of education, occupation, diet, hygiene, exposure to dogs, exposure to cats, and a history of miscarriage.Keywords: latex agglutination test, parasites, seropositivity, toxoplasma gondiiAbstrak: Toksoplasmosis merupakan penyakit yang disebabkan oleh Toxoplasma gondii pada manusia dan juga pada hewan. Infeksi Toxoplasma gondii tersebar luas di dunia, sekitar 20-90% populasi dunia pernah terpapar parasit ini, dan sebagian besar berlangsung tanpa menunjukkan gejala yang spesifik. Tujuan penelitian ini adalah untuk mengetahui seroepidemiologi toksoplasmosis pada masyarakat di Desa Kumu Kabupaten Minahasa tahun 2015. Penelitian ini merupakan penelitian deskriptif cross sectional. Populasi penelitian ini adalah masyarakat Desa Kumu. Penelitian ini menggunakan spesimen darah untuk diuji dengan uji aglutinasi lateks dan hasil wawancara untuk mengetahui distribusi toksoplasmosis berdasarkan faktor resiko. Seropositif didapat bila terjadi aglutinasi pada hasil tes serologis. Responden terdiri dari 20 (90,90%) wanita dan 2 (9,10%) pria. Hasil penelitian menunjukkan 11 (50%) responden seropositif toksoplasmosis yang terdistribusi berdasarkan umur, jenis kelamin, tingkat pedidikan, pekerjaan, pola makan, higienitas, paparan anjing, paparan kucing, dan riwayat keguguran.Kata kunci: uji aglutinasi lateks, parasit, seropositif, toxoplasma gondii


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