FALSE NEGATIVE WESTERN BLOT OBSCURING A CASE OF LYME CARDITIS

Abstract In suspected cases of disseminated intravascular coagulation, concurrent elevation of both fibrin(ogen) degradation products (FDPs) and D-dimer levels aids in confirming the diagnosis. This pattern of results reflects the action of plasmin proteolysis of cross-linked fibrin polymers as well as fibrinogen. We report the case of a patient with human immunodeficiency virus (HIV) and Castleman disease who presented with a high-positive D-dimer level and a negative FDP level in the course of a workup for disseminated intravascular coagulation. This finding suggested the possibility of either a false-positive D-dimer or a false-negative FDP level. To investigate the former, a Western blot was performed on the patient's serum to determine the presence of the D-dimer. No D-dimer band was visualized on the Western blot, confirming the false-positive nature of the D-dimer result. Insufficient quantity of patient serum, however, prevented further investigation into the etiology of this result. The false-positive D-dimer result is likely attributable to interference caused by the patient's Castleman disease–associated monoclonal gammopathy, a phenomenon that has been reported in other immunoassays. As the development of lymphoproliferative disorders is especially common within the HIV population, and hypergammaglobulinemia in Castleman disease is particularly common, clinicians should be aware of this phenomenon when the laboratory findings do not fit the clinical picture. Although it is rare, recognition of potential paraprotein interference in immunoassays will help avoid undertreatment or overtreatment of patients based on erroneous laboratory results.

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Combined Use of Indirect ELISA and Western Blotting with Recombinant Hepatocellular Carcinoma-Associated Antigen 59 Is a Potential Immunodiagnostic Tool for the Detection of Prepatent Haemonchus contortus Infection in Goat

Animals ◽

10.3390/ani9080548 ◽

2019 ◽

Vol 9 (8) ◽

pp. 548 ◽

Cited By ~ 7

Author(s):

Muhammad Ali-ul-Husnain Naqvi ◽

Sana Zahra Naqvi ◽

Muhammad Ali Memon ◽

Kalibixiati Aimulajiang ◽

Muhammad Haseeb ◽

...

Keyword(s):

Western Blot ◽

Western Blotting ◽

Haemonchus Contortus ◽

Indirect Elisa ◽

Fasciola Hepatica ◽

False Negative ◽

Cross Reactivity ◽

Enzyme Linked Immunosorbent Assay ◽

Serum Samples ◽

Combined Use

Haemonchus contortus is recognized as one of the important health problems in small ruminants, leading to reduced production and economic loss for farmers worldwide. Prepatent diagnosis of H. contortus infection is crucial to improve control strategies as this helminth may remove up to one-fifth of total erythrocytes and may cause anemia, edema, diarrhea, and ultimately death in young animals. In this study, one of the excretory and secretory products, rHc-HCA59, was purified and used as antigen to detect specific antibodies in H. contortus infected goats during prepatent stage of infection using indirect enzyme linked immunosorbent assay (ELISA) as screening test. All goats (n = 38) were housed indoor, experimentally infected with 8000 infective larvae (L3) of H. contortus, and serum samples were collected prior to infection and at 14th day of infection. Immunoblotting was performed to confirm the results of indirect ELISA, evaluate the cross reactivity against rHc-HCA59 in sera of most common co-infecting parasites and rectify the false negative samples. Furthermore, three different batches of rHc-HCA59 were produced to evaluate the repeatability of ELISA. No eggs were detected in feces of all goats collected at 7th and 14th day of infection but, H. contortus eggs were detected at 21 days post infection in the feces. Indirect ELISA performed in this study showed 87% sensitivity and 100% specificity. The western blot analysis confirmed immunoreactivity in serum samples which scored positive in indirect ELISA and recognized the samples as negative which had OD450 lower than negative cut-off value in indirect ELISA. Furthermore, all false negative sera (n = 5) that had OD450 value between positive and negative cut-off value in rHc-HCA59 based ELISA were clearly positive in western blot. Moreover, no cross-reactivity was detected in ELISA and western blotting against rHc-HCA59 in positive sera of Toxoplasma gondii, Fasciola hepatica, and Trichinella spiralis. The results of this study concluded that combined use of indirect ELISA and western blotting with rHc-HCA59 is a potential immunodiagnostic tool for the detection of H. contortus infection during prepatent period in goats.

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Mycoplasma agassizii Strain Variation and Distinct Host Antibody Responses Explain Differences between Enzyme-Linked Immunosorbent Assays and Western Blot Assays

Clinical and Vaccine Immunology ◽

10.1128/cvi.00215-10 ◽

2010 ◽

Vol 17 (11) ◽

pp. 1739-1745 ◽

Cited By ~ 9

Author(s):

Lori D. Wendland ◽

Paul A. Klein ◽

Elliott R. Jacobson ◽

Mary B. Brown

Keyword(s):

Western Blot ◽

Goodness Of Fit ◽

False Negative ◽

Well Being ◽

Management Decision ◽

Enzyme Linked Immunosorbent Assay ◽

Upper Respiratory Tract ◽

Strain Variation ◽

Serum Samples ◽

Mycoplasma Agassizii

ABSTRACT The precarious status of desert (Gopherus agassizii) and gopher (G. polyphemus) tortoises has resulted in conservation efforts that now include health assessment as an important component of management decision-making. Mycoplasmal upper respiratory tract disease (URTD) is one of very few diseases in chelonians for which comprehensive and rigorously validated diagnostic tests exist. In this study, serum samples obtained from eight Gopherus tortoises documented at necropsy to (i) be enzyme-linked immunosorbent assay (ELISA) seropositive using the PS6 antigen, (ii) be infected with Mycoplasma agassizii as indicated by direct isolation of the pathogen from the respiratory surfaces, and (iii) have histological lesions of mycoplasmal URTD were used to evaluate four distinct clinical isolates of M. agassizii as antigens for ELISA and Western blot analyses. Each animal sample reacted in the Western blot with its homologous M. agassizii strain, but recognition of heterologous M. agassizii strains was variable. Further, individual animals varied significantly with respect to the specific proteins recognized by the humoral immune response. An additional 114 Gopherus serum samples were evaluated using ELISA antigens prepared from the four distinct M. agassizii strains; A 405 values were significantly correlated (r 2 goodness of fit range, 0.708 to 0.771; P < 0.0001) for all antigens tested. The results confirm that strain variation is responsible for the observed differences between Western blot binding patterns. Thus, reliance on a single M. agassizii strain as an antigen in Western blot assays may provide false-negative results. This could have adverse consequences for the well-being of these environmentally sensitive hosts if false-negative animals were relocated to sites consisting of true-negative populations.

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Acute Human Immunodeficiency Virus Infection: False-Negative ELISA in a Patient with Viremia and a Positive Western Blot Test

The Journal of Infectious Diseases ◽

10.1093/infdis/160.1.160 ◽

1989 ◽

Vol 160 (1) ◽

pp. 160-161 ◽

Cited By ~ 4

Author(s):

B. P. Griffith ◽

D. Ferguson ◽

J. W. Mellors

Keyword(s):

Human Immunodeficiency Virus ◽

Virus Infection ◽

Human Immunodeficiency Virus Infection ◽

Western Blot ◽

False Negative ◽

Western Blot Test ◽

Immunodeficiency Virus

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A Patient with AIDS and a False Negative HIV Western Blot

Infection Control ◽

10.1017/s0195941700067527 ◽

1987 ◽

Vol 8 (12) ◽

pp. 490-491

Author(s):

Jack Stapleton ◽

Judith Britz ◽

James R. Carlson ◽

James Folds

Keyword(s):

Western Blot ◽

False Negative

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Evaluation of the Aspergillus Western Blot IgG Kit for Diagnosis of Chronic Aspergillosis

Journal of Clinical Microbiology ◽

10.1128/jcm.02690-14 ◽

2014 ◽

Vol 53 (1) ◽

pp. 248-254 ◽

Cited By ~ 22

Author(s):

A. Oliva ◽

P. Flori ◽

C. Hennequin ◽

J.-C. Dubus ◽

M. Reynaud-Gaubert ◽

...

Keyword(s):

Western Blot ◽

False Negative ◽

Allergic Bronchopulmonary Aspergillosis ◽

Reference Method ◽

Diagnostic Odds Ratio ◽

Antibody Detection ◽

Serum Samples ◽

Content Type ◽

Current Reference ◽

Clinical Presentations

Immunoprecipitin detection (IPD) is the current reference confirmatory technique for anti-Aspergillusantibody detection; however, the lack of standardization is a critical drawback of this assay. In this study, we evaluated the performance of theAspergillusWestern blot (Asp-WB) IgG kit (LDBio Diagnostics, Lyon, France), a recently commercialized immunoblot assay for the diagnosis of various clinical presentations of chronic aspergillosis. Three hundred eight serum samples from 158 patients with aspergillosissensu lato(s.l.) were analyzed. More specifically, 267 serum samples were derived from patients withAspergillusdisease, including 89 cases of chronic pulmonary aspergillosis, 10 of aspergilloma, and 32 of allergic bronchopulmonary aspergillosis, while 41 samples were from patients withAspergilluscolonization, including 15 cystic fibrosis (CF) and 12 non-CF patients. For blood donor controls, theAsp-WB specificity was 94%, while the kit displayed a sensitivity for the aspergillosis s.l. diagnosis of 88.6%, with a diagnostic odds ratio (DOR) of 119 (95% confidence interval [CI], 57 to 251). The DOR values were 185.22 (95% CI,78.79 to 435.45) and 43.74 (95% CI, 15.65 to 122.20) for the diagnosis ofAspergillusdisease andAspergilluscolonization, respectively. Among the patients, the sensitivities of theAsp-WB in the diagnosis ofAspergilluscolonization were 100% and 41.7% in CF and non-CF patients, respectively. TheAsp-WB yielded fewer false-negative results than did IPD. In conclusion, theAsp-WB kit performed well for the diagnosis of various clinical presentations of aspergillosis in nonimmunocompromised patients, with an enhanced standardization and a higher sensitivity than with IPD, which is the current reference method.

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Development of a confirmatory enzyme-linked immunosorbent assay for HIV-1 antibodies.

Clinical Chemistry ◽

10.1093/clinchem/35.6.946 ◽

1989 ◽

Vol 35 (6) ◽

pp. 946-952 ◽

Cited By ~ 8

Author(s):

C S Chiang ◽

T Grove ◽

M Cooper ◽

J Cuan ◽

A Kowalski ◽

...

Keyword(s):

Western Blot ◽

Immunosorbent Assay ◽

False Negative ◽

Microtiter Plate ◽

Enzyme Linked Immunosorbent Assay ◽

Western Blot Assay ◽

Protein Coding ◽

Negative Results ◽

Immunodeficiency Syndrome ◽

Hiv 1

Abstract We subcloned six discrete protein-coding regions representing the gag (Kp24 and Kp55), env (Kp41, Kp120N, and Kp120CC), and pol (Kp66/31) gene products of the human immunodeficiency virus type 1 (HIV-1) and expressed them in Escherichia coli as fusion proteins with the first 56 residues of galactokinase. An enzyme-linked immunosorbent assay for confirming the presence of HIV-1 antibodies was developed by coating the six purified antigens on individual wells of a microtiter plate (the HIVAGEN assay). This assay yielded no false-negative results and fewer indeterminate results than the Western blot assay for 143 specimens from patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC). Analysis of 1016 specimens from seronegative donors by the HIVAGEN assay yielded no false-positive results, and the rate of indeterminate results was substantially lower than for the Western blot assay. The HIVAGEN assay is well suited for routine confirmation of the presence of HIV-1 antibodies because it is objective, quantitative, rapid, precise, and readily automatable.

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