scholarly journals Screening for Interference in Immunoassays

2003 ◽  
Vol 49 (7) ◽  
pp. 1163-1169 ◽  
Author(s):  
Jane F Emerson ◽  
Gilda Ngo ◽  
Scott S Emerson
Keyword(s):  
Specific Antigen ◽  
Clinical History ◽  
Negative Control ◽  
Thyroid Stimulating Hormone ◽  
Serial Dilution ◽  
Positive Outcomes ◽  
Screening Techniques ◽  
Discrepant Result ◽  
Nonlinear Responses ◽  
Mouse Antibody

Abstract Background: The presence of interfering substances in patient samples submitted for immunoassay cannot be reliably anticipated. We therefore evaluated three interference screening techniques and estimated the prevalence of interfering substances as defined by positive outcomes with these protocols. Methods: We evaluated 160 samples for the presence of substances that may interfere with four immunoassays (40 samples for each): thyroid-stimulating hormone, prostate-specific antigen, β-human chorionic gonadotropin, and cortisol. Interference was defined by nonlinear responses with serial dilution, discrepant results after pretreatment with heterophile blocking reagent (HBR), and positive reactions on a mouse-antibody-negative control reaction (Tandem ICON® ImmunoConcentration HCG). Criteria for declaring significant discrepant results were based on a Z-score computed using the assay CV. The McNemar test was used to compare the prevalence of discrepancies across the three screening techniques. The association between type of immunoassay and prevalence of discrepant results was determined by a modified Pearson χ2 statistic. Results: Five of the 160 samples [3.1%; 95% confidence interval (CI), 1.0–7.1%] screened positive with the ICON. Seventy-two of the 148 samples with informative serial dilutions (48.6%; 95% CI, 40.4–57.0%) had at least one discrepant result at higher dilutions. After pretreatment with HBR, 53 of the 140 samples (38%; 95% CI, 29.8–46%) were discrepant. Only 48 of the 140 samples with informative measurements for all three screening techniques (34%; 95% CI, 26–43%) were negative by all three. The prevalence of positive screens varied significantly by type of immunoassay (P <0.0001) for both HBR and serial dilution. Only 3% (0.8–7%) of the samples tested with HBR showed a change from normal to abnormal or the reverse after treatment. Conclusions: Introducing a protocol based on any of these three techniques into the immunochemistry laboratory to prescreen for interfering substances is not warranted. The evaluation of specimens for the presence of interfering anti-animal antibodies should be reserved for cases in which clinical history or suspicious results indicate the need.

Detection of Rhizopus-specific antigen in human and murine serum and bronchoalveolar lavage

2020 ◽  
Vol 58 (7) ◽  
pp. 958-964
Author(s):  
Wataru Shibata ◽  
Mamiko Niki ◽  
Kanako Sato ◽  
Hiroki Fujimoto ◽  
Koichi Yamada ◽  
...  
Keyword(s):  
Bronchoalveolar Lavage ◽  
Diagnostic Method ◽  
Signal Sequence ◽  
Specific Antigen ◽  
Invasive Pulmonary Aspergillosis ◽  
Clinical Decision ◽  
Lavage Fluid ◽  
Negative Control ◽  
Enzyme Linked Immunosorbent Assay ◽  
Elisa System

Abstract Mucormycosis is a deep-seated fungal infection that mainly develops in patients with severe immunodeficiencies such as those with malignant hematological diseases. Despite poor prognosis, there is no reliable and minimally invasive diagnostic method—such as serodiagnosis—for making a clinical decision regarding the condition. As early diagnosis and early treatment improve the prognosis of mucormycosis, the development of a sensitive early diagnostic method is important. We had previously identified a Rhizopus-specific antigen (RSA) by signal sequence trapping and retrovirus-mediated expression (SST-REX), and evaluated its utility as a diagnostic antigen by constructing a sandwich enzyme-linked immunosorbent assay (ELISA) system to detect serum RSA levels in inoculated mice. In this study, we used the RSA-specific rabbit monoclonal antibodies generated by novel hybridoma technology to improve the sensitivity of the ELISA system. We observed an increase in serum and bronchoalveolar lavage fluid (BALF) levels of RSA in mouse model 1 day after inoculation, suggesting that this newly developed monoclonal antibody-based ELISA system may be useful for the diagnosis of mucormycosis in the early stages of infection. In addition, we measured RSA levels in human serum and BALF, and found that serum RSA level was higher in mucormycosis patients (15.1 ng/ml) than that in invasive pulmonary aspergillosis patients (0.53 ng/ml) and the negative control (0.49 ng/ml). Our results suggest that RSA may be a powerful tool for the diagnosis of pulmonary mucormycosis, and its differentiation from other deep-seated mycoses such as aspergillosis.

scholarly journals Prevention of canine ocular thelaziosis (Thelazia callipaeda) with a combination of milbemycin oxime and afoxolaner (Nexgard Spectra®) in endemic areas in France and Spain

Parasite ◽  
2019 ◽  
Vol 26 ◽  
pp. 1 ◽  
Author(s):  
Wilfried Lebon ◽  
Jacques Guillot ◽  
Maria-Jesús Álvarez ◽  
José Antonio Bazaga ◽  
Marie-Laure Cortes-Dubly ◽  
...  
Keyword(s):  
Clinical History ◽  
Negative Control Group ◽  
Treated Group ◽  
Negative Control ◽  
Control Group ◽  
Morphological Identification ◽  
Thelazia Callipaeda ◽  
Milbemycin Oxime ◽  
The Past ◽  
Endemic Areas

In the past decade, canine thelaziosis due to Thelazia callipaeda has been diagnosed in an increasing number of European countries, with endemic areas being identified. A multi-center field trial was conducted in endemic areas in France and Spain to evaluate the efficacy of monthly administrations of the oral milbemycin oxime/afoxolaner combination (NexGard Spectra®) for the prevention of T. callipaeda infection in at-risk dogs. A total of 79 dogs negative for T. callipaeda and with a clinical history of eyeworm infection in the past two years completed the study. Dogs were randomly allocated either to a negative control group (42 dogs) or to the NexGard Spectra® treated group (37 dogs). All dogs were followed up for a 6-month period and assessed monthly for the presence of nematodes on the eyes and for the signs of ocular thelaziosis (e.g., conjunctivitis, keratitis, and ocular discharge). When the presence of nematodes was confirmed, the conjunctival fornix was flushed with a saline solution for parasite recovery and counting, and the dogs were treated appropriately. Recovered parasites were stored in 70% alcohol for subsequent morphological identification. During the course of the study, 57.1% (24/42) of the control dogs were diagnosed positive for Thelazia infection, which illustrates a high incidence rate of parasite infection. Conversely, no eyeworm was recovered from any of the 37 dogs that received NexGard Spectra®. All parasites sampled were confirmed to be T. callipaeda. This clinical field study demonstrated that monthly administrations of NexGard Spectra® provided 100% preventive efficacy against canine thelaziosis.

SPECIFIC BINDING OF THYROID-STIMULATING HORMONE BY HUMAN SERUM GLOBULINS

1981 ◽  
Vol 88 (3) ◽  
pp. 339-349 ◽  
Author(s):  
J. BÍRÓ
Keyword(s):  
Binding Sites ◽  
Binding Capacity ◽  
Specific Binding ◽  
Negative Control Group ◽  
Paper Electrophoresis ◽  
Negative Control ◽  
Thyroid Stimulating Hormone ◽  
Human Thyroid ◽  
Control Group ◽  
Binding Characteristics

Globulin preparations (41) from patients with Graves's disease (positive to thyroid stimulating immunoglobulins; TSI) and 12 from healthy persons (TSI-negative) were tested for their specific thyrotrophin (TSH)-binding properties. Globulins from both groups possessed binding sites for 131I-labelled TSH. The mean dissociation constant (Kd) was 6·8 pmol/l per mg globulin and the maximum specific binding (Bmax) was 3·0 pmol/mg globulin per 1 for the TSI-negative control group. Twenty-four (58·5%) globulin preparations from the TSI-positive group had similar TSH-binding characteristics with mean Kd of 7·2 pmol/l per mg globulin and Bmax of 3·6 pmol/mg globulin per 1 (A-type binding) but the remaining 17 (41·5%) bound TSH in a different fashion with Kd of 71·5 pmol/l per mg globulin and Bmax of 13·6 pmol/mg globulin per 1 (B-type binding). Both types of specific TSH binding reached the maximal level within 1 h of incubation and had an optimum pH of 7–8. There was a linear correlation between the amount of bound TSH and the globulin content of the samples. Both types of binding were reversible by the addition of an excess of TSH and gonadotrophins, ACTH, prolactin and insulin competed with TSH for the binding sites only when in relatively high concentrations. The binding sites were associated with macromolecules; they emerged with the void volume after chromatography on Sephadex G-200 and migrated with immunoglobulin G (IgG) on paper electrophoresis. The binding capacity of the globulin preparations could be decreased by preincubation with antiserum to human IgG or with human thyroid membranes.

scholarly journals Comparative Analysis of the Serological Reactivity of Individuals with Clinical History of Malaria using Two Different ELISA Tests

Diagnostics ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 168
Author(s):  
Yorleydy Ruiz Moreno ◽  
Silvia Tavares Donato ◽  
Fátima Nogueira ◽  
Marcelo Sousa Silva
Keyword(s):  
Clinical History ◽  
Negative Control ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serological Response ◽  
Serum Samples ◽  
Serological Tests ◽  
Serological Reactivity ◽  
History Of ◽  
Low Levels ◽  
Antigenic Reactivity

Early diagnosis of malaria reduces disease, prevents deaths, and contributes to decreased malaria transmission. The use of specific and sensitive antigens in the execution of serological diagnostics may have an impact on the transmission of the disease. However, many individuals cannot be easily diagnosed by serological tests due to low levels of antibodies in the serum. Using two different Enzyme-Linked Immunosorbent Assay (ELISA) tests (a commercial and an in-house ELISA), a total of 365 serum samples from individuals with a clinical history of malaria were analyzed. From the serum samples analyzed, 192 (53%) samples from the commercial ELISA and 219 (60%) samples from the in-house ELISA presented positive serological reactivity to malaria. The concordance of the samples tested (n = 365) between both ELISAs was of 67% (n = 242), and with the negative control was 100% (n = 17). We demonstrated that the in-house ELISA showed high antigenic reactivity to Plasmodium falciparum antigens when compared with the commercial ELISA. The degree of concordance of both ELISAs suggested the possibility of existence of other P. falciparum antigens present in the crude extract of P. falciparum that are important in the serological response during malaria infection.

Evaluation of Ciba Corning ACS:180 automated immunoassay system

1994 ◽  
Vol 40 (3) ◽  
pp. 407-410 ◽  
Author(s):  
J Mora-Brugués ◽  
N Gascón-Roche ◽  
J Rodríguez-Espinosa ◽  
M Cortés-Rius ◽  
F González-Sastre
Keyword(s):  
Lower Limit ◽  
Limit Of Detection ◽  
Specific Antigen ◽  
Thyroid Stimulating Hormone ◽  
Good Reliability ◽  
Technical Performance ◽  
Embryonic Antigen ◽  
And Performance ◽  
Automated Immunoassay ◽  
Stimulating Hormone

Abstract We evaluated the technical performance of the Ciba Corning ACS:180 automated immunoassay system for the following analytes: thyroid-stimulating hormone, free thyroxine, luteinizing hormone, follicle-stimulating hormone, prolactin, human chorionic gonadotropin, carcino-embryonic antigen, and prostate-specific antigen. The characteristics evaluated were: precision, carryover, linearity, lower limit of detection, analytical interferences, and comparison with other methods. Satisfactory results were obtained in the within-run and between-run precision studies. Neither sample nor reagent carryover was found for any assay. The range of linearity was acceptable. For some of the assays evaluated, the lower limit of detection was better than that claimed by the manufacturer. Correlation between ACS:180 methods and compared methods was adequate. We conclude that the ACS:180 offers good reliability, practicability, and performance capabilities.

Update of hypothyroidism and its management in Unani medicine

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Md. Anzar Alam ◽  
Mohd Aleemuddin Quamri ◽  
Ghulamuddin Sofi ◽  
Shabnam Ansari
Keyword(s):  
Thyroid Hormone ◽  
Clinical Manifestations ◽  
Signs And Symptoms ◽  
Clinical History ◽  
Developed Countries ◽  
Modern Medicine ◽  
Thyroid Stimulating Hormone ◽  
Clinical Syndrome ◽  
Hormone Deficiency ◽  
Unani Medicine

AbstractHypothyroidism is a clinical syndrome caused by thyroid hormone deficiency due to reduced production, deranged distribution, or lack of effects of thyroid hormone. The prevalence of hypothyroidism in developed countries is around 4–5%, whereas it is about 11% in India, only 2% in the UK, and 4·6% in the USA. It is more common in women than in men. Hypothyroidism has multiple etiologies and manifestations. The most common clinical manifestations are weight gain, loss of hair, cold intolerance, lethargy, constipation, dry skin, and change in voice. The signs and symptoms of hypothyroidism differ with age, gender, severity of condition, and some other factors. The diagnosis is based on clinical history, physical examination and serum level of FT3, FT4, and thyroid-stimulating hormone, imaging studies, procedures, and histological findings. The treatment of choice for hypothyroidism is levothyroxine, however; in this review article, we have discussed the epidemiology, etiology, clinical sign and symptoms, diagnosis, complications, and management of hypothyroidism in modern medicine and a comparative treatment by the Unani system of medicine (USM). In the USM, the main emphasis of the principle of treatment (Usool-e-Ilaj) is to correct the abnormal constitution (Su-e-Mizaj) and alter the six prerequisites for existence (Asbab-e-Sitta Zarooriya) to restore normal health. It is a packaged treatment, that is, different components of treatment are given as a package form which includes different drugs, dosages form, and regimens.

scholarly journals Immunofluorescence localization of glycoprotein hormones in the rat anterior pituitary gland using monoclonal antibodies and polyclonal antisera.

1982 ◽  
Vol 30 (7) ◽  
pp. 645-649 ◽  
Author(s):  
R Kofler
Keyword(s):  
Staining Technique ◽  
Thyroid Stimulating Hormone ◽  
Cell Type ◽  
Rat Pituitary ◽  
Pituitary Glands ◽  
Polyclonal Antisera ◽  
Simultaneous Identification ◽  
Mouse Antibody ◽  
Monoclonal Mouse ◽  
Stimulating Hormone

A hybridoma-derived monoclonal mouse antibody against bovine luteinizing hormone (LH) cross-reacting with rat LH and conventional polyclonal rabbit antisera against rat follicle-stimulating hormone (FSH) and thyroid-stimulating hormone (TSH) were used for the localization of the cells producing these hormones in rat pituitary glands by the immunofluorescence double staining technique. This approach enables the simultaneous identification of two different hormones on a single tissue section. It was shown that LH and FSH are produced within the same cell type, whereas TSH is synthesized by a different cell.

Clinical assessment

2019 ◽  
pp. 181-196
Author(s):  
Lindsey Cherry ◽  
Lucy Gates ◽  
Catherine Bowen
Keyword(s):  
Rheumatic Disease ◽  
Clinical Assessment ◽  
Clinical History ◽  
Future Research ◽  
Clinical Environment ◽  
Research Directions ◽  
Screening Techniques ◽  
Reference Guide ◽  
Movement Assessment ◽  
Future Research Directions

This chapter provides an overview of the importance and process for clinical assessment of the foot and ankle in rheumatology. A reference guide for obtaining a clinical history is provided, in addition to recommendations about considering psychosocial and footwear history. An overview of common screening techniques is provided, with particular reference to common serological and musculoskeletal assessment approaches. Specific examples of movement assessment are considered and the importance of clinical observation and palpation in rheumatic disease is noted in addition to the importance of understanding the complex and changing presentation of pain. Finally, insight about future research directions is provided. Overall, it is intended that readers of this chapter will find useful guidance and practical tips for use in a clinical environment.

scholarly journals Thyroid Status in Patients with Dysfunctional Uterine Bleeding in a Tertiary Care Hospital of Assam

2016 ◽  
Vol 20 (1) ◽  
pp. 11-15
Author(s):  
Jadab K Phukan ◽  
Gautom K Saharia ◽  
Rohini Goswami
Keyword(s):  
Menstrual Cycle ◽  
Tertiary Care Hospital ◽  
Tertiary Care ◽  
Abnormal Uterine Bleeding ◽  
Clinical History ◽  
Thyroid Stimulating Hormone ◽  
Uterine Bleeding ◽  
Care Hospital ◽  
Thyroid Status ◽  
Dysfunctional Uterine Bleeding

ABSTRACT Background Dysfunctional uterine bleeding (DUB) is a major form of abnormal uterine bleeding, seen in at least 10% of all new outpatient department patients. The thyroid gland is known to play an important role in maintaining a healthy menstrual cycle. Aims To assess the thyroid hormone status in apparently euthyroid patients with DUB and to correlate it with incidence of DUB. Materials and methods Fifty DUB patients were selected on the basis of clinical history, examination, and relevant investigations. Equal numbers of age-matched women with normal menstrual cycle were taken as controls. Thyroid hormones, viz., thyroid-stimulating hormone, total triiodothyronine and tetraiodothyronine, were estimated by radioimmunoassay. Statistical analysis of the data was performed by using Microsoft Excel software. Results The most common menstrual abnormality was menorrhagia (48%) followed by metrorrhagia and polymenorrhea (14% each). Hypothyroidism was more prevalent among cases (85.7%) as compared with controls (14.3%). In patients with menorrhagia, 33.3% of patients had hypothyroidism. Conclusion Hypothyroidism occurs in DUB patients commonly. There is a need for mandatory thyroid screening in all patients with menstrual irregularities to help in early detection of the cause and treatment of DUB patients to avoid surgery. How to cite this article Phukan JK, Saharia GK, Goswami R. Thyroid Status in Patients with Dysfunctional Uterine Bleeding in a Tertiary Care Hospital of Assam. Indian J Med Biochem 2016;20(1):11-15.

Sign in / Sign up

Export Citation Format

Share Document