Sensitivity Of Serological Tests Research Articles

Public Health Implications of Cysticercosis Acquired in the United States

Cysticercosis has emerged as a cause of severe neurologic disease in the United States that primarily affects immigrants from Latin America. Moreover, the relevance of cysticercosis as a public health problem has been highlighted by local transmission. We searched the biomedical literature for reports documenting cases of cysticercosis acquired in the United States. A total of 78 cases, principally neurocysticercosis, were reported from 12 states during 1954–2005. A confirmed or presumptive source of infection was identified among household members or close personal contacts of 16 (21%) case-patients. Several factors, including the severe, potentially fatal, nature of cysticercosis; its fecal–oral route of transmission; the considerable economic effect; the availability of a sensitive and specific serologic test for infection by adult Taenia solium tapeworms; and the demonstrated ability to find a probable source of infection among contacts, all provide a compelling rationale for implementation of public health control efforts.

Clinical, histological and immunpathological findings in 32 patients with dermatitis herpetiformis Duhring

Dermatitis herpetiformis is a chronic severely pruritic dermatosis. It is a cutaneous manifestation of celiac disease. The aim of our study was to collect clinical, histological and immunopathological data on patients who were treated in the University Departments of Dermatology in Würzburg and Lübeck from 1996 to 2008. We retrospectively analyzed 32 patients. Only patients with positive findings on direct immunofluorescence microscopy were included in this study. All patients demonstrated skin lesions in the predilection areas of knees, elbows, gluteal region and scalp. The male to female ratio was 1.5 : 1 and the average age was 43 years. The interval between the first symptoms and diagnosis ranged from 6 weeks to 20 years. Direct immunofluorescence microscopy showed that granular IgA deposits were more often found continuously along the dermal-epidermal junction rather than focally in the tips of the dermal papillae. Results of small intestinal biopsies were available from 29 patients and confirmed the presence of celiac disease in all cases. None of the patients reported gastrointestinal symptoms. IgA antibodies against tissue transglutaminase and epidermal transglutaminase were found in 88% and 94% of patient sera, respectively. The detection of IgA autoantibodies against epidermal transglutaminase is the most sensitive serological test in the diagnosis of dermatitis herpetiformis. Our observations confirm that patients with dermatitis herpetiformis usually do not demonstrate apparent gastrointestinal symptoms.

Comparative evaluation of immunofluorescent antibody and new immunoblot tests for the specific detection of antibodies against Besnoitia besnoiti tachyzoites and bradyzoites in bovine sera

Besnoitia besnoiti, an apicomplexan parasite causes economically important disease in cattle in many countries of Africa and Asia is re-emerging in Europe. Serological identification of infected cattle is important because introduction of these animals into naive herds seems to play a major role in the transmission of the parasite. We report new, simplified immunoblot-based serological tests for the detection of B. besnoiti-specific antibodies. Antigens were used under non-reducing conditions in the immunoblots, because reduction of the antigen with β-mercaptoethanol diminished the antigenicity in both, tachyzoites and bradyzoites. Ten B. besnoiti tachyzoite and ten bradyzoite antigens of 15–45 kDa molecular weight were recognized by B. besnoiti infected cattle, but not or only weakly detected by cattle infected with related protozoan parasites, Neospora caninum, Toxoplasma gondii, Sarcocystis cruzi, Sarcocystis hominis, or Sarcocystis hirsuta. The sensitivity and specificity of B. besnoiti immunoblots were determined with sera from 62 German cattle with clinically confirmed besnoitiosis and 404 sera from unexposed German cattle including 214 sera from animals with a N. caninum-specific antibody response. Using a new scoring system, the highest specificity (100%) and sensitivity (90%) of the immunoblots were observed when reactivity to at least four of the ten selected tachyzoite or bradyzoite antigens was considered as positive. When a cut-off based on this scoring system was applied to both the tachyzoite- and the bradyzoite-based immunoblots, there was an almost perfect agreement with the indirect fluorescent antibody test with a titre of 200 as the positive cut-off. We identified and partially characterized 10 tachyzoite and 10 bradyzoite B. besnoiti antigens which may help to develop new specific and sensitive serological tests based on individual antigens and in the identification of possible vaccine candidates.

Emerging infections in Asia and its possible global effects.

Emerging infections in Asia and its possible global effects.

6001 International randomised phase III study of capecitabine (Cap), bevacizumab (Bev) and mitomycin C (MMC) in first line treatment of metastatic colorectal cancer (mCRC): final results of the AGITG MAX trial

Background/Aims: Antineutrophil cytoplasmic antibodies are reported in patients with chronic liver disease, but controversy exists about their prevalence and specificity. We aimed to find the prevalence and specificity of antineutrophil cytoplasmic antibodies in chronic liver diseases by determination of antineutrophil cytoplasmic antibody titre and IgG subclass.Methods: One hundred and eight-four sera were studied: 63 primary sclerosing cholangitis, 28 autoimmune hepatitis, 34 primary biliary cirrhosis, 12 alcoholic liver disease, five large duct obstruction, four haemochromatosis, one chronic cholestatic syndrome, one cryptogenic cirrhosis and 36 normal individuals. Antineutrophil cytoplasmic antibodies were detected on alcohol-fixed neutrophils using an alkaline phosphates technique. The IgG subclass of antineutrophil cytoplasmic antibodies was determined using monoclonal antibodies: HP 6001 for IgG1, HP 6002 for IgG2, HP 6050 for IgG3 and SK 44 for IgG4 (Sigma Immunochemicals).Results: Antineutrophil cytoplasmic antibodies were detected in 65% of primary sclerosing cholangitis patients at a serum dilution of 1:5, dropping to 49% at 1:50. For autoimmune hepatitis, antineutrophil cytoplasmic antibodies were detected in 49% at 1:5, dropping to 11% at 1:50. Only 6% of primary biliary cirrhosis patients were antineutrophil cytoplasmic antibody-positive at 1:5, dropping to 3% at 1:50. All other controls were antineutrophil cytoplasmic antibody negative at 1:5. The presence of antineutrophil cytoplasmic antibodies in primary sclerosing cholangitis correlated with involvement of the intra- and extrahepatic biliary tree (p=0.016, Fisher's exact test), but no other clinical parameters. Determination of the IgG subclass of antineutrophil cytoplasmic antibody in 33 primary sclerosing cholangitis and 11 autoimmune hepatitis patients revealed a predominance of IgG1 in both groups (94% and 82% of all IgG antineutrophil cytoplasmic antibodies, respectively), with a similar distribution of IgG2, IgG3 and IgG4 antineutrophil cytoplasmic antibodies between the groups.Conclusions: Antineutrophil cytoplasmic antibodies are specific to the autoimmune liver diseases, particularly primary sclerosing cholangitis and autoimmune hepatitis. Titres are highest in primary sclerosing cholangitis, with a diagnostic sensitivity of 49% and specificity of 89% at 1:50, making it a useful serological marker for this disease. The lack of correlation with any marker of activity and the association of antineutrophil cytoplasmic antibody with extent of biliary tract involvement suggest that antineutrophil cytoplasmic antibodies arises as a result of the disease or related process rather than being a cause of it. The detection of antineutrophil cytoplasmic antibodies in autoimmune hepatitis, together with a similar IgG subclass distribution of primary sclerosing cholangitis and autoimmune hepatitis antineutrophil cytoplasmic antibodies, may reflect similar mechanisms of immune regulation and a possible overlap syndrome. Future identification of the antigens against which this antineutrophil cytoplasmic antibody are directed should help to clarify this point, as well as allowing the development of a more sensitive and specific serological test for diagnostic purposes.

High prevalence of co-infections with bovine herpesvirus 1 and 5 found in cattle in southern Brazil

Based on small scale studies or on little sensitive serological tests, bovines in the south of the state of Rio Grande do Sul, Brazil, are known to be infected with either bovine herpesvirus 1 (BoHV-1) or 5 (BoHV-5). However, whether the prevalence of each of these viruses is high or low is currently still unknown. In order to determine the extent of BoHV (-1 and/or -5) infections in bovines in this region of Brazil, 200 bovines were studied for the presence of BoHV DNA. To this end, first a quantitative PCR was developed that amplified BoHV-1 DNA as well as BoHV-5 DNA. Using this PCR the number of BoHV genomes normally present in latently infected ganglia of naturally infected bovines was estimated. The new PCR was sensitive enough to detect most BoHV DNA in infected ganglia. The results of this first PCR showed that at least 87% of the bovines in the south of Rio Grande do Sul were (latently) infected with either BoHV-1 or BoHV-5. To determine the prevalence of BoHV-1 and BoHV-5 separately, two type-specific PCRs – one for each virus – were developed that used the products of the first PCR as a template. The results of these type-specific PCRs showed that 82.8% of the BoHV positive population was (latently) infected with BoHV-1, 93.1% with BoHV-5 and 75.9% with both BoHV-1 and BoHV-5. This is the first time that such a high frequency of co-infection of BoHV-1 and BoHV-5 in bovines has been demonstrated.

PCR diagnosis of visceral leishmaniasis in an endemic region, Mymensingh district, Bangladesh

Detection of Leishmania parasites in a clinical sample is necessary to confirm a suspected case of leishmaniasis. We compared the sensitivity of internal transcribed spacer 1-PCR (ITS 1-PCR) assay for parasite diagnosis with that of microscopic detection in clinical samples from kala-azar (KA) or post-kala-azar dermal leishmaniasis (PKDL) suspects in Mymensingh. Of 39 specimens collected from 35 KA and four PKDL suspects, 26 were positive by microscopic examination of smears from bone marrow and skin exudates; 38 specimens spotted on filter paper and 27 of the 28 Giemsa-stained slides tested by PCR proved positive by ITS1-PCR.

Susceptometric avaliation of chelation with deferoxamine

Abstract Transfusion safety is a major concern all over the world with newtechnologies being developed to increase the protection of patients.Developed countries and some Brazilian private blood banks havealready implemented tests to detect HIV and HCV nucleic acid ma-terial (NAT). Despite the increase in transfusion safety promoted bythese tests, financers and administrators are resistant to pay for itswidespread implementation. We report here on the detection of awindow period for HIV identified by the NAT test: A donor candidateshowed up at the blood bank in August 2007 and after a clinicalinterview and hematological screening he was considered suitablefor donation and did not choose self-exclusion. All serologic testswere negative except NAT for HIV. Twelve days after donating, thedonor returned to draw another blood sample, which was positivefor NAT for HIV and combined ELISA Ag/Ab. On this occasion, hereported that he was being treated for pneumonia and had hadhomosexual relationships within the 4 weeks preceding blooddonation. One week after this second sample, a third one wascollected, which resulted in being positive for NAT, ELISA Ag/Aband ELISA HIV ½. This report illustrates the importance ofperforming the most sensitive serologic screening tests possible inblood donors, and reiterates the responsibility of physicians, hospitalsand financers. It is important to emphasize the obligation of usingevery available resource in order to increase transfusion safety asneglect is an ethical infraction with legal responsibilities. Rev. bras.hematol. hemoter. 2008; 30(4):330-331.

PRISM hepatitis B surface antigen detection of hepatits B virus minipool nucleic acid testing yield samples

Hepatitis B virus (HBV) residual risk has been estimated at 1:63,000-1:205,000 and introduction of more sensitive serological tests and nucleic acid testing (NAT) would reduce that risk. Sensitivity of the recently licensed Abbott PRISM hepatitis B surface antigen (HBsAg) CLIA and minipool (MP) HBV NAT has been described as comparable and thus the need for HBV NAT has not been compelling. In this study, eight samples identified as yield samples with MP HBV NAT were tested using the PRISM test. Seven samples were identified using the Roche COBAS AmpliScreen HBV test and one additional sample was obtained from the clinical trial for the Roche cobas TaqScreen MPX test. Each of these samples was reactive by MP HBV NAT and nonreactive for HBsAg using one of three licensed enzyme immunoassay (EIA) tests. After licensure of the PRISM HBsAg, aliquots were tested with this assay, and DNA quantitation and genotyping were repeated where sample volume permitted. Three samples (2000, 2300, and 61,000 copies/mL) produced reactive results with PRISM. Four samples with viral loads less than 300 copies per mL produced nonreactive results. One sample, originally quantitated at 37,000 copies per mL (but 3850 copies/mL in repeat testing) was also nonreactive by PRISM. Genotyping of this sample indicated a type C genotype with no mutations. Adding serological sensitivity of PRISM CLIA reduced the NAT yield from the original 1: 385,555 to 1:610,488. However, MP HBV NAT still provides additional sensitivity over CLIA, even for a donation with a viral load of almost 4000 copies per mL.

Diagnostic and therapeutic approach to persistent or recurrent fevers of unknown origin in adult stem cell transplantation and haematological malignancy

Persistent or recurrent fevers of unknown origin (PFUO) in neutropenic patients on broad-spectrum antibiotics have traditionally been treated with empirical antifungal therapy (EAFT). The lack of survival benefit seen with the use of amphotericin B deoxycholate (AmB-D) as EAFT has been attributed to its toxicities. More recently, newer, less toxic and more expensive antifungal agents such as the lipid formulations of AmB, the newer azoles (fluconazole, itraconazole and voriconazole) and caspofungin have been analysed in a number of EAFT trials. Compared with AmB-D the newer agents have superior safety but are of equivalent efficacy. This lack of survival advantage is related to the fact that the trigger for commencement of EAFT is late and non-specific. Thus, alternative approaches are required. New sensitive serological and molecular tests for the detection of Aspergillus antigens and genomic DNA have been developed and evaluated in accuracy studies. These tests have been incorporated into management strategies (i.e. pre-emptive strategies) to direct antifungal therapy. The pre-emptive approach has been shown to be safe and feasible but its impact on clinically important patient outcomes such as survival is less clear. Other advances include the introduction of effective, non-toxic mould-active antifungal prophylaxis and patient risk-group stratification. In this paper we provide new evidence-based algorithms for the diagnosis and treatment of PFUO in adult patients undergoing stem cell transplantation and chemotherapy for haematological malignancy which incorporate these newer diagnostic tests and are directed by the risk category of the patient and type of antifungal prophylaxis the patient is receiving.

Human immunodeficiency virus: a global problem with ongoing implications for transfusion medicine

Human immunodeficiency virus (HIV) epidemic continues to expand globally, despite 25 years of unprecedented investment in basic and applied research and major advances in behavioural interventions that reduce transmission and development of therapeutic regimens to treat infected persons. Although transfusion-transmitted HIV is now very rare in developed countries where low-risk donor selection and sensitive serological and nucleic acid amplification technology (NAT) testing are routine, transfusion transmission continues at disturbing rates in some regions of Africa, South-East Asia and Eastern Europe where donor selection is less effective and where NAT screening is not affordable and effective systems to control release of positive units are not always in place. This review will summarize the scope of the global HIV epidemic. Key accomplishments in reducing HIV transmission, particularly by transfusions, and in treating infected persons will be discussed. We will then consider areas where scientific progress has been limited, such as continued frustration in efforts to develop effective prophylactic vaccines and microbicides, the inability to eradicate established infections with antiretroviral drugs or immunotherapeutic approaches, and the problem with development and spread of increasingly diverse viral variants and drug-resistant HIV. Finally, the review will highlight several recent areas where research originally designed to address questions in the context of understanding acute infection for preventing transfusion-transmitted HIV has provided insights into HIV pathogenesis and contributed to improved diagnosis and epidemiologic monitoring of HIV infection on a much broader scale.

Diagnostic de la maladie cœliaque en 2008

Since the 1990's, the widespread use of very sensitive and specific serological tests has completely changed the conditions of the diagnosis of celiac disease (CD). The active form of the disease is now only the tip of the iceberg representing it. Currently, CD is evoked either in front of mild digestive symptoms at the usual age or in the course of screening in siblings of an index case or in patients at risk (insulin dependent diabetes for example) at a later age using IgA anti-endomysium or anti-tissue transglutaminase antibodies, the sensitivities and specificities of which exceed 90%. In some cases, HLA typing is helpful in allowing to exclude a patient who is neither DQ2 nor DQ8. The intestinal biopsy remains the “gold standard” of the diagnosis showing villous atrophy; the latter, however, is less and less often severe as the disease is milder and milder. The diagnosis of CD then rests on the confrontation of the clinical, biological and histological data. Once CD has been diagnosed, it can be classified either as active or silent (positive serology with isolated villous atrophy), or latent (positive serology with a normal mucosa) and the appropriate therapeutic decision can be taken.

Celiac disease

Celiac disease is an autoimmune disorder caused by the continued ingestion of gluten, a protein found in wheat, barley and rye, by predisposed individuals. With the development of highly sensitive serologic tests, this has become an increasingly recognized disease with prevalence as high as 1% in certain patient populations, such as Caucasian females. Almost all celiac patients carry the human leukocyte antigen DQ2/DQ8 gene. Much has recently been discovered about the role of the innate immune system in exposing genetically vulnerable patients to the pathogenic gliadin fraction of gluten. The "classical" presentation of chronic diarrhea and malabsorption is now a rarity. Due to earlier detection and increased awareness, celiac disease now presents with a myriad of "atypical" signs and symptoms such as iron-deficiency anemia and osteoporosis. Associated conditions include T-cell lymphoma, dermatitis herpetiformis, autoimmune thyroiditis and type 1 diabetes. Diagnosis requires serologic confirmation with either antiendomysial or antitransglutaminase antibodies as well as histologic confirmation from endoscopic small bowel biopsy. The only effective treatment necessitates a lifelong, continual adherence to a gluten-free diet.

Implications of Using a Highly Sensitive Serological Test as a Screening Modality for the Diagnosis of Syphilis

Implications of Using a Highly Sensitive Serological Test as a Screening Modality for the Diagnosis of Syphilis

Multiplex Fluorescent Immunoassay for the simultaneous detection of serum antibodies to multiple rodent pathogens

Multiplex Fluorescent Immunoassay (MFI) is a sensitive and specific serologic test that allows simultaneous detection of antibodies to multiple viral and bacterial agents in a single reaction well. MFI is a high-throughput assay that offers several advantages over other prevalent assays, and some research animal diagnostic laboratories have adopted it as their primary technique. The authors present a detailed review of MFI and its application to laboratory animal diagnostics.

Selected Summary

Selected Summary

Celiac disease in the developing countries: A new and challenging public health problem

In the past, celiac disease was believed to be a chronic enteropathy, almost exclusively affecting people of European origin. The availability of new, simple, very sensitive and specific serological tests (anti-gliadin, anti-endomysium and anti-transglutaminase antibody assays) have shown that celiac disease is common not only in Europe and in people of European ancestry but also in the developing countries where the major staple diet is wheat (Southern Asia, the Middle East, North West and East Africa, South America), both in the general population and in the groups at risk. Gluten intolerance thus appears to be a widespread public health problem and an increased level of awareness and clinical suspicion are needed in the New World where physicians must learn to recognize the variable clinical presentations (classical, atypical and silent forms) of celiac disease. In the developing countries, both serological screening in the general population and serological testing in groups at risk are necessary for an early identification of celiac patients. The gluten-free diet poses a challenging public health problem in the developing countries, especially since commercial gluten-free products are not available.

Clinical significance of antinucleosome antibodies in patients with “early” systemic lupus erythematosus

Система комплексной поддержки и сопровождения научного журнала Elpub позволяет запустить двуязычный сайт журнала со встроенной системой электронной редакции в соответствии с лучшими издательскими практиками, а так же предусматривает техническую и методическую поддержку со стороны специалистов НЭИКОН.

The economic impact of visceral leishmaniasis on households in Bangladesh

To explore current patterns of diagnosis and treatment, quantify household economic impact and identify household strategies to cover the costs of visceral leishmaniasis (VL) care in rural Bangladesh. Structured interviews with 113 VL patients from 87 households documenting all provider visits and expenditures for health care for VL, and the ways in which the expenditures were covered. Patients paid a median of 7 visits to six different providers before beginning VL treatment. All visited the subdistrict government hospital at least once. While health care, including antileishmanial drug therapy, is officially available free of charge at government facilities, 79% of patients reported making informal payments for provider access, diagnostics and drug administration; only 14% of patients received their full drug course from this source. For the 58% of patients who purchased the full treatment course, drug cost constituted 34% of direct expenditure. Median direct expenditure for one VL patient was US$87 and median income lost was $40; median total expenditure was 1.2 times annual per capita income of our study population. Households employed multiple coping strategies to cover expenditures, most commonly sale or rental of assets (62%) and taking out loans (64%). Visceral leishmaniasis treatment causes a major economic burden in affected families. Control strategies for VL should facilitate timely, affordable diagnosis and treatment of patients to decrease the infection reservoir and to alleviate the economic burden of VL on households.

What's the case for case-finding in primary care for coeliac disease?

The advent of highly sensitive and specific serologic tests, namely human tissue transglutaminase (tTG) and endomysial (EMA) antibodies, have revealed that coeliac disease is underdiagnosed in Western Europe and North America and its prevalence, in the general, population of approximately 1% is much higher than was previously thought [1]. Serologic testing also reveals that the diagnosis is now increasingly being made in adult life with the mean age at presentation currently being 45 years, with about 20% of diagnoses occurring in patients who are older than 60 years [2]. Furthermore, presenting clinical symptoms have changed dramatically over the last 50 years. Adult patients are more likely to present with extra-intestinal man-