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Background: The acronym 'TORCH' refers to well-recognised causes of perinatal infections: toxoplasmosis, rubella, cytomegalovirus (CMV) and herpes simplex virus (HSV). A TORCH serology panel is often used to test for maternal primary infection following detection of ultrasound abnormalities in pregnancy., Aim: This review aims to estimate the diagnostic yield of maternal TORCH serology in pregnancy following fetal ultrasound abnormalities., Materials and Methods: Primary studies published since 2000 that assessed maternal TORCH serology for suspected fetal infection and included information on indications for testing, definition of positive TORCH serology results, and perinatal outcomes were included., Results: Eight studies with a total of 2538 pregnancies were included. The main indications for testing were polyhydramnios, fetal growth restriction and hyperechogenic bowel. There were 26 confirmed cases of congenital CMV, of which 15 had multiple ultrasound abnormalities. There were no cases of congenital toxoplasmosis, rubella or HSV confirmed in any of the eight studies., Conclusions: The clinical utility of TORCH serology for non-specific ultrasound abnormalities such as isolated fetal growth restriction or isolated polyhydramnios is low. It is time to retire the TORCH acronym and the reflex ordering of 'TORCH' panels, as their continued use obscures, rather than illuminates, appropriate investigation for fetal ultrasound abnormalities., (© 2021 John Wiley & Sons Ltd.)

Background: Breast cancer (BC) is a major health issue threatening women's life. No reliable epidemiological data on BC diagnosed by oncologists/senologists are available in Algeria., Methods: The BreCaReAl study, a non-interventional prospective cohort study, included adult women with confirmed BC in Algeria. Disease incidence, patients and disease characteristics, treatment patterns, and mortality rate were recorded up to 12 months of follow-up., Results: Overall, 1,437 patients were analysed: median age was 48 [41;57] years and 337 (23.5%) women had a family history of BC. BC incidence was 22.3 (95% CI: 21.5; 23.2) cases per 100,000 inhabitants over 8 months. Delayed diagnosis was reported in 400 (29.2%) patients. First line of treatments were mainly chemotherapy and surgery. Twenty-eight serious adverse events were reported including 10 (37.0%) events which led to death. Mortality rate reached 3.2% at 12 months CONCLUSION: A delayed diagnosis highlights the importance of implementing more effective screening strategies., (Copyright © 2020. Published by Elsevier Ltd.)

Since the discovery of Helicobacter pylori (H. pylori) in 1983, numerous detection methods for the presence of the bacterium have been developed. Each one of them has been associated with advantages and disadvantages. Noninvasive tests such as serology, (13)C urea breath test (UBT) and stool antigen tests are usually preferred by the clinicians. Serology has its own limitation especially in endemic areas while (13)C UBT is technically very demanding. The stool antigen detection method, although specific, is usually associated with poor sensitivity. The (13)C UBT is believed to be specific, but with present revelation of the fact that stomach is colonized by many other urease producing bacteria makes it questionable. Histology, culture, rapid urease test and polymerase chain reaction (PCR) are the tests which are carried out on antral biopsies collected by invasive means. Histology has been proposed to be very sensitive and specific but the question is how by simply looking the morphology of the bacteria in the microscope, one can claim that the curved bacterium is exclusively H. pylori. Rapid urease test (RUT), the doctor's test, is also challenged because the presence of other urease producing bacteria in the stomach cannot be denied. Moreover, RUT has been reported with poor sensitivity specially, when density of the bacterium is low. Isolation of H. pylori is essential to investigate its growth requirements, antibiotic susceptibility testing, studying virulence factor to develop vaccine and many more explorations. It has also got several disadvantages i.e., special condition for transporting, media, incubation and few days waiting for the colonies to appear, apart from the speed essentially needed to process the specimens. Till date, majority of the microbiological laboratories in the world are not equipped and trained to isolate such fastidious bacterium. The option left is PCR methods to detect H. pylori's DNA in gastric mucosa, gastric juice, saliva, dental plaques and environmental specimens. There are speculations for false positivity due to detection of non-pylori Helicobacters due to genetic sharing; and false negativity due to low bacterial counts and presence of PCR inhibitors. However, specimen collection, transportation and processing do not require speed and special conditions. PCR based diagnosis may be considered as gold standard by designing primers extremely specific to H. pylori and targeting at least more than one conserved genes. Similarly specificity of PCR may be improved by use of internal Primers. Further, nested PCR will take care of false negatives by countering the effect of PCR inhibitors and low bacterial counts. Therefore, nested PCR based methods if performed properly, may be proposed as gold standard test.

Suitably controlled serosurveillance surveys are essential for evaluating human papillomavirus (HPV) immunization programs. A panel of plasma samples from 18-year-old females was assembled, the majority of the samples being from recipients of the bivalent HPV vaccine. Antibody specificities were evaluated by three independent laboratories, and 3 pools that displayed no antibodies to any HPV type tested or intermediate or high levels of antibody to HPV16, HPV18, HPV31, and HPV45 were created. These pools will be useful as control reagents for HPV serology.

The External Quality Control Program of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) includes controls for bacteriology, serology, mycology, parasitology, mycobacteria, virology and molecular microbiology. In this article, the most important conclusions and lessons from the 2009 controls are presented. As a whole, the results obtained in 2009 confirm the excellent skill and good technical standards found in previous editions. However, erroneous results can be obtained in any laboratory and in clinically relevant determinations. The results of this program highlight the need to implement both internal and external controls in order to ensure maximal quality of microbiological tests., (Copyright © 2011 Elsevier España S.L. All rights reserved.)

The External Quality Control Program of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) includes controls for bacteriology, serology, mycology, parasitology, mycobacteria, virology and molecular microbiology. This article presents the most important conclusions and lessons drawn from the 2007 controls. As a whole, the results obtained in 2007 confirm the excellent skill and good technical standards found in previous years. However, erroneous results can be obtained in any laboratory and in clinically relevant determinations. A few deviations were observed in some controls, calling for critical reflection. Once again, the results of this program highlighted the need to complement internal with external controls, such as those offered by the SEIMC program.

Background & Aims: Screens for serologic markers of hepatitis B virus (HBV) are used to prevent its transmission through transplantation. However, exclusion of noninfectious seropositive donors exacerbates graft shortages, and a residual risk of transmission by seronegative donors also exists. This study assessed the risk of HBV associated with different HBV serologic profiles in organ, tissue, and cell transplants, as well as the risk of HBV transmission from seronegative donors., Methods: A total of 11,155 consecutive organ, tissue, and cell donors were screened for HBV serologic markers. HBV DNA was screened for in 626 donors with at least one HBV serologic marker and 1433 multiple organ donors who were HBV seronegative or had anti-hepatitis B surface antigens (HBs) antibodies alone., Results: HBV DNA was detected in most HBs-antigen-positive donors, but HBV-DNA levels were considerably lower than in patients with chronic hepatitis B. HBV DNA also was found in organ and cornea donors without HBs antigen. The prevalence of HBV DNA in organ donors with no HBV serologic markers or isolated anti-HBs antibodies was 0.07% (95% confidence interval, 0.01%-0.40%). One HBV-DNA-positive organ donor with isolated anti-HBs antibodies had amino acid substitutions in the hepatitis B surface antigen sequence., Conclusions: The analytic sensitivity of commercial hepatitis B surface antigen assays and their ability to detect HBsAg mutants should be improved. The utility and cost-efficacy ratio of systematic HBV-DNA testing should be assessed with the goal of excluding HBV-DNA-positive donations not identified through serologic testing while retaining donations that carry no risk of HBV transmission.

Minimal standards for novel species of the class Mollicutes (trivial term, mollicutes), last published in 1995, require revision. The International Committee on Systematics of Prokaryotes Subcommittee on the Taxonomy of Mollicutes proposes herein revised standards that reflect recent advances in molecular systematics and the species concept for prokaryotes. The mandatory requirements are: (i) deposition of the type strain into two recognized culture collections, preferably located in different countries; (ii) deposition of the 16S rRNA gene sequence into a public database, and a phylogenetic analysis of the relationships among the 16S rRNA gene sequences of the novel species and its neighbours; (iii) deposition of antiserum against the type strain into a recognized collection; (iv) demonstration, by using the combination of 16S rRNA gene sequence analyses, serological analyses and supplementary phenotypic data, that the type strain differs significantly from all previously named species; and (v) assignment to an order, a family and a genus in the class, with an appropriate specific epithet. The 16S rRNA gene sequence provides the primary basis for assignment to hierarchical rank, and may also constitute evidence of species novelty, but serological and supplementary phenotypic data must be presented to substantiate this. Serological methods have been documented to be congruent with DNA-DNA hybridization data and with 16S rRNA gene placements. The novel species must be tested serologically to the greatest extent that the investigators deem feasible against all neighbouring species whose 16S rRNA gene sequences show >0.94 similarity. The investigator is responsible for justifying which characters are most meaningful for assignment to the part of the mollicute phylogenetic tree in which a novel species is located, and for providing the means by which novel species can be identified by other investigators. The publication of the description should appear in a journal having wide circulation. If the journal is not the International Journal of Systematic and Evolutionary Microbiology, copies of the publication must be submitted to that journal so that the name may be considered for inclusion in a Validation List as required by the International Code of Bacteriological Nomenclature (the Bacteriological Code). Updated informal descriptions of the class Mollicutes and some of its constituent higher taxa are available as supplementary material in IJSEM Online.

We consider the impact of test properties on the required sample size for the Bayesian design problem for comparing two proportions with error-prone data. Specifically, we examine four cases: a single diagnostic test and two independent diagnostic tests, both when the test properties are identical across populations and when they differ. Interval-based and moment-based sample-size determination criteria are contrasted using Monte Carlo simulation methods. We consider an application in which Strongyloides infections are compared in two populations., (Copyright (c) 2005 John Wiley & Sons, Ltd.)

The aim of the European Sero-Epidemiology Network 2 (ESEN2) is to compare standardised serological results of vaccine preventable diseases across Europe. In order to adjust for laboratory and assay differences, the participant laboratories tested a standardisation panel for each disease and the results were plotted against those of a reference centre in order to obtain standardisation equations. We describe an algorithm for obtaining these equations which took into account outliers, censored data and model selection, and needed to be robust due to the variety of assays and diseases under investigation. If the standardisation equations explained sufficient variability, these were used to convert each country's main serum bank results to a common unitage, thereby allowing international comparisons to be made.

One hundred and forty five Mabs against RH antigens were tested. In this paper, we chose to detail reactivity of MoAbs directed against variant RBCs of the CNRGS collection for which we studied the molecular background. Because we developed procedures to identify variants of the RhD, RhC, RhE and Rhe antigens, we were especially interested in finding new monoclonal antibodies that could help us to characterize more accurately these variants. Therefore, we drew parallels between our procedures and results obtained with the 2001 workshop antibodies.

Objective: To describe the trends in the profile of blood donors from 1995 through 2001 at a large blood center in the city of São Paulo, Brazil, particularly following the initiation in 1998 of marketing strategies aimed at substituting replacement donors with altruistic repeat donors., Methods: Using an information system that had been established at the Pro-Blood Foundation/Blood Center of São Paulo (Fundação Pró-Sangue/Hemocentro de São Paulo) in 1994, we collected information on sex, age, and type of donation for the years 1995-2001. We classified blood donors as either replacement blood donors (if they stated that the reason for donating was that they had a friend or relative in the hospital) or as altruistic donors. First-time blood donors were those who had not donated in our institution since the establishment of the information system., Results: The percentage of repeat altruistic blood donors increased over time as first-time replacement donors declined for both genders. The proportion of altruistic donors climbed from 20% of all blood donors in 1995 to 57% in 2001. In 2001, first-time blood donors represented only 52% of all donors, as contrasted to 88% in 1995. Female donors increased from 20% to 37% of the donors over the period studied., Conclusions: Our data provide evidence that the São Paulo population has responded well to the marketing strategies that have been introduced in our institution. We believe that similar promotional efforts elsewhere in Brazil would produce comparable, positive results.

Objective: To analyze the serological results found in Colombian blood banks that participate in the external quality program (EQP) of that country's National Institute of Health, in order to improve the quality of the screening of blood for the main serological markers of transfusion-transmitted infectious diseases., Methods: Each blood bank received a panel of six sera with different reactivity and positivity to hepatitis B surface antigen (HBsAg), as well as to antibodies to HIV 1-2, Trypanosoma cruzi (the causative agent of Chagas' disease), Treponema pallidum (the causative agent of syphilis), hepatitis B core (HBc) antigen, hepatitis C virus (HCV), and human T-lymphotropic virus (HTLV). The screening techniques used were enzyme-linked immunosorbent assay (ELISA), microparticle enzyme immunoassay (MEIA), and hemagglutination. With the panel sera, the participating blood banks were asked to apply the same tests that they use on a daily basis to screen blood units and to send their results to the National Blood Banks Unit of the Colombian National Institute of Health., Results: Of the 46 blood banks participating in the EQP, 43 of them (93%) returned their results within the requested timeframe. The ELISA test was the one that was used most often (83.0%). There were a total of 49 (5%) false positive results and 12 (3%) false negative results. Of those 12 false negative results, 6 of them corresponded to the detection of syphilis, 2 to Chagas' disease, 2 to anti-HBc antibodies, 1 to anti-HCV antibodies, and 1 to HBsAg. Eighty percent of the discordant results came from 23 blood banks that each collected fewer than 6 000 units of blood per year, and 15% came from 5 blood banks that collected 6 000 to 12 000 units per year. One of the blood banks that collected more than 12 000 units annually had three false positive results, and none of those larger blood banks had any false positive results., Conclusions: The percentage of false negative results (3%) found during the EQP can be considered high, since tests that are negative during blood screening are not repeated, and the decision to declare a unit of blood suitable for transfusion is based on that single result. There is a need to thoroughly review the procedures for screening blood in Colombia, particularly at the centers that performed poorly in this EQP exercise.

Objective: To outline principles, advantages and limitations of the currently available laboratory methods for diagnosis and detection of drug resistance of Mycobacterium tuberculosis complex., Data Source: Published series of peer reviewed journals and manuals written on laboratory methods that are currently used for diagnosis and detection of drug resistance of Mycobacterium tuberculosis complex were reviewed using the index medicus, pubmed and medline search. Conventional bacteriological microscopy and culture, BACTEC, and molecular-based techniques were included. Basic principles, advantages and limitations of the cited techniques have been highlighted., Conclusion: Conventional bacteriological microscopy and culture are usually used for diagnosis of tuberculosis (TB) particularly in developing countries. However, their limited sensitivity, specificity and delayed results make this provision inadequate. Despite the development of quicker and more sensitive novel diagnostic techniques, their complexity and high cost has limited their use in many poor-resource countries. Due to the rapidly growing TB problem in these countries, there is urgent need to assess promising alternative methodologies in settings with high disease prevalence.

A new standard meningococcal reference serum designated CDC1992 was prepared to replace meningococcal reference sera ECG and PB-2, which are not available in sufficient quantities for continued use as primary reference sera. CDC1992 was prepared from 14 healthy adult volunteers who underwent plasmapheresis 4 to 12 weeks postvaccination with a single dose of a Neisseria meningitidis quadrivalent polysaccharide vaccine. Total and/or class-specific meningococcal serogroup A and C anticapsular antibody concentrations (in micrograms per milliliter) were assigned to CDC1992 by using homologous and heterologous enzyme-linked immunosorbent assay (ELISA) formats. The reference serum ECG was used as a reference standard to assign total anticapsular antibody concentrations to CDC1992 by a homologous ELISA format. A heterologous ELISA format, with the Haemophilus influenzae type b standard reference serum FDA 1983, was used to assign total and class-specific antibody concentrations to CDC1992. Alkaline phosphatase-labeled mouse anti-human monoclonal antibody conjugates were used as secondary antibodies in both ELISA formats. The total, immunoglobulin G (IgG), IgA, and IgM antibody concentrations, assigned to CDC1992 for serogroup A were 135.8, 91.8, 20.1, and 23.9 micrograms/ml, respectively, and those for serogroup C were 32.0, 24.1, 5.9, and 2.0 micrograms/ml, respectively. Meningococcal serogroup A and C antibody concentrations were in good agreement when homologous and heterologous ELISA format results were compared. Total and class-specific serogroup A and C antibody concentrations were determined in six adult quality control serum samples from the Centers for Disease Control and Prevention by using the homologous ELISA and our assigned antibody concentrations for CDC1992. Antibody concentrations in reference sera ECG and PB-2 were measured in order to provide a historical link to previous studies. The general acceptance of CDC1992 as the standard reference serum and the assigned antibody concentrations will allow investigators to compare antibody levels in serum to those in a single reference preparation.

A programme for external quality control in blood group serology has been run in Norway since 1983 by the National Institute of Public Health. Uncomplicated AB0 and Rh(D) grouping, including Du typing, has been performed satisfactorily. Rh(D) grouping of presensitized, Rh (D) negative cells is still a problem, but one which has been reduced significantly. Both indirect and direct antiglobulin reactions have given about 15% false negative results, mainly with weak antibodies and weakly sensitized cells. Poor training of technicians in reading weak agglutination reactions may be an important source of error. The importance of post-graduate training of blood bank staff is emphasized.

Isohemagglutinins alpha and beta were neutralized by soluble synthetic group A and B substances in group ++anti-rhesus sera. The investigations conducted have shown that water-soluble polymers A and B are efficient agents for the preparation of universal ++anti-rhesus sera. The neutralizing properties of synthetic and natural group A and B substances were comparatively studied.

A review of the reactive serological tests for syphilis was carried out. An overall seroreactivity of 5.1% was obtained over the 10-year period reviewed. A subtle but steady rise in the incidence of syphilitic infections was noted, from 7 to 10 new cases per 1000 population between 1970 and 1975. The predictive characteristics obtained from the screening tests show that the tests are reliable diagnostic tests when the results are carefully interpreted, and the medical personnel can be alerted of the prevalence of syphilitic infections.

In a study carried out in Gabon, antibodies against the treponema were looked for in the cerebrospinal fluid (CSF) in 13 children with active congenital syphilis (presence of specific IgM antibodies) and in 7 children with positive serologic reactions reflecting transplacental passage of maternal antibodies. Serologic reactions used included the VDRL test, the TPHA test, and the FTA-ABS IgG and IgM tests. Among the 13 children with syphilis, 7 had a positive FTA-ABS IgG test in the CSF; positivity of this test was not correlated with severity of clinical features, CSF protein levels or CSF cytologic findings. The TPHA test was positive in only four children and the VDRL test was consistently negative. These findings are similar to those reported in another group of patients with meningeal involvement proven by the demonstration of IgM in the CSF using recent techniques. Passage of antibodies into the CSF is possible (1 case in this study) but for safety patients with specific IgG in the CSF should be given penicillin in a dosage that provides treponema-killing levels in situ (100,000 U/kg/d). Use of this dosage is recommended whenever sensitive techniques for CSF analysis are not available.

The action of papain and bromelain, prepared over a pH range from 4.6 to 8.6, was evaluated for the ability to render red cells agglutinable by five incomplete antibodies of differing blood group specificities using a two-stage technique. The optimal pH for treatment of red cells by activated papain or bromelain was between 5.4 and 5.8. Above this pH range, a fall in serological sensitivity was apparent which was much more pronounced with papain than with bromelain. The optimal pH for enzyme treatment of red cells can be achieved in two-stage techniques, but not in one-stage techniques due to the buffering effect of serum proteins.

Methods of quality control of some major haematological techniques are described. These methods have been applied in haematology laboratories serving a population of 2 million using existing facilities for preparation and transport of the necessary materials.

Results from the Finnish interlaboratory proficiency testing programme in immunohaematology from 1976 to 1978 are reviewed. The results show excellent accuracy of ABO grouping (100% correct). In Rh (D) grouping the detection of weak D antigen (Du) offered difficulties due to insufficient methodology. Also a sample from a donor with a positive direct antiglobulin reaction created confusion in Rh (D) grouping. The screening of atypical antibodies in serum was performed excellently (100% correct); the antibody coating of red cells, however, was detected by only 83.3% of the participants. The accuracy of compatible crossmatches was good (on average 98.7% correct); the accuracy of incompatible crossmatches, however, was poorer (on average 88.1% correct). A considerable methodological variation in compatibility testing is suggested to be responsible for the poor performance. The performance of individual laboratories seemed to correlate with their position in the health service organization, and with the level of internal quality control procedures.

Seven proficiency tests in compatibility testing were issued in 1979 to 1980. In each exercise participants were required to test five sera, most of which contained alloantibodies, against three samples of red cells by three designated techniques, namely agglutination in saline at room temperature, agglutination in albumin at 37 degrees C and the antiglobulin test at 37 degrees C. Comparability was achieved by scoring of results. Incompatibilities were missed by 3.5 to 22% of participants in five exercises in which undiluted antibodies were issued. There was no significant improvement in performance over two years. Antibodies which were issued diluted, but detectable by antiglobulin test, were missed with high frequency.

Surveys of antiglobulin test procedures and reagents were undertaken in 1979-1980 as part of a national external quality assessment scheme in compatibility testing. An extraordinary lack of standardization was revealed. In addition, practices underwent considerable changes over this period. The use of tube and of low ionic strength solution (LISS) techniques increased whilst the use of tile and of albumin-antiglobulin techniques declined. Performance in compatibility test exercises was significantly better with tube techniques than with tile techniques in 9/22 incompatibilities. Performance with LISS techniques was occasionally significantly better than with normal ionic strength techniques. Performance with albumin-antiglobulin techniques was occasionally significantly worse than in the absence of albumin. To varying extents significant relationships were found between performance and cell concentration, serum/cell concentration ratio, antiglobulin reagent and method of reading the results.