The role of confirmatory tests in the diagnosis of primary aldosteronism.

Confirmatory tests for diagnosis of primary aldosteronism (PA) play an important role in sparing patients with a false-positive aldosterone-to-renin ratio (ARR) screening test from undergoing invasive subtyping procedures. We recommend that patients with a positive ARR test should undergo at least one confirmatory test to confirm or exclude the diagnosis of PA before directly proceeding to subtype studies, except for patients with significant PA phenotypes, including spontaneous hypokalemia, plasma aldosterone concentration >20 ng/dL plus plasma renin activity below a detectable level. Although a gold standard confirmatory test has not been identified, we recommend that saline infusion test and captopril challenge test, which were widely used in Taiwan. Patients with PA have been reported to have a higher prevalence of concurrent autonomous cortisol secretion (ACS). ACS is a biochemical condition of mild cortisol overproduction from adrenal lesions, but without the typical clinical features of overt Cushing's syndrome. Concurrent ACS may result in incorrect interpretation of adrenal venous sampling (AVS) and may lead to adrenal insufficiency after adrenalectomy. We recommend screening for ACS in patients with PA scheduled for AVS examinations as well as for adrenalectomy. We recommend the 1-mg overnight dexamethasone suppression test as screening method to detect ACS.

Bacteria assisted green synthesis of copper oxide nanoparticles and their potential applications as antimicrobial agents and plant growth stimulants.

Copper oxide nanoparticles (CuO-NPs) have piqued the interest of agricultural researchers due to their potential application as fungicides, insecticides, and fertilizers. The Serratia sp. ZTB29 strain, which has the NCBI accession number MK773873, was a novel isolate used in this investigation that produced CuO-NPs. This strain can survive concentrations of copper as high as 22.5 mM and can also remove copper by synthesizing pure CuO-NPs. UV-VIS spectroscopy, DLS, Zeta potential, FTIR, TEM, and XRD techniques were used to investigate the pure form of CuO-NPs. The synthesized CuO-NPs were crystalline in nature (average size of 22 nm) with a monoclinic phase according to the XRD pattern. CuO-NPs were found to be polydisperse, spherical, and agglomeration-free. According to TEM and DLS inspection, they ranged in size from 20 to 40 nm, with a typical particle size of 28 nm. CuO-NPs were extremely stable, as demonstrated by their zeta potential of -15.4 mV. The ester (C=O), carboxyl (C=O), amine (NH), thiol (S-H), hydroxyl (OH), alkyne (C-H), and aromatic amine (C-N) groups from bacterial secretion were primarily responsible for reduction and stabilization of CuO-NPs revealed in an FTIR analysis. CuO-NPs at concentrations of 50 µg mL-1 and 200 µg mL-1 displayed antibacterial and antifungal activity against the plant pathogenic bacteria Xanthomonas sp. and pathogenic fungus Alternaria sp., respectively. The results of this investigation support the claims that CuO-NPs can be used as an efficient antimicrobial agent and nano-fertilizer, since, compared to the control and higher concentrations of CuO-NPs (100 mg L-1) considerably improved the growth characteristics of maize plants.

International multicenter survey on screening and confirmatory testing in primary aldosteronism.

OBJECTIVE: Primary aldosteronism (PA) is one of the most frequent causes of secondary hypertension. Although clinical practice guidelines recommend a diagnostic process, details of the steps remain incompletely standardized. DESIGN: In the present SCOT-PA survey, we have investigated the diversity of approaches utilized for each diagnostic step in different expert centers through a survey using Google questionnaires. A total of 33 centers from 3 continents participated. RESULTS: We demonstrated a prominent diversity in the conditions of blood sampling, assay methods for aldosterone and renin, and the methods and diagnostic cutoff for screening and confirmatory tests. The most standard measures were modification of antihypertensive medication and sitting posture for blood sampling, measurement of plasma aldosterone concentration (PAC) and active renin concentration by chemiluminescence enzyme immunoassay, a combination of aldosterone-to-renin ratio with PAC as an index for screening, and saline infusion test in a seated position for confirmatory testing. The cutoff values for screening and confirmatory testing showed significant variation among centers. CONCLUSIONS: Diversity of the diagnostic steps may lead to an inconsistent diagnosis of PA among centers and limit comparison of evidence for PA between different centers. We expect the impact of this diversity to be most prominent in patients with mild PA. The survey raises 2 issues: the need for standardization of the diagnostic process and revisiting the concept of mild PA. Further standardization of the diagnostic process/criteria will improve the quality of evidence and management of patients with PA.

To Be or Not to Be an OXA-48 Carbapenemase.

Since the first description of OXA-48, more than forty variants have been recovered from Enterobacterales isolates. Whereas some OXA-48-related enzymes have been reported as conferring similar resistance patterns, namely, the hydrolysis of carbapenems and penicillins with very weak or almost no activity against expanded-spectrum cephalosporins, some have reduced carbapenem and temocillin hydrolysis, and others hydrolyze expanded-spectrum cephalosporins and carbapenems only marginally. With such drastic differences in the hydrolytic profile, especially of carbapenems, it becomes urgent to establish hydrolytic cutoffs in order to determine when an OXA-48-like enzyme may be considered as a carbapenemase or not. With this aim, the coefficient of activity for imipenem (kcat/Km) was determined for a total of 30 enzymes, including OXA-48, OXA-48-like natural variants, and OXA-48 synthetic mutants. In addition, six different methods for the detection of carbapenemase-producers were performed. The coefficients of activity for imipenem for all the different enzymes went from 550 mM-1·s-1 to 0.02 mM-1·s-1. In order to match the coefficient of activity results with the biochemical confirmatory tests, we suggest the value of 0.27 mM-1·s-1 as the cutoff above which an OXA-48 variant may be considered a carbapenem-hydrolyzing enzyme.

Especificidad de pruebas rápidas y confirmatorias de vih/sida de pacientes femeninas en edades reproductivas del hospital general esmeraldas sur / Specificity of rapid and confirmatory hiv / aids tests of female patients in reproductive ages of the General Hospital Esmeraldas Sur

EL Virus de Inmunodeficiencia Humana, constituye un grave problema de salud a nivel mundial. El VIH, es una patología que ataca las células CD4 del sistema inmunitario, ocasionando un desperfecto en el sistema inmune, lo cual hace más fácil la llegada de infecciones o enfermedades oportunistas. Objetivo: Conocer la especificidad de las pruebas rápidas y pruebas confirmatorias de pacientes con VIH en edades reproductivas del Hospital General Esmeraldas Sur, en el área de laboratorio clínico. Metodología: Es un estudio Cuantitativo, de corte longitudinal retrospectivo, con alcance descriptivo, que permitió ordenar, interpretar y tabular los resultados de las pruebas rápidas y pruebas confirmatorias de VIH/sida de pacientes femeninas en edades reproductivas. Evidenciándose la falta de información en el registro de pacientes con VIH/sida del HGES, de los datos estadísticos, en 49 pacientes femeninas registras en el HGES. Resultados: El estudio indica que existe un predominio de pacientes con VIH/sida 30 casos corresponde a pacientes al grupo etario ≤ 30 años, seguido por 12 casos que corresponde a pacientes del grupo etario ≤ 40 años, mientras que los pacientes del grupo etario ≤ 45 representan un 8% (4 casos) y el 6% (3 casos) corresponde a pacientes ≤ 20. El 61% corresponde a ≤ 30 años, en segundo lugar, con el 25% las ≤ 40 años. Conclusiones: Los registros observados en el HGES, durante el proceso de investigación, no fueron suficientes para alcanzar el objetivo propuesto, para tal efecto es necesario disponer de los registros completos de los pacientes con VIH/sida en todas las pruebas, según en algoritmo de la OMS. Además, de brindar confianza a la ciudadanía con resultados de calidad, se debe utilizar recursos tecnológicos y demás instrumentos que permitan al profesional de salud, dar un diagnóstico correcto y oportuno. Todo enmarcado en la ética principal, la conservación de la vida(AU)

The Human Immunodeficiency Virus constitutes a serious health problem worldwide. HIV is a pathology that attacks the CD4 cells of the immune system, causing damage to the immune system, which makes it easier for infections or opportunistic diseases to arrive. Objective: To know the specificity of the rapid tests and confirmatory tests of patients with HIV in reproductive ages of the General Hospital Esmeraldas Sur, in the clinical laboratory area. Methodology: It is a quantitative study, retrospective longitudinal section, with descriptive scope, which allowed ordering, interpreting and tabulating the results of rapid tests and confirmatory tests of HIV / AIDS of female patients of reproductive ages. Evidence of the lack of information in the registry of patients with HIV / AIDS of the HGES, of the statistical data, in 49 female patients registered in the HGES. Results: The study indicates that there is a predominance of patients with HIV / AIDS. 30 cases correspond to patients in the age group ≤ 30 years, followed by 12 cases corresponding to patients in the age group ≤ 40 years, while patients in the age group ≤ 45 represent 8% (4 cases) and 6% (3 cases) correspond to patients ≤ 20. 61% correspond to ≤ 30 years, secondly, with 25% those ≤ 40 years. Conclusions: The records observed in the HGES, during the research process, were not sufficient to achieve the proposed objective, for this purpose, it is necessary to have complete records of patients with HIV / AIDS in all tests, according to the algorithm of The OMS. In addition, to provide confidence to the public with quality results, technological resources and other instruments must be use that allow the health professional to give a correct and timely diagnosis. All framed in the main ethic, the conservation of life(AU)

Evaluation of various confirmatory tests for the diagnosis of aldosterone-producing adenoma.

INTRODUCTION: Adrenal venous sampling is useful for discriminating unilateral and bilateral hypersecretion in patients with primary aldosteronism, but it is relatively invasive. To determine the site of hypersecretion more non-invasively, we evaluated predictors of unilateral hypersecretion. MATERIALS AND METHODS: We evaluated the baseline characteristics and the results of confirmatory tests of 123 patients with primary aldosteronism who underwent adrenal venous sampling. RESULTS: Unilateral hypersecretion was identified in 22.0%. The plasma aldosterone concentration and aldosterone-renin ratio were significantly higher and serum potassium concentration and plasma renin activity were significantly lower in patients with unilateral hypersecretion. Plasma aldosterone concentrations after captopril challenge test, saline infusion test and rapid adrenocorticotropic hormone stimulation test were significantly higher among patients with unilateral hypersecretion. The plasma aldosterone concentration reduction ratio in saline infusion test and plasma aldosterone concentration elevation ratio during rapid adrenocorticotropic hormone stimulation test were significantly higher in patients with unilateral hypersecretion. However, areas under the curve for these parameters were not superior to the values after confirmatory tests. CONCLUSIONS: The plasma aldosterone concentration values after captopril challenge test, saline infusion test and rapid adrenocorticotropic hormone stimulation test were useful for identifying patients with unilateral hypersecretion. However, value changes or ratios during confirmatory tests are less useful for this aim.

Utility of grey zone testing strategy in transfusion transmissible infection testing in blood bank is of limited value!

Several blood banks use grey zone (GZ) phenomenon (defined as samples with optical density within 10% below the cut off in enzyme immuno-assay [EIA]/chemiluminescence immunoassay [CLIA]) to further augment blood safety. There is paucity of data regarding usefulness of GZ sample and its application in Transfusion Transmissible Infection (TTI) screening procedures in blood transfusion services. We looked at our GZ sample results and their confirmatory test results to verify if it adds to blood safety in our set-up? We performed a prospective analytical study on blood donors' samples over two years. All the donors' samples were screened for TTI using CLIA. Samples with signal/cut-off ratio between ≥0.90 and <1.00 were classified under GZ. They were re-tested in duplicate and submitted to confirmatory testing: Neutralization Test for HBsAg, Immunoblot for HCV, and Western blot for HIV. Among the 50,064 blood donors donating the blood during study period, 573 (1.14%) donors were reactive for HBsAg, HCV, and HIV. Forty-seven (0.1%) TTI samples were GZ, but none was "confirmed positive." The utility of GZ testing seems to be limited. However, this may be continued for sake of "erring on the side of caution" and since this only results in negligible wastage (0.1%) of blood units.

Parameters of captopril challenge test can predict results of other confirmatory tests for primary aldosteronism and propose the next test to be done.

In Japan, primary aldosteronism (PA) is diagnosed if any one of the captopril challenge test (CCT), saline infusion test (SIT), furosemide-upright test (FUP), and oral salt-loading test (OST) is positive. The present study aimed to investigate if parameters of CCT, the safest confirmatory test, could predict decisions of other tests and propose the next test to diagnose PA in CCT-negative patients. In a cross-sectional design, 142 patients, who were referred to our hospital for the scrutiny of PA and underwent at least two confirmatory tests, were enrolled. While 123 patients underwent all of the CCT, SIT, and FUP, the OST was successfully done in only six patients and excluded from further analyses. CCT parameters showing correlations of higher degrees with SIT and FUP parameters were selected, and their powers to predict SIT and FUP decisions were investigated by receiver operating characteristic analyses. Proposals of the next test based on the CCT parameters were validated with SIT and FUP decisions in subsets of CCT-negative patients divided by cut-offs of the CCT parameters. The plasma aldosterone concentration and plasma renin activity 60 min after the load of CCT (CCT60-PAC and CCT60-PRA) were selected, and CCT60-PAC ≤59.0 pg/mL and CCT60-PRA ≥1.05 ng/mL/h could predict negativities of SIT and FUP, respectively, with >95% specificities. Based on the validation, the present study suggested the SIT as the next test to be done if the CCT-negative patient belonged to the subset with CCT60-PAC >59.0 pg/mL and CCT60-PRA ≥1.05 ng/mL/h, otherwise the FUP should be selected.

Primary aldosteronism in a general population sample. The Czech post-MONICA study.

Purpose: Primary aldosteronism (PA) is considered the most common form of secondary hypertension, however, its prevalence, particularly in a general population, is still a matter of debate. The aim of our study was to evaluate the prevalence of PA in a randomly selected general population sample.Materials and methods: A total of 1940 individuals (1% population random sample) aged 25-64 years were screened for major cardiovascular risk factors in six districts of the Czech Republic. Hypertension was defined as a mean of two blood pressure readings ≥140/90 mmHg at one visit or taking antihypertensive medication. Within this population, 740 individuals were labelled as hypertensives and 650 of them sampled for the analysis of direct plasma renin and serum aldosterone. The diagnosis of PA was based on elevated serum aldosterone, low plasma renin and high aldosterone/renin (ARR) ratio and was also verified by a confirmatory test with saline infusion.Results: Positive ARR was found in 52 (8%) individuals (64% women, 36% men, however, due to substatntial proportion of reluctatnt participants to undergo a further work-up (27%), we could confirm the diagnosis of PA only in 13 of them (2%). Aldosterone-producing adenoma was found in one case only, seven patients had idiopathic type and five individuals refused potential surgical treatment therefore, adrenal venous sampling was not performed.Conclusion: Elevated serum aldosterone together with low renin and high ARR were found in 52 (8%) of hypertensives selected from a general population sample, however, the diagnosis of PA was confirmed only in 13 of them (2%). This study based on a general population survey highlighted the difficulty of conducting epidemiological studies on primary aldosteronism in a relatively healthy cohort part of whom did not provide the level of collaboration that is necessary to assess the true prevalence of this condition.

Performance evaluation of the Bio-Rad Geenius HIV 1/2 supplemental assay.

BACKGROUND: In the US, the HIV diagnostic algorithm for laboratory settings recommends the use of an HIV-1/HIV-2 differentiation supplemental assay after an initial reactive antigen/antibody (Ag/Ab) assay result. Since the discontinuation of the Multispot HIV-1/HIV-2 Rapid Test (MS), the Geenius HIV-1/2 Supplemental assay (Geenius) is the only FDA-approved supplemental differentiation test. OBJECTIVE: We compared the performance of Geenius to MS and Western Blot (WB). STUDY DESIGN: The relative seroconversion plasma reactivity of Geenius and MS was assessed using a 50% cumulative frequency analysis from 17 HIV-1 seroconverters. In addition, previously characterized plasma specimens, 186 HIV-1 positive, 100 HIV-2 positive, and 93 Ag/Ab-positive/HIV-1 RNA-negative, were tested with Geenius v1.1 software. McNemar's test was used for paired comparison analysis. A subset of 48 specimens were retested with the upgraded Geenius v1.3 software. RESULTS: In HIV-1 seroconverters, the relative seroconversion reactivity was 2.5 and 2 days before the first positive HIV-1 WB for Geenius and MS, respectively. In HIV-1 positive samples, Geenius performed similarly to HIV-1 WB (p=0.1687) and MS (p=0.8312). In HIV-2 positive samples, Geenius underperformed compared to HIV-2 WB (p=0.0005) and MS (p=0.0012). When using the upgraded software among the HIV-1 positive and Ag/Ab-reactive/HIV-1 RNA-negative samples, gp140 reactivity decreased without affecting characterization of HIV-2 samples. CONCLUSIONS: With HIV-1 samples, Geenius, WB and MS performance was similar as supplemental tests. The updated Geenius software reduced false gp140 reactivity, but had no impact on identifying true HIV-2 infections. Further evaluation will assess the impact of the Geenius software update on final diagnostic interpretations.

False human cytomegalovirus IgG-positivity at prenatal screening.

BACKGROUND: An incorrect definition of immune status to human cytomegalovirus (HCMV) can lead to incorrect management of pregnant women. OBJECTIVES: Aims of the study were: i) to describe 10 cases of unconfirmed HCMV IgG-seroconversion in pregnancy; ii) to develop a panel of confirmatory tests to define HCMV serostatus; iii) to investigate the frequency of false IgG-positive results in pregnant women screened with the LIAISON®CMVIgGII automated assay. STUDY DESIGN: Blood samples from 10 pregnant women referred for HCMV IgG-seroconversion were examined to confirm/exclude a primary infection. In addition, samples were tested for HCMV IgG by immunoblotting, neutralization assay, and ELISA against gB, gH/gL/pUL128L and gH/gL/gO recombinant glycoproteins. LIAISON®CMVIgGII results obtained on 1158 pregnant women were reviewed and samples with low IgG titers were further investigated. RESULTS: A primary infection was excluded in the 10 women referred for HCMV IgG seroconversion. None of them was confirmed to be IgG-seropositive. Of the 1158 women prenatally screened by LIAISON®CMVIgGII, 678 (59%) were IgG-positive and, of these, 40 (5.9%) showed low levels of IgG (14-50 U/mL). Thirty-three women with low IgG-positivity were further tested by confirmatory tests and 11 (33.3%) were found to be non reactive to HCMV. CONCLUSIONS: At least 1.6% (11/678) women who tested positive with LIAISON®CMVIgGII were found to be seronegative when tested with confirmatory tests. These women should be informed to reduce the risk of a primary HCMV infection. Furthermore, should a congenital infection occur in any of these women, a maternal non-primary infection could be erroneously diagnosed.

[Modern look at the problems of investigation of antinuclear antibodies in systemic lupus erythematosus (literature review).]

In the review, topical aspects of the study of antinuclear antibodies (ANA) in systemic lupus erythematosus (SLE) are considered. ANA is the main serological marker of SLE. In the sera of patients with SLE, antibodies to DNA, histones, nucleosomes, extractable nuclear antigens (Sm, U1 ribonucleoprotein, Ro / SSA, La / SSB, ribosomal protein P), nucleolar antigens and other cellular structures are detected. The ANA study using indirect immunofluorescence on HEp-2 cells (IIF-HEp-2) is recommended as a standard screening test for the diagnosis of SLE. The use of automated systems for the interpretation of cellular fluorescent tests contributes to the standardization and improvement of the reproducibility of the IIF. A new international nomenclature of types of nuclear, nucleolar (nucleolar), cytoplasmic and mitotic luminescence of ANA in IIF-HEp-2, including 28 variants of anticell ("Anti-cell" - AC) patterns was developed. In the practice of clinical diagnostic laboratories, high-performance automated methods for the determination of ANA based on ELISA, immunoblot, fluorescent, chemiluminescent and multiplex immunoassay are widely used. New mono- and multiplex methods of solid-phase analysis are expediently used as confirmatory reflex tests for the detection of varieties of antigen-specific ANA in patients with SLE with positive results of IIF-HEp-2. Identification of ANA profiles using multiplex technologies is a useful tool for implementing a personalized approach to diagnosis, evaluation of activity, prognosis, clinical and immunological subtypes, and the effectiveness of SLE therapy. The need for an ANA study not only to confirm the diagnosis of SLE, but also to identify the disease in the early and preclinical stages with the intention to prevent the development of the pathological process is discussed. Detection of monospecific anti-DFS70 antibodies allows to exclude the diagnosis of SLE inANA IIF-HEp-2 positive subjects. Presented is a modern algorithm for testing ANA with SLE.

Phenotypical Variability in Bovine Spongiform Encephalopathy: Epidemiology, Pathogenesis, and Diagnosis of Classical and Atypical Forms.

After thirty years, bovine spongiform encephalopathy (BSE) still represents the biggest crisis in the field of food safety. Initially detected in the United Kingdom in 1986, BSE spread to many other countries all over the world, involving approximately 200,000 cattle. The origin of BSE is uncertain, but epidemiological studies suggest that the source was cattle feed prepared from prion-infected animal tissues. The implementation of the drastic measures, including the ban of meat and bone meal from livestock feed and the removal of specified risk material from the food chain, has eventually resulted in a significant decline of the epidemic. For many years, it was believed that the disease was caused by transmission of a single prion strain. However, since 2004 two types of BSE, with distinct phenotypical characteristics, have been detected in Italy and France. These atypical types are characterized by distinct Western Blot profiles of abnormal protease-resistant prion protein, named high-type (H-BSE) and low-type (L-BSE). At present, there is no comprehensive information about the origin of the atypical BSEs (sporadic vs. acquired), and data about the pathogenesis of both atypical forms are very limited as compared to the classical type (C-BSE). This chapter will provide a well-organized overview of what is known about classical and atypical BSE. It will review information on the main epidemiological features, pathogenesis, and the criteria for routine diagnosis based on rapid tests, histological, immunohistochemical, and Western blot analysis. Furthermore, a brief overview about the most recently in vitro techniques will be also provided.

Confirming the brain death diagnosis using brain CT angiography: experience in Tokat State Hospital.

OBJECTIVE: Fourteen brain death cases diagnosed in Mart 2012-May 2013 period in Tokat State Hospital were studied retrospectively. CT angiography experience about those cases was shared, and use of CT angiography in confirmation of brain death was discussed. MATERIAL AND METHODS: All 14 cases were patients on mechanical ventilator, who did not respond to medical and surgical treatments at intensive care unit and were diagnosed clinically with brain death. All of these patients had CT angiography as a confirmatory test using a 4-slice CT scanner in Radiology department in Tokat State Hospital. FINDINGS: Six of the patients were female and eight were male. All of them were referred from intensive care unit and had clinical brain death diagnosis before CT angiography. In the evaluation of CTA, four-point scoring involving opacification loss in both ICVs and cortical segments of MCA was used. CTA examinations confirmed brain death diagnoses in all patients who had clinical brain death diagnoses, and no confliction between CTA findings and clinical diagnoses was observed. CONCLUSION: Demonstrating the lack of cerebral circulation is a necessity for confirmation of brain death diagnosis. While conventional angiography remains the standard method, CTA emerged as an alternative method. In parallel to increase in prevalence of organ implants, CTA, a fast and efficient method, has been increasingly used in confirmation of brain death diagnoses.

Evaluation of the Bio-Rad Geenius HIV-1/2 test as a confirmatory assay.

OBJECTIVES: We have evaluated the recently Conformité Européenne (CE)-marked Bio-Rad Geenius human immunodeficiency virus (HIV)1/2 as a rapid and simple alternative to western blot for confirmation of HIV screening results. METHODS: A total of 160 serum samples were tested: 44 HIV-1 reactive samples by a fourth-generation Murex HIV Ag/Ab and/or Vidas HIV Duo Ultra, five HIV-2 reactive samples, 15 HIV-1 non-B subtype samples and 11 confirmed HIV-1 early seroconversion samples, 72 nonreactive samples, eight indeterminate samples by MP HIV BLOT 2.2 confirmed negative after follow-up and five low-reactive samples by enzyme immunoassay (EIA) negative by MP HIV BLOT 2.2. The samples were tested according to the manufacturer's guidelines. RESULTS: The overall sensitivity for Bio-Rad Geenius HIV1/2 assay was 92%. Five out of 11 early seroconversion samples were tested positive, four negative and two indeterminate. All HIV-1 non-B subtype samples were tested positive. Two out of the five HIV-2 reactive samples were tested positive HIV-2, two positive HIV-2 with HIV-1 cross-reaction and one HIV positive untypable. After excluding early seroconversion samples, the sensitivity of Bio-Rad Geenius HIV1/2 assay reached 100%. Overall specificity was 96%. All HIV negative serums by fourth-generation EIA were tested negative. All five low-reactive samples by EIA, negative by HIV BLOT 2.2 were tested negative by Bio-Rad Geenius HIV1/2. Two out of the eight indeterminate samples by MP HIV BLOT 2.2 that were confirmed negative after follow-up were tested indeterminate and one invalid, the other five were negative. After excluding these last 13 samples, the specificity of Bio-Rad Geenius HIV1/2 assay reached 100%. In comparison with MP HIV BLOT 2.2, the Bio-Rad Geenius HIV1/2 assay was markedly time saving, allowed full traceability, automatic reading and interpretation. CONCLUSIONS: The Bio-Rad Geenius HIV1/2 confirmatory system represents a reliable alternative to other confirmatory assays in HIV testing algorithms and provides clear improvement in quality management.

Determining Brain Death

Brain death is a clinical diagnosis. The three cardinal findings in brain death are coma or unresponsiveness, absence of brainstem reflexes, and apnea. The clinical examination of the brainstem includes testing of brainstem reflexes, determination of the patient's ability to breath spontaneously, and evaluation of the motor response to pain. Spontaneous and reflex movements originating from the spinal cord neurons may occur in brain-dead patients. An awareness of spinal reflexes may prevent delays in and misinterpretations of the brain-death diagnosis. In some countries including Korea, our country, confirmatory tests are required by law when determining brain death. However, a confirmatory test is not usually mandatory except for patients in whom specific components of clinical testing cannot be evaluated reliably.