Performance evaluation of a new fourth-generation HIV combination antigen-antibody assay.

Education and diagnostic tests capable of early detection represent our most effective means of preventing transmission of human immunodeficiency virus (HIV). The importance of early detection is underlined by studies demonstrating increased life expectancy following early initiation of antiviral treatment. The Elecsys(®) HIV combi PT assay is a fourth-generation antigen-antibody combination assay developed to allow earlier detection of seroconversion, and to have increased sensitivity and improved specificity. We aimed to determine how early the assay could detect infection compared with existing assays; whether all HIV variants could be detected; and the assay's specificity using samples from blood donors, routine specimens, and patients with potential cross-reacting factors. Samples were identified as positive by the Elecsys(®) assay 4.9 days after a positive polymerase chain reaction result (as determined by the panel supplier), which was earlier than the 5.3-7.1 days observed with comparators. The analytical sensitivity of the Elecsys(®) HIV combi PT assay for the HIV-1 p24 antigen was 1.05 IU/mL, which compares favorably with the comparator assays. In addition, the Elecsys(®) assay identified all screened HIV subtypes and displayed greater sensitivity to HIV-2 homologous antigen and antibodies to HIV-1 E and O and HIV-2 than the other assays. Overall, the specificity of the Elecsys(®) assay was 99.88 % using samples from blood donors and 99.81 % when analyzing unselected samples. Potential cross-reacting factors did not interfere with assay performance. The Elecsys(®) HIV combi PT assay is a sensitive and specific assay that has been granted the CE mark according to Directive 2009/886/EC.

Multicenter evaluation of a fully automated third-generation anti-HCV antibody screening test with excellent sensitivity and specificity.

Early detection of hepatitis C virus (HCV) is an important step in preventing progression to cirrhosis and hepatocellular carcinoma. Serologic assays for anti-hepatitis C (anti-HCV) antibody are valuable first-line tests in the screening and diagnosis of HCV infection. The aim of this multicenter study was to compare the Elecsys(®) Anti-HCV assay with alternative CE-marked Anti-HCV antibody assays against a range of samples that included 1,138 blood donors, 3,553 unselected routine daily specimens, and 46 pre-selected seroconversion panels. Specificity of the Elecsys Anti-HCV assay was 99.5% with blood donor samples and 99.4% with routine clinical specimens. These were similar to those obtained with the Prism(®) Anti-HCV, Architect(®) Anti-HCV assay, ADVIA(®) Centaur Anti-HCV assay and Vitros(®) Eci aHCV assays. Seroconversion sensitivity for the Elecsys Anti-HCV assay was similar to that of the Architect Anti-HCV, AxSYM HCV version 3.0, ADVIA Centaur Anti-HCV, and Vitros Eci aHCV assays. In fact, seroconversion testing on 46 commercially available panels showed that the difference in first detecting a positive blood sample was less than one day between assays (not statistically significant). The Elecsys Anti-HCV assay as well as the Architect, Prism, and Vitros Anti-HCV immunoassays revealed a seroconversion sensitivity of 100%, whereas the ADVIA Centaur HCV immunoassay showed a sensitivity of only 97.5% (39/40). Overall, the performance of the Elecsys Anti-HCV assay was similar to the performances of the comparator CE-marked Anti-HCV antibody assays.

Immunity to poliovirus among children and the elderly in north-east Italy.

INTRODUCTION: Italy and Europe were declared polio-free in June 2002, but increasing migration, even from undeveloped countries where polio still exists, may lead to a come-back of circulating poliovirus (PV) and infection in previously polio-free areas. It is consequently advisable to continue to monitor the immunity of the population in polio-free areas. The aim of this study was to assess the current prevalence of neutralizing antibodies in recently-immunized children and in elderly people who were never vaccinated. METHODS: Sera from 511 healthy subjects resident in the Veneto Region were examined to assay their antibody titer for PV 1, 2 and 3, using the microneutralization test. Data were analyzed by chi-squared test, Student's t-test and linear regression analysis, using EPI-Info 2000 supplied by the Centers for Disease Control and Prevention (Atlanta, GA, USA). RESULTS: Neutralizing antibodies in group A (231 subjects aged 1-17 years) showed significantly higher geometric mean titers (GMTs) than in group B (280 subjects aged 65-100 years) for all three PV serotypes (P < 0.001). Nobody simultaneously lacked neutralizing antibodies for all three serotypes. There were no difference between the two groups in terms of male/female GMTs for the three PV Antibodies decreased with time since vaccination, but the difference was only significant for PV 3. GMTs were lower in the elderly, with no significant difference among the three PV. DISCUSSION: The population examined showed a good level of protection against the three PV strains: both groups A (vaccinated) and B (naturally immunized) revealed a valid immunity to poliovirus. CONCLUSION: Immunization programs and immunity status population screening are still advisable until polio has been world-wide eradicated.

Cell-mediated immunity and condylomatosis.

Cell-mediated response in 60 patients affected by acuminated condylomas has been studied; this was investigated with aspecific in vivo tests (intradermal-reaction with tuberculin, trichophytin, candidine) and by in vitro tests (blood test with cell count, lymphocyte typing, serum proteins, serum immunoglobulin) and was compared with a control group. The results obtained confirm the hypothesis that condylomas acuminata usually occurs in patients with well-preserved cell-mediated immunity.

[Allergy to a copper-medicated IUD: a case report]. / Considerazioni su di un caso di allergia a IUD medicato al rame.

PIP: The article documents a clinical case involving allergy to the copper IUD. A 28-eight year old woman, with a normal family medical history, received a copper-medicated IUD (MLCu250) in March 1985, that initially was well tolerated both gynecologically and psychologically. After approximately 2 months, palpebral and perioral edema occurred that regressed following antihistamine treatment. After 5-6 months, erythema and an intense itching along with pruriginous symptoms spreading all over her body occurred at menstruation time. These symptoms responded to antihistamine and cortisone, but reappeared after discontinued treatment. The patient received the patch test revealing a pronounced positivity to copper sulphate. Other clinical tests revealed that cupremia during the acute phases was 110g/100 ml. (fully within the normal limits). A direct allergic, but nontoxic connection to the presence of IUD was established. Numerous studies have revealed that the copper contained in IUD is liberated in the uterine cavity in the form of ions and it is hypothesized during menstruation released into the blood stream, which is supported by the fact that allergic episodes were verified during menstrual bleeding. However, skin complications could also be the result of absorption and diffusion of plasmatic proteins in the blood stream whose molecular configurations are altered in the endometrium as a result of the copper ions, thus causing allergic reactions. Allergies should be considered a possibility with the IUD, but it is not advised to perform allergometric tests in all patients who receive one.^ieng