Screening for human immunodeficiency virus using a newly developed fourth generation lateral flow immunochromatography assay.

BACKGROUND: High sensitivity for detection of HIV-1 p24 antigen allows for early detection of primary HIV-1 infections. OBJECTIVES: To evaluate the detection sensitivity and specificity of the Daina Screen® HIV Combo assay using clinical specimens in Japan where the pretest probability (prevalence) is low. STUDY DESIGN: We screened 17,373 preoperative outpatient blood samples using 4th generation lateral flow immunochromatography Daina Screen® HIV Combo assay for simultaneously detecting anti-HIV-1/2 and HIV-1 p24 antigen. RESULTS: Of the samples tested, 24 were positive for HIV-1 p24 antigen and 49 for HIV-1/2 antibody. Of the 49 samples, 36 were WB and HIV-1 RNA negative, 10 were WB and HIV-1 RNA positive, and 3 were WB positive, HIV-1 RNA negative, and in-house HIV-1 proviral DNA positive. RT-PCR revealed that of the 24 samples that were p24 antigen positive, one sample was HIV-1 RNA positive, which was reconfirmed using an in-house HIV-1 provirus DNA assay. From the 17,300 HIV-1 p24 antigen and anti-HIV-1/2 negative samples, pools containing 10 negative samples each were tested for HIV-1 by RT-PCR; all results were negative. CONCLUSION: The Daina Screen® HIV Combo assay had a sensitivity and specificity of 100% and 99.7%, respectively, which sufficiently detected HIV infection in the cohort.

[Performance Assessment of a Newly Developed Rapid Diagnostic Reagent for Human Immunodeficiency Virus].

Extremely early diagnosis of human immunodeficiency virus (HIV) infection has been considered highly important for its treatment. We conducted a performance assessment of a newly developed rapid diagnostic reagent for HIV by using a fourth-generation immunochromatographic assay (Alere HIV Combo). We used whole-blood, plasma, and serum samples obtained from 250 Japanese adults who visited the Kawasaki Medical School Hospital and underwent HIV screening tests. We also used 12 types of commercial HIV-1 sero- conversion panels and World Health Organization standard antigens. This method, which has a detection sensitivity of 100% and a specificity of 99.3%, was as accurate as the chemiluminescent immunoassay (CLIA) method. In a sensitivity test using seroconversion panels in the early phase of infection, the mean duration until positive conversion was 19.3 days. With this method having a high detection sensitivity for HIV-1p24 antigen, the results from whole-blood samples were the same as those from plasma and serum samples. Therefore, it can be considered as a useful rapid measurement method for general practice.

Successful treatment of meningoencephalitis caused by methicillin-resistant Staphylococcus aureus with intravenous linezolid in an allogeneic cord blood stem cell transplant recipient.

Methicillin-resistant Staphylococcus aureus (MRSA) is an infectious pathogen that commonly occurs after stem cell transplantation. We report a case of meningoencephalitis with multiple abscess formation caused by MRSA, which occurred in a 62-y-old female soon after allogeneic cord blood transplantation, and which was successfully treated by the administration of intravenous linezolid.