False-positive ELISA for human immunodeficiency virus after influenza vaccination

John Cunningham Virus and Progressive Multifocal Leukoencephalopathy: A Falsely Played Diagnosis

Progressive Multifocal Leukoencephalopathy (PML) is a possibly fatal demyelinating disease and John Cunningham Polyomavirus (JCPyV) is believed to cause this condition. The so-called JCPyV was initially reported in lymphoma and Human Immunodeficiency Virus (HIV) cases, whereas nowadays, its incidence is increasing in Multiple Sclerosis (MS) cases treated with natalizumab (Tysabri). However, there are conflicting literature data on its pathology and diagnosis, whereas some misdiagnosed reports exist, giving rise to further questions towards the topic. In reality, the so-called PML and the supposed JCPyV are not what they seem to be. In addition, novel and more frequent PML-like conditions may be reported, especially after the Coronavirus Disease 2019 (COVID-19) pandemic.

Factors associated with false-positive results from fingerstick OraQuick ADVANCE rapid HIV 1/2 antibody test

OBJECTIVE

Identify factors associated with false-positive rapid HIV antibody tests.

DESIGN

This retrospective cohort study with nested case-controls involved patients tested for HIV by Boston Medical Center (BMC) affiliates.

METHODS

Cases had a reactive fingerstick OraQuick ADVANCE rapid HIV 1/2 antibody test and a negative Western blot. Controls had nonreactive rapid tests. We compared the prevalence of HIV risk factors between cases and the total nonreactive population and the prevalence of other clinical factors between cases and controls.

RESULTS

Of the 15 094 tests, 14 937 (98.9%) were negative and 11 (0.07%) were false positives (specificity of 99.9%). Cases were more likely to have had an HIV-infected sex partner and to be tested at certain sites compared to true negatives. More cases than controls had O-negative blood type.

CONCLUSION

O-negative blood type and sex with an HIV-infected person may increase false-positive HIV fingerstick results. More targeted studies should examine these risk factors.

New challenges for the diagnosis of feline immunodeficiency virus infection

Vaccination of cats against feline immunodeficiency virus (FIV) with a whole-virus vaccine results in rapid and persistent production of antibodies that are indistinguishable from those used for diagnosis of FIV infection. There are no diagnostic tests available for veterinary practitioners at the present time to resolve the diagnostic dilemma posed by use of whole-virus vaccines for protection of cats against FIV. There is a great need for development of commercially available rapid diagnostic tests that conform to differentiation of infected from vaccinated animals standards.

Transmission of drug-resistant HIV after an occupational exposure despite postexposure prophylaxis with a combination drug regimen

We documented a case of occupational human immunodeficiency virus (HIV) despite postexposure prophylaxis (PEP) with a combination drug regimen after percutaneous injury with a needle from a sharps disposal container in the hospital room of an HIV-infected patient. This failure of PEP with a combination drug regimen may have been related to antiretroviral drug resistance, other factors, or both. This case highlights the importance of preventing injury to prevent occupational transmission of HIV.

Human immunodeficiency virus testing and counseling: nuts and bolts

The human immunodeficiency virus poses an increasing health hazard to women. Physicians must recognize this risk and evaluate their patients for human immunodeficiency virus. Because of general increased awareness and the recommendations that all prenatal patients be offered human immunodeficiency virus testing and counseling, more and more women will be tested, yet counseling has not become a routine aspect in the evaluation of patients. This article reviews the key components of human immunodeficiency virus testing and counseling, including test interpretation, risk assessment, risk reduction, and pretest and posttest counseling. Familiarity with these areas should enable the practitioner to feel comfortable in providing this service.

False-positive hepatitis B surface antigen screening test results in patients receiving granulocyte-colony-stimulating factor

BACKGROUND

Granulocyte-colony-stimulating factor (G-CSF) is used for the mobilization of progenitor cells and granulocytes. False-positive hepatitis B surface antigen (HBsAg) enzyme-linked immunosorbent assays (ELISAs) (NML) from one manufacturer in individuals receiving G-CSF have been observed.

STUDY DESIGN AND METHODS

Sixty-six autologous peripheral blood progenitor cell donors from 1994 were retrospectively reviewed. Donors typically received 5 to 10 micrograms of G-CSF per kg subcutaneously for 5 days before collection. Additional ELISA dilutional studies (1-in-10, 1-in-100, 1-in-1000) with known HBsAg-negative serum were made with G-CSF. Testing was performed by the University of North Carolina, the American Red Cross in Charlotte, NC, or the National American Red Cross, Washington, DC.

RESULTS

Of the 66 patients, none reacted for antibody to hepatitis B core antigen, and 30 (45%) had a positive reaction in the ELISA. Surface antigen positivity was "confirmed" on 6 of the 30 patients by neutralizing ELISA reactivity with an antibody to HBsAg test from the same manufacturer. In all cases, the clinical presentation was not suggestive of hepatitis, and these individuals were not at high risk for hepatitis B. Twenty-seven of the 30 cases were tested with a monoclonal HBsAg ELISA (AUSZYME) from another manufacturer in the peridonation period and did not react. In 1994, 256 autologous whole-blood donors not receiving G-CSF were similarly tested and only 1 (0.4%) had a positive reaction with the second manufacturer's HBsAg ELISA (p < 0.001). Of this group, 41 patients with histories of malignancy were identified, which is comparable to the history of the peripheral blood progenitor cell donors in this study, and none of these blood donors tested positive for HBsAg (p < 0.001). Dilutional studies with G-CSF produced no reactions.

CONCLUSION

The NML HBsAg ELISA studied has an unacceptably high false-positive rate in patients or donors receiving G-CSF. The false reactivity of this assay appears to be an indirect consequence of G-CSF administration, which can also lead to spurious confirmation by the HBsAg neutralization assay from the same manufacturer.

PCR as a confirmatory test for human immunodeficiency virus type 1 infection in individuals with indeterminate western blot (immunoblot) profiles

A combination of two PCR systems which amplify human immunodeficiency virus type 1 (HIV-1) gag and pol DNA was used to elucidate the HIV-1 infection status of a group of individuals screening positive for anti-HIV but having indeterminate Western blot (immunoblot) profiles. The results obtained suggest PCR could be used to resolve such cases.