Ana Machuca

Window-period human immunodeficiency virus transmission to two recipients by an adolescent blood donor

BACKGROUND:  Pooled NAT and donor screening have reduced the diagnostic window period for HIV in the blood donor population to approximately 10 to 15 days. This report describes two cases of transfusion‐acquired HIV infection and verification of transmission from the donor to the recipients, and attempts to identify how the 18‐year‐old donor acquired her infection.

In vivo fluctuation of HTLV-I and HTLV-II proviral load in patients receiving antiretroviral drugs.

Summary: HTLV‐I and HTLV‐II infect T lymphocytes. A high HTLV‐I proviral load in peripheral blood mononuclear cells (PBMCs) has been associated with a higher risk of neurologic disease. For HTLV‐II, large numbers of infected lymphocytes might contribute to accelerate the immunodeficiency and increase the risk of neuropathy in HTLV‐II/HIV‐1 coinfected people. We have examined the impact of antiretroviral drugs on HTLV proviral load, testing longitudinal samples collected from 1 HTLV‐I infected patient suffering HTLV‐I‐associated myelopathy (HAM), and two HTLV‐II/ HIV‐1 coinfected subjects. The HAM patient showed a reduction greater than 2 log in the peripheral proviral load after being treated with zidovudine and lamivudine. In contrast, potent antiretroviral treatment in HIV‐1/HTLV‐II coinfected carriers produced an initial increase in the HTLV proviral load, which was followed by a reduction greater than 1 log thereafter. In conclusion, antiretroviral drugs seem to reduce HTLV proviral load, although in HIV‐1 coinfected persons a transient increase in HTLV proviral load could reflect the rapid blocking of HIV‐1 replication occurring in response to therapy, thus causing an increase in the number of circulating T lymphocytes carrying HTLV proviral DNA.

Prevalence of HTLV infection in pregnant women in Spain

Objective: To estimate the prevalence of HTLV infection among pregnant women in Spain. Methods: A commercial ELISA incorporating HTLV-I and HTLV-II antigens was used for HTLV antibody screening. Repeatedly reactive samples were further examined by western blot. Moreover, confirmation with PCR was performed when cells were available. Results: 20 366 pregnant women in 12 different Spanish cities were tested in a 3 year period (July 1996 to August 1999). 32 samples were repeatedly reactive by ELISA, and 10 of them were confirmed as positive by western blot (eight for HTLV-II and two for HTLV-I). In addition, three of 13 women who had an indeterminate western blot pattern yielded positive results for HTLV-II by PCR. All 11 HTLV-II infected women had been born in Spain, and all but one were former drug users. Seven of them were coinfected with HIV-1. One HTLV-I infected woman was from Peru, where HTLV is endemic and where she most probably was infected during sexual intercourse. Conclusion: The overall prevalence of HTLV infection among pregnant women in Spain is 0.064% (13/20 366), and HTLV-II instead of HTLV-I is the most commonly found variant. A strong relation was found among HTLV-II infection and specific epidemiological features, such as Spanish nationality and injecting drug use. Although HTLV-II can be vertically transmitted, mainly through breast feeding, both the low prevalence of infection and its lack of pathogenicity would not support the introduction of HTLV antenatal screening in Spain.

Clearance of human herpesvirus type 8 viraemia in Hiv-1-positive patients with Kaposi's sarcoma treated with liposomal doxorubicin

ObjectiveTo assess the impact of liposomal doxorubicin on human herpesvirus type 8 (HHV-8) cell viraemia in HIV-infected patients with Kaposis sarcoma. DesignProspective, non-controlled, multicenter study. MethodsThe presence of HHV-8 DNA was investigated by polymerase chain reaction in peripheral blood mononuclear cells from 46 HIV-positive patients with Kaposis sarcoma. Samples were tested at baseline and every 3 months during treatment with liposomal doxorubicin. CD4 cell counts, plasma HIV RNA, and clinical outcome were recorded at baseline and at follow-up visits. ResultsHHV-8 sequences were detected in 32 (70%) patients at baseline. No significant differences were found between subjects with HHV-8 positive and negative results. The proportion of patients with positive HHV-8 viraemia decreased to 38% (10 of 26) after 3 months of treatment with liposomal doxorubicin (P  < 0.01). Overall, 12 of 22 (57%) subjects with positive HHV-8 cell viraemia at baseline became negative during the treatment period. However, in one of them HHV-8 reappeared 8 months later despite being on therapy. On the other hand, six of eight subjects with negative HHV-8 at baseline remained negative thereafter. There were no significant changes in plasma HIV RNA, total lymphocyte, or CD4 cell counts during the treatment period. Clinical response of Kaposis sarcoma to liposomal doxorubicin and clearance of HHV-8 viraemia did not correlate well. ConclusionsHHV-8 cell viraemia significantly decreased during treatment with liposomal doxorubicin in HIV-infected patients with Kaposis sarcoma, although the clinical response and HHV-8 clearance did not correlate well.

HIV type 2 primary isolates induce a lower degree of apoptosis "in vitro" compared with HIV type 1 primary isolates.

To determine whether subtypes of HIV-1 and HIV-2 vary in their ability to induce T cell apoptosis in vitro, human peripheral blood mononuclear cells (PBMC) from healthy donors and CEM.NKR-CCR5 cells were infected with a variety of HIV-1 and HIV-2 isolates in vitro. Apoptotic cell levels and chemokine and cytokine production were analyzed. Significant variations in cytopathic effects following in vitro infection with primary isolates of HIV-1 or HIV-2 subtypes were observed in PBMCs. The percent of apoptotic cells from each individual ranged from 2 to 78% after HIV-1 infection and from 0 to 28% after HIV-2 infection (p < 0.01). We did not observe significant differences in the degree of apoptosis induced among cells infected with different HIV-1 group M subtypes or group O virus, nor among cells infected with different HIV-2 isolates. However, HIV-2 induced significantly lower degree of apoptosis overall in PBMC and CEM.NKR-CC5 cells when compared with HIV-1 subtypes (p < 0.0001). No significant differences were observed in the production of chemokines, such as RANTES, MIP-1alpha, and MIP-1beta, and cytokines, such as TNF-alpha and TNF-beta when PBMC cultures were infected with different HIV-1 subtype viruses, or HIV-2 isolates. In conclusion, HIV-2 isolates induced significantly lower levels of T cell apoptosis in both PBMC and CEM.NKR-CCR5 cells than HIV-1 isolates. No differences in T cell apoptosis levels were seen between different subtypes of HIV-1 group M or group O isolates. This is consistent with the mild clinical course of infection with HIV-2 that has been reported relative to that observed with HIV-1.

Riesgo residual de transmisión del virus de la inmunodeficiencia humana (VIH) en bancos de sangre e impacto del cribado con pruebas de detección de ácidos nucleicos

El riesgo actual de adquirir una infeccion por el virus de la inmunodeficiencia humana (VIH) a traves de la recepcion de una transfusion de sangre o derivados sanguineos es muy reducido en la mayoria de los paises desarrollados. El elevado nivel de bioseguridad alcanzado en las transfusiones de sangre en los ultimos anos se debe principalmente al exito en la mejora de los metodos de seleccion de los donantes, al igual que al adelanto tecnologico de las pruebas de deteccion e inactivacion de agentes infecciosos en sangre y derivados sanguineos. En este sentido, la implantacion de metodos de deteccion de acidos nucleicos (NAT) para el VIH y el virus de la hepatitis C (VHC) en los bancos de sangre de EE.UU. ha supuesto un avance decisivo a la hora de reducir al minimo el riesgo residual de transmision de estas infecciones a traves de transfusiones sanguineas. El analisis global de los primeros 4 anos de experiencia en el uso de NAT en bancos de sangre de EE.UU. plantea la posibilidad de su implantacion en bancos de sangre europeos, dado el mayor rendimiento alcanzado en la deteccion de infecciones en individuos que se encuentran en estadios muy tempranos de la infeccion, cuando aun no se ha desarrollado una respuesta serologica de anticuerpos.

Seroprevalence of Human T Cell Leukemia Virus in HIV Antibody-Negative Populations in Rural Cameroon

Seven hundred forty-seven serum samples collected from humans in 4 separate rural village areas in Cameroon were examined for antibody to human T cell leukemia viruses (HTLVs) by use of an enzyme immunoassay followed by a Western blot assay. Of the 88 serum samples that the enzyme immunoassay found to be repeatedly reactive, the HTLV status of 49 samples was confirmed by Western blot assay to be HTLV type I, and the status of 6 samples was confirmed to be HTLV type II.