Microbiological assessment of arterial allografts processed in a tissue bank.

The transmission of microbial infection through tissue allografts is one of the main risks that must be controlled in tissue banks. Therefore, microbiological monitoring controls and validated protocols for the decontamination of tissues during processing have been implemented. This study is based on the evaluation of data from microbiological cultures of arteries (mainly long peripheral arteries) processed in the tissue bank of Valencia (Spain). Donors' profile, pre- and post-disinfection tissue samples were assessed. The presence of residual antibiotics in disinfected tissues was determined and the antimicrobial potential of these tissues was tested. Our overall contamination rate was 23.69%, with a disinfection rate (after antibiotic incubation) of 87.5%. Most (76.09%) of the microbial contaminants were identified as Gram positive. Arterial allografts collected from body sites affected by prior organ removal showed higher risk of contamination. Only vancomycin was detected as tissue release. The antimicrobial effect on Candida albicans was lower than that for bacterial species. Risk assessment for microbial contamination suggested the donor's skin and the environment during tissue collection as the main sources for allograft contamination. Antibiotic-disinfected arterial allografts showed antimicrobial potential.

[Evaluation of galactomannan antigen and Aspergillus real time PCR for diagnosis of invasive aspergillosis]. / Evaluación del antígeno galactomanano y la PCR en tiempo real de Aspergillus para el diagnóstico de aspergilosis invasiva.

INTRODUCTION: The aim of the study was to compare the galactomannan antigen (GA) and molecular biology (PCRrt) tests with the culture in the diagnosis of invasive aspergillosis (IA). MATERIAL AND METHODS: Four hundred and seventy two samples were analyzed: 388 respiratory and 84 serum samples from 271 patients. Culture and GA were evaluated in the respiratory samples and GA in the serum samples. PCR was used when discrepancies were observed among culture and GA tests. RESULTS: The detection of GA in serum was positive in 22 (of 84), 21 had the test positive respiratory sample. Of the 62 sera with negative GA, 45 were also negative respiratory specimens. The culture was positive in 37 of which were positive for GA. Comparing culture with AG, it showed PPV=23%, NPV=100%, S=100% and E=52%. The PCR showed respect to culture: PPV=69%, NPV=89%, S=64% and E=82%. In sera were found in 60% discrepancies between PCRrt and GA. CONCLUSIONS: We consider useful the GA detection in serum combined with culture and GA in respiratory samples, for diagnosis of AI. PCR requires further studies for standardization and set breakpoints.

A seroepidemiological study of human immunodeficiency virus infection in northeast Zaire.

To evaluate the incidence of human immunodeficiency virus type 2 infections in an endemic African area, we have studied 134 patients from Northeast Zaire. Sera were tested for HIV-1 and HIV-2 antibodies to asses cross-reactivity or a possible double infection. Sixty five (48.5%) serum samples were reactive for HIV-1 and six (4.5%) for HIV-2 using specific Western blots. The enzyme immunoassays used to detect HIV-2 showed cross-reactivity with HIV-1 in 17 samples (16.5%). Tests based upon synthetic peptides corresponding to specific from human immunodeficiency viruses confirm their ability to discriminate antibodies directed against both viruses in 42/47 samples (89.4%); in 5/47 (10.6%) this test could not distinguish double infection from cross-reactivity. We suggest that the high number of sexual partners may be responsible for HIV transmission in our study group.

PIP: To evaluate the incidence of human immunodeficiency virus type 2 infections in an endemic African area, the authors have studied 134 patients from Northeast Zaire. Sera were tested for HIV-1 and HIV-2 antibodies to assess cross-reactivity or a possible double infection. 65 (48.5%) serum samples were reactive for HIV-1 and 6 (4.5%) for HIV-2 using specific Western blots. The enzyme immunoassay used to detect HIV-2 showed cross-reactivity with HIV-1 in 17 samples (16.5%). Tests based upon synthetic peptides corresponding to specific glycopeptides from human immunodeficiency viruses confirm their ability to discriminate antibodies directed against both viruses in 42/47 samples (89.4%); in 5/47 (10.6%) this test could not distinguish double infection from cross-reactivity. The authors suggest that the high number of sexual partners may be responsible for HIV transmission in this study group. (author's)

[Use of DNA amplification to diagnose cytomegalovirus in HIV seropositive patients]. / Utilidad de la amplificación de DNA para diagnosticar citomegalovirus en la población seropositiva para el virus de la inmunodeficiencia humana.

BACKGROUND: Cytomegalovirus (CMV) infection is common among HIV seropositive patients, being difficult to diagnose because it requires cell cultures not available in all hospitals. DNA amplification is being applied for diagnosis of infectious diseases with an increase in sensitivity and specificity with respect to previous laboratory methods. METHODS: Polymerase chain reaction (PCR) has been used in comparison with culture isolation, early antigen detection to diagnose CMV infection in 22 HIV infected patients, that suffered from symptoms compatible with CMV infection at the present time, and in other 5 patients suffering from Kaposi sarcoma. PCR was done with primer for CMV IE genomic region. The amplified sequences were detected after hybridization with a gamma-P-32 labelled probe, followed by electrophoresis in a 5% polyacrylamide gel and autoradiography. RESULTS: The PCR allows to detect CMV genome in cases in which other tests are negatives, in blood as well as in urine, included those patients suffering only from febrile symptoms or with other associated pathogen. CONCLUSIONS: PCR is a sensitive method to detect CMV, although it does not establish the responsibility of CMV in HIV infected patients.