Avaliação de dois testes sorológicos comerciais para diagnóstico das infecções pelo FIV e pelo FeLV / Evaluation of two point-of-care tests to diagnosis of FIV and FeLV infections

FIV e FeLV são retrovírus associados principalmente com neoplasias. Dois testes rápidos são disponibilizados no Brasil para o diagnóstico dessas infecções: um kit de imunocromatografia de fluxo bidirecional (SNAP® Combo IDEXX) e um kit de imunocromatografia de fluxo lateral unidirecional (ALERE/BIONOTE Anigen Rapid). O objetivo deste estudo foi comparar o teste SNAP® com o teste ALERE. Amostras de sangue de 178 gatos foram testadas utilizando-se ambos os kits. A reação em cadeia de polimerase em tempo real (qPCR) foi empregada como método confirmatório para todos os resultados. O teste SNAP® apresentou sensibilidade e especificidade de 100% para FIV; a sensibilidade e a especificidade do teste ALERE foram de 96,15% e 98,68%, respectivamente. A sensibilidade e a especificidade para o FeLV foram de 93,02% e 96,30% para o teste SNAP® e de 90,70% e 97,78% para o teste ALERE. Ainda em relação ao FeLV, três amostras com resultado positivo na qPCR obtiveram resultado falso-negativo em ambos os testes. Não houve diferença estatisticamente significante entre os métodos. Considerando a qPCR como padrão-ouro, o teste SNAP® apresentou maior sensibilidade e especificidade para o FIV, e o teste ALERE apresentou maior especificidade para o FeLV. Os resultados mostraram uma boa correlação entre os testes.(AU)

FIV and FeLV are Retrovirus associated mainly with feline neoplasms. Two point-of-care tests are commercially available in Brazil for diagnosis of these infections: a bidirectional flow immunochromatography kit (IDEXX SNAP ® Combo) and a lateral unidirectional flow immunochromatography kit (ALERE/BIONOTE Anigen Rapid). The aim of this study was to compare SNAP ® and ALERE tests. Blood samples obtained from 178 cats were evaluated using both tests. Quantitative real-time polymerase chain reaction (qPCR) was used as confirmatory test for all samples. The sensitivity and specificity of SNAP ® test was 100% for FIV, and for ALERE test was 96.15% and 98.68%, respectively. The sensitivity and specificity for FeLV was 93.02% and 96.30% for SNAP ® test and 90.70% and 97.78% for ALERE test. Three samples with a qPCR positive result for FeLV obtained a false negative result in both SNAP ® and ALERE tests. There was no statistically significant difference between the two methods. Considering qPCR as gold standard method, the SNAP® test showed higher sensitivity and specificity for FIV, and the ALERE test presented higher specificity for FeLV. The results showed good agreement among the tests.(AU)

Tuberculosis and HIV infection among female inmates in São Paulo, Brazil: a prospective cohort study.

Prison populations are at increased risk of both human immunodeficiency virus (HIV) and Mycobacterium tuberculosis infections, but among female inmates information on such risks remains scarce, especially in developing countries. Between October 1992 and November 1993, 350 women incarcerated at a prison in São Paulo, Brazil, were prospectively evaluated for HIV and M. tuberculosis infection and disease. Among them, 87 (25%) were HIV seropositive, and 20 (5.7%) had tuberculosis (TB). During the incarceration period, the purified protein derivative test conversion rate was 29% for HIV-positive and 32% for HIV-negative women. However, the incidence of TB was 9.9 per 100 person-years for HIV-positive and 0.7 per 100 person-years of incarceration for HIV-negative women (p < 0.0001). A multivariate analysis indicated that HIV infection (p < 0.0001) and incarceration time < 12 months (p < 0.05) were each associated with TB. These findings indicate that new transmissions of M. tuberculosis infection are common among female inmates and that HIV-infected women are more likely to acquire active disease during the first 12 months of incarceration. Because of their role in childbearing and care female inmates are an important potential source of transmission of M. tuberculosis, and new strategies to control the spread of TB in prisons need to be developed.

Seroprevalence of HIV, HTLV-I/II and other perinatally-transmitted pathogens in Salvador, Bahia.

Generation of epidemiological data on perinatally-transmitted infections is a fundamental tool for the formulation of health policies. In Brazil, this information is scarce, particularly in Northeast, the poorest region of the country. In order to gain some insights of the problem we studied the seroprevalence of some perinatally-transmitted infections in 1,024 low income pregnant women in Salvador, Bahia. The prevalences were as follow: HIV-1 (0.10%), HTLV-I/II (0.88%), T.cruzi (2.34%). T.pallidum (3.91%), rubella virus (77.44%). T.gondii IgM (2.87%) and IgG (69.34%), HBs Ag (0.6%) and anti-HBs (7.62%). Rubella virus and T.gondii IgG antibodies were present in more than two thirds of pregnant women but antibodies against other pathogens were present at much lower rates. We found that the prevalence of HTLV-I/II was nine times higher than that found for HIV-1. In some cases such as T.cruzi and hepatitis B infection there was a decrease in the prevalence over the years. On the other hand, there was an increase in the seroprevalence of T.gondii infection. Our data strongly recommend mandatory screening tests for HTLV-I/II, T.gondii (IgM), T.pallidum and rubella virus in prenatal routine for pregnant women in Salvador. Screening test for T.cruzi, hepatitis and HIV-1 is recommended whenever risk factors associated with these infections are suspected. However in areas with high prevalence for these infections, the mandatory screening test in prenatal care should be considered.

Human T-lymphotropic virus type I and type II infections and correlation with risk factors in blood donors from São Paulo, Brazil.

BACKGROUND: Little is known about the prevalence of and risk factors for human T-lymphotropic virus type I and type II (HTLV-I, HTLV-II) infections in Brazil. STUDY DESIGN AND METHODS: Sera from 17,063 healthy Brazilian donors were screened by enzyme-linked immunosorbent assay for antibody to HTLV-I/II between August 1991 and July 1993. Repeatedly reactive samples were confirmed by Western blot, and discrimination between HTLV-I and HTLV-II was made by polymerase chain reaction or synthetic peptide enzyme-linked immunosorbent assay. A univariate analysis was performed on demographic and serologic data. RESULTS: HTLV-I infection was demonstrated in 83 percent of the 30 donors with reactive serologic tests (0.15% of the total tested [17,063]; 95% CI, 0.09-0.20) and HTLV-II infection in 17 percent (0.03% of the total tested [17,063]; 95% CI, 0.01-0.05). HTLV-I-positive donors were more likely than reference groups to be of Asian ethnicity (odds ratio [OR] 15.1; reference group: whites), more than 50 years old (OR 4.2; reference group: 20-29 years old), and positive for antibody to hepatitis C virus (anti-HCV) (OR 21.8) or to hepatitis B core (antigen) (anti-HBc) (OR 5.7). HTLV-II showed a significant association with anti-HCV (OR 75.2) and anti-HBc (OR 21.8). Eleven of the 25 HTLV-I-positive donors were counseled. Family origin in endemic areas of Japan (n = 4), prior blood transfusion (n = 3), or sexual contact with prostitutes (n = 1) were the risk factors reported by 8 donors. In 3 white men, no risk factors could be identified. CONCLUSION: Both HTLV-I and HTLV-II occur among Brazilian blood donors. HTLV-I is associated with Asian ethnicity, greater age, and the presence of anti-HCV and anti-HBc. Three HTLV-I-positive donors had a history of blood transfusion, which emphasizes the need for HTLV-I/II screening in Brazil.

Alpha 4 beta 1 recognition of the Hep II domain of fibronectin is constitutive on some hemopoietic cells but requires activation on others [corrected].

Leukocyte adhesion to the carboxyl-terminal region of fibronectin, a major component of extracellular matrices, involves recognition of the CS-1 site and the Hep II domain. We have previously shown that cultured T and B lymphoid cells constitutively attach via the alpha 4 beta 1 integrin to a 38-kDa fibronectin fragment that contains CS-1 and Hep II, and to a 58-kDa fragment that contains Hep II only. In this report we have studied the adhesion of other hemopoietic cells to the CS-1 and Hep II regions of fibronectin. Cultured monocytic cells and peripheral blood T lymphocytes constitutively bound to the 38-kDa fragment indicating that alpha 4 beta 1 was functional. These cells, however, were unable to bind to the 58-kDa fragment. On lymphoid cells both fragments were shown to bind to very close regions of alpha 4 beta 1 as indicated by the inhibition pattern of mAb to various alpha 4 epitopes, and by the good inhibitory capacity of soluble 38-kDa fragment on cell adhesion to 58-kDa fragment. These results suggested that alpha 4 beta 1 is present on certain cell populations as a partially active form able to recognize the "high affinity" ligand CS-1 but not the "low affinity" ligand Hep II. Binding of monocytic cells and peripheral blood T lymphocytes to the Hep II domain could be induced by several agents: first, long (48-h) and short (20-min) treatment with phorbol esters; second, cell incubation with the divalent cation Mn2+; third, and most effective, cell incubation with the mAb TS2/16, which is directed to the beta 1 integrin subunit. Binding to the 58-kDa fragment in all three cases was completely inhibited by mAb anti-alpha 4, thus confirming the involvement of alpha 4 beta 1 in the recognition of the Hep II domain. No major changes on alpha 4 beta 1 surface expression were observed after these treatments as determined by immunofluorescence analyses. Our results indicate that hemopoietic cells may differentially bind the CS-1 and Hep II ligands in fibronectin depending on the activation state of alpha 4 beta 1, a fact that may be relevant for the migration and function of leukocytes.

Migracao leucocitaria "in vivo" em pacientes submetidos a dialise peritoneal periodica. / \"In vivo leucocyte migration in patients under chronic peritoneal dialysis

Analisou-se o conteudo celular dialitica drenada da cavidade peritoneal, durante dialise peritoneal, em cinco pacientes com insuficiencia renal cronica. As celulas obtidas mostraram sempre viabilidade maior que 90%, e foram analisadas pelo metodo de Giemsa e metodos citoquimicos para esterase acida e mieloperoxidase. No inicio do procedimento dialitico, observou-se um pico celular composto basicamente por fagocitos mononucleares, linfocitos e eosinofilos. Em tres dos cincos pacientes, apos grande reducao do numero de celulas drenadas da cavidade peritoneal, observou-se um segundo pico celular composto principalmente por neutrofilos, com desaparecimento de outros tipos celulares. Este segundo pico celular nao foi observado em outros dois pacientes, o que sugere a existencia de diferentes padroes de migracao leucocitaria para cavidade peritoneal