Evaluación de una prueba de reacción en cadena de la polimerasa múltiplex anidada para la detección de HTLV-1

El Perú es un área endémica al virus linfotrópico T humano tipo 1 (HTLV-1) y para su confirmación diagnóstica se usa pruebas serológicas que pueden dar resultados no concluyentes. Objetivos: evaluar una prueba de PCR múltiplex anidada para diagnosticar el HTLV-1. Métodos: la validación de la PCR se realizó con primers dirigidos a las regiones Pol y LTR del HTLV-1. Se empleó el gen ß-globina como control endógeno interno y el límite de detección se evaluó con células MT2. Los parámetros de precisión diagnóstica se evaluaron frente a 95 muestras sanguíneas de Referencia. Resultados: la prueba evaluada obtuvo un límite de detección de 0,5 ng/µL de ADN sensibilidad diagnóstica=97,1%, especificidad diagnóstica y analítica=100%, vpn=97,2%, vpp, repetibilidad y reproducibilidad=100%; Kappa, Índice Youden=0,97. Conclusiones: la prueba evaluada presenta un alto rendimiento diagnóstico y debido a su bajo costo se recomienda su implementación en el algoritmo del diagnóstico de HTLV-1 en Perú.

Peru is an endemic area for human T-lymphotropic virus type 1 (HTLV-1) and for its diagnostic confirmation serological tests are used, which can give inconclusive results. Objectives: to evaluate a nested multiplex PCR test to diagnose HTLV-1. Methods: PCR validation was performed with primers targeting the Pol and LTR regions of HTLV-1. The ß-globin gene was used as an internal endogenous control and the detection limit was evaluated with MT2 cells. Diagnostic accuracy parameters were evaluated against 95 Reference blood samples. Results: the evaluated test obtained a detection limit of 0.5 ng/µL of DNA; diagnostic sensitivity=97.1%, diagnostic and analytical specificity=100%, vpn=97.2%, vpp, repeatability and reproducibility=100%; Kappa, Youden Index=0.97. Conclusions: the evaluated test has a high diagnostic performance and due to its low cost, its implementation in the HTLV-1 diagnosis algorithm in Peru is recommended.

Ocorrência do vírus da leucemia felina em Felis cattus em Belo Horizonte / Occurrence of feline leukemia virus in Felis cattus in Belo Horizonte

Blood samples from 1,072 domestic cats of nine administrative regions of Belo Horizonte, MG, were collected and tested using PCR nested for the occurrence of feline leukemia virus (FeLV). Overall occurrence was 47.5 percent (507/1072) being North (68.1 percent) and East (54.4 percent) the most prevalent areas. Epidemiological data showed that FeLV infection was very common among examined cats and breed neither gender nor were predisposing factors for FeLV. The results suggest that the agglomeration of a large number of cats in the same environment can be an important factor for the increase in the rate of transmission of this retrovirus among domestic cats in the studied city.

Detecção de Toxoplasma gondii no sêmen de ovinos naturalmente infectados / Toxoplasma gondii detection in the semen of naturally infected sheep

O objetivo deste trabalho foi estudar a eliminação de Toxoplasma gondii no sêmen de carneiros naturalmente infectados. Foram utilizados 65 reprodutores submetidos inicialmente à pesquisa de anticorpos anti-T. gondii por meio da técnica de imunofluorescência indireta (IFI). Os carneiros sorologicamente positivos foram submetidos à colheita de sêmen para detecção do DNA de T. gondii. Na sorologia observaram-se 6/65 (9,2 por cento) carneiros positivos, enquanto no PCR nested de sêmen 4/6 (66,6 por cento) carneiros foram positivos. Conclui-se que a detecção, por meio da técnica da PCR nested, da forma proliferativa de T. gondii no sêmen de carneiros naturalmente infectados, reforça a necessidade de se pesquisar sobre a possibilidade da transmissão horizontal do parasito via sêmen na espécie ovina.

The aim of this paper was to study the Toxoplasma gondii shedding in the semen of naturally infected rams. Sixty-five rams were initially submitted to anti-T. gondii antibody detection by indirect immunofluorescence (IIF). Serologically positive rams were then submitted to semen collection for T. gondii DNA detection. In the serology, 6/65 (9.2 percent) rams were positive, while in the nested PCR of semen there were 4/6 (66.6 percent) positive rams. It can be concluded that detection of the proliferative form of T. gondii in semen of naturally infected rams by the nested PCR technique reinforces the need to investigate possible horizontal transmission of this parasite via semen in sheep.

Avaliação clínica e molecular de cães com erliquiose / Clinical and molecular evaluation of dogs with ehrlichiosis

A erliquiose monocítica canina é uma doença cosmopolita causada por Ehrlichia canis e transmitida pelo carrapato Rhipicephalus sanguineus, sendo frequentemente diagnosticada em cães em todo o Brasil. Este trabalho teve por objetivo investigar citológica e molecularmente a infecção por Ehrlichia em 195 cães atendidos no Hospital Veterinário da Universidade Federal de Mato Grosso, analisando os achados clínicos e laboratoriais. Nos 48 cães atendidos com citologia positiva para Ehrlichia sp., foi possível verificar a diversidade de sinais, com predominância estatisticamente significativa de palidez de mucosas (P≤0,05), assim como variados achados hematológicos, ocorrendo tanto anemia, leucopenia e trombocitopenia, quanto normalidade ou aumento dessas células. Ocorreu aumento das proteínas plasmáticas, com hiperglobulinemia, sem, no entanto, haver diferença significativa (P≥0,05), apesar de esse achado ser frequente nessa afecção. Por meio do PCR nested, confirmou-se a infecção por E. canis em cães da cidade de Cuiabá.

The canine monocytic ehrlichiosis is a cosmopolitan disease, caused by Ehrlichia canis, transmitted by ticks Rhipicephalus sanguineus that has been frequently diagnosed in dogs throughout the country. This study aimed to investigate the cytological and molecular Ehrlichia infection in 195 dogs examined at the University Veterinary Hospital of Mato Grosso, by analyzing the clinical and laboratory findings. In 48 dogs with positive cytology for Ehrlichia sp it was possible to detect the diversity of signs, with predominance statistically significant of pallor of mucous membranes (P≤0.05) as well as several hematological findings, occurring anemia, leukopenia and thrombocytopenia, or increased as normal cells. There was increased of plasma proteins, with hyperglobulinemia, however without any significant difference (P≥0.05), although this finding is common in that infection. Through the nested PCR technique it was possible to confirm the infection by E. canis in the city of Cuiaba.

Identificación de infección oculta por Virus de Hepatitis B en pacientes con insuficiencia renal crónica en Hemodiálisis en Unidad Renal del Hospital Militar Central Bogota Colombia Noviembre 2008

La infección oculta por virus de hepatitis B es una forma reconocida de infección que ha ganado interés en la última década, por su significado clínico y las implicaciones frente a los crecientes estados de inmunosupresión. La hepatitis B oculta corresponde a un estado de infección que no presenta marcadores serológicos como antígeno de superficie de hepatitis b, o elevación de transaminasas; su diagnostico se basa en la presencia de DNA viral en población con o sin anticuerpos contra la partícula del core viral, siendo la población de mayor riesgo, los pacientes con trasplante hepático receptores de donante core +, pacientes con hepatocarcinoma, pacientes con cirrosis criptogénica pacientes con insuficiencia renal crónica, usuarios de drogas intravenosas y donantes de sangre frecuentes. Objetivo: Identificar pacientes con infección oculta por virus de hepatitis B en población con insuficiencia renal crónica en hemodiálisis con mayor riesgo, dados por la presencia de anticuerpo contra partícula core VHB y coinfección con virus de hepatitis C. Materiales y métodos: Pacientes con insuficiencia renal crónica en hemodiálisis en la unidad renal del hospital Militar central. Se describen las características demográficas básicas y se identifican los pacientes con anticuerpo core positivo de manera exclusiva, e infección por virus de hepatitis C. Teniendo en cuenta que esta es la población de mayor riesgo de infección oculta, se realiza cuantificacion del genoma viral por técnica de amplificación. Resultados: La serie corresponde a una población adulta mayor predominantemente masculina, con insuficiencia renal crónica secundaria a nefropatía diabética e hipertensiva en su mayoría; el 54 % de los pacientes vacunados contra hepatitis B presenta anticuerpos protectores, y el 13 % presenta anticuerpo contra partícula core del virus de hepatitis B como marcador exclusivo de enfermedad y un paciente con infección por virus de hepatitis C, sin encontrar la presencia de genoma viral en estos pacientes. Discusión: Los pacientes con insuficiencia renal crónica en hemodiálisis que están expuestos a hemoderivados y procedimientos invasivos; a pesar de las normas de bioseguridad, se encuentran en alto riesgo de infección oculta por virus de hepatitis B. Los estudios multinaciones realizados a nivel mundial muestran una gran variabiliadad en la prevalencia de Hepatitis B oculta, a razón de las características demográficas propias de las poblaciones estudiadas. Conclusiones: No se encontró genoma viral de virus de hepatitis B en pacientes con insuficiencia renal crónica en hemodiálisis mayor de seis meses con anticuerpo contra partícula core positivo exclusivo y coinfección con virus de hepatitis C en la unidad renal del hospital Militar central a noviembre de 2008.

Occult Hepatitis B infection is a very well known form of infection, which has gained attention during the last decade because of its clinical significance and the implications facing immunosuppression conditions. Occult hepatitis B corresponds to an infectious state with the absence of serological hepatitis B markers or transaminase elevation. Its diagnostic is based on viral DNA presence in people who may have or not antibodies against viral coreÊs particle, being the most risky population patients who have had hepatic transplant, receivers of positive core donor, patients with hepatocellular carcinoma, patients with cryptogenic cirrhosis, patients with chronic kidney failure, intravenous drug users and frequent blood donors. This studyÊs objective was to identify patients with occult hepatitis B infection in a population with chronic kidney failure on hemodialysis with higher risk given by the presence of the core particle antibody and co-infection with hepatitis C virus. Materials and methods: the current study takes as target a population of patients with chronic kidney failure in hemodialysis at the kidney unit of the "Hospital Militar Central". A survey which pretends to describe the basic demographic characteristics and to identify patients with exclusive positive core antibody and hepatitis C is applied taking into account that this population is at the highest risk for hidden infection; viral genome identification by the amplification technique was done. Results: the series correspond to a basically adult male population with secondary chronic kidney failure due to diabetic and hypertensive nephropathy; 54% of vaccined patients against hepatitis B had protective antibodies and, 13% presented antibodies against core particle of hepatitis B virus, and one patient was positive to Hepatitis C virus, without the presence of viral genome in this population. Discussion: patients with chronic kidney failure on hemodialysis who are exposed to blood derivatives and invasive procedures in spite of bio - safety policies are at high risk for occult hepatitis B infection. Multinational studies conducted worldwide, show a wide geographical variability in occult hepatitis B prevalence. Conclusions: No hepatitis B viral genome was detected in patients with chronic kidney failure on hemodialysis treatment longer than six months with antibody against core particle and co-infection with hepatitis C virus in the kidney unit of "Hospital Militar Central" by November 2008.