Linfadenitis por mycobacterium incluyendo pacientes infectados por el virus de inmunodeficiencia humana / Mycobacterium lymphadenitis including patients infected with human inmunodefi

El género Mycobacterium provoca infecciones pulmonares y extrapulmonares, de estas últimas predomina la infección ganglionar. Mientras Mycobacterium tuberculosis es el agente causal más importante, en las últimas décadas aumenta la incidencia de otras especies micobacterianas que se han hecho prevalentes en los pacientes positivos al virus de la inmunodeficiencia humana (VIH +) tanto en países desarrollados como en vías de desarrollo. Durante el período enero 2007 hasta diciembre 2009 se procesó en nuestro laboratorio 6540 muestras, 210 muestras fueron obtenidas por biopsia ganglionar, precisamente este constituyó nuestro universo de estudio, 190 (90.4%) muestras se obtuvieron por exéresis quirúrgica, 20 (9.5%) por punción espirativa;17 procedían de pacientes VIH– (8.1%) y 193 procedentes de pacientes VIH+(91.9%). En solo 16 muestras (7.6%) el cultivo BAAR fue positivo; 4 procedentes de pacientes VIH– (25%) y 12 VIH+(75%). La clasificación e identificación micobacteriana demostró la presencia de Mycobacterium tuberculosis en 13 de los casos (81.25%), mientras Mycobacterium avium-intracellulare fue aislado en 3 (18.7%). En los pacientes inmunodeprimidos con linfadenopatía incluidos los pacientes VIH/sida, es muy importante la búsqueda activa de la presencia de BAAR como coinfección oportunista, donde Mycobacterium tuberculosis se mantiene como el agente infeccioso más frecuente, sin embargo la posibilidad de que otras especies micobacterianas también estén presentes no se debe descartar. Nuestro objetivo en este estudio como Laboratorio Nacional de Referencia de TB- Micobacterias fue lograr la caracterización etiológica de linfadenopatías en pacientes en que se sospechaba clínicamente la participación del género Mycobacterium.

Mycobacterium tuberculosis is the most important etiological agent producing pulmonary as well as extrapulmonary infection. During these last decades, the increase in the incidence of infection due to other mycobacteria species is evident. Lymphadenopathy is the most frequent extrapulmonary presentation form of Mycobacterium Genera infection among HIV positive patients either in developed or underdeveloped countries. The aim of this work is to analyze the results obtained during January 2007 - December 2009 in our laboratory. Two hundred ten tissue samples were studied; 190 (90.4%) samples were lymph node biopsied tissues and 20 (9.5%) samples were obtained by fine needle aspiration; 17 were from HIV - patients (8.1%) and 193 from HIV + (91.9%). A total of 16 (7.6%) samples produced a positive culture for BAAR, 4 VIH- (25%) and 12 VIH+ (75%). Classification and identification for mycobacteria confirmed Mycobacterium tuberculosis in 13 of the cases (81.25%), and Mycobacterium avium-intracellulare in three patients (18.7%). The present study once again confirms that BAAR culture has more sensitivity and specificity than histopathologhic studies have. Lymphadenopathy in immunosuppressed patients should by studied for the presence of an BAAR coinfection where M. tuberculosis is still the agent most frequently found, nevertheless, other species of Mycobacteria may be causing infection and should be searched for. Our objective as National Reference Laboratory of Tuberculosis and Mycobacterial was to obtain the etiological characterization of Mycobacterium lymphadenopathy in clinically suspect patients.

Lipids of 'Mycobacterium habana', a synonym of Mycobacterium simiae with vaccine potential.

'Mycobacterium habana' was proposed as a distinct species within the genus Mycobacterium; however, it is actually a synonym of Mycobacterium simiae and included in the serotype I of this species. The potential use of 'M. habana' as a vaccine in both leprosy and tuberculosis has led to the analysis of its lipid composition in an attempt to define distinctive markers that could be used in the quality control of true strains of this bacterium. Lipids of taxonomic value (fatty and mycolic acids) are similar in 'M. habana' and M. simiae; nevertheless, they clearly differ on the basis of glycopeptidolipid (GPL) composition. Thus, contrary to M. simiae, most strains of 'M. habana' can be defined by the presence of three polar compounds, designated GPL-I, GPL-II and GPL-III, easily determined by thin-layer chromatography, and characterized, respectively, by the content of l-fucose, 2,4-di-O-Me-d-glucuronic acid, and 4-O-Me-d-glucuronic acid, as epitopes.

[A chromatographic analysis of the Mycobacterium tuberculosis strains isolated from an outbreak in HIV patients in Cuba]. / Análisis cromatográfico de cepas de Mycobacterium tuberculosis aisladas de un brote en pacientes VIH en Cuba.

A group of strains of Mycobacterium tuberculosis isolated from an outbreak in HIV-infected patients was studied by chromatographic techniques. A group of strains of M. Tuberculosis from symptomatic respiratory patients (SR+ 14) and patterns strains from the laboratory collection were used as a reference aimed at making a qualitative comparison of the chromatographic patterns described by the strains isolated from patients. The chromatographic profiles of the strains isolated from patients (SR+) and fro HIV+ were obtained and compared by thin layer chromatography (TLC). Each of the present fatty acids was identified by using the gas chromatography technique (GC) coupled to mass spectrum analysis. All the studied strains were classified as Mycobacterium tuberculosis. According to the results attained, the usefulness of the chromatographic techniques as alternative techniques for the mycobacterial diagnosis is demonstrated.