Laboratory features for presumptive diagnosis of disseminated tuberculosis in HIV-infected patients.

Rapid diagnosis is crucial for adequate treatment of disseminated mycobacteriosis. We conducted a retrospective cohort study to identify clinical and laboratorial features of disseminated mycobacteriosis in human immunodeficiency virus (HIV) infected patients that could help to differentiate tuberculosis (TB) from non-tuberculous mycobacteria (NTM) disease. All patients diagnosed from 1996 to 2006 were reviewed. TB was diagnosed in 65 patients and NTM in 31. Patients with TB had higher median levels of aspartate aminotransferase (AST) (69.0 vs. 45.0, P = 0.02) and lactate dehydrogenase (LDH) (725.0 vs. 569.0, P = 0.03). AST and LDH may be valuable tools in differentiating disseminated TB from NTM in HIV-infected patients.

Isolation and identification of mycobacteria in New World primates maintained in captivity.

The presence of several Mycobacterium species was determined in 68 New World monkeys kept captive in the Cali Zoo. One hundred and thirty-three gastric lavage and blood samples were evaluated for mycobacterial presence by Ziehl-Neelsen (ZN) staining, culture and PCR amplification of the Mycobacterium tuberculosis Mtp40 species-specific gene. Mycobacteria other than tuberculosis (MOTT) were identified by PCR restriction fragment length polymorphism (RFLP). Different species of mycobacteria were detected in 65% of the primate population studied by Alpha Antigen PCR. Eleven percent were positive for Mtp40 PCR amplification, being diagnosed as having M. tuberculosis, and acid-fast bacilli were observed in 23% by ZN staining. MOTT were isolated from samples taken from 37 primates by culturing; according to the RFLP analysis, three strains were classified as belonging to the MAISS complex (Mycobacterium avium-intracellulare-scrofulaceum-simiae) and eight more, isolated from soil inside the cages, were categorized as environmental contaminants. Mycobacterium spp. were detected in 13 different New World primate species showing that PCR amplification of the Mtp40 gene is a better tool than culture for M. tuberculosis detection in captive animals and that RFLP is a useful technique for MOTT identification.

Hemocultivos convencionales para Mycobacterium spp. en enfermos con SIDA / Conventional hemocultures for Mycobacterium spp. in AIDS patients

El diagnóstico de las mycobacteriosis diseminadas en enfermos con sida se realiza eficazmente mediante la realización de hemocultivos. Los mismos no se realizan en laboratorios clínicos por su alto costo y complejidad. Desarrollamos y evaluamos un sistema de hemocultivos convencionales de bajo costo y fácil ejecución para el aislamiento de mycobacterias en sangre. Las muestras de sangre recogidas con polianetol sulfonato de sodio como anticoagulante se inocularon en frascos de medio 7H9+OADC. Se realizaron repiques en medio de Lowenstein Jensen inmediatamente a la inoculación y a los 14 y 28 días posteriores. Los resultados obtenidos son similares a los obtenidos con el sistema Isolator 10, con porcentajes de positividad de 9,5 por ciento en muestras y de 12,5 por ciento en enfermos. La demora promedio para el informe de positivos fue de 30 días. El aislamiento más frecuente fue Mycobacterium avium complex(AU)

Systemic mycobacterioses in AIDS patients as determined by blood cultures on biphasic medium.

Bacteremia due to mycobacteria can occur in AIDS patients in whom a rapid diagnosis is extremely important in order to plan a therapeutic conduct. Blood culture of mycobacteria using a biphasic system was set up in the Regional Laboratories of the Adolfo Lutz Institute, SP (Campinas, Ribeirão Preto, Santo André, Santos, São José do Rio Preto and Sorocaba). During a three year period (1994-97), 1521 blood samples were analyzed from 1336 AIDS patients, with CD4+ cell count < 100/ml, hematocrit < 30% and serum albumin concentration < 3.0 g/dl seen in regional outpatient clinics or as inpatients in hospitals. Of the blood samples examined, 9.9% were positive for mycobacteria. The predominant species was Mycobacterium avium complex (MAC) (53.8%) followed by Mycobacterium tuberculosis (28.0%). Mycobacterium xenopi was isolated in one case (0.8%) and in the remaining 17.4% the mycobacteria isolated were not identified. The implementation of blood culture for mycobacteria in our Institute has permitted the laboratory diagnosis of mycobacterial infections, in addition to providing data on the frequency of disseminated mycobacterial disease in AIDS patients in the region.

Systemic mycobacterioses in AIDS patients as determined by blood cultures on biphasic medium

Bacteremia due to mycobacteria can occur in AIDS patients in whom a rapid diagnosis is extremely important in order to plan a therapeutic conduct. Blood culture of mycobacteria using a biphasic system was set up in the Regional Laboratories of the Adolfo Lutz Institute, SP (Campinas, RibeirOo Preto, Santo AndrU, Santos, SOo JosU do Rio Preto and Sorocaba). During a three year period (1994-97), 1521 blood samples were analyzed from 1336 AIDS patients, with CD4+ cell count < 100/ml, hematocrit < 30 and serum albumin concentration < 3.0 g/dl seen in regional outpatient clinics or as inpatients in hospitals. Of the blood samples examined, 9.9 were positive for mycobacteria. The predominant species was Mycobacterium avium complex (MAC) (53.8) followed by Mycobacterium tuberculosis (28.0). Mycobacterium xenopi was isolated in one case (0.8) and in the remaining 17.4 the mycobacteria isolated were not identified. The implementation of blood culture for mycobacteria in our Institute has permitted the laboratory diagnosis of mycobacterial infections, in addition to providing data on the frequency of disseminated mycobacterial disease in AIDS patients in the region.(AU)

Hemocultivos: clasificación, indicaciones e interpretación de sus resultados en el diagnóstico de bacteremia / Blood cultures: classification, indications and interpretation of its results in the diagnosis of bacteremia

La septicemia es una de las principales causas de muerte entre pacientes hospitalizados. El aislamiento del agente causal de la bacteremia a través de los hemocultivos constituye una herramienta de gran utilidad en el proceso diagnóstico. Los hemocultivos pueden ser clasificados según la obtención de la muestra (catéter venoso central, vena periférico), según el tipo de microorganismo (bacterias aerobias, anaerobias o fastidiosas, hongos, micobacterias, virus) o según el sistema utilizado (manual, automatizado). Los nuevos métodos de hemocultivos han permitido ampliar el espectro de microorganismos identificados. Para obtener resultados confiables es necesario que la obtención de la muestra sea adecuada en cuanto al volumen de sangre obtenido, número de hemocultivos, desinfección de la piel y al momento de obtención (comienzo del episodio febril). Para diferenciar entre bacteremia verdadera y colonización se debe considerar el cuadro clínico, el tipo de microorganismo aislado y el número de hemocultivos positivos. La interpretación de un hemocultivo positivo se basa en una adecuada evaluación clínica y en el uso apropiado de las metodologías disponibles

Recognition of lipid antigens by sera of mice infected with Mycobacterium lepraemurium.

Lipids extracted from mouse tissues infected with Mycobacterium lepraemurium (MLM) were analyzed by thin-layer chromatography. Although the extracted lipids were heterogeneous in polarity, the lipids of intermediate polarity were the ones that predominated. All of the lipids of intermediate polarity were glycosylated species. There were also lipids of low and high polarity, the latter being glycolipids. Compared to lipids extracted from normal tissue (mostly to lipids of high and low polarity), all of the additional lipids extracted from the infected tissue corresponded to lipids present in the purified bacteria. Enzyme-linked immunoassays (ELISAs) were then performed with the whole lipids extracted from purified bacilli, the lipids of high, intermediate and low polarity, and the sera from 20 normal and 20 MLM-infected mice. Lipids of intermediate polarity were specifically recognized by MLM-infected mice. Neither sera (diluted 1:500) from normal mice nor infected mice reacted with the lipids of high or low polarity, but a higher concentration (sera diluted 1:100) of some sera from mice in both groups reacted significantly with these lipids. In the ELISAs the whole-lipid extract and the lipids of intermediate polarity were similarly recognized by the sera of the infected mice. Thus, as observed in human leprosy, the mycobacterial disease in the mouse (murine leprosy) is also accompanied by the development of antibodies to the glycolipids of the infecting microorganism.