[Identification of Mycobacterium avium-intracellulare complex by PCR of AIDS and disseminated mycobacteriosis]. / Identificación del complejo Mycobacterium avium-intracellulare por PCR en SIDA y micobacteriosis diseminada.

OBJECTIVE: The aim of this study is to differentially identify MAC by PCR in patients with AIDS and disseminated mycobacteriosis. METHODS: A cross sectional study was conducted in Mexico to identify MAC by Molecular Biology. Two sets of primers were synthesized: MAV and MIN, for M. avium and M. intracellulare, respectively. Whole-cell DNAs obtained from 29 clinical isolates and clinical serum specimens from other 24 patients with AIDS and disseminated mycobacterial infection were extracted and amplified by PCR with the MAV and MIN primers. The MAV and MIN primers each amplified one highly specific 1.3-kb segment of the homologous DNA, respectively. RESULTS: Twenty-nine DNAs from MAC clinical isolates identified by Gen-Probe AccuProbes were amplified with the MAV primers. Of the 24 clinical samples, 3 were positive for M. avium and 6 for M. tuberculosis. CONCLUSIONS: Our results demonstrated that PCR technique could be applied for the differentiation of M. avium and M. intracellulare by specific 16S rRNA primers. In patients with advanced stage AIDS and in whom disseminated mycobacteriosis is suspected, the presence of anemia (even with negative cultures), elevated alkaline phosphatase and a median CD4 count of 15.9/mL, the diagnosis of infection by MAC should be strongly considered; we suggest that in accordance with our findings, a more precise stratification of patients in terms of their CD4 T cell counts is warranted.

Introducción: el objetivo de este artículo es Identificar y diferenciar el complejo MAC por PCR en pacientes con SIDA y micobacteriosis diseminada. Métodos: se llevó a cabo un estudio transversal para identificar MAC por biología molecular. Se sintetizaron dos conjuntos de iniciadores: MAV y MIN, para M. avium y M. intracellulare, respectivamente. El ADN total de células obtenidas de 29 aislados clínicos y muestras de suero de otros 24 pacientes con SIDA e infección micobacteriana diseminada fue extraído y se amplificó por PCR con los iniciadores MAV y MIN. Cada uno de los iniciadores MAV y MIN amplificó un segmento altamente específico de 1.3 kb del ADN homólogo, respectivamente. Resultados: veintinueve ADN de los aislados clínicos de MAC identificadas por Gen-Probe AccuProbes se amplificaron con los iniciadores MAV (M. avium). De las 24 muestras clínicas, 3 fueron positivas para M. avium y 6 para M. tuberculosis. Conclusiones: nuestros resultados demostraron que la técnica de PCR se puede aplicar para la diferenciación de M. avium y M. intracellulare por iniciadores específicos 16S rRNA. En pacientes con estadio avanzado de SIDA y en quienes se sospecha micobacteriosis diseminada, la presencia de anemia (incluso con cultivos negativos) fosfatasa alcalina elevada y una mediana de CD4 de 15.9/ml, se debe considerar seriamente el diagnóstico de infección por MAC; sugerimos que, de acuerdo con nuestros resultados, se justifica una estratificación más precisa de los pacientes en términos de sus recuentos de células T CD4.

Microbiología de lavado broncoalveolar en lactantes con neumonía bacteriana adquirida en la comunidad de mala evolución / Microbiology of bronchoalveolar lavage in infants with bacterial community-acquired pneumonia with poor outcome

ResumenIntroducción: La neumonía adquirida en la comunidad (NAC) es una de las causas infecciosas más frecuentes de morbi-mortalidad a escala mundial en niños menores de 5 años. El objetivo del estudio fue precisar el diagnóstico bacteriano etiológico en lactantes con NAC.Métodos: Se condujo un estudio prospectivo, transversal y descriptivo en 17 pacientes de 6 meses a 2 años 11 meses de edad con NAC de mala evolución, que ingresaron al servicio de Neumología pediátrica. A los pacientes se les realizó broncoscopia con lavado broncoalveolar (LBA) con las medidas pertinentes durante el procedimiento para limitar el riesgo de contaminación.Resultados: Las bacterias aerobias aisladas fueron Moraxella sp. (23%), Streptococcus mitis (23%), Streptococcus pneumoniae (18%), Haemophilus influenzae (12%), Streptococcus oralis (12%), y Streptococcus salivarius (12%).Conclusiones: En contraste con otros informes se observó que Moraxella sp. es un importante patógeno potencial bacteriano, posiblemente debido a la mejora en la detección con broncoscopia más LBA.

AbstractBackground: Community-acquired pneumonia (CAP) is one of the most common infectious causes of morbidity and mortality in children <5 years of age. The aim of the study was to clarify the bacterial etiologic diagnosis in infants with CAP.Methods:A prospective, cross-sectional and descriptive study in patients 6 months to 2 years 11 months of age with CAP with poor outcome was conducted. Patients were admitted to the Pediatric Pneumology Service and underwent bronchoscopy with bronchoalveolar lavage (BAL), taking appropriate measures during the procedure to limit the risk of contamination.Results: Aerobic bacteria isolated were Moraxella sp. 23%, Streptococcus mitis 23%, Streptococcus pneumoniae 18%, Haemophilus influenzae 12%, Streptococcus oralis 12%, and Streptococcus salivarius 12%.Conclusions: In contrast to other reports, we found Moraxella sp. to be a major bacterial pathogen, possibly because of improved detection with bronchoscopy plus BAL.

[Microbiology of bronchoalveolar lavage in infants with bacterial community-acquired pneumonia with poor outcome]. / Microbiología de lavado broncoalveolar en lactantes con neumonía bacteriana adquirida en la comunidad de mala evolución.

BACKGROUND: Community-acquired pneumonia (CAP) is one of the most common infectious causes of morbidity and mortality in children <5 years of age. The aim of the study was to clarify the bacterial etiologic diagnosis in infants with CAP. METHODS: A prospective, cross-sectional and descriptive study in patients 6 months to 2 years 11 months of age with CAP with poor outcome was conducted. Patients were admitted to the Pediatric Pneumology Service and underwent bronchoscopy with bronchoalveolar lavage (BAL), taking appropriate measures during the procedure to limit the risk of contamination. RESULTS: Aerobic bacteria isolated were Moraxella sp. 23%, Streptococcus mitis 23%, Streptococcus pneumoniae 18%, Haemophilus influenzae 12%, Streptococcus oralis 12%, and Streptococcus salivarius 12%. CONCLUSIONS: In contrast to other reports, we found Moraxella sp. to be a major bacterial pathogen, possibly because of improved detection with bronchoscopy plus BAL.

[Opportunistic bacteria and microbial flora in children with leukemia and neutropenic enterocolitis]. / Bacterias oportunistas y microbiota en niños con leucemia y enterocolitis neutropénica.

OBJECTIVE: to determine the prevalence of opportunistic microorganisms and microbial flora in neutropenic enterocolitis in oncohematological pediatric patients. METHODS: a prospective and observational study was done. Patients with diagnosis of acute leukemia and neutropenia were included. Stool cultures were taken to identify microorganisms and microbial flora. A χ(2) test with Yates corrections and Fisher exact test were used in the statistical analysis. RESULTS: 21 patients were included (12 male, 57.1 %). The stool cultures showed that 68 % of microorganisms were Gram-negative. The presence of microorganisms Gram-positive was 20 %, 6 % for Candida sp.; 3 % for Cryptosporidium sp.; and in 3 % were acid fast bacilli. Staphylococcus epidermidis, Enterobacter sp., and Escherichia coli were presented in pure culture. No association was found between Gram-positive and Gram-negative microorganisms with age, white cell count or pure or mixed cultures. CONCLUSIONS: although Gram-negative microorganisms were the most frequent, Gram-positive and other microorganisms that are not detected habitually in feces culture were isolated.

Objetivo: determinar la microbiota y la prevalencia de microorganismos oportunistas en niños con leucemia y enterocolitis neutropénica. Métodos: se realizó un estudio prospectivo observacional en pacientes con leucemia aguda y neutropenia. Se tomaron cultivos de heces para identificar la presencia de bacterias y microbiota. Se aplicó estadística descriptiva para su análisis. Resultados: fueron incluidos 21 pacientes (12 hombres, 57.1 %). En 68 % de los coprocultivos se observó desarrollo de microorganismos gramnegativos. La presencia de microorganismos grampositivos fue de 20 %, 6 % de Candida sp., 3 % de Cryptosporidium sp. y en 3 % se observaron bacilos ácido alcohol resistentes. Staphylococcus epidermidis, Enterobacter sp., y Escherichia coli se observaron en cultivo puro. No se encontró asociación entre microorganismos grampositivos y gramnegativos con la edad, el recuento leucocitario ni el cultivo puro o mixto.Conclusiones: aunque los microorganismos gramnegativos fueron los más frecuentes, se aislaron de manera importante grampositivos y otros que no se buscan de rutina en el coprocultivo.

Molecular analysis of mycobacteria isolated in Mexican patients with different immunodeficiencies in a tertiary care hospital.

BACKGROUND AND AIMS: The prevalence of infections with Mycobacterium tuberculosis (MTB) and non-tuberculous mycobacteria (NTM) species in patients with immunodeficiencies in Mexico is unknown. The aim of this study was to identify, at the molecular level, the mycobacterial species most frequently affecting patients with immunodeficiencies and evaluate the genotypic diversity of MTB complex strains. METHODS: We conducted a retrospective study of 97 strains in patients with the diagnosis of pulmonary (all isolates were of pathological significance) or extrapulmonary tuberculosis. PCR analysis was performed to determine whether they belonged to the MTB complex (MTC) or the Mycobacterium avium complex (MAC). Noncharacterized NTM were sequenced and, finally, MTC were genotyped by MIRUs-VNTR and spoligotyping. RESULTS: Of the 97 mycobacterial strains isolated, 53% were M. tuberculosis, 10% M. bovis, 24% M. avium, 9% M. simiae, 2% M. kansasii and 2% M. gordonae. A great genetic diversity was found by MIRU-VNTR with the greatest polymorphism in MIRU 10, 16, 23 and 27. By spoligotyping, the predominant family was T1. Combining both methods, the association of 13 strains in four different groups was found. CONCLUSIONS: This is the first molecular analysis of mycobacteria isolated from patients with immunodeficiencies in Mexico, describing the prevalence of different mycobacterial species in this population. A great genetic diversity of MTB strains was identified. This is also the first report in Mexico describing clinically important isolates of M. simiae.

-592 and -1082 interleukin-10 polymorphisms in pulmonary tuberculosis with type 2 diabetes.

OBJECTIVE: To determine the polymorphisms of Interleukin-10 (IL-10) (-592, -1082) in pulmonary tuberculosis (PTB) with and without type 2 diabetes (T2D). METHODS: We studied a Mexican mestizo population of 37 patients with TB in remission (TBr) and 40 with active pulmonary TB (PTB), 21 patients with TB + T2D, 47 blood donors accepted, and 13 healthy health-care workers with tuberculin skin test positive. Determination of IL-10 polymorphisms was performed by real-time Polymerase chain reaction. RESULTS: IL-10-592C/A presented in a greater proportion in healthy individuals than in patients with type 2 diabetes and TB in a not quite significant statistically manner. IL-10-1082A/A presented more frequently in the group of patients with both diseases, not being statistically significant in comparison with the group of healthy subjects. CONCLUSIONS: This study describes two important new findings. First, it reveals that the IL-10 (-592 A/A and -592 C/C) polymorphisms were found in a greater proportion in a group of patients with T2D and TB than in healthy subjects. Second, the study provides evidence that the (-1082 G/G) polymorphism presented with greater frequency in healthy individuals than in patients with both of these diseases.

Genetic polymorphisms of the tumor necrosis factor and lymphotoxin alpha in type 2 diabetes.

OBJECTIVE: To investigate the frequency of the single-base change polymorphic variants identified in tumor necrosis factor (TNF) gene (-308 G/A) and lymphotoxin alpha (LTA) (+252 G/A) in patients with type 2 diabetes (T2D). METHODS: A prospective study in a Mexican-mestizo population of 51 patients with T2D and 48 healthy subjects was carried out. We took a peripheral blood sample from each individual for identification of the polymorphic genotypes by polymerase chain reaction. RESULTS: The genotype distribution in T2D was: TNF alpha homozygous 0%; TNFG/A heterozygous 20%; TNFG homozygous 80%. CONCLUSIONS: In regards to the TNF -308 G/A genotype, we found a significant difference (p = 0.012) with a bigger frequency in the group of patients. The health controls showed a higher frequency of TNF -308 G/G genotype (p = 0.034).

Interferon γ in patients with HIV/AIDS and suspicion or latent tuberculosis infection.

OBJECTIVE: To assess the usefulness of IGRA test (QuantiFERON(®)-Cell mediated immune) compared with the tuberculin skin test. METHODS: A cross-sectional study was carried out in Mexico, 25 infected patients with HIV-AIDS and the suspicion or with latent tuberculous infection (LTBI) who were >18 years of age and without treatment for tuberculosis (TB), were enrolled in the study. RESULTS: Median cluster of differentiation (CD4) count was 364 cells/µ L and median HIV viral load was 50 copies/mL. Overall, 20 patients (80%) had at least one positive diagnostic test for LTBI: four (16%) had a positive tuberculin skin test and 19 (76%), a positive QuantiFERON(®)-tuberculosis. CONCLUSIONS: No agreement is found between the two diagnostic tests: k = -0.004, 95% confidence interval (-0.2219, 0.2210). Additional longitudinal studies among HIV-infected populations with high prevalence of TB are needed to further assess the usefulness of IGRAs in this patient population.

[Pro-inflammatory cytokines related to severity and mortality in type 2 diabetes patients with soft tissue infection]. / Citocinas, diabetes e infección de tejidos blandos. Su relación con la severidad y mortalidad.

OBJECTIVE: to determine the relation between IL6, IL10 and TNFa serum levels in a cohort of patients with type 2 diabetes (T2D) and severe soft tissue infections (STI), with severity and mortality factors. METHODS: A. comparative and transversal, study with 15 adult patients, any gender, with T2D and STI were done. A T2D control group of 20 patients without STI was included. Apache II Score, glycemia and by ELISA, IL6, IL10 and TNFa, were determined. RESULTS: in all patients, it was a correlation at beginning between glycemia and IL6 (r = 0.67, IC 95 % 0.24-0.88), as soon as glycemia and Apache II, (r = 0.59, IC 95 % 0.11-0.83). CONCLUSIONS: although IL6 was very usefulness, it is not a routine test in clinical laboratory and it is expensive, but in medical practice, it could be possible to evaluate these patients with Apache II Score and glycemia. However, in STI, the values of IL6 and IL10 were highly significant. It is likely that IL6 is a marker of poor outcome.

The usefulness of the buffy coat smear and panbacterial polymerase chain reaction in early diagnosis of neonatal sepsis.

OBJECTIVE: In this study are evaluated the usefulness of the buffy coat smear and panbacterial polymerase chain reaction (PCR) as diagnostic tests in the early detection of neonatal sepsis. MATERIAL AND METHODS: It was studied 49 patients aged up to 28 days who were hospitalized in the Intensive Care Unit (ICUs) of the Neonatology, with a clinical diagnosis of neonatal sepsis and 49 umbilical cord samples of healthy newborns. Blood cultures and 50 microL of plasma were taken for the DNA and performance of the broad-range PCR primer system (panbacterial PCR). Simultaneously, were taken three capillaries with blood for the leukocyte layer (buffy coat) smear, we performed three stains: Gram; Löeffler blue methylene (LBM), and acridine orange (AO). Statistical analysis included sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) against the clinical diagnosis. RESULTS: With respect to stains of buffy coat smear, they resulted very specific, from 90-97%, with 64-75% sensitivity, 87-94% PPV, and 77-82% NPV. In inverse fashion, PCR resulted very sensitive at 96%, with 91% specificity, 92% PPV, and 96% NPV. CONCLUSIONS: Buffy coat smear stains are easy, fast, and specific, while that of PCR was highly sensitive. Thus, both can be utilized as diagnostic tests.

Importancia del diagnóstico molecular en la tuberculosis extrapulmonar / The importance of molecular diagnosis in extrapulmonary tuberculosis

Introducción: La tuberculosis extrapulmonar (TBEP) representa un gran problema diagnóstico, ya que la tinción de Ziehl-Neelsen (ZN) y el cultivo son útiles, pero no pueden detectar un importante número de casos debido a que son poco bacilíferos (paucibacilares). Objetivo: Determinar la utilidad de la reacción en cadena de la polimerasa (PCR) anidada en el diagnóstico de la enfermedad. Material y métodos: De septiembre 2002 a febrero 2008 se estudiaron 469 pacientes con sospecha de TBEP. Se consideró el perfil clínico de los pacientes y se tomaron las muestras biológicas correspondientes. Después de que se procesaron las tinciones de ZN y los cultivos en Lowenstein-Jensen (LJ), se extrajo el DNA y se hizo la PCR anidada. Al final se compararon los resultados de todas las pruebas. Resultados: Se confirmaron 183 pacientes con TBEP, en base a parámetros de laboratorio (ZN, cultivo, PCR positiva), imagenología y respuesta clínica al tratamiento. Conclusión: La PCR puede considerarse como una herramienta valiosa para el diagnóstico de TBEP, a la par con ZN, cultivo, imagenología y respuesta al tratamiento.

Importancia del diagnóstico molecular en la tuberculosis extrapulmonar / The importance of molecular diagnosis in extrapulmonary tuberculosis

Introducción: La tuberculosis extrapulmonar (TBEP) representa un gran problema diagnóstico, ya que la tinción de Ziehl-Neelsen (ZN) y el cultivo son útiles, pero no pueden detectar un importante número de casos debido a que son poco bacilíferos (paucibacilares). Objetivo: Determinar la utilidad de la reacción en cadena de la polimerasa (PCR) anidada en el diagnóstico de la enfermedad. Material y métodos: De septiembre 2002 a febrero 2008 se estudiaron 469 pacientes con sospecha de TBEP. Se consideró el perfil clínico de los pacientes y se tomaron las muestras biológicas correspondientes. Después de que se procesaron las tinciones de ZN y los cultivos en Lowenstein-Jensen (LJ), se extrajo el DNA y se hizo la PCR anidada. Al final se compararon los resultados de todas las pruebas. Resultados: Se confirmaron 183 pacientes con TBEP, en base a parámetros de laboratorio (ZN, cultivo, PCR positiva), imagenología y respuesta clínica al tratamiento. Conclusión: La PCR puede considerarse como una herramienta valiosa para el diagnóstico de TBEP, a la par con ZN, cultivo, imagenología y respuesta al tratamiento. (AU)

[CSF RT-PCR standardization in pediatric patients with enteroviral central nervous system infection]. / Estandarización de RT-PCR en LCR de pacientes pediátricos con infección del sistema nervioso central por enterovirus.

OBJECTIVE: We standardized the RT-PCR panviral CSF and determined its applicability in detecting acute enterovirus infection in the central nervous system in children under 15 years. MATERIAL AND METHODS: RT-PCR was performed directly in CSF samples of 10 pediatric patients with suspected CNS infection and 9, with different conditions of the central nervous system. RESULTS: 80% (8/10) of RT-PCR samples were positive for enterovirus in patients with suspected CNS infection and no sample was positive in patients with different ailments. CONCLUSIONS: Since enteroviruses are among the main etiologies of pediatric encephalitis, RT-PCR could be particularly useful for rapid detection in CSF.

Functional state analysis of phagocytic cells of patients with type 2 diabetes and pulmonary tuberculosis.

BACKGROUND: The phagocytic function in pulmonary tuberculosis (PTB) and Type 2 diabetes (T2D) has been explored mainly in macrophages but not in polymorphonuclears (PMN). The purpose of this study was to determine the functional status of PMN leukocytes in patients with pulmonary tuberculosis (PTB), Type 2 diabetes (T2D), and in patients with both diseases. METHODS: An observational, prospective, and comparative study was carried out. 30 ambulatory patients with T2D, 10 with PTB undergoing treatment and 10 patients with PTB and T2D, and 44 healthy subjects were studied. PMN leukocytes were separated, the capacity of these cells to produce hydrogen peroxide and to reduce nitroblue tetrazolium (NBT) in response to stimulus with the phorbolic ester of myristic acid (PMA) was measured; and the capacity of PMN leukocytes to adhere to surfaces was determined. RESULTS: Concerning the test for adherence, on comparing healthy subjects with patients with T2D+PTB, we observed a clear decrease in cellular adherence in the group of patients with both diseases; it was statistically significant (p = 0.007).With regard to phagocytic function, we observed that in NBT reduction as well as in hydrogen peroxide production, statistically significant differences were not obtained on comparing healthy subjects with any of the three groups of patients. CONCLUSIONS: We observed a clear decrease in cellular adherence when both diseases co-exist. These results could indicate the need for the co-existence of T2D and TB to cause deterioration in the cells' adherence activity. The microtechniques employed permit the evaluation in a practical manner of certain phagocytic-activity expressions.

Tumor necrosis factor -308 and lymphotoxin +252 polymorphisms in Mexican children with Kawasaki disease and coronary aneurysms.

BACKGROUND AND AIMS: The Mexican population has a distinct capacity for the expression of tumor necrosis factor (TNF), a cytokine that plays a cardinal role in Kawasaki disease (KD), particularly in those who develop coronary aneurysms. It is important to identify, in Mexican pediatric patients, the association of the frequency of TNF. This study determined the association of TNF -308 and lymphotoxin-alpha (LTA) +252 polymorphisms in Mexican pediatric patients with KD and coronary aneurysms (CA). METHODS: We conducted a cross-sectional, analytical study in 48 children with KD, 22 with CA. Control samples were obtained from 61 aged-matched children. We took a peripheral blood sample and extracted genomic DNA from all children participating in the study. Using restriction factor length polymorphism-polymerase chain reaction (RFLP-PCR), we performed determination of TNF -308 and LTA +252. RESULTS: There was no difference in frequency between the study groups for genotype LTA +252 (OR 0.37, 95% CI, 0.06-2, p = 0.44) or between groups for KD with or without coronary aneurysms for both polymorphisms. In subjects with KD, we did not observe the heterozygous genotype of TNF -308, the difference being significant (OR 12, 95% CI, 4.8-30.4, p = 0.0001) using the χ(2) test with the continuity correction on comparison with the control group. CONCLUSIONS: Comparative analysis by group did not show a significant difference in the frequency of the alleles and genotypes between KD with CA vs. KD without CA vs. controls, for both TNF -308 and LTA +252.

Polymorphisms in tumor necrosis factor and lymphotoxin A in tuberculosis without and with response to treatment.

This study compared the frequency of the genetic polymorphisms of tumor necrosis factor (TNF) in pulmonary tuberculosis without and with response to treatment. We carried out an observational, prospective, comparative study. Three groups were studied: healthy subjects, responders, and non-responders to directly observed treatment short-course. We took a peripheral blood sample for identification of polymorphic genotypes TNF -308G/A and lymphotoxin A (LTA) +252G/A by polymerase chain reaction, and their later digestion with the Nco1 restriction enzyme. We studied a total of 138 subjects: 42 (non-responders) and 48 in each of the remaining groups. Healthy subjects had significantly high frequency of the LTA +252A allele compared to groups of patients and could be related with protection from the disease. Patients had higher frequency of the non-polymorphic allele LTA +252G than healthy subjects. With regard to LTA +252G/A genotype, we did find a significant difference with a greater frequency in the group of patients. The LTA +252G/A genotype was associated with impaired response to treatment.

Clinical usefulness of the nested polymerase chain reaction in the diagnosis of extrapulmonary tuberculosis.

OBJECTIVE: To evaluate the effectiveness of nested polymerase chain reaction (PCR) for diagnosis of extrapulmonary tuberculosis (ETB), as well as the impact of PCR results on clinical management. MATERIALS AND METHODS: We conducted a study of nested PCR tests in 45 patients and a review of patient hospital files, calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS: PCR was positive in 51% of cases; PCR sensitivity for diagnosing TB was 86%, specificity was 79%, PPV was 76%, and NPV was 88%. When solely analyzing urine samples, sensitivity and NPV increased to 100%. PCR exerted an influence on management in 27% of patients. CONCLUSIONS: PCR for rapid diagnosis of extrapulmonary TB has an adequate effect, which improves when performed on urine. The results of PCR exerted an acceptable impact on the clinical management of these patients.

Clinical usefulness of the nested polymerase chain reaction in the diagnosis of extrapulmonary tuberculosis / Utilidad clínica de la reacción en cadena de la polimerasa anidada para el diagnóstico de tuberculosis extrapulmonar

OBJECTIVE:To evaluate the effectiveness of nested polymerase chain reaction (PCR) for diagnosis of extrapulmonary tuberculosis (ETB), as well as the impact of PCR results on clinical management. MATERIALS AND METHODS:We conducted a study of nested PCR tests in 45 patients and a review of patient hospital files, calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). RESULTS:PCR was positive in 51% of cases; PCR sensitivity for diagnosing TB was 86%, specificity was 79%, PPV was 76%, and NPV was 88%. When solely analyzing urine samples, sensitivity and NPV increased to 100%. PCR exerted an influence on management in 27% of patients. CONCLUSIONS:PCR for rapid diagnosis of extrapulmonary TB has an adequate effect, which improves when performed on urine. The results of PCR exerted an acceptable impact on the clinical management of these patients.

OBJETIVO:Evaluar la eficacia de la reacción en cadena de la polimerasa (PCR) anidada para el diagnóstico de tuberculosis extrapulmonar, así como el impacto de sus resultados en el manejo clínico. MATERIAL Y MÉTODOS: Se realizó PCR anidada en 45 pacientes y se llevó a cabo la revisión de expedientes. Se calculó sensibilidad, especificidad, valor predictivo positivo (VPP) y valor predictivo negativo (VPN). RESULTADOS:La PCR fue positiva en 51% de los casos, la sensibilidad fue de 86%, la especificidad de 79%, el VPP de 76% y el VPN de 88%. Al analizar solamente las muestras de orina, la sensibilidad y VPN se incrementaron a 100%. La PCR influyó en el manejo de 27% de los pacientes. CONCLUSIONES:La PCR para el diagnóstico rápido de TB extrapulmonar tiene una eficacia adecuada, la cual mejora cuando se realiza en orina. El resultado de la PCR tuvo un impacto aceptable en el manejo clínico de estos pacientes.

Detection of Mycobacterium tuberculosis from respiratory samples with the liquid culture system MB/BacT and verified by PCR.

OBJECTIVE: To assess the performance in the clinical setting of the MB/BacT system for isolation of Mycobacterium tuberculosis and to verify by PCR. MATERIAL AND METHODS: The study included 272 sputum samples from 208 patients with the presumptive diagnosis of pulmonary tuberculosis. ZN was made, culture in Löwenstein-Jensen medium, MB/BacT and PCR. RESULTS: Thirty-nine samples were positive by culture in Löwenstein-Jensen, and 42 using the MB/BacT system. Positive cultures in the MB/BacT system were verified by acid-fast bacilli staining and PCR. Mycobacterial identification in the MB/BacT took 8 to 46 days (mean 16 days), while the Löwenstein-Jensen culture ranged between 21 and 63 days (mean 35 days). These results show that the MB/BacT semiautomated system is reliable and faster than the manual culture method and can be used as an alternative for the primary identification of Mycobacterium tuberculosis. The PCR assay allows the fast and exact identification of Mycobacterium tuberculosis directly from positive liquid medium.

[Antibodies against Chlamydophila in patients with acute myocardial infarction and coronary risk and their association with mortality]. / Anticuerpos contra Chlamydophila en pacientes con infarto agudo del miocardio y riesgo coronario, y su relación con la muerte.

OBJECTIVE: The primary aim of this study was to determine whether antibodies against Chlamydophila pneumoniae in patients with acute myocardial infarction (AMI) and coronary risk factors are associated with death. MATERIAL AND METHODS: A cross-sectional study was conducted among 100 patients hospitalized in the Coronary Unit of Centro Medico La Raza Hospital of the Mexican Institute of Social Security, between 1999 and 2000. Subjects were males and females older than 18 years, diagnosed with AMI and coronary risk. Antibodies against Chlamydophila pneumoniae, Chlamydophila psitacii and Chlamydia trachomatis were measured using an indirect microinmunofluorescence assay. In addition, blood samples from 33 patients from the original group were taken when the patients were discharged from the hospital,and 3 months after their myocardial infarction. Data analysis consisted of geometric means and standard deviations as well as odds ratios with 95% confidence intervals. RESULTS: Seventy percent of patients presented antibodies against Chlamydophila pneumoniae. Antibodies against Chlamydophila psittaci and Chlamydia trachomatis were not identified. No statistically significant association was found between antibodies and death in these patients with coronary risk factors and AMI. In the subgroup of 33 individuals 25 had antibodies against Chlamydophila pneumoniae and in 83% of them antibodies decreased three months after the AMI event. CONCLUSIONS: Even though patients with coronary risk factors and AMI had an increased seropositivity for Chlamydophila pneumoniae it was not significantly associated with death.