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Elia Palenque

Publications and source records attributed to Elia Palenque.

6 recordsLinked to original sources
PubMed2006

Analysis of changes in recent tuberculosis transmission patterns after a sharp increase in immigration.

We conducted a population-based molecular epidemiological study of tuberculosis (TB) in Madrid, Spain (2002 to 2004), to define transmission patterns and factors associated with clustering. We particularly focused on examining how the increase in TB cases among immigrants in recent years (2.8% in 1997 to 1999 to 36.2% during the current study) was modifying transmission patterns. Mycobacterium tuberculosis isolates obtained from patients living in nine districts of Madrid (1,459,232 inhabitants) were genotyped. The TB case rate among foreign-born people was three to four times that of Spanish-born people, and the median time from arrival to the onset of treatment was 22.4 months. During the study period, 227 (36.3%) patients were grouped in 64 clusters, and 115 (50.7%) of them were in 21 clusters with mixed Spanish-born and foreign-born patients. Three of the 21 mixed clusters accounted for 21.1% of clustered patients. Twenty-two of 38 (57.9%) immigrants in mixed clusters were infected with TB strains that had already been identified in the native population in 1997 to 1999, including the three most prevalent strains. Factors identified as independent predictors of clustering were homelessness (odds ratio [OR], 2.3; 95% confidence interval [95% CI], 1.2 to 4.5; P = 0.011) and to be born in Spain (OR, 1.8; 95% CI, 1.2 to 2.6; P = 0.002). The results indicated that (i) TB transmission was higher in Spanish-born people, associated mainly with homelessness, (ii) that foreign-born people were much less likely to be clustered, suggesting a higher percentage of infection before arriving in Spain, and (iii) that an extensive transmission between Spanish- and foreign-born populations, caused mainly by autochthonous strains, was taking place in Madrid.

Adolescent↗
PubMed2006

Interferon gamma quantification in cerebrospinal fluid compared with PCR for the diagnosis of tuberculous meningitis.

PURPOSE: To assess the utility of interferon gamma (INF-gamma) levels in cerebrospinal fluid (CSF), for the diagnosis of tuberculous meningitis (TBM), and compare these results with aPCR technique. METHODS: We studied CSF samples from patients with proven or probable TBM and a control group, composed by patients with other causes of meningitis and without meningitis. INFgamma levels were measured by radioimmunoassay. A PCR technique was performed using IS6110 primers. RESULTS: Of the 127 patients studied, 20 (15.6%) had TBM, 59 (46%) had meningitis of another aetiology and 49 (38.4%) had were HIV and non-HIV patients with normal CSF. The area below the ROC curve for interferon gamma levels in the diagnosis of TBM was 0.94. A cut-off of 6.4 IU/mL yielded a sensitivity of 70% and a specificity of 94%. False positive results were observed in 7 of the 59 patients (11.8%) with non-TB meningitis, (patients with herpetic meningoencephalitis and meningitis due to intracellular microorganisms). INF-gamma sensitivity was higher than PCR (70% vs. 65%). Both tests performed together showed higher sensitivity (80%) and specificity (92.6%). CONCLUSION: CSF INF-gamma levels (> 6.4 IU/mL) are very valuable in TBM diagnosis. PCR and INF-gamma could be simultaneously used to increase the diagnostic yield.

Adolescent↗
PubMed2006

Blood and urine samples as useful sources for the direct detection of tuberculosis by polymerase chain reaction.

The aim of the study was to assess the utility of the polymerase chain reaction (PCR) assay in blood and urine for the diagnosis of tuberculosis (TB). We prospectively evaluated the usefulness of PCR performed in blood and urine samples from patients with proved or probable TB compared with a control group of patients. The PCR technique was performed using IS6110 primers. We included in the study 57 patients (43 with definite TB and 14 with probable TB) and 26 controls. Blood and urine samples were drawn at the time of microbiologic diagnosis and 3, 6, 9, and 12 months later. Cultures were positive in the early period (<1 month after treatment) in 11 of 57 patients (19%) with probable or definite TB, in comparison with 42% of patients (24/57) who yielded a positive PCR (P = 0.02). Urine samples increased the sensitivity of PCR determination in blood samples by 10%. The PCR in blood and/or urine was positive in 41% of patients with pulmonary TB, in 36% of patients with extrapulmonary TB, and in 50% of patients with disseminated TB. Mycobacterium tuberculosis was still detectable by PCR in 5 of 13 patients with cured TB after 1 or more months of antituberculous treatment. The PCR detection of M. tuberculosis in blood and urine samples is useful for the diagnosis of different clinical forms of TB, mostly in those patients in which sample extraction is difficult or requires aggressive techniques. The sensitivity of this technique could be improved studying more than 1 sample in each patient, even after initiating an antituberculous treatment.

Antitubercular Agents↗
PubMed2006

Mycobacterium colombiense sp. nov., a novel member of the Mycobacterium avium complex and description of MAC-X as a new ITS genetic variant.

Forty-five mycobacterial strains isolated from 23 Colombian HIV-positive patients were identified as members of the Mycobacterium avium complex (MAC) and were characterized using different molecular approaches. Seven of the isolates showed characteristic features that allowed them to be differentiated from other members of the complex. The isolates had a novel 16S-23S rRNA internal transcribed spacer (ITS 1) gene sequence which is described as a new sequevar, MAC-X. All of the seven novel isolates gave a positive result with the MAC-specific AccuProbe (Gen-Probe), but tested negative for Mycobacterium avium and Mycobacterium intracellulare species-specific probes (64 and 100 % of the isolates, respectively). The novel isolates could be differentiated phenotypically from other members of the MAC on the basis of the production of urease and by a consistent mycolic acid pattern. The novel isolates shared some characteristics with M. avium, such as the avium variant I (av-I) pattern of the hsp65 gene as determined by PCR restriction analysis and a positive PCR result for the mig (macrophage-induced) gene. However, the novel isolates showed a unique 16S rRNA gene sequence. DNA-DNA relatedness values, from 24 to 44 %, confirmed the distinction of the novel isolates from other members of the MAC at the genetic level and their status as members of a separate species. The novel isolates are proposed as representatives of a novel species, Mycobacterium colombiense sp. nov., that is closely related to M. avium within the MAC. The type strain is 10B(T) (=CIP 108962(T)=CECT 3035(T)).

Bacterial Typing Techniques↗
PubMed2004

[Distribution of PRA patterns of clinical isolates of the Mycobacterium avium complex from Spain and South America].

Mycobacterium avium complex (MAC) infections are the most frequent systemic infections associated with advanced AIDS. DNA probes for accurate identification of mycobacteria are available but are very expensive in many Latin American settings. Consequently, most Latin American diagnostic laboratories employ inaccurate and outdated tests for mycobacteria identification. Therefore, PCR restriction analysis (PRA) of the hsp65 gene was evaluated for the identification of 163 MAC human isolates originated from Spain and South America. The predominant PRA type in each country was: M. avium type I in Argentina (23/42, 55%) and Brazil (48/72, 67%), M. avium type II in Spain (18/26, 69%) and M. avium type III in Colombia (10/23, 43%). The Colombia frequency is noteworthy, since the PRA type III was quite infrequent in the other three countries. Furthermore, its presence has not been reported outside the Americas. The advantages and disadvantages of PRA in diagnostic mycobacteriology are discussed.

Humans↗