Optimization of genotypic and biochemical methods to profile P. acnes isolates from a patient population.

Propionibacterium acnes is a key factor in the pathogenesis of acne vulgaris, although currently it is also being associated with medical-device infections. The aim of this work was to validate a safe and quick identification and typing of 24 clinical isolates of Propionibacterium acnes, applying a range of biochemical as well as genetic methods, and investigating the pathogenic potential to associate the different types with human health. RAPD-PCRs revealed the existence of two discernible clusters in correspondence with the phylogroups I and II, according to the PAtig gene polymorphism, leading them to be assigned as P. acnes subsp. acnes subsp. nov. Biotyping according to the pattern of sugar fermentation evidenced that all the isolates from acne and the majority from opportunistic infections fit the biotype I-B3. Consistent with the multiplex touchdown analysis, nearly all the isolates included in this biotype belonged to the subgroups IA1 (the exception being four strains classified as IB). The remaining ones were assigned to phylogroup II, considered to be part of the normal cutaneous microbiota. The susceptibility to three antibiotics was also investigated to explore the relations with the virulence, although no clear trend was identified.

Comparative Study of a Real-Time PCR Assay Targeting senX3-regX3 versus Other Molecular Strategies Commonly Used in the Diagnosis of Tuberculosis.

BACKGROUND: Nucleic acid amplification tests are increasingly used for the rapid diagnosis of tuberculosis. We undertook a comparative study of the efficiency and diagnostic yield of a real-time PCR senX3-regX3 based assay versus the classical IS6110 target and the new commercial methods. METHODS: This single-blind prospective comparative study included 145 consecutive samples: 76 from patients with culture-confirmed tuberculosis (86.8% pulmonary and 13.2% extrapulmonary tuberculosis: 48.7% smear-positive and 51.3% smear-negative) and 69 control samples (24 from patients diagnosed with non-tuberculous mycobacteria infections and 45 from patients with suspected tuberculosis which was eventually ruled out). All samples were tested by two CE-marked assays (Xpert®MTB/RIF and AnyplexTM plus MTB/NTM) and two in-house assays targeting senX3-regX3 and the IS6110 gene. RESULTS: The detection limit ranged from 1.00E+01 fg for Anyplex, senX3-regX3 and IS6110 to 1.00E+04 fg for Xpert. All three Xpert, senX3-regX3 and IS6110 assays detected all 37 smear-positive cases. Conversely, Anyplex was positive in 34 (91.9%) smear-positive cases. In patients with smear-negative tuberculosis, differences were observed between the assays; Xpert detected 22 (56.41%) of the 39 smear-negative samples, Anyplex 24 (61.53%), senX3-regX3 28 (71.79%) and IS6110 35 (89.74%). Xpert and senX3-regX3 were negative in all control samples; however, the false positive rate was 8.7% and 13% for Anyplex and IS6110, respectively. The overall sensitivity was 77.6%, 85.7%, 77.3% and 94.7% and the specificity was 100%, 100%, 90.8% and 87.0% for the Xpert, senX3-regX3, Anyplex and IS6110 assays, respectively. CONCLUSION: Real-time PCR assays targeting IS6110 lack the desired specificity. The Xpert MTB/RIF and in-house senX3-regX3 assays are both sensitive and specific for the detection of MTBC in both pulmonary and extrapulmonary samples. Therefore, the real time PCR senX3-regX3 based assay could be a useful and complementary tool in the diagnosis of tuberculosis.

Factors associated with unreported tuberculosis cases in Spanish hospitals.

BACKGROUND: Under-reporting of tuberculosis (TB) cases complicates disease control, hinders contact tracing and alters the accuracy of epidemiological data, including disease burden. The objective of the present study is to evaluate the proportion of unreported TB cases in Spanish healthcare facilities and to identify the associated factors. METHODS: A multi-center retrospective study design was employed. The study included TB cases diagnosed in 16 facilities during 2011-2012. These cases were compared to those reported to the corresponding public health departments. Demographic, microbiological and clinical data were analyzed to determine the factors associated with unreported cases. Associated factors were analyzed on a bivariate level using the x(2) test and on a multivariate level using a logistic regression. Odds ratios (OR) and 95 % confidence intervals (CI) were calculated. RESULTS: Of the 592 TB cases included in the study, 85 (14.4 %) were not reported. The percentage of unreported cases per healthcare center ranged from 0-45.2 %. The following variables were associated to under-reporting at a multivariate level: smear-negative TB (OR = 1.87; CI:1.07-3.28), extrapulmonary disease (OR = 2.07; CI:1.05-4.09) and retired patients (OR = 3.04; CI:1.29-7.18). A nurse case manager was present in all of the centers with 100 % reporting. The percentage of reported cases among the smear-positive cases was 9.4 % and 19.4 % (p = 0.001) among the rest of the study population. Smear-positive TB was no associated to under-reporting. CONCLUSIONS: It is important that TB Control Programs encourage thorough case reporting to improve disease control, contact tracing and accuracy of epidemiological data. The help from a TB nurse case manager could improve the rate of under-reporting.

Comparative clinical study of different multiplex real time PCR strategies for the simultaneous differential diagnosis between extrapulmonary tuberculosis and focal complications of brucellosis.

BACKGROUND: Both brucellosis and tuberculosis are chronic-debilitating systemic granulomatous diseases with a high incidence in many countries in Africa, Central and South America, the Middle East and the Indian subcontinent. Certain focal complications of brucellosis and extrapulmonary tuberculosis are very difficult to differentiate clinically, biologically and radiologically. As the conventional microbiological methods for the diagnosis of the two diseases have many limitations, as well as being time-consuming, multiplex real time PCR (M RT-PCR) could be a promising and practical approach to hasten the differential diagnosis and improve prognosis. METHODOLOGY/PRINCIPAL FINDINGS: We designed a SYBR Green single-tube multiplex real-time PCR protocol targeting bcsp31 and the IS711 sequence detecting all pathogenic species and biovars of Brucella genus, the IS6110 sequence detecting Mycobacterium genus, and the intergenic region senX3-regX3 specifically detecting Mycobacterium tuberculosis complex. The diagnostic yield of the M RT-PCR with the three pairs of resultant amplicons was then analyzed in 91 clinical samples corresponding to 30 patients with focal complications of brucellosis, 24 patients with extrapulmonary tuberculosis, and 36 patients (Control Group) with different infectious, autoimmune or neoplastic diseases. Thirty-five patients had vertebral osteomyelitis, 21 subacute or chronic meningitis or meningoencephalitis, 13 liver or splenic abscess, eight orchiepididymitis, seven subacute or chronic arthritis, and the remaining seven samples were from different locations. Of the three pairs of amplicons (senX3-regX3+ bcsp3, senX3-regX3+ IS711 and IS6110+ IS711) only senX3-regX3+ IS711 was 100% specific for both the Brucella genus and M. tuberculosis complex. For all the clinical samples studied, the overall sensitivity, specificity, and positive and negative predictive values of the M RT-PCR assay were 89.1%, 100%, 85.7% and 100%, respectively, with an accuracy of 93.4%, (95% CI, 88.3-96.5%). CONCLUSIONS/SIGNIFICANCE: In this study, a M RT-PCR strategy with species-specific primers based on senX3-regX3+IS711 sequences proved to be a sensitive and specific test, useful for the highly efficient detection of M. tuberculosis and Brucella spp in very different clinical samples. It thus represents an advance in the differential diagnosis between some forms of extrapulmonary tuberculosis and focal complications of brucellosis.

Amplicon DNA melting analysis for the simultaneous detection of Brucella spp and Mycobacterium tuberculosis complex. Potential use in rapid differential diagnosis between extrapulmonary tuberculosis and focal complications of brucellosis.

Some sites of extrapulmonary tuberculosis and focal complications of brucellosis are very difficult to differentiate clinically, radiologically, and even histopathologically. Conventional microbiological methods for the diagnosis of extrapulmonary tuberculosis and complicated brucellosis not only lack adequate sensitivity, they are also time consuming, which could lead to an unfavourable prognosis. The aim of this work was to develop a multiplex real-time PCR assay based on SYBR Green I to simultaneously detect Brucella spp and Mycobacterium tuberculosis complex and evaluate the efficacy of the technique with different candidate genes. The IS711, bcsp31 and omp2a genes were used for the identification of Brucella spp and the IS6110, senX3-regX3 and cfp31 genes were targeted for the detection of the M. tuberculosis complex. As a result of the different combinations of primers, nine different reactions were evaluated. A test was defined as positive only when the gene combinations were capable of co-amplifying both pathogens in a single reaction tube and showed distinguishable melting temperatures for each microorganism. According to the melting analysis, only three combinations of amplicons (senX3-regX3+bcsp31, senX3-regX3+IS711 and IS6110+IS711) were visible. Detection limits of senX3-regX3+bcsp31 and senX3-regX3+IS711 were of 2 and 3 genome equivalents for M. tuberculosis complex and Brucella while for IS6110+IS711 they were of 200 and 300 genome equivalents, respectively. The three assays correctly identified all the samples, showing negative results for the control patients. The presence of multicopy elements and GC content were the components most influencing the efficiency of the test; this should be taken into account when designing a multiplex-based SYBR Green I assay. In conclusion, multiplex real time PCR assays based on the targets senX3-regX3+bcsp31 and senX3-regX3+IS711 using SYBR Green I are highly sensitive and reproducible. This may therefore be a practical approach for the rapid differential diagnosis between extrapulmonary tuberculosis and complicated brucellosis.

Multiplex real-time polymerase chain reaction: a practical approach for rapid diagnosis of tuberculous and brucellar vertebral osteomyelitis.

STUDY DESIGN: Case-control study for assessing a diagnostic test. OBJECTIVE: The aim of this study was to analyze the diagnostic yield of a multiplex real-time polymerase chain reaction (PCR) assay in the differential diagnosis of tuberculous vertebral osteomyelitis (TVO) and brucellar vertebral osteomyelitis (BVO). SUMMARY OF BACKGROUND DATA: Vertebral osteomyelitis (VO) is one of commonest osteoarticular complications of tuberculosis and brucellosis. However, the very similar clinical, radiologic, and histologic characteristics of these entities mean that diagnosis requires etiological confirmation, but conventional microbiologic methods have important limitations. METHODS: Fifteen vertebral samples from patients with TVO or BVO and 9 from pyogenic and nontuberculous mycobacteria VO were studied by multiplex PCR and conventional microbiologic techniques. To identify Brucella DNA, we used a fragment of 207 bp from the conserved region of the gene coding for an immunogenic membrane protein of 31 kDa of B. abortus (BCSP31) and for Mycobacterium tuberculosis complex, a fragment of 164 bp from the intergenic region SenX3-RegX3. RESULTS: The histopathologic findings were inconclusive in 4 of 14 cases (28.6%) with TVO or BVO and cultures were positive in 11 of 15 cases (73.3%). Multiplex PCR correctly identified 14 of the 15 samples from patients with TVO and BVO and was negative in all the control samples. Thus, the overall sensitivity and specificity of the multiplex PCR were 93.3% and 90%, respectively, with an accuracy of 92% (95% CI, 81.4%-100%). CONCLUSION: These results suggest that multiplex real-time PCR is far more sensitive than conventional cultures, and this, together with its speed, makes this technique a very practical approach for the differential diagnosis between TVO and BVO.

Rapid differential diagnosis between extrapulmonary tuberculosis and focal complications of brucellosis using a multiplex real-time PCR assay.

BACKGROUND: Arduous to differ clinically, extrapulmonary tuberculosis and focal complications of brucellosis remain important causes of morbidity and mortality in many countries. We developed and applied a multiplex real-time PCR assay (M RT-PCR) for the simultaneous detection of Mycobacterium tuberculosis complex and Brucella spp. METHODOLOGY: Conventional microbiological techniques and M RT-PCR for M. tuberculosis complex and Brucella spp were performed on 45 clinical specimens from patients with focal complications of brucellosis or extrapulmonary tuberculosis and 26 control samples. Fragments of 207 bp and 164 bp from the conserved region of the genes coding for an immunogenic membrane protein of 31 kDa of B. abortus (BCSP31) and the intergenic region SenX3-RegX3 were used for the identification of Brucella and M. tuberculosis complex, respectively. CONCLUSIONS: The detection limit of the M RT-PCR was 2 genomes per reaction for both pathogens and the intra- and inter-assay coefficients of variation were 0.44% and 0.93% for Brucella and 0.58% and 1.12% for Mycobacterium. M RT-PCR correctly identified 42 of the 45 samples from patients with tuberculosis or brucellosis and was negative in all the controls. Thus, the overall sensitivity, specificity, PPV and NPV values of the M RT PCR assay were 93.3%, 100%, 100% and 89.7%, respectively, with an accuracy of 95.8% (95% CI, 91.1%-100%). Since M RT-PCR is highly reproducible and more rapid and sensitive than conventional microbiological tests, this technique could be a promising and practical approach for the differential diagnosis between extrapulmonary tuberculosis and focal complications of brucellosis.

Orquiepididimitis por Mycobacterium africanum / No disponible

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Clinical findings, therapeutic approach, and outcome of brucellar vertebral osteomyelitis.

BACKGROUND: Osteoarticular complications are the most common focal complications of brucellosis. Although vertebral osteomyelitis is the most frequent location in adults >30 years of age, little information is available about this serious complication of brucellosis, and great confusion surrounds its prognosis and the most appropriate treatment. METHODS: We undertook a descriptive, retrospective, observational study of 96 patients who received a diagnosis of brucella vertebral osteomyelitis from September 1982 through December 2005 at a tertiary care hospital. All of the patients were treated for 3 months, after which they were followed up monthly for the first 3 months and then at 2-month intervals for the subsequent 6 months. RESULTS: The incidence of vertebral osteomyelitis was 10.4%. The mean diagnostic delay was 12.7 weeks. Inflammatory spinal pain (occurring in 94.8% of patients) and fever (91.7%) were the most relevant clinical characteristics. Eight patients (8.3%) had motor weakness or paralysis. Paravertebral masses, epidural masses, and psoas abscesses were detected in 45.8%, 27.1%, and 10.4% of patients, respectively. Sixty-three patients (65.6%) received medication only, and 33 (34.4%) required surgical therapy in addition to medication. Twenty percent of patients experienced therapeutic failure. Attributable mortality was 2.1%, and severe functional sequelae were apparent in 6.2% of the patients. No significant differences were seen between patients who were treated with doxycycline-streptomycin and those treated with doxycycline-rifampicin. CONCLUSIONS: Vertebral osteomyelitis is a serious complication of brucellosis. It generates a high rate of therapeutic failure and functional sequelae. In the absence of more-powerful controlled studies, the duration of treatment of brucellar vertebral osteomyelitis should be 3 months.

Clinical findings, diagnostic approach, and outcome of Brucella melitensis epididymo-orchitis.

We have studied 912 patients with brucellosis. Of these, 631 (69.2%) were male and 48 had epididymo-orchitis, giving an incidence of epididymo-orchitis of 7.6%. The duration of symptoms before diagnosis was 52.5 +/- 70 days. All the patients had fever, swelling, and scrotal pain, but only 2 (4.2%) reported urinary symptoms. Seven patients (14.5%) had leukocyte figures above 11 x 10(9)/L, and urine analysis was normal in 69% of the patients. Blood cultures were positive in 65.8% of cases. A total of 33 patients (68.8%) received a combination of doxycycline plus streptomycin and 13 (27.1%) doxycycline plus rifampin. The overall percentage of failure or relapse was 8.8%: 7.1% in the doxycycline plus streptomycin group and 20% in the doxycycline plus rifampin group. None of the patients required surgery. Pending clinical trials to confirm the results, conservative management with a combination of doxycycline for 2 months and streptomycin for 14 to 21 days appears to be adequate and could avoid unnecessary orchiectomy.

Disfunción endotelial y desequilibrio hemostásico en el síndrome X cardiológico / Endothelial dysfunction and hemostatic imbalance in cardiological syndrome X

Introducción: La posible existencia de disfunción endotelial y desequilibrio hemostásico en síndrome X cardiológico, frecuente en la posmenopausia, es un tema controvertido. Objetivo: Comparar los biomarcadores: factor de Von Willebrand (FvW), fibrinógeno (Fb), inhibidor del factor tisular total (TFPI-t) y del activador del plasminógeno (PAI-1) en pacientes sin enfermedad arterial coronaria (síndrome X cardiológico, angina mixta y angina vasoespástica) y pacientes con enfermedad arterial coronaria. Material y métodos: Se determinaron estos biomarcadores en 10 pacientes con síndrome X cardiológico, en 13 con angina mixta, en 15 con angina vasoespástica, en 10 con enfermedad arterial coronaria y en 20 controles sanos. Resultados: Respecto del control sano, todas las pacientes presentaron valores elevados de Fb (3,1 g/l [2,7-3,6] frente a 2,8 g/l [2,2-3,2]; p - 0,03), FvW (211,9% [165-266] frente a 116,5% [91-155]; p < 0,001), TFPI-t (122,3 ng/ml [101-136] frente a 86 ng/ml [72-100]; p < 0,001) y PAI-1 (45,9 ng/ml [32-61] frente a 21 [11-26] ng/ml; p < 0,001). Sin embargo, los pacientes sin enfermedad arterial coronaria respecto de los pacientes con enfermedad arterial coronaria presentaron niveles menores de FvW (200,5% [151-249] frente a 255,2% [221-277]; p - 0,01) y TFPI-t (110,5 ng/ml [100-127] frente a 136,7 [121-148] ng/ml; p - 0,02]. Conclusión: Los pacientes con síndrome X cardiológico presentan una situación de disfunción endotelial y de desequilibrio hemostásico similar a aquellos con angina mixta o angina vasoespástica, aunque menos severo que en pacientes con enfermedad arterial coronaria

Introduction: The possible presence of endothelial dysfunction and hemostatic imbalance in cardiological syndrome X, frequent in the postmenopause, remains controversial. Objective: To compare the biomarkers von Willebrand factor (vWF), fibrinogen (Fb), total tissue factor pathway inhibitor (TFPI-t) and plasminogen activator inhibitor (PAI-1) between patients without coronary artery disease (cardiological syndrome X, mixed angina and vasospastic angina) and patients with coronary artery disease. Material and methods: These biomarkers were determined in 10 patients with cardiological syndrome X, 13 patients with mixed angina, 15 patients with vasospastic angina, 10 patients with coronary arterial disease and 20 healthy controls. Results: Compared with healthy controls, all patients had elevated levels of Fb [3.1 (2.7-3.6) vs 2.8 (2.2-3.2) g/l; P -.003], vWF [211.9 (165-266) vs 116.5 (91-155)%, TFPI-t [122.3 (101-136) vs 86 (72-100) ng/ml; P<.001] and PAI-1 [45.9 (32-61) vs 21 (11-26) ng/ml; P<.001]. However, patients without coronary artery disease had lower levels of vWF [200.5 (151-249) vs 255.2 (221-277) %; P -.01)] and TFPI-t [110.5 (100-127) vs 136.7 (121-148) ng/ml; P -.02)] than those with coronary artery disease. Conclusion: The presence of endothelial dysfunction and hemostatic imbalance is similar in patients with cardiological syndrome X and those with mixed or vasospastic angina, although these disorders are less severe than in patients with coronary artery disease

Peritonitis plástica miliar y fístula estercorácea / Miliary plastic peritonitis and stercoraceous fistula

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Lesiones forunculoides en espalda y pierna / Furunculoid lesions on the back and leg

No disponible

Evaluation of Cobas Integra 800 under simulated routine conditions in six laboratories.

The new selective access analyser Cobas Integra 800 from Roche Diagnostics was evaluated in an international multicentre study at six sites. Routine simulation experiments showed good performance and full functionality of the instrument and provocation of anomalous situations generated no problems. The new features on Cobas Integra 800, namely clot detection and dispensing control, worked according to specifications. The imprecision of Cobas Integra 800 fulfilled the proposed quality specifications regarding imprecision of analytical systems for clinical chemistry with few exceptions. Claims for linearity, drift, and carry-over were all within the defined specifications, except urea linearity. Interference exists in some cases, as could be expected due to the chemistries applied. Accuracy met the proposed quality specifications, except in some special cases. Method comparisons with Cobas Integra 700 showed good agreement; comparisons with other analysis systems yielded in several cases explicable deviations. Practicability of Cobas Integra 800 met or exceeded the requirements for more than 95% of all attributes rated. The strong points of the new analysis system were reagent handling, long stability of calibration curves, high number of tests on board, compatibility of the sample carrier to other Roche systems, and the sample integrity check for more reliable analytical results. The improvement of the workflow offered by the 5-position rack and STAT handling like on Cobas Integra 800 makes the instrument attractive for further consolidation in the medium-sized laboratory, for dedicated use of special analytes, and/or as back-up in the large routine laboratory.

Infección diseminada por Mycobacterium celatum / Disseminated infection due to mycobaterium celatum

No disponible