Mycobacterium avium infection in Portugal

BACKGROUND

Although the incidence rates of non-tuberculous mycobacteria (NTM) have been increasing in many countries, the basic epidemiology of NTM remains to be fully understood.

OBJECTIVE

To assess the incidence, clinical relevance and geographical distribution of NTM disease in Portugal and to identify demographic and clinical characteristics associated with Mycobacterium avium complex (MAC) disease.

METHODS

Information stored in an electronic database of all NTM cases reported over an 11-year period was retrospectively reviewed. Significant demographic and clinical characteristics of MAC disease (vs. having any other NTM disease) were determined using multiple logistic regression models.

RESULTS

We identified 632 patients, mostly male, native Portuguese, with pulmonary disease, predominantly from Lisbon and Porto. The annual incidence of NTM disease was 0.54 per 100 000 population. The annual number of NTM cases increased throughout the study period. MAC was most frequently isolated. MAC disease was positively (and significantly) associated with being female, age >45 years and human immunodeficiency virus infection.

CONCLUSIONS

The increasing incidence of NTM over the study period emphasises the importance of NTM as a public health issue. This study provides important information for health care professionals and a basis for further study of NTM in Portugal.

Longitudinal clustering of tuberculosis incidence and predictors for the time profiles: the impact of HIV

BACKGROUND

Portugal remains the country with the highest tuberculosis (TB) incidence in Western Europe.

OBJECTIVES

To identify longitudinal trends in TB incidence in Portugal from 2002 to 2012 and investigate the longitudinal effect of sociodemographic and health-related predictors among the resident population on the TB incidence rate.

METHODS

We used data from the National Tuberculosis Surveillance System and other national institutions. K-means longitudinal clustering algorithm was performed on TB incidence time profiles from districts of Portugal.

RESULTS

Three longitudinal profiles for the TB incidence rate of Portugal were identified. In all of them, TB incidence decreased over time. Among all studied sociodemographic and health-related predictors, human immunodeficiency virus (HIV) notification rate and unemployment were shown to have (positive) significant effects on TB incidence. In particular, the greatest effects were found for the HIV notification rate.

CONCLUSIONS

Our study supports the view that combined TB-HIV strategies and the improvement of social determinants can contribute to decreases in TB incidence.

Nosocomial tuberculosis prevention in Portuguese hospitals: a cross-sectional evaluation

SETTING

Measures to control tuberculous infection are crucial to prevent nosocomial transmission and protect health care workers (HCWs). In Portugal, the extent of implementation of tuberculosis (TB) control measures in hospitals is not known.

OBJECTIVE

To determine the current implementation of preventive measures for tuberculous infection at administrative, environmental and personal levels in Portuguese hospitals.

DESIGN

A cross-sectional evaluation was performed using two anonymous questionnaires: one sent to all the hospital infection control (IC) committees and the other sent to all pulmonologists and physicians specialising in infectious disease.

RESULTS

Fourteen IC committees and 72 physicians responded. According to the IC committees, 92% of hospitals had a written TB control plan, but only 37% of the physicians said there was always/almost always a fast track for diagnosing suspected pulmonary TB cases. The majority of the hospitals had an isolation policy (85%) and these patients were always/almost always admitted in separate rooms, according to 70% of physicians. Both HCWs and TB patients used respiratory protection equipment (92%).

CONCLUSION

These findings indicate that the most basic TB IC measures had been undertaken, but some TB IC measures were not fully implemented at all hospitals. An institutional effort should be made to solve this problem and strengthen TB prevention activities.

In vitro cytotoxicity evaluation of resveratrol-loaded nanoparticles: Focus on the challenges of in vitro methodologies

Assessment of toxic effects is mandatory before market placement of pharmaceutical and cosmetic products. Nanotoxicology is an emerging regulatory concern and still a challenging field. Topical application of resveratrol (RSV) has been extensively studied owing to its multi-mechanistic skin anti-aging effects. Nanoencapsulation has been suggested as a promising solution to overcome RSV stability issues. In this work RSV-loaded solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) were prepared using a homogenization/sonication technique. Cytotoxicity assays were conducted with an immortalized cell line of human keratinocytes (HaCaT). For a comprehensive cytotoxicity characterization MTT and Alamar Blue^® reduction assays (assessment of metabolic activity), Neutral red uptake (evaluation of lysosomal integrity), and Trypan blue (assessment of membrane integrity) were used. The results obtained with the different assays were not always concordant, as put in evidence by an adequate statistical analysis. Experimental parameters such as washing steps were found to be critical. The study is of interest because it draws attention to the importance of careful selected experimental conditions of in vitro nanotoxicological tests. Experimental protocols should be adapted taking into account nano-related features such as interference with the dyes and light dispersion/absorption properties.

Tuberculosis in native- and foreign-born populations in Portugal

BACKGROUND

Tuberculosis (TB) is a major global health problem, and during the last 20 years, industrialised countries have shown similar patterns in TB notifications: decreasing TB incidence in native populations and increasing incidence in foreign-born populations.

OBJECTIVES

To characterise risk factors associated with TB among native- and foreign-born TB patients in Portugal and identify barriers to the management of foreign cases.

METHODS

Analysis of the data from the national tuberculosis surveillance system and data from an online survey of physicians managing TB cases in the country.

RESULTS

Risk factors in the two populations differed. Foreign-born patients were younger, less likely to use drugs or alcohol and had fewer comorbidities. They were also more likely to be human immunodeficiency virus positive, to be employed and to be homeless/living in shelters. The outcome of the disease and the time to diagnosis were not significantly different between the two populations. The most important barriers to the management of foreign-born TB cases were language and fear of deportation.

CONCLUSIONS

As there are significant differences between the two populations, different TB control strategies should be implemented in the two populations.

Tuberculosis screening in patients receiving biological therapy

AIM

Biological therapies are a risk factor for tuberculosis (TB). Portuguese recommendations recommend universal baseline screening for TB before starting biologics (2006) and annually thereafter if screened negative (2012 update). The gain with re-screening remains unknown. We aimed to i)identify the risk of latent TB infection at baseline screening among patients candidates to initiate biologics ii)present follow-up results for patients receiving different biological therapies and analyse intolerance or toxicity related to preventive therapy, conversions of immunodiagnostic tests under biological therapy and development of active TB.

METHODS

Patients screened for TB at a reference centre before starting biological therapy between 2008-2012 were identified. Medical files were retrospectively reviewed. Demographic data, screening and follow-up results and information on biological therapy were collected.

EXCLUSION CRITERIA

unavailable information on initiation of biological therapy.

RESULTS

183 patients were included in the study, with 115 starting biological therapy. The baseline screening was positive in 52(45,2%) patients - 50(96,2%) were proposed for preventive treatment (2 had abnormal liver enzymes). Mild hepatotoxicity occurred in 4(8%) patients without need to interrupt TB prophylaxis. No cases of active TB occurred during follow-up in patients with positive baseline screening. Among the 63(54,8%) patients who screened negative, 2(3,2%) developed active TB (under infliximab and adalimumab) more than one year after initiation of biologics. 26(41,3%) patients were re-screened at the TB centre. 5(19,2%) had tuberculin skin test (TST) conversion and one concomitantly undetermined IGRA. No IGRA conversions were observed. The follow-up period was 4,0 years. TB baseline screening's negative predictive value (NPV) was 96,8% (95%CI: 89,0% to 99.5%). A low rate of re-screening was observed.

CONCLUSION

The rate of latent TB at baseline screening was higher than expected. Preventive treatment was well tolerated. No patients with positive baseline screening developed active TB. Efforts should be made to raise awareness concerning the risk of TB exposure, specially considering that the active TB cases were compatible with new infection. The rate of re-screening suggests a low awareness regarding current recommendations Nation-wide studies are necessary to evaluate the efficacy of the re-screening strategy and to clarify what risk groups most benefit from it.

Fetal-maternal interface impedance parallels local NADPH oxidase related superoxide production

Blood flow assessment employing Doppler techniques is a useful procedure in pregnancy evaluation, as it may predict pregnancy disorders coursing with increased uterine vascular impedance, as pre-eclampsia. While the local causes are unknown, emphasis has been put on reactive oxygen species (ROS) excessive production. As NADPH oxidase (NOX) is a ROS generator, it is hypothesized that combining Doppler assessment with NOX activity might provide useful knowledge on placental bed disorders underlying mechanisms. A prospective longitudinal study was performed in 19 normal course, singleton pregnancies. Fetal aortic isthmus (AoI) and maternal uterine arteries (UtA) pulsatility index (PI) were recorded at two time points: 20-22 and 40-41 weeks, just before elective Cesarean section. In addition, placenta and placental bed biopsies were performed immediately after fetal extraction. NOX activity was evaluated using a dihydroethidium-based fluorescence method and associations to PI values were studied with Spearman correlations. A clustering of pregnancies coursing with higher and lower PI values was shown, which correlated strongly with placental bed NOX activity, but less consistently with placental tissue. The study provides evidence favoring that placental bed NOX activity parallels UtA PI enhancement and suggests that an excess in oxidation underlies the development of pregnancy disorders coursing with enhanced UtA impedance.

Pneumococcal pneumonia - Are the new severity scores more accurate in predicting adverse outcomes?

INTRODUCTION

The site-of-care decision is one of the most important factors in the management of patients with community-acquired pneumonia. The severity scores are validated prognostic tools for community-acquired pneumonia mortality and treatment site decision. The aim of this paper was to compare the discriminatory power of four scores - the classic PSI and CURB65 ant the most recent SCAP and SMART-COP - in predicting major adverse events: death, ICU admission, need for invasive mechanical ventilation or vasopressor support in patients admitted with pneumococcal pneumonia.

METHODS

A five year retrospective study of patients admitted for pneumococcal pneumonia. Patients were stratified based on admission data and assigned to low-, intermediate-, and high-risk classes for each score. Results were obtained comparing low versus non-low risk classes.

RESULTS

We studied 142 episodes of hospitalization with 2 deaths and 10 patients needing mechanical ventilation and vasopressor support. The majority of patients were classified as low risk by all scores - we found high negative predictive values for all adverse events studied, the most negative value corresponding to the SCAP score. The more recent scores showed better accuracy for predicting ICU admission and need for ventilation or vasopressor support (mostly for the SCAP score with higher AUC values for all adverse events).

CONCLUSIONS

The rate of all adverse outcomes increased directly with increasing risk class in all scores. The new gravity scores appear to have a higher discriminatory power in all adverse events in our study, particularly, the SCAP score.

Behaviour and biomarkers of oxidative stress in Gambusia holbrooki after acute exposure to widely used pharmaceuticals and a detergent

Pharmaceuticals are continuously dispersed into the environment, as a result of human and veterinary use, and have become a relevant environmental concern. In the present study, the acute toxicity of three therapeutic agents (diazepam, clofibrate, and clofibric acid) and a detergent, sodium dodecylsulphate (SDS), to the euryhaline fish Gambusia holbrooki was evaluated. Special attention was devoted to oxidative stress parameters. G. holbrooki males, captured in the estuary of the Minho River (NW Portugal), were exposed for 96 h to the selected compounds. The following oxidative stress biomarkers were evaluated in gills and liver tissues: reduced and oxidised glutathione, lipid peroxidation, and several antioxidant enzymes, namely (1) total and selenium-dependent glutathione peroxidase (GPx), (2) glutathione reductase (GRed), (3) copper-zinc superoxide dismutase (Cu-ZnSOD) and manganese superoxide dismutase (MnSOD), and (4) glutathione-S-transferases (GSTs). In the particular case of diazepam, swimming behaviour was also evaluated. The obtained results indicate an overall diminished oxidative stress response caused by SDS and diazepam. Oxidative-based alterations were observed after exposure to clofibrate and clofibric acid, with modifications of several enzymatic activities. Diazepam caused evident behavioural changes: animals showed dark pigmentation and also abnormal postures, namely lethargy and anomalous movement.

Ecstasy-induced cell death in cortical neuronal cultures is serotonin 2A-receptor-dependent and potentiated under hyperthermia

Studies on 3,4-methylenedioxymethamphetamine ("ecstasy")-induced neurotoxicity mainly focus on damage of serotonergic terminals. Less attention has been given to neuronal cell death produced by 3,4-methylenedioxymethamphetamine and other amphetamines in areas including the cortex, striatum and thalamus. In the present study we investigated 3,4-methylenedioxymethamphetamine-induced neurotoxicity in neuronal serum free cultures from rat cortex. Since 3,4-methylenedioxymethamphetamine intake induces hyperthermia in both animals and humans, the experiments were performed under normal (36.5 degrees C) and hyperthermic conditions (40 degrees C). Our findings showed a dose-, time- and temperature-dependent apoptotic cell death induced by 3,4-methylenedioxymethamphetamine in cortical neurons. 3,4-Methylenedioxymethamphetamine-induced damage was potentiated under hyperthermia. The neurotoxicity was reduced by the serotonin 2A-receptor antagonists, ketanserin and (2R,4R)-5-[2-[2-[2-(3-methoxyphenyl)ethyl]phenoxy]ethyl]-1-methyl-3-pyrrolidinol hydrochloride, in both normothermic and hyperthermic conditions. (+/-)-2,5-Dimethoxy-4-iodoamphetamine hydrochloride, a model agonist for the serotonin 2A-receptor, also induced a dose- and time-dependent apoptotic cell death. Again, protection was provided by ketanserin and (2R,4R)-5-[2-[2-[2-(3-methoxyphenyl)ethyl]phenoxy]ethyl]-1-methyl-3-pyrrolidinol hydrochloride against (+/-)-2,5-dimethoxy-4-iodoamphetamine hydrochloride-induced neurotoxicity, thereby indicating that the 3,4-methylenedioxymethamphetamine stimulation of the serotonin 2A-receptor leads to neurotoxicity. This study provides for the first time evidence that direct 3,4-methylenedioxymethamphetamine serotonin 2A-receptor stimulation leads to neuronal cortical death. alpha-Phenyl-N-tert-butyl nitrone a free radical scavenger and the nitric oxide synthase inhibitor Nomega-nitro-L-arginine as well as the NMDA-receptor antagonist MK-801 provided protection under normothermia and hyperthermia, thereby suggesting the participation of free radicals in 3,4-methylenedioxymethamphetamine-induced cell death. Since 3,4-methylenedioxymethamphetamine serotonin 2A-receptor agonistic properties lead to neuronal death, clinically available atypical antipsychotic drugs with serotonin 2A-antagonistic properties could be a valuable therapeutic tool against 3,4-methylenedioxymethamphetamine-induced neurodegeneration.