Unlocking the molecular realm: advanced approaches for identifying clinically and environmentally relevant bacteria

Rapid, effective, and specific identification of clinical and environmental bacterial pathogens is of major importance for their control. Traditionally, bacteria have been identified by phenotypic methods based on morphological, biochemical, and metabolic properties. While these methods are very useful in clinical practice, they have limitations including a poor ability to differentiate within and between species and time-consuming workflows. Newly developed molecular methods can greatly improve the accuracy of taxonomic characterization, identifying specific strains of medical or environmental importance. However, due to high costs and the need for trained professionals, these methods are not yet routine in diagnostic laboratories. Thus, disseminating knowledge on advances in molecular identification techniques is pivotal to make these methodologies accessible. The objective of this work was to review and discuss current molecular techniques for bacteria identification aiming to track and monitor microbial agents in clinical and environmental samples.

Molecular Sensitization Profile to Dermatophagoides pteronyssinus Dust Mite in Portugal

OBJECTIVE

To analyze component resolved diagnosis to Dermatophagoides pteronyssinus (Der p) in patients with respiratory allergy and its relationship with clinical severity in different geographical areas.

METHODS

217 patients (mean age 25.85±12.7 years; 51.16% females) were included, selected from 13 centers in Portugal (5 from North, n=65). All had allergic rhinitis, with or without asthma, and had positive skin prick tests to at least one dust mite. Specific IgE (sIgE) to Der p, Dermatophagoides farinae, Lepidoglyphus destructor, Der p1, Der p 2, Der p 10 and Der p 23 were determined by ImmunoCAP. Statistical analysis (Mann Whitney U test) compared patients with rhinitis vs rhinitis and asthma; mild vsmoderate-to-severe rhinitis; North vs South.

RESULTS

Prevalence of sensitization was 98.2% to Der p, and 72.4%, 89.4%, 9.7% and 77% to Der p 1, Der p 2, Der p 10 and Der p 23, respectively. Corresponding median sIgE levelswere 8.56, 17.7, 0.01 and 3.95 kUA/L. sIgE to all allergens was higher in patients with moderate-to-severe rhinitis and rhinitis with asthma but not statistically significant (NSS). sIgE to Der p 2 was significantly higher in the South when compared with the North (p=0.0496).

CONCLUSIONS

sensitization to Der p is the most common in Portugal. Der p 2 had the highest prevalence and median sIgE levels. All sIgE to molecular components were higher in more symptomatic patients (NSS). sIgE to Der p 2 was higher in the South, which may be related to the warmer temperature and/or the larger sample size.

Skin tests and challenge-based drug allergy diagnosis: a retrospective study of patients with confirmed drug allergy

Summary

Objectives. To describe clinical manifestations and performed diagnostic workup, focusing drug challenge tests (DCT), in patients with drug allergy. Methods. Retrospective study including all patients with skin tests (STs) or DCT-based drug allergy diagnosis, between 01/2014 - 06/2018 in a Portuguese allergy unit. Data were collected from electronic and paper-based clinical records. Results. We had 75 drug allergy diagnoses. Most index reactions were mild and major or equal 1 hour after drug intake. 59 (78%) diagnoses were based on DCTs, all based on multistep protocols with major or equal 3 predicted steps. Only 10% of the DCT were positive during up-dosing; timing and severity of the index reaction predicted DCT interruption during up-dosing. Conclusions. Most drug allergy diagnoses were based on multistep DCT. The identified predictors of DCT interruption during up-dosing can support the development of more personalized DCTs protocols.

Clinodiplosis agerati (Diptera, Cecidomyiidae), a new galling species associated with Ageratum conyzoides (Asteraceae) from Brazil

Abstract Clinodiplosis agerati, a new galling species that induces stem galls on Ageratum conyzoides (Asteraceae) is described and illustrated (larva, pupa, male, female and gall) based on material collected in Minas Gerais, Brazil. The new species is compared with the other Neotropical species. This is the first record of the Clinodiplosis in Ageratum.

Asthma control in the Portuguese National Asthma Survey

INTRODUCTION

We aimed (1) to measure asthma control using a structure-questionnaire and patient self-perception of asthma-control in the Portuguese National Asthma Survey (INAsma) and (2) to study the relationship between asthma control and asthma-related quality of life.

METHODS

We analyze data of asthma patients from a cross-sectional, nationwide telephone interview study - INAsma. Controlled asthma was defined as CARAT global score >24 or CARAT lower airways score ≥16. Mini-AQLQ was used to measure quality of life.

RESULTS

Two hundred and seven (56.9% [95%CI: 51.8-62.0]) of the 364 patients had controlled asthma. Most patients with non-controlled asthma (88%) perceived their disease as controlled. Patients with controlled asthma presented higher mini-AQLQ scores (median, P25-P75; 6.6, 6.0-6.9) than those with non-controlled asthma (4.9, 3.7-5.7) (p<0.001) and a significant positive correlation between CARAT and mini-AQLQ scores was observed (r=0.706; p<0.001).

CONCLUSION

More than half of the Portuguese patients presented controlled asthma and showed significantly better asthma-related quality of life. Almost 9 out of 10 patients with non-controlled disease have poor perception of their asthma control, which may hinder them from seeking better asthma control.

Morbidity among nursing personnel and its association with working conditions and work organization

INTRODUCTION

Work organization patterns and working conditions experienced by nursing personnel in the hospital settings may be associated to increased morbidity among these health workers.

AIM

To estimate the prevalence and factors associated with self-reported diseases among nursing personnel at the emergency hospital in Rio Branco/State of Acre, Brazil.

METHODS

A cross-sectional study was conducted involving 272 participants who answered a questionnaire including sociodemographic characteristics, working conditions, lifestyles, work ability, and a fatigue perception scale. The self-reported diseases in the 12 months prior to data collection were considered the dependent variable.

RESULTS

A total of 85.7% of the participants reported one or more diseases in the past 12 months. Most prevalent diseases were: musculoskeletal diseases (37.1%), digestive diseases (28.7%), mental disorders (28.3%), work injuries (27.9%), and respiratory diseases (26.8%). The following significant variables remained in the final model: high work demands (OR 2.69), reported fatigue (OR 3.59), night work (OR 6.55) and being a technician or nursing assistant (OR 4.23).

CONCLUSIONS

Variables related to working conditions and work organization were associated with the occurrence of reported diseases among nursing professionals. Health promotion measures at work require a comprehensive approach including the working conditions and the work organization.

Desempenho de vacas em lactação alimentadas com dietas contendo torta de macaúba

Avaliaram-se o consumo de nutrientes e a produção e composição do leite de vacas da raça Holandesa alimentadas com dietas contendo diferentes quantidades de inclusão de torta de macaúba. Oito animais foram distribuídos em dois quadrados latinos 4x4, sendo quatro tratamentos, 0, 100, 200 e 300g kg-1 de TM na matéria seca da dieta, e quatro períodos experimentais de 21 dias, 14 de adaptação e sete de avaliações. A adição de quantidades crescentes de torta de macaúba à dieta alterou o consumo de matéria seca, matéria orgânica, proteína bruta, extrato etéreo, fibra em detergente neutro, carboidratos não fibrosos, produção e os teores de lactose, extrato seco desengordurado e sólidos totais do leite, bem como a eficiência alimentar e a digestibilidade da matéria seca. Por outro lado, não foi verificada diferença nos teores de gordura do leite. A adição da TM em até 300g kg-1 da dieta comprometeu o consumo e o desempenho produtivo dos animais.

Validation of total and specific IgE measurements in induced sputum

BACKGROUND AND OBJECTIVES

Soluble components are increasingly analyzed in induced sputum supernatant. However, only a few studies have measured total or specific immunoglobulin (Ig) E in sputum and none have attempted to validate it. We aim to validate laboratory measurements of total and specific IgE in induced sputum supernatant and to evaluate the influence of sputum processing with dithiothreitol (DTT) on IgE measurements.

METHODS

Total and specific IgE were measured by ImmunoCAP and the process was validated using sputum spiking experiments with total and specific IgE (to Dermatophagoides pteronyssinus and Phleum pratense) over a range of concentrations according to international recommendations.The Wilcoxon signed-ranks test was used for within-group comparisons and intraclass correlation coefficients were used to evaluate agreement between measurements. Two-tailed P values lower than .05 were considered significant.

RESULTS

Samples from 18 patients (13 with interstitial lung disease, 2 with allergic asthma, and 3 healthy controls; 12 men; mean [SD] age, 45.6 [15.8] years) were evaluated. Median total IgE was 5.4 kU/L (interquartile range, 4.0-6.0 kU/L). Specific IgE levels to D. pteronyssinus and P. pratense were below 0.35 kUA/L in all samples. Recovery rates were above 80% for total and specific IgE over a wide range of values. No differences were found in total IgE measurements of sputum dispersed with DTT or phosphate-buffered saline, with a good intraclass correlation coefficient between both measurements (0.81, P=.01).

CONCLUSIONS

Total and specific IgE measurements performed in induced sputum with a commercially available immunoassay are valid over a wide range of IgE levels.

Microarray based IgE detection in poly-sensitized allergic patients with suspected food allergy - an approach in four clinical cases

BACKGROUND

Component-resolved diagnosis and microarray technology have been recently introduced into clinical allergy practice, and may be particularly useful in poly-sensitized allergic patients.

METHODS

We compare the clinical usefulness of a microarray-based IgE detection assay (ISAC(®)) with skin tests and specific IgE with standard allergens (sIgE) or their monocomponents in four case reports of patients poly-sensitized to aeroallergens and food.

RESULTS

Case 1: a woman with rhinitis, oral allergy syndrome to several fruits and anaphylaxis to cherry. Diagnostic tests supported non-specific lipid transfer proteins (nsLTPs) primary sensitization. Case 2: a woman with exercise-induced asthma, rhino-conjunctivitis and oral allergy syndrome to fresh fruits of different families. A diagnosis of primary grass and weed pollen allergy with profilin and pathogenesis-related protein family 10 (PR-10) cross-reactive food allergy was proposed. Case 3: a man with atopic eczema, asthma, rhinitis, and multiple anaphylactic episodes with cashew nuts and oral allergy syndrome to fruits. The diagnostic workup supported a primary birch pollen allergy with PR-10 and nsLTPs cross-reactive food allergy. Case 4: a woman with rhino-conjunctivitis, per-operative anaphylaxis due to latex and recent pharyngeal angio-oedema episodes. The diagnosis was a primary grass and weed pollen allergy with equivocal profilin sensitization and no obvious cross-reactivity mediated by nsLTPs sensitization.

CONCLUSIONS

The possibility to carry out multiple sIgE measurements with single protein allergens, in particular with the microarray technique, is a useful, simple and non-invasive diagnostic tool in complex poly-sensitized allergic patients.

Clinical efficacy of web-based versus standard asthma self-management

BACKGROUND

Guided self-management is an important component of asthma care. Most trials have evaluated paper-based strategies. The effectiveness of new communication technologies remains uncertain.

OBJECTIVES

To compare the feasibility and clinical outcomes of a standard paper-based asthma self-management strategy with web-based strategies.

METHODS

In a crossover trial, 21 patients using inhaled corticosteroids and long-acting B2-agonists (mean [SD] age 29 [10] years) were randomly assigned to use a sequence of web-based and paper-based diary and action plan. Quality of life, asthma control, lung function, and airway inflammation were assessed using the Asthma Life Quality Questionnaire (ALQ), Asthma Control Questionnaire (ACQ-5), Mini Asthma Quality of Life Questionnaire (Mini AQLQ), and office spirometry. The ratio of forced expiratory volume in the first second of expiration (FEV1) to peak expiratory flow (PEF) rate (PiKo-1) and fraction of exhaled nitric oxide (FE(NO)) were monitored. The main clinical outcomes were asthma control and FE(NO). Quality of data and adherence to monitoring tools were the main process outcomes.

RESULTS

Significant improvements were observed in the AQL and ACQ scores, although lung function did not change. FE(NO) was significantly reduced only after a web-based strategy but a significant period effect occurred (P = .006). There were no differences in clinical outcomes between web-based and paper-based management. No intervention-related adverse effects were observed. Adherence seemed higher with the paper-based strategy (P < .001). However, paper data were unreliable when compared to automatic daily electronic FEV1/PEF records. Twelve patients were very interested in continuing self-management with the web-based approach compared with 2 in using paper tools (P = .002).

CONCLUSIONS

Web-based management was feasible, safe, and preferred by patients. Short-term outcomes were at least as good, and data quality was improved.

Induced sputum in children: success determinants, safety, and cell profiles

BACKGROUND

Sputum induction is a noninvasive method for the assessment of airway inflammation.

OBJECTIVES

To evaluate the safety of the procedure and the clinical predictors of successful induction, and to analyze the relationship between sputum cell counts and clinical features in asthmatic and nonasthmatic children.

METHODS

We reviewed sputum inductions performed in our department between 2006 and 2008 in individuals under 18 years; 34 asthmatic and 24 nonasthmatic children were included. Sputum induction was performed with 4.5% saline for 5-minute periods with salbutamol pretreatment. The most viscid portions were selected for processing. Inductions which were tolerated for less than 4 minutes or which produced a sample volume of less than 1 mL or a sample with a squamous cell percentage of over 80% were considered unsuccessful.

RESULTS

Sputum induction was successful in 43 (74%) of the 58 children studied.The total median induction time was 15 minutes (interquartile range, 10-15 minutes). Only 7 individuals (12%) experienced mild symptoms, which were easily reversed with salbutamol inhalation in all cases. The mean (SD) overall PEF variation with induction was -2.5% (7%), with no significant differences between asthmatics and nonasthmatics. Asthmatics had significantly higher total cell counts (P = .007), macrophages (P = .033), and relatively fewer neutrophils (P = .003) than nonasthmatics; metachromatic cells were rare and seen only in asthmatics (P = .026). We found a positive correlation between exhaled nitric oxide and sputum eosinophil count (r = 0.363, P = .017).

CONCLUSIONS

Sputum induction is a safe, noninvasive, and feasible procedure that allows the direct assessment of airway inflammation in most children.

Cyfra 21.1, TPS and SCC in squamous cell carcinoma of larynx

BACKGROUND

Serologic tumor markers are actually a valuable tool for diagnosis, management and follow up in some cancer types. The concentrations of Cyfra 21.1, SCC and TPS has been analysed in several groups of head and neck tumors, but exclusively in larynx there are no studies concerning this subject.

AIMS

The purpose of the present study was to assess the expression of serum fragments of cytokeratins (CK's) 18/19, and squamous cell carcinoma antigen (SCCA) in a same group of patients with squamous cell carcinoma of larynx, and correlate the results with tumor localisation, T, stage, histology, presence of regional metastasis, and smoking habits.

METHODS

Forty six patients treated at the Department of Otorhinolaryngology, Porto Center of the Portuguese Institute of Oncology were enrolled in the study. Blood samples were obtained before treatment, and determinations effectuated using standard commercial available kits.

RESULTS

Although serum concentrations of Cyfra 21.1, TPS and SCC were not significantly elevated in patients with laryngeal cancer, more expressive levels namely for TPS were observed in advanced supraglotic and metastasis tumors independent of the differentiation degree.

Forced oscillation technique to evaluate tracheostenosis in patients with neurologic injury

STUDY OBJECTIVES

To determine the utility of forced oscillation technique (FOT) for measuring pulmonary resistance and reactance in patients with central nervous system injuries, for detection and follow-up of posttracheostomy tracheal stenosis.

DESIGN

Case series.

SETTING

A rehabilitation hospital, Brasilia, Distrito Federal, Brazil.

PATIENTS

Ten consecutive neurologically impaired patients, who had previously undergone tracheostomies, with tracheostenosis without current tracheostomy or other tracheal lesion.

INTERVENTIONS AND MEASUREMENTS

FOT evaluations were compared to tracheal diameter before and after bronchoscopic tracheostenosis dilatation procedures. Forced spirometry examinations were also obtained and compared.

RESULTS

Tracheal stenotic lesions were characterized by marked increase in resistance and reduction in reactance at low frequency and a marked increase in resonance frequency (Rf). Consistent reversal of this pattern with large reductions in total impedance of the respiratory system (Zresp) Rf and resistance at 5 Hz (R 5 Hz) were noted in all patients after each successful dilatation. Diameter of the stenosis was strongly correlated with Rf, Zresp, and R 5 Hz. The change in diameter before and after dilatation was similarly correlated with the changes in FOT values of Rf and Zresp. Spirometry values did not correlate well with the diameter of the tracheal stenosis.

CONCLUSION

The strong correlation of Rf, Zresp, and R 5 Hz to diameter of tracheostenosis suggests a previously unappreciated role for FOT in the noninvasive detection and follow-up of airway stenosis. This may be especially useful for patients with concomitant neurologic disabilities who are at risk of airway stenosis.

Successful prevention of hiv transmission from mother to infant in Brazil using a multidisciplinary team approach

OBJECTIVES

To determine the HIV vertical transmission rate (VTR) and associated risk factors by use of zidovudine and infant care education in Brazil.

METHODS

Since 1995, a prospective cohort of HIV infected pregnant women has been followed at the Federal University of Rio de Janeiro. A multidisciplinary team was established to implement the best available strategy to prevent maternal-infant HIV transmission. Patients with AIDS or low CD(4) and high viral load received anti-retroviral drugs in addition to zidovudine. Children were considered infected if they had 2 positive PCR-RNA tests between 1 and 4 months of age, or were HIV antibody positive after 18 months. Education regarding infant treatment and use of formula instead of breast feeding was provided.

RESULTS

Between 1995 and August, 2000, HIV status was determined for 145 infants. Compliance with intra-partum treatment, infant treatment and use of formula was 88.2%. Intra-partum zidovudine treatment was completed in 134/145 (92.6%) of patients; 88.1% had rupture of membranes < 4 hours; 85.4% of mothers were asymptomatic. The mean CD(4) count was 428.4 cells and mean viral load 39,050 copies. HIV vertical transmission rate was 4/145 (2.75%; CI: 0.1%-5.4%). The only risk factor significantly associated with transmission was a failure to use zidovudine intra-partum in 2 of the 4 mothers (50% versus 6.4% in non-transmitting mothers). A trend toward low CD(4) and high viral load at entry, and rupture of membranes > 4 hours were associated with increased HIV transmission.

CONCLUSION

HIV vertical transmission in Brazil was reduced to a level similar to other countries with the most effective prevention programs using a multidisciplinary team approach. A high level of compliance for use of anti-retroviral drugs, the provision of health education to mothers, and use of formula for all exposed infants.