Early-life external exposome in children 2-5 years old in Colombia

Exposome studies are advancing in high-income countries to understand how multiple environmental exposures impact health. However, there is a significant research gap in low- and middle-income and tropical countries. We aimed to describe the spatiotemporal variation of the external exposome, its correlation structure between and within exposure groups, and its dimensionality. A one-year follow-up cohort study of 506 children under 5 in two cities in Colombia was conducted to evaluate asthma, acute respiratory infections, and DNA damage. We examined 48 environmental exposures during pregnancy and 168 during childhood in eight exposure groups, including atmospheric pollutants, natural spaces, meteorology, built environment, traffic, indoor exposure, and socioeconomic capital. The exposome was estimated using geographic information systems, remote sensing, spatiotemporal modeling, and questionnaires. The median age of children at study entry was 3.7 years (interquartile range: 2.9-4.3). Air pollution and natural spaces exposure decreased from pregnancy to childhood, while socioeconomic capital increased. The highest median correlations within exposure groups were observed in meteorology (r = 0.85), traffic (r = 0.83), and atmospheric pollutants (r = 0.64). Important correlations between variables from different exposure groups were found, such as atmospheric pollutants and meteorology (r = 0.76), natural spaces (r = -0.34), and the built environment (r = 0.53). Twenty principal components explained 70%, and 57 explained 95% of the total variance in the childhood exposome. Our findings show that there is an important spatiotemporal variation in the exposome of children under 5. This is the first characterization of the external exposome in urban areas of Latin America and highlights its complexity, but also the need to better characterize and understand the exposome in order to optimize its analysis and applications in local interventions aimed at improving the health conditions and well-being of the child population and contributing to environmental health decision-making.

Inflammatory Patterns Associated with Legionella in HIV and Pneumonia Coinfections

Legionella infections have a propensity for occurring in HIV-infected individuals, with immunosuppressed individuals tending to present with more severe disease. However, understanding regarding the Legionella host response in immune compromised individuals is lacking. This study investigated the inflammatory profiles associated with Legionella infection in patients hospitalized with HIV and pneumonia in Medellín, Colombia from February 2007 to April 2014, and correlated these profiles with clinical outcomes. Sample aliquots from the Colombian cohort were shipped to Canada where Legionella infections and systemic cytokine profiles were determined using real-time PCR and bead-based technology, respectively. To determine the effect of Legionella coinfection on clinical outcome, a patient database was consulted, comparing laboratory results and outcomes between Legionella-positive and -negative individuals. Principal component analysis revealed higher plasma concentrations of eotaxin, IP-10 and MCP-1 (p = 0.0046) during Legionella infection. Individuals with this immune profile also had higher rates of intensive care unit admissions (adjusted relative risk 1.047 [95% confidence interval 1.027-1.066]). Results demonstrate that systemic markers of monocyte/macrophage activation and differentiation (eotaxin, MCP-1, and IP-10) are associated with Legionella infection and worse patient outcomes. Further investigations are warranted to determine how this cytokine profile may play a role in Legionella pneumonia pathogenesis or immunity.

Results of salvage neck dissection after chemoradiation in locally advanced head and neck squamous cell carcinoma

PURPOSE

Salvage surgery is mandatory when regional persistence/recurrence after chemoradiation. The aim of this study is to describe the outcomes of salvage surgery.

METHODS

A retrospective study was conducted in patients with locally advanced head and neck squamous cell carcinoma that were primarily treated with chemorradiation and underwent salvage neck dissection (ND) with suspected recurrent/persistent nodal disease. All patients had a response evaluation at 12 weeks through clinical examination and computed tomography-positron emission tomography. Decision for ND was taken in case of suspected persistence or if there was suspicion of recurrence, histologically confirmed.

RESULTS

There were 40 patients included. 32/40 (80%) ND were done because of confirmed/suspected persistence and 8/40 (20%) were done because of recurrences. Persistence was confirmed histologically in 14/32 (43.8%) cases and recurrence in 6/8 (75%) cases. Median survival from diagnosis was 39 months (95% CI 28.162-49.838). Significant differences were observed between patients who had viable tumour cells in the sample and those who did not, but the differences were only significant when only deaths due to tumour progression were considered (p = 0.014). 14/32 (43.8%) patients with suspected or confirmed persistence developed a recurrence after the ND and 3/8 (37.5%) patients with suspected or confirmed recurrence developed a new recurrence. New recurrences were more frequent in cases that had viable tumor in the specimen.

CONCLUSIONS

Patients with nodal persistence/recurrence have a poor prognosis, even after salvage surgery. However, in a substantial number of patients the disease is controlled after ND, so it should be offer to these patients.

Markers of Inflammation, Tissue Damage, and Fibrosis in Individuals Diagnosed with Human Immunodeficiency Virus and Pneumonia: A Cohort Study

Previous studies have noted that persons living with human immunodeficiency virus (HIV) experience persistent lung dysfunction after an episode of community-acquired pneumonia (CAP), although the underlying mechanisms remain unclear. We hypothesized that inflammation during pneumonia triggers increased tissue damage and accelerated pulmonary fibrosis, resulting in a gradual loss of lung function. We carried out a prospective cohort study of people diagnosed with CAP and/or HIV between 2016 and 2018 in three clinical institutions in Medellín, Colombia. Clinical data, blood samples, and pulmonary function tests (PFTs) were collected at baseline. Forty-one patients were included, divided into two groups: HIV and CAP (n = 17) and HIV alone (n = 24). We compared the concentrations of 17 molecules and PFT values between the groups. Patients with HIV and pneumonia presented elevated levels of cytokines and chemokines (IL-6, IL-8, IL-18, IL-1RA, IL-10, IP-10, MCP-1, and MIP-1β) compared to those with only HIV. A marked pulmonary dysfunction was evidenced by significant reductions in FEF25, FEF25-75, and FEV1. The correlation between these immune mediators and lung function parameters supports the connection between pneumonia-associated inflammation and end organ lung dysfunction. A low CD4 cell count (<200 cells/μL) predicted inflammation and lung dysfunction. These results underscore the need for targeted clinical approaches to mitigate the adverse impacts of CAP on lung function in this population.

Bovine leukemia virus detection in humans: A systematic review and meta-analysis

To review the available studies on the frequency of detection of the bovine leukemia virus in human samples, a systematic review with meta-analysis of the scientific literature was carried out, including papers published in English, Spanish, and Portuguese in 5 multidisciplinary databases. We collected information from different populations following a detailed and reproducible search protocol in which two researchers verified the inclusion and exclusion criteria. We identified 759 articles, of which only 33 met the inclusion criteria. Analyzed studies reported that the presence of the virus was measured in human samples, such as paraffin-embedded breast tissue and peripheral blood from 10,398 individuals, through serological and molecular techniques. An overall virus frequency of 27% (Ranging between 17 and 37%) was observed, with a high-frequency data heterogeneity between studies. The presence of this virus in different human biological samples suggests the need to investigate further its transmission route to humans and its potential role in developing and progressing diseases.

Test Bench for Highly Segmented GRIT Double-Sided Silicon Strip Detectors: A Detector Quality Control Protocol

This work deals with the characteristics of highly segmented double-sided silicon detectors. These are fundamental parts in many new state-of-the-art particle detection systems, and therefore they must perform optimally. We propose a test bench that can handle 256 electronic channels with off-the-shelf equipment, as well as a detector quality control protocol to ensure that the detectors meet the requirements. Detectors with a large number of strips bring new technological challenges and issues that need to be carefully monitored and understood. One of the standard 500 μm thick detectors of the GRIT array was investigated, undergoing studies that revealed its IV curve, charge collection efficiency, and energy resolution. From the data obtained, we calculated, among other things, the depletion voltage (110 V), the resistivity of the bulk material (9 kΩ·cm), and the electronic noise contribution (8 keV). We present, for the first time, a methodology called "the energy triangle'' to visualize the effect of charge sharing between two adjacent strips and to study the hit distribution with the interstrip-to-strip hit ratio (ISR).

Tuberculosis in Prisons: Importance of Considering the Clustering in the Analysis of Cross-Sectional Studies

The level of clustering and the adjustment by cluster-robust standard errors have yet to be widely considered and reported in cross-sectional studies of tuberculosis (TB) in prisons. In two cross-sectional studies of people deprived of liberty (PDL) in Medellin, we evaluated the impact of adjustment versus failure to adjust by clustering on prevalence ratio (PR) and 95% confidence interval (CI). We used log-binomial regression, Poisson regression, generalized estimating equations (GEE), and mixed-effects regression models. We used cluster-robust standard errors and bias-corrected standard errors. The odds ratio (OR) was 20% higher than the PR when the TB prevalence was >10% in at least one of the exposure factors. When there are three levels of clusters (city, prison, and courtyard), the cluster that had the strongest effect was the courtyard, and the 95% CI estimated with GEE and mixed-effect models were narrower than those estimated with Poisson and binomial models. Exposure factors lost their significance when we used bias-corrected standard errors due to the smaller number of clusters. Tuberculosis transmission dynamics in prisons dictate a strong cluster effect that needs to be considered and adjusted for. The omission of cluster structure and bias-corrected by the small number of clusters can lead to wrong inferences.

Characterization of the external exposome and its contribution to the clinical respiratory and early biological effects in children: The PROMESA cohort study protocol

BACKGROUND

Air pollution contains a mixture of different pollutants from multiple sources. However, the interaction of these pollutants with other environmental exposures, as well as their harmful effects on children under five in tropical countries, is not well known.

OBJECTIVE

This study aims to characterize the external exposome (ambient and indoor exposures) and its contribution to clinical respiratory and early biological effects in children.

MATERIALS AND METHODS

A cohort study will be conducted on children under five (n = 500) with a one-year follow-up. Enrolled children will be followed monthly (phone call) and at months 6 and 12 (in person) post-enrolment with upper and lower Acute Respiratory Infections (ARI) examinations, asthma development, asthma control, and genotoxic damage. The asthma diagnosis will be pediatric pulmonologist-based and a standardized protocol will be used. Exposure, effect, and susceptibility biomarkers will be measured on buccal cells samples. For environmental exposures PM2.5 will be sampled, and questionnaires, geographic information, dispersion models and Land Use Regression models for PM2.5 and NO2 will be used. Different statistical methods that include Bayesian and machine learning techniques will be used for the ambient and indoor exposures-and outcomes. This study was approved by the ethics committee at Universidad Pontificia Bolivariana.

EXPECTED STUDY OUTCOMES/FINDINGS

To estimate i) The toxic effect of particulate matter transcending the approach based on pollutant concentration levels; ii) The risk of developing an upper and lower ARI, based on different exposure windows; iii) A baseline of early biological damage in children under five, and describe its progression after a one-year follow-up; and iv) How physical and chemical PM2.5 characteristics influence toxicity and children's health.

Cytokine levels as predictors of mortality in critically ill patients with severe COVID-19 pneumonia: Case-control study nested within a cohort in Colombia

Background

High levels of different cytokines have been associated in COVID-19 as predictors of mortality; however, not all studies have found this association and its role to cause multi-organ failure and death has not been fully defined. This study aimed to investigate the association of the levels of 10 cytokines with mortality in patients with COVID-19 admitted to the intensive care unit (ICU).

Materials and methods

This is a case-control study nested within a cohort of patients with COVID-19 who were on mechanical ventilation and were not hospitalized for more than 48 h across nine ICUs in Medellín, Colombia. Serum samples were collected upon admission to the ICU and 7 days later and used to measure cytokine levels.

Results

Upon admission, no differences in mortality between the cytokine levels were observed when comparisons were made quantitatively. However, in the multivariate analysis, patients with median IL-1β levels <1.365 pg/ml showed an increase in mortality (OR = 3.1; 1.24<7.71; p = 0.015). On day 7 in the ICU, IL-1β median levels were lower (0.34 vs. 2.41 pg/ml, p = 0.042) and IL-10 higher (2.08 vs. 1.05 pg/ml, p = 0.009) in patients who died. However, in the multivariate analysis, only IL-12p70 was associated with mortality (OR = 0.23; 0.07<0.73; p = 0.012). The mean difference in the levels between day 1 and day 7 decreased in both IFN-γ (3.939 pg/ml, p < 0.039) and in IL-18 (16.312 pg/ml, p < 0.014) in the patients who died. A low IL-1β/IL-10 ratio was associated with mortality on both day 1 and day 7, while an IL-1β/IL-10 ratio below the cut-off on day 7 was associated with decreased survival. The lowest TNFα/IL-10 ratio was associated with mortality only on day 7.

Conclusion

At the time of admission, patients with median IL-1β levels lower than 1.365 pg/ml had increased mortality. An IL-1β/IL-10 ratio <2 at day 7 and IL-12p70 levels >1.666 pg/ml was associated with decreased survival.

Gene expression profiling identifies candidate biomarkers for new latent tuberculosis infections. A cohort study

Objective

To determine the gene expression profile in individuals with new latent tuberculosis infection (LTBI), and to compare them with people with active tuberculosis (TB) and those exposed to TB but not infected.

Design

A prospective cohort study. Recruitment and follow-up were conducted between September 2016 to December 2018. Gene expression and data processing and analysis from April 2019 to April 2021.

Setting

Two male Colombian prisons.

Participants

15 new tuberculin skin test (TST) converters (negative TST at baseline that became positive during follow-up), 11 people that continued with a negative TST after two years of follow-up, and 10 people with pulmonary ATB.

Main outcome measures

Gene expression profile using RNA sequencing from PBMC samples. The differential expression was assessed using the DESeq2 package in Bioconductor. Genes with |logFC| >1.0 and an adjusted p-value < 0.1 were differentially expressed. We analyzed the differences in the enrichment of KEGG pathways in each group using InterMiner.

Results

The gene expression was affected by the time of incarceration. We identified group-specific differentially expressed genes between the groups: 289 genes in people with a new LTBI and short incarceration (less than three months of incarceration), 117 in those with LTBI and long incarceration (one or more years of incarceration), 26 in ATB, and 276 in the exposed but non-infected individuals. Four pathways encompassed the largest number of down and up-regulated genes among individuals with LTBI and short incarceration: cytokine signaling, signal transduction, neutrophil degranulation, and innate immune system. In individuals with LTBI and long incarceration, the only enriched pathway within up-regulated genes was Emi1 phosphorylation.

Conclusions

Recent infection with MTB is associated with an identifiable RNA pattern related to innate immune system pathways that can be used to prioritize LTBI treatment for those at greatest risk for developing active TB.

Tick-Borne-Agents Detection in Patients with Acute Febrile Syndrome and Ticks from Magdalena Medio, Colombia

Acute febrile illness (AFI) is a morbid condition with a sudden onset of fever with at least seven days of evolution, where no signs or symptoms related to an apparent infection have been identified. In Latin America, a high proportion of disease is typically due to malaria and arboviruses. However, among the infectious etiologies, tick-borne diseases (TBDs) should also be considered, especially in areas where people come into direct contact with these arthropods. This study aims to describe the etiology and epidemiology related to tick-borne agents in patients with AFI and the tick’s natural infection by agents of TBD in the rural tropical Magdalena Medio region in Colombia, and explore the factors associated with the presence of Coxiella burnetii infection. We conduct a cohort study enrolling 271 patients with AFI to detect the bacteria of the genera Anaplasma, Ehrlichia, Coxiella, Rickettsia, Borrelia, and Francisella through molecular techniques, and additionally evaluate the presence of IgG antibodies with commercially available kits. We also conduct tick collection in the patient’s households or workplaces for the molecular screening of the same bacterial genera. Seropositivity to IgG antibodies was obtained for all the bacteria analyzed, with Francisella being the most common at 39.5% (107/271), followed by R. rickettsii at 31.4% (85/271), Ehrlichia at 26.9% (73/271), R. typhi at 15.5% (42/271), Anaplasma at 14.4% (39/271), and Borrelia at 6.6% (18/271). However, these bacteria were not detected by the molecular techniques used. Coxiella burnetii infection was detected in 39.5% of the patients: 49.5% only by phase I and II IgG antibodies, 33.6% only by real-time PCR, and 16.8% had a concordant positive result for both techniques. A total of 191 adult ticks, 111 females and 80 males, were collected and identified as Rhipicephalus sanguineus s.l. and Rhipicephalus microplus. In the 169 adult ticks in which natural infection was evaluated, Ehrlichia spp. was detected in 21.3% (36/169), Coxiella spp. in 11.8% (20/169), and Anaplasma spp. in 4.7% (8/169). In conclusion, we identified the prior exposition to Francisella, Anaplasma, Ehrlichia, Rickettsia, Borrelia, and Coxiella in patients through serological tests. We also detected the infection of C. burnetii using molecular techniques. In the ticks, we identified bacteria of the genera Coxiella, Anaplasma, and Ehrlichia. These results suggest the importance of these zoonotic agents as possible causes of AFI in this region.

Cytotoxicity and Genotoxicity of Azobenzene-Based Polymeric Nanocarriers for Phototriggered Drug Release and Biomedical Applications

Drug nanoencapsulation increases the availability, pharmacokinetics, and concentration efficiency for therapeutic regimes. Azobenzene light-responsive molecules experience a hydrophobicity change from a polar to an apolar tendency by trans–cis photoisomerization upon UV irradiation. Polymeric photoresponse nanoparticles (PPNPs) based on azobenzene compounds and biopolymers such as chitosan derivatives show prospects of photodelivering drugs into cells with accelerated kinetics, enhancing their therapeutic effect. PPNP biocompatibility studies detect the safe concentrations for their administration and reduce the chance of side effects, improving the effectiveness of a potential treatment. Here, we report on a PPNP biocompatibility evaluation of viability and the first genotoxicity study of azobenzene-based PPNPs. Cell line models from human ventricular cardiomyocytes (RL14), as well as mouse fibroblasts (NIH3T3) as proof of concept, were exposed to different concentrations of azobenzene-based PPNPs and their precursors to evaluate the consequences on mitochondrial metabolism (MTT assay), the number of viable cells (trypan blue exclusion test), and deoxyribonucleic acid (DNA) damage (comet assay). Lethal concentrations of 50 (LC50) of the PPNPs and their precursors were higher than the required drug release and synthesis concentrations. The PPNPs affected the cell membrane at concentrations higher than 2 mg/mL, and lower concentrations exhibited lesser damage to cellular genetic material. An azobenzene derivative functionalized with a biopolymer to assemble PPNPs demonstrated biocompatibility with the evaluated cell lines. The PPNPs encapsulated Nile red and dofetilide separately as model and antiarrhythmic drugs, respectively, and delivered upon UV irradiation, proving the phototriggered drug release concept. Biocompatible PPNPs are a promising technology for fast drug release with high cell interaction opening new opportunities for azobenzene biomedical applications.

Diagnostic concordance between BioFire® FilmArray® Pneumonia Panel and culture in patients with COVID-19 pneumonia admitted to intensive care units: the experience of the third wave in eight hospitals in Colombia

Background

The detection of coinfections is important to initiate appropriate antimicrobial therapy. Molecular diagnostic testing identifies pathogens at a greater rate than conventional microbiology. We assessed both bacterial coinfections identified via culture or the BioFire® FilmArray® Pneumonia Panel (FA-PNEU) in patients infected with SARS-CoV-2 in the ICU and the concordance between these techniques.

Methods

This was a prospective study of patients with SARS-CoV-2 who were hospitalized for no more than 48 h and on mechanical ventilation for no longer than 24 h in 8 ICUs in Medellín, Colombia. We studied mini-bronchoalveolar lavage or endotracheal aspirate samples processed via conventional culture and the FA-PNEU. Coinfection was defined as the identification of a respiratory pathogen using the FA-PNEU or cultures. Serum samples of leukocytes, C-reactive protein, and procalcitonin were taken on the first day of intubation. We analyzed the empirical antibiotics and the changes in antibiotic management according to the results of the FA-PNEUM and cultures.

Results

Of 110 patients whose samples underwent both methods, FA-PNEU- and culture-positive samples comprised 24.54% versus 17.27%, respectively. Eighteen samples were positive in both techniques, 82 were negative, 1 was culture-positive with a negative FA-PNEU result, and 9 were FA-PNEU-positive with negative culture. The two bacteria most frequently detected by the FA-PNEU were Staphylococcus aureus (37.5%) and Streptococcus agalactiae (20%), and those detected by culture were Staphylococcus aureus (34.78%) and Klebsiella pneumoniae (26.08%). The overall concordance was 90.1%, and when stratified by microorganism, it was between 92.7 and 100%. The positive predictive value (PPV) was between 50 and 100% and were lower for Enterobacter cloacae and Staphylococcus aureus. The negative predictive value (NPV) was high (between 99.1 and 100%); MecA/C/MREJ had a specificity of 94.55% and an NPV of 100%. The inflammatory response tests showed no significant differences between patients whose samples were positive and negative for both techniques. Sixty-one patients (55.45%) received at least one dose of empirical antibiotics.

Conclusions

The overall concordance was 90.1%, and it was between 92.7% and 100% when stratified by microorganisms. The positive predictive value was between 50 and 100%, with a very high NPV.

Etiology and the challenge of diagnostic testing of community-acquired pneumonia in children and adolescents

Background

Pneumonia is the leading cause of mortality in pediatric population. The etiology of pneumonia in this population is variable and changes according to age and disease severity and where the study is conducted. Our aim was to determine the etiology of community-acquired pneumonia (CAP) in children aged 1 month to 17 years admitted to 13 Colombian hospitals.

Methods

Prospective cohort study. Hospitalized children with radiologically confirmed CAP and ≤ 15 days of symptoms were included and followed together with a control group. Induced sputum (IS) was submitted for stains and cultures for pyogenic bacteria and Mycobacterium tuberculosis, and multiplex PCR (mPCR) for bacteria and viruses; urinary antigens for pneumococcus and Legionella pneumophila; nasopharyngeal swabs for viruses, and paired serology for atypical bacteria and viruses. Additional cultures were taken at the discretion of primary care pediatricians.

Results

Among 525 children with CAP, 71.6% had non-severe pneumonia; 24.8% severe and 3.6% very severe pneumonia, and no fatal cases. At least one microorganism was identified in 84% of children and 61% were of mixed etiology; 72% had at least one respiratory virus, 28% pyogenic bacteria and 21% atypical bacteria. Respiratory syncytial virus, Parainfluenza, Rhinovirus, Influenza, Mycoplasma pneumoniae, Adenovirus and Streptococcus pneumoniae were the most common etiologies of CAP. Respiratory syncytial virus was more frequent in children under 2 years and in severe pneumonia. Tuberculosis was diagnosed in 2.3% of children. IS was the most useful specimen to identify the etiology (33.6%), and blood cultures were positive in 3.6%. The concordance between all available diagnostic tests was low. A high percentage of healthy children were colonized by S. pneumoniae and Haemophilus influenzae, or were infected by Parainfluenza, Rhinovirus, Influenza and Adenovirus.

Conclusions

Respiratory viruses are the most frequent etiology of CAP in children and adolescents, in particular in those under 5 years. This study shows the challenges in making an etiologic diagnosis of CAP in pediatric population because of the poor concordance between tests and the high percentage of multiple microorganisms in healthy children. IS is useful for CAP diagnosis in pediatric population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03235-z.

Surveillance of Immunological Status after Vaccination by two Serological Assays based on SARS-CoV-2 Spike Protein

Purpose

Two serological assays, an Enzyme-Linked Immunosorbent Assay (ELISA) and a Lateral Flow Assay (LFA), have been developed based on the SARS-CoV-2 recombinant Receptor Binding Domain (RBD-ELISA) and the combination of Trimeric Spike (S) and Nucleoprotein (N), S-LFA and N-LFA, respectively, as candidate tools for both indirect measurement of virus circulation and assessment of infection and vaccine-induced immunity.

Methods & Materials

A total of 1272 human serum samples collected from volunteers (SARS-CoV-2 infected, non-infected or vaccinated) were evaluated by the two assays. For the RBD-ELISA, plates were coated with RBD, sera were added at 1/5 dilution and bound antibodies were detected with RBD labelled with Horseradish Peroxidase. For the LFA, two parallel strips were used: one for detection of N-specific antibodies (Hoste A. el al, 2020); and another one for detection of S-specific antibodies, using S both as capture and detector reagent. Twenty microliters of blood or ten microliters of serum were applied to each cassette and results were interpreted after ten minutes.

A seroneutralization assay was used as reference for the detection of neutralizing antibodies with RBD-ELISA and Reference sera (World Health Organization), for determination of the Limit of detection (LoD). MedCalc® 10 software was used for statistical analysis.

Results

The potential diagnostic application with sera from naturally infected and non-infected volunteers showed sensitivity, specificity and agreement (kappa) values of 95.1%, 99.0% and 0.94 respectively for RBD-ELISA; while 97.2%, 99.3% and 0.967 respectively for N-LFA; or 93.2% 98.3 %, 0.923, respectively for S-LFA. Serum samples from vaccinated individuals were analyzed for the specific detection of antibodies to the S protein: for vaccinated but non-infected individuals, sensitivity reached 97.3% after 15 days post-second vaccination dose whereas for previously infected people reached 100% after only 15 days post-first dose. The performance of RBD-ELISA showed good agreement with seroneutralization and excellent agreement with S-LFA (kappa 0.979).

Conclusion

The dual N/S LFA represents a valuable tool to detect SARS-CoV-2 infection due to its complementary information on N and S-specific antibody response. Furthermore, the S-LFA and RBD-ELISA are both proven to be able to determine the extent of antibody response after vaccination.

Acute Intrathoracic Tuberculosis in Children and Adolescents with Community-Acquired Pneumonia in an Area with an Intermediate Disease Burden

Tuberculosis (TB) in the pediatric population is a major challenge. Our objective was to describe the clinical and microbiological characteristics, radiological patterns, and treatment outcomes of children and adolescents (from 1 month to 17 years) with community-acquired pneumonia (CAP) caused by TB. We performed a prospective cohort study of a pediatric population between 1 month and 17 years of age and hospitalized in Medellín, Colombia, with the diagnosis of radiologically confirmed CAP that had ≤ 15 days of symptoms. The mycobacterial culture of induced sputum was used for the bacteriological confirmation; the history of TB contact, a tuberculin skin test, and clinical improvement with treatment were used to identify microbiologically negative TB cases. Among 499 children with CAP, TB was diagnosed in 12 (2.4%), of which 10 had less than 8 days of a cough, 10 had alveolar opacities, 9 were younger than 5 years old, and 2 had close contact with a TB patient. Among the TB cases, 50% (6) had microbiological confirmation, 8 had viral and/or bacterial confirmation, one patient had multidrug-resistant TB, and 10/12 had non-severe pneumonia. In countries with an intermediate TB burden, Mycobacterium tuberculosis should be included in the etiological differential diagnosis (as a cause or coinfection) of both pneumonia and severe CAP in the pediatric population.

Incidence and Risk Factors Associated with Latent Tuberculosis Infection and Pulmonary Tuberculosis among People Deprived of Liberty in Colombian Prisons

People deprived of liberty (PDL) are at high risk of acquiring Mycobacterium tuberculosis infection (latent tuberculosis infection [LTBI]) and progressing to active tuberculosis (TB). We sought to determine the incidence rates and factors associated with LTBI and active TB in Colombian prisons. Using information of four cohort studies, we included 240 PDL with two-step tuberculin skin test (TST) negative and followed them to evaluate TST conversion, as well as, 2,134 PDL that were investigated to rule out active TB (1,305 among people with lower respiratory symptoms of any duration, and 829 among people without respiratory symptoms and screened for LTBI). Latent tuberculosis infection incidence rate was 2,402.88 cases per 100,000 person-months (95% CI 1,364.62-4,231.10) in PDL with short incarceration at baseline, and 419.66 cases per 100,000 person-months (95% CI 225.80-779.95) in individuals with long incarceration at baseline (who were enrolled for the follow after at least 1 year of incarceration). The TB incidence rate among PDL with lower respiratory symptoms was 146.53 cases/100,000 person-months, and among PDL without respiratory symptoms screened for LTBI the incidence rate was 19.49 cases/100,000 person-months. History of Bacillus Calmette-Guerin vaccination decreased the risk of acquiring LTBI among PDL who were recently incarcerated. Female sex, smoked drugs, and current cigarette smoking were associated with an increased risk of developing active TB. This study shows that PDL have high risk for LTBI and active TB. It is important to perform LTBI testing at admission to prison, as well as regular follow-up to control TB in prisons.

Organosolv processing of vine shoots: Fractionation and conversion of hemicellulosic sugars into platform chemicals by microwave irradiation

Vine shoots were subjected to a mild aqueous extraction (to remove water-soluble extractives), and the extracted solids were reacted in catalyzed media (containing water and 1-butanol) to achieve the one-stage solubilization of lignin and hemicelluloses, yielding a cellulose-rich solid. Operating in a microwave-heated reactor under optimized conditions (190 °C in media containing 2% of catalyst and 52% 1-butanol), 67.8% lignin was dissolved, and solids containing 75% cellulose were obtained. Lignin was recovered from the reaction medium and characterized, whereas the hemicellulose-derived products present in the aqueous phase (obtained under conditions leading to maximum concentrations of 17.7 g pentoses/L) were converted into furfural at 64.6% molar yield by acidic processing in the presence of recycled 1-butanol.

Evidence for Succession and Putative Metabolic Roles of Fungi and Bacteria in the Farming Mutualism of the Ambrosia Beetle Xyleborus affinis

The bacterial and fungal community involved in ambrosia beetle fungiculture remains poorly studied compared to the famous fungus-farming ants and termites. Here we studied microbial community dynamics of laboratory nests, adults, and brood during the life cycle of the sugarcane shot hole borer, Xyleborus affinis We identified a total of 40 fungal and 428 bacterial operational taxonomic units (OTUs), from which only five fungi (a Raffaelea fungus and four ascomycete yeasts) and four bacterial genera (Stenotrophomonas, Enterobacter, Burkholderia, and Ochrobactrum) can be considered the core community playing the most relevant symbiotic role. Both the fungal and bacterial populations varied significantly during the beetle's life cycle. While the ascomycete yeasts were the main colonizers of the gallery early on, the Raffaelea and other filamentous fungi appeared after day 10, at the time when larval hatching happened. Regarding bacteria, Stenotrophomonas and Enterobacter dominated overall but decreased in foundresses and brood with age. Finally, inferred analyses of the putative metabolic capabilities of the bacterial microbiome revealed that they are involved in (i) degradation of fungal and plant polymers, (ii) fixation of atmospheric nitrogen, and (iii) essential amino acid, cofactor, and vitamin provisioning. Overall, our results suggest that yeasts and bacteria are more strongly involved in supporting the beetle-fungus farming symbiosis than previously thought.IMPORTANCE Ambrosia beetles farm their own food fungi within tunnel systems in wood and are among the three insect lineages performing agriculture (the others are fungus-farming ants and termites). In ambrosia beetles, primary ambrosia fungus cultivars have been regarded essential, whereas other microbes have been more or less ignored. Our KEGG analyses suggest so far unknown roles of yeasts and bacterial symbionts, by preparing the tunnel walls for the primary ambrosia fungi. This preparation includes enzymatic degradation of wood, essential amino acid production, and nitrogen fixation. The latter is especially exciting because if it turns out to be present in vivo in ambrosia beetles, all farming animals (including humans) are dependent on atmospheric nitrogen fertilization of their crops. As previous internal transcribed spacer (ITS) metabarcoding approaches failed on covering the primary ambrosia fungi, our 18S metabarcoding approach can also serve as a template for future studies on the ambrosia beetle-fungus symbiosis.

THU0347 CLINICAL DESCRIPTION OF A COHORT OF PATIENTS WITH SCLEROTIC-TYPE CHRONIC GRAFT-VERSUS-HOST DISEASE TREATED IN A MULTIDISCIPLINARY PRACTICE

Background:

Graft versus host disease is the most frequent complication after allogeneic transplantation of hematopoietic progenitors. Its chronic form usually involves a multisystemic syndrome that reflects a complex immune response with varying degrees of inflammation, immune dysregulation and fibrosis, responsible for the characteristic clinical manifestations of the disease. Joint, muscular and fascial involvement represents one of the areas, often unnoticed or poorly evaluated, that negatively impacts the physical function and quality of life of these patients.

Objectives:

Describe the presence of musculoskeletal manifestations and their clinical characteristics in patients with chronic GVHD (cGVHD) evaluated in a multidisciplinary consultation

Methods:

Descriptive and retrospective observational study to detail the initial presence and during the follow-up of diagnostic and nonspecific musculoskeletal manifestations of cGVHD in a cohort of 103 patients included in the database. The clinical characteristics of 68 patients with a defined diagnosis of sclerotic cGVHD are described. Demographic variables are collected along with clinical conditions about transplant and in a systematic way the assessment according to diagnostic criteria of the American National Institute of Health 2015 highlighting: range of motion scale and photographic range of motion (P-ROM) scale in shoulders, elbows, hands and ankles; and laboratory data: presence of eosinophilia and autoantibodies. Descriptive and frequency statistical analysis was done using Microsoft Office Excel 2007.

Results:

Sixty-eight(66%)patients meet diagnostic criteria for sclerotic cGVHD during follow-up. Forty-five(66.2%) women and 23(33.8%) men, with a mean age of 54.5 years (range 10-78), Acute myeloid leukemia was the reason for transplant in 20(29, 4%) followed by non-Hodgkin lymphoma in 15 (16.2%). In 40(58.7%) patients it was performed from a related donor and with reduced intensity conditioning in 43(63.2%). Only in one patient the source of hematopoietic progenitors was bone marrow (rest peripheral blood). The average time from transplant to the first visit was 29.5 months (range 4 -168). Twelve(17.64%) patients presented isolated joint/fascial involvement without objective skin involvement (Table 1)

Table 1.

Clinical features of the sclerotic joint/fascial chronic GVHD cohort (N= 68)

Unspecific musculoskeletal symptoms:46 (67.6%)-Artromyalgia39(57.3%)-Edema13(19%)-Stiffness 4(5.8%)Fasciitis/contractures28(41.2%)/43(63,2%)Restricted ROM1-Mild/Moderate/Severe34(50%)/14(20.2%)/4(5.8%)Impaired mobility-Shoulders26(38.2%)-Elbows21(30.8%)-Wrist/fingers29(42.6%)-Ankles21(30.6%)Sclerodermatous involvement-Superficial /deep 6(8.8%)/7(10.3%)-Mixed (sclerodermiform + lichenoid)20(29.4%)-Overlapping skin sclerosis13(19.2)NIH1Global Score-Mild/Moderate/Severe25(36.7%)/7(10.3%)/1(1.5%)Eosinophilia21 (30.8%)Autoantibodies14 (20.6%)

1ROM (range of motion)2NIH: National Institute of Health

Conclusion:

Joint involvement secondary to sclerosis is very common in our cohort, mainly of the dorsal wrist flexion with deleterious repercussion on physical function. It needs to be recognized and evaluated early with validated scales. The search for new biomarkers associated with fibrosis, the use of advanced imaging techniques and the multidisciplinary approach can help improve the prognosis of patients with cGVHD.

References:

[1]Jagasia MH,Blood Marrow Transplant. 2015;21(3):389–40

Disclosure of Interests:

None declared

Delays in HIV and TB diagnosis and treatment initiation in co-infected patients in Colombia

We investigated the delays in the diagnosis of tuberculosis and/or HIV, their treatment initiation, and factors associated with each delay. All drug-susceptible tuberculosis cases diagnosed in 2014 and 2015 in Colombia, with a confirmed diagnosis of HIV were included. A total of 1909 patients were registered with tuberculosis/HIV co-infection. Seventy-nine percent of patients were men, 50% had sputum smear-negative tuberculosis, culture was done in 50% of cases, 68.5% had <200 CD4 cell count at diagnosis, and 35% had concurrent tuberculosis/HIV diagnosis. Delays in the tuberculosis diagnosis were identified in 54.8% of the patients, and delays in tuberculosis and HIV treatment initiation in 41.8% and 27.4%, respectively. The risk factors associated with delay in tuberculosis diagnosis were age between 15–34 and ≥45 years, and those patients who received tuberculin skin test. The risk factor associated with antiretroviral therapy initiation delay was previously-treated tuberculosis patients after failure. It is necessary to implement strategies for early detection and treatment initiation of HIV and to use rapid test for tuberculosis diagnosis in this population.

Is tuberculosis elimination a feasible goal in Colombia by 2050?

Colombia has an underreporting of 30% of the total cases, according to World Health Organization (WHO) estimations. In 2016, successful tuberculosis (TB) treatment rate was 70%, and the mortality rate ranged between 3.5% and 10%. In 2015, Colombia adopted and adapted the End TB strategy and set a target of 50% reduction in incidence and mortality by 2035 compared with 2015. The aims of this study were: To evaluate whether Colombia will be able to achieve the goals of TB incidence and mortality by 2050, using the current strategies; and whether the implementation of new screening, diagnosis and TB treatment strategies will allow to achieve those WHO targets. An ecological study was conducted using TB case-notification, successful treatment and mortality rates from the last 8 years (2009-17). System dynamics analysis was performed using simulated scenarios: (1) continuation with the same trends following the trajectory of the last 8 years (Status quo) and (2) modification of the targets between 2017 through 2050, assuming the implementation of multimodal strategies to increase the screening, to improve the early diagnosis and to improve the treatment adherence. Following the current strategies, it is projected that Colombia will not achieve the End TB strategy targets. Achieving the goal of TB incidence of 10/100 000 by 2050 will only be possible by implementing combined strategies for increasing screening of people with respiratory symptoms, improving access to rapid diagnostic tests and improving treatment adherence. Therefore, it is necessary to design and implement simultaneous strategies according to the population needs and resources, in order to stride towards the End TB targets.

Homelessness and HIV: A Combination Predictive of Poor Tuberculosis Treatment Outcomes and in Need of Innovative Strategies to Improve Treatment Completion

Antioquia Department is the state with the highest burden of tuberculosis (TB) in Colombia. Our aim was to determine the risk factors associated with unsuccessful TB treatment in HIV-seropositive and homeless persons, compared with non-HIV-infected and non-homeless persons with TB. We conducted a retrospective cohort study using observational, routinely collected health data from all drug-susceptible TB cases in homeless and/or HIV-seropositive individuals in Antioquia from 2014 to 2016. Unsuccessful TB treatment was defined as individuals having been lost to follow-up, having died, or treatment failure occurrence during the study period. Successful treatment was defined as cure of TB or treatment completion according to the WHO definitions. We identified 544 homeless persons with TB (432 HIV- and 112 HIV+), 835 HIV+ persons with TB and non-homeless, and 5,086 HIV-/non-homeless people with TB. Unsuccessful treatment rates were 19.3% in HIV-/non-homeless persons, 37.4% in non-homeless HIV+ patients, 61.5% in homeless HIV- patients, and 70.3% in homeless HIV+ patients; all rates fall below End TB strategy targets. More than 50% of homeless patients were lost to follow-up. Risk factors associated with unsuccessful treatment were HIV seropositivity, homelessness, male gender, age ≥ 25 years, noncontributory-type health insurance, TB diagnosis made during hospitalization, and previous treatment for TB. These results highlight the challenge of treating TB in the homeless population. These findings should put an onus on TB programs, governments, clinicians, and others involved in the collaborative care of TB patients to pursue innovative strategies to improve treatment success in this population.

[Factors associated with completion of isoniazid preventive therapy in children in Quito, Ecuador (2014-2016 and 2018)Fatores associados à adesão à terapia preventiva com isoniazida em crianças de Quito, Equador (2014-2016 e 2018)]

Objetivo.

Conocer el porcentaje de cumplimiento de la terapia preventiva con isoniacida (TPI) en los establecimientos de salud de Quito, Ecuador y sus factores asociados en los niños menores de 5 años.

Métodos.

Investigación operativa con diseño de cohorte, en la que se obtuvo datos de informes y tarjetas de administración de tratamiento de los niños en TPI de los años 2014 al 2016 y de encuestas ad hoc aplicadas a cuidadores de los niños que recibieron TPI durante el año 2018.

Resultados.

Los niños menores de 5 años correspondieron a 29,3% del total de los contactos de los casos índices; 73% cumplieron TPI y 88,9% completaron al menos 6 meses de terapia. Se encontró asociación con la carga bacilar del caso índice, con la condición de pertenecer a un determinado distrito y su año de inicio. Se realizaron encuestas a 9 personas, funcionarios de los establecimientos salud y a 9 tutores de los niños; se registraron respuestas diversas sobre el agente causal de la tuberculosis, su transmisión y las características de la terapia preventiva.

Conclusiones.

La mayoría de los niños menores de 5 años que iniciaron TPI cumplieron con al menos 80% de las dosis prescritas, con determinadas asociaciones y percepciones en los cuidadores. En este contexto, surge la necesidad de realizar nuevas investigaciones operativas, para indagar más ampliamente sobre la adherencia y sobre los conocimientos, actitudes y prácticas de los profesionales de salud, los afectados por tuberculosis y su entorno.

Risk of infection and disease progression in children exposed to tuberculosis at home, Colombia

Aim:

To assess the risk of tuberculosis (infection and disease) in children less than 15 years’ old who are household contacts of pulmonary tuberculosis patients in three Colombian cities (Medellín, Cali, and Popayán).

Methods:

A cohort of 1,040 children household contacts of 380 adults with smear-positive pulmonary tuberculosis was followed up for 24 months. Study period 2005-2009.

Results:

Tuberculin skin test was positive (≥10 mm) in 43.7% (95% CI: 39.2-48.2). Tuberculin skin test positivity was associated with age 10-14 years (Prevalence Ratio -PR= 1.43, 95% CI: 1.1-1.9), having a BCG vaccine scar (PR= 1.52, 95% CI: 1.1-2.1), underweight, closer proximity to the index case and exposure time >3 months. The annual risk of infection (tuberculin skin test induration increase of 6 mm or more per year) was 17% (95% CI: 11.8-22.2) and was associated with a bacillary load of the adult index case (Relative Risk -RR= 2.12, 95% CI: 1.0-4.3). The incidence rate of active tuberculosis was 12.4 cases per 1,000 persons-year. Children <5 years without BCG vaccine scar had a greater risk of developing active disease (Hazard Ratio -HR= 6.00, 95% CI: 1.3-28.3) than those with scar (HR= 1.33, 95% CI: 0.5-3.4). The risk of developing active tuberculosis augmented along with the increase from initial tuberculin skin test (tuberculin skin test 5-9 mm HR= 8.55, 95% CI: 2.5-29.2; tuberculin skin test ≥10 mm HR= 8.16, 95% CI: 2.0-32.9).

Conclusions:

There is a need for prompt interruption of adult-to-children tuberculosis transmission within households. Conducting proper contact investigation and offering chemoprophylaxis to infected children could reduce tuberculosis transmission.

[Loss to follow-up in patients treated for multidrug-resistant tuberculosis in EcuadorA Perda de seguimento de pacientes tratados para tuberculose multirresistente a medicamentos no Equador]

OBJECTIVE

Determine the incidence of loss to follow-up (LTFU) in patients treated for rifampicin-resistant tuberculosis (RR-TB) or multidrug-resistant tuberculosis (RR/MDR-TB), and the factors associated with this discharge status in Ecuador.

METHODS

Retrospective cohort study of patients with RR/MDR-TB who followed the World Health Organization's 18-24-month treatment regimen in 2014 and 2015, as reported by the Ministry of Health of Ecuador. The incidence of LTFU was determined, and clinical and epidemiological manifestations of cases discharged as LTFU were compared with those discharged as successfully treated. Survival was analyzed with Cox regression in order to evaluate factors associated with LTFU.

RESULTS

Of 328 cases, 270 (82.3%) were analyzed because they had a reported discharge status. Discharge as LTFU accounted for 39.6% of cases, and as successfully treated, 50.4%. The risk factors associated with LTFU were: previous discharge as LTFU in a previous TB episode [hazard ratio (HR): 2.96 (1.53-5.73), P < 0.001]; addiction to alcohol or drugs [HR: 2.82 (1.10-7.23), P = 0.031]; and having an Xpert® diagnosis (TB-RR) [HR: 1.53 (1.0-2.35), P = 0.048]. Of the total LTFU, 43% occurred after nine months of treatment.

CONCLUSION

The incidence of LTFU in patients with RR/MDR-TB in Ecuador is above the average for the Region of the Americas. The three identified factors support implementation of shorter regimens and patient-centered care, in line with the End TB Strategy.

[Factors associated with tuberculosis mortality in Paraguay, 2015-2016Fatores associados à mortalidade por tuberculose no Paraguai, 2015-2016]

OBJECTIVE

To describe the socio-demographic and clinical-epidemiological characteristics and to determine the factors associated with the mortality of people diagnosed with tuberculosis (TB) in Paraguay.

METHODS

Operational research with a retrospective cohort design of cases diagnosed with TB in Paraguay between 2015-2016. The database of the National Tuberculosis Control Program was used. Chi-square and relative risk (RR) tests with a 95% confidence interval (95% CI) were used to determine the factors associated with mortality; in addition, a robust Poisson multiple regression model was adjusted. A significance level of 5% was used.

RESULTS

Five hundred and forty-one cases of TB were studied, of which 11.5% died. The factors increasing the risk of death were male sex (RR 1.26; 95% CI 1.1-1.50), infection with human immunodeficiency virus (RR 4.78; 95% CI 4.04-5.65) and chronic obstructive pulmonary disease (RR 1.70; 95% CI 1.19-2.42). Being deprived of one's liberty was a protective factor (RR 0.37; 95% CI 0.24-0.61).

CONCLUSIONS

The highest risk of death is presented by men and people with TB/HIV coinfection and the lowest risk is presented by people deprived of liberty. There is a need to improve diagnosis and follow-up of TB cases, with effective implementation of directly observed treatment (DOTS) and timely management of associated diseases such as HIV and chronic obstructive pulmonary disease.

[Prevalence of comorbidity tuberculosis and diabetes mellitus in Paraguay, 2016 and 2017Prevalência de comorbidade tuberculose-diabetes mellitus no Paraguai, 2016 e 2017]

Objetivo.

Estimar la prevalencia nacional y regional de la comorbilidad tuberculosis (TB) y diabetes mellitus (DM) e identificar los factores asociados con esta comorbilidad en Paraguay.

Métodos.

Estudio transversal en pacientes con TB notificada en 2016 y 2017 y registrados en la base de datos del Programa Nacional de Control de la TB. La prevalencia de DM, definida por autonotificación, se estimó en pacientes con TB. Para conocer los factores asociados con la comorbilidad TB-DM se empleó un modelo multivariante de regresión binomial para ajustar las razones de prevalencia (RP) según los errores estándar por el clúster de región sanitaria.

Resultados.

Entre 2016 y 2017 se notificaron 5 315 casos de TB. La prevalencia de la comorbilidad TB-DM fue 6,3% en 2016, 6,0% en 2017 y 6,2% en ambos años. Fue más alta en Itapúa (9,2%), Alto Paraguay (8,0%), Alto Paraná (7,5%), Central (7,4%) y Asunción (7,2%). La mediana de edad de personas con DM fue más alta que la de las que no tenían DM (55 y 33 años; P < 0,001). Tener una edad mayor de 45 años (RP = 18,3), el sexo femenino, antecedente de hipertensión arterial (HTA) (RP = 2,17), baciloscopía de diagnóstico de tres cruces (RP 1,98), y antecedente de enfermedad pulmonar obstructiva crónica (EPOC) (RP 1,68) estuvieron asociados con mayor comorbilidad. En cambio, se asociaron con menor comorbilidad pertenecer a la población indígena (RP = 0,26), la infección por el virus de la inmunodeficiencia humana (RP = 0,44), historia de adicción a drogas (RP = 0,49), el sexo masculino (RP = 0,64), y la TB extrapulmonar (RP = 0,75).

Conclusiones.

La prevalencia de la comorbilidad de TB y DM en Paraguay, por autonotificación, fue 6,2% en el periodo 2016-2017 y varió entre las regiones sanitarias. La edad, una alta carga bacilar al diagnóstico y la comorbilidad con HTA y EPOC se asociaron a una mayor comorbilidad. Estos hallazgos permitirán priorizar grupos de población para aumentar rendimiento del cribado, diagnóstico, tratamiento y prevención de la comorbilidad TB-DM en Paraguay.

Guards in Prisons: A Risk Group for Latent Tuberculosis Infection

To determine the prevalence and incidence of LTBI among prison guards and to the risk factors associated with infection. Two male prisons in Medellín and Itaguí, Colombia. A cohort study was conducted in adult prison guards that consented to participate. Exclusion criteria included: previous or current active TB, or conditions that preclude TST administration. We screened 194 guards and completed 155 TST administrations. The prevalence of LTBI was 55.8% in prison one, and 39.1% in prison two. The risk factors associated with LTBI diagnosis included drug use at least once in a lifetime (PR: 1.75; 95% CI 1.42-2.15) and male sex (PR: 2.16; 95% CI 1.01-4.62). The cumulative incidence of TST conversion over 6 months was 3.2%. All conversions occurred in prison 1. Our findings suggest an occupational risk for LTBI prevalence and incidence among guards (different prevalence and incidence according to the prison they work).

Inflammatory Cell Differentiation and Chemotaxis and Extracellular Tissue Repair Markers Are Correlated with Pulmonary Dysfunction in HIV Infected Individuals Presenting with Community-Acquired Pneumonia

Prior studies have shown that HIV patients develop permanent pulmonary dysfunction following an episode of community-acquired pneumonia (CAP). However, the mechanism causing pulmonary dysfunction remains an enigma. HIV patients experience chronic inflammation. We hypothesized that CAP exacerbates inflammation in HIV patients resulting in an accelerated decline in lung function. A prospective cohort pilot study enrolled HIV patients hospitalized in Medellin, Colombia, with a diagnosis of CAP. Sixteen patients were eligible for the study; they were split into 2 groups: HIV and HIV+CAP. Plasma, sputum, and pulmonary function test (PFT) measurements were retrieved within 48 h of hospital admission and at 1 month follow-up. The concentrations of 13 molecules and PFT values were compared between the 2 cohorts. The HIV+CAP group had lower lung function compared to the HIV group; forced vital capacity (FVC)% predicted and forced expiratory volume in 1 s (FEV₁)% predicted decreased, while FEV₁/FVC remained constant. APRIL, BAFF, CCL3, and TIMP-1 correlated negatively with FVC% predicted and FEV₁% predicted; the relationships however were moderate in strength. Furthermore, the concentrations of BAFF, CCL3, and TIMP-1 were statistically significant between the 2 groups (P ≤ 0.05). Our results indicate that HIV patients with CAP have a different inflammatory pattern and lower lung function compared to HIV patients without CAP. BAFF, CCL3, and TIMP-1 were abnormally elevated in HIV patients with CAP. Future studies with larger cohorts are required to verify these results. In addition, further investigation is required to determine if BAFF, CCL3, and TIMP-1 play a role in the process causing pulmonary dysfunction.

Myths and realities about knowledge, attitudes and practices of household contacts of tuberculosis patients

SETTING

Five Colombian cities: Villavicencio, Pereira, Cucuta, Bucaramanga and Bosa.

OBJECTIVE

To describe the knowledge, attitudes and practices related to tuberculosis (TB) in household contacts (HHCs) of TB patients.

METHODS

A cross-sectional study was conducted. The estimated sample size required was 855. The World Health Organization guide 'Advocacy, communication and social mobilization for TB control: a guide to developing knowledge, attitude and practice surveys' was translated into Spanish and adapted to the dialect of each city. HHCs were invited to participate in the study and included if they agreed.

RESULTS

We interviewed 878 HHCs. Most of them knew that TB was transmitted by airborne droplets; however, 52.2% also said that TB could be transferred from one person to another by sharing plates or clothes or shaking hands. Fifty-five per cent of HHCs acquired TB-related information from health care workers, and 44% from family members and friends. Fear was the main reaction reported by HHCs when they were informed of a TB diagnosis (60%). Eighty-five per cent of HHCs answered that the community rejects or avoids TB cases.

CONCLUSION

There are significant gaps in the knowledge about TB and the stigmatisation associated with it. Educational strategies should be designed together with the community to demystify many misconceptions about TB.

Factors associated with delays in pulmonary tuberculosis diagnosis and treatment initiation in Cali, Colombia

Objective.

To determine factors associated with delays in pulmonary tuberculosis diagnosis and treatment initiation in the city of Cali, Colombia.

Methods.

This was a retrospective cohort study of cases of tuberculosis (TB) reported in the TB control program of Cali between January and December 2016. The information was collected from the databases of the TB control program, individual treatment cards, and clinical histories. The variables considered were sociodemographic factors, clinical factors, substance use, and performance of the health service.

Results.

A total of 623 cases were identified, of which 57.0% were male. The median age was 42 years (interquartile range (IQR): 27–60). The median time from onset of symptoms to TB diagnosis was 57 days (IQR: 21–117), and from onset of symptoms to TB treatment initiation was 72 days (IQR: 35–145). A factor associated with longer time from the onset of symptoms to TB treatment was being a previously treated TB patient (coefficient: 123.8 days, 95% confidence interval (CI): 48.3 to 199.3). In contrast, being incarcerated was a protective factor for earlier TB treatment initiation (coefficient: -57.3 days; 95% CI: -92.4 to -22.3).

Conclusions.

Our results provide important information concerning risk factors that are associated with delays in the diagnosis and treatment of tuberculosis, and that are subject to future interventions. Health insurance program managers must work together with health care providers on issues that include patient care, health promotion, and updating TB protocols and standards.

The association of parental and offspring educational attainment with systolic blood pressure, fasting blood glucose and waist circumference in Latino adults

Objective

The objective of the study is to evaluate the association of intergenerational educational attainment with cardiovascular disease (CVD) risk factors among US Latinos.

Methods

We used cross‐sectional data from the Niños Lifestyle and Diabetes Study, an offspring cohort of middle‐aged Mexican‐Americans whose parents participated in the Sacramento Latino Study on Aging. We collected educational attainment, demographic and health behaviours and measured systolic blood pressure (SBP), fasting glucose and waist circumference. We evaluated the association of parental, offspring and a combined parent–offspring education variable with each CVD risk factor using multivariable regression.

Results

Higher parental education was associated only with smaller offspring waist circumference. In contrast, higher offspring education was associated with lower SBP, fasting glucose and smaller waist circumference. Adjustment for parental health behaviours modestly attenuated these offspring associations, whereas adjustment for offspring health behaviours and income attenuated the associations of offspring education with offspring SBP and fasting glucose but not smaller waist circumference, even among offspring with low parental education.

Conclusions

Higher offspring education is associated with lower levels of CVD risk factors in adulthood, despite intergenerational exposure to low parental education.

2266. Persistent Inflammation in HIV Patients With Community-Acquired Pneumonia and Its Correlation With Lung Injury

Background

HIV patients face higher rates of morbidity compared with the general population, largely due to the earlier development of age related diseases (cardiovascular, kidney, and liver disease). While it is likely that chronic immune activation and inflammation are the main contributors to this process, it’s relation to lung injury in HIV remains unknown. Despite restoration of systemic immune function following Antiretroviral Therapy, the risk for lower respiratory tract infection remain elevated in the HIV population. The objective of the study was to assess the relationship between pulmonary inflammation and lung injury.

Methods

A prospective cohort study was performed, participants include patients hospitalized in Hospital Universitario San Vicente Fundación and Clínica SOMA, in Colombia. Patients were eligible if they were over the age of 18 and had a documented HIV infection or if they have HIV with newly diagnosed community acquired pneumonia (CAP). The main exclusion criteria were chronic lung disease and immunosuppression that is not due to HIV. Patients belonged to two groups: HIV and HIV + CAP. Plasma, sputum samples and pulmonary function test measurements (PFT) were retrieved within 48 hours of hospital admission and at one month follow-up. The concentrations of 13 biomarkers were measured and correlated with PFT values, followed by a comparison between the two groups.

Results

Principle Component Analysis revealed that CCL3, CCL4, BAFF, APRIL, and TIMP-1 accounts for the majority of the variation between the two groups. Furthermore, Kruskal–Wallis testing demonstrates that BAFF and CCL3 are elevated in the HIV + CAP group, compared with the HIV group (P < 0.005). Other markers of bacterial translocation and monocyte activation did not differ between these groups. FVC and FEV₁ measurements are lower in the HIV + CAP group compared with the HIV group, while FEV₁/FVC remain constant.

Conclusion

The results of this study identify a unique constellation of biomarkers in HIV patients with CAP, this constellation of biomarkers consists of pro-inflammatory cytokines and regulators of extracellular matrix remodeling, hinting at the occurrence of an inflammatory and tissue injuring process in the lungs. This is supported by the restrictive ventilation pattern seen in this group of patients.

Disclosures

All authors: No reported disclosures.

AdNut study: effectiveness of a high calorie and protein oral nutritional supplement with β-hydroxy-β-methylbutyrate in an older malnourished population in usual clinical practice

Objective

To evaluate the effectiveness of a high calorie and protein, β-hydroxy-β-methylbutyrate containing oral nutritional supplement (HP-HMB-ONS), on nutritional status, activities of daily living and quality of life (QoL) in old malnourished subjects.

Methods

We conducted an observational, prospective, open label, multicenter study. Participants were > 65 years, undernourished or at nutritional risk [Nutrition Risk Score (NRS) ≥ 3] and had been included on an ONS (HP-HMB-ONS twice daily for 12 weeks) per standard of care. Visits at baseline (V1), 6 weeks (V2) and 12 weeks (V3) were performed. The primary endpoints were gain of body weight, change in body mass index (BMI) and NRS 2002 index. Data from QoL (EQ-5D-3L) and activities of daily living (Katz index) were also collected.

Results

A total of 235 participants were included in the study. Of these 148 took at least a 75% of the HP-HMB-ONS and were included in the analysis (per protocol); median age was 80.0 (SD:8.3) years, 65.5% (n = 97) were female, 67.6% (n = 100) had 2 or more diseases. At V3, a statistically significant increase in weight (2.1 kg; SD: 3.8) (p < 0.001) and BMI (0.8 kg/m²; SD: 1.45) were found compared to V1, whereas NRS 2002 values decreased by 0.9 (SD: 1.2). A significant (p < 0.001) improvement in Katz index (mean change = 0.3; SD:1.4) and EQ-5D scoring (mean change = 0.5; SD:1.9) compared to V1, were also reported.

Conclusions

The results suggest that administration of a HP-HMB-ONS improve the nutritional status and may led to a significant improvement in patients' activities of daily living and QoL, independent of baseline BMI.

Strongyloidiasis in humans: diagnostic efficacy of four conventional methods and real-time polymerase chain reaction

INTRODUCTION

Strongyloides stercoralis is an intestinal parasitic nematode that causes hyperinfection and/or a dissemination syndrome in hosts, which is often difficult to diagnose. This study aims to compare the diagnostic efficacy of four conventional methods used to diagnose strongyloidiasis with real-time polymerase chain reaction (qPCR) to detect S. stercoralis in fecal samples.

METHODS

We analyzed 143 fecal samples collected from Colombian regions with varying degrees of risk for intestinal infections caused by S. stercoralis to assess the validity, performance, overall efficiency, and concordance of the qPCR using a direct stool test, modified Ritchie concentration technique, agar plate culture, and Harada-Mori technique as reference tests.

RESULTS

While four fecal samples were positive for S. stercoralis using conventional methods, 32 were positive via qPCR. The diagnostic sensitivity of the qPCR was 75% [95% confidence interval (CI): 20.07-100%], whereas its specificity, negative predictive value, negative likelihood ratio, and Youden's J index were 78.42% (95% CI: 71.22-85.62%), 99.09% (95% CI: 96.86-100%), 0.32 (95% CI: 0.06-1.74), and 0.53, respectively. In addition, the estimated kappa index between the qPCR and the conventional methods was 0.12 (95% CI: -0.020-0.26).

CONCLUSIONS

The diagnostic sensitivity of qPCR to detect strongyloidiasis is analogous to that of conventional parasitology methods, with an additional advantage of being capable of identifying the parasite DNA at low sample concentrations.

PPD-induced monocyte mitochondrial damage is associated with a protective effect to develop tuberculosis in BCG vaccinated individuals: A cohort study

Introduction

The mechanisms of mononuclear phagocyte death have been associated with the permissiveness and resistance to mycobacterial replication, but it remains unknown whether or not they help predict the risk of developing TB.

Objective

To describe the factors associated with the induction of monocyte mitochondrial and membrane damage in response to PPD as well as determine if this type of damage might predict the susceptibility of developing active tuberculosis in a cohort of household contacts (HHCs) from Medellin, Colombia from 2005 to 2008.

Methods

The prospective cohort study contains 2060 HHCs patients with pulmonary tuberculosis who were meticulously followed for two years. A survey of the socio-demographic, clinical, epidemiological factors and blood samples were collected. Mononuclear cell cultures were stimulated with or without PPD and the type of monocyte death was determined by the flow of cytometry, an indicator was also used for its analysis. Logistic regression was adjusted by the Generalized Estimations Equations and the survival was estimated with the Kaplan-Meier and Cox regression. Confidence intervals were used for estimating the association.

Results

1,859 out of 2,060 blood samples of the HHCs patients analyzed showed monocyte death. In response to PPD, 83.4% underwent mitochondrial damage while 50.9% had membrane damage. The membrane damage in response to PPD was higher in children under 4 years (OR: 1.57; (95% CI: 1.1 to 2.4) and the HHCs who slept regularly in the same household has an index case of (OR: 1.54; 95% CI: 1.0 to 2.3). After adjustment by age, comorbidities, nutritional status, proximity to index case and overcrowding, the risk of developing active TB among BCG vaccinated HHCs individuals with induction of mitochondrial damage was HR = 0.19 (95% CI: 0.1 to 0.5).

Conclusions

The induction of monocytes mitochondrial damage by PPD stimulation correlates with protection of TB disease development in BCG-vaccinated HHCs. This represents a potential tool to predict susceptibility of developing active disease in this population.

[Laparoscopic nephron-sparing surgery for Wilms tumor: description of two cases]

Surgical resection is the mainstay of treatment for Wilms tumor. The research progress of the large study groups worldwide has reduced mortality. However, searching to minimize morbidity, the minimally invasive approach has been applied in selected patients. This article describes two cases of Wilms tumor managed with laparoscopic nephron sparing surgery. The case 1 with Beckwith-Wiedemann syndrome and bilateral disease, and the case 2 non-syndromic unilateral. The approach was intraperitoneally, without intraoperative complications. The follow-up to 18 months (case 1) and six months (case 2) did not have recurrence or metastatic disease.

Cost-Effectiveness of Highly Sensitive Cardiac Troponin T to Rule Out Acute Rejection After Heart Transplantation

BACKGROUND

Endomyocardial biopsy (EMB) remains the gold standard for detecting acute rejection (AR) after heart transplantation (HTx). Non-invasive detection of AR thus far remains a challenge. Several studies have demonstrated that highly sensitive cardiac troponin T (hs-cTnT) concentrations have a low positive predictive value for diagnosing AR. Nevertheless, hs-cTnT proved to be useful for ruling out AR after HTx. An hs-cTnT concentration <17 ng/L, a value close to that used for rule-in or rule-out myocardial infarction, was associated with a 100% negative predictive value of AR. However, the cost-effectiveness of a strategy with the use of hs-cTnT for ruling out AR in HTx patients remains to be proven.

METHODS

The cost-effectiveness of hs-cTnT determination for ruling out AR was assessed, comparing the costs of hs-cTnT measurements in 305 blood samples obtained at the time of EMB. Eighteen samples were excluded because the EMB was not assessable.

RESULTS

Hs-cTnT determination cost 16.00€ per sample, whereas EMB cost 1752.00€ per biopsy; cost estimations included direct and indirect (30%) charges. Thirty-nine (13.6%) of the 287 blood samples presented hs-cTnT concentrations <17 ng/L; in none of them was an AR >2R degree found in the EMB. The cost of the assessment in the 287 blood samples and biopsies was of 4592.00€ for hs-cTnT and 502,824.00€ for EMB. Hs-cTnT systematic measurement would have avoided 39 EMB, with a saving of 68,328.00€, which represents the 13.5% of the total budget expended in these cases.

CONCLUSIONS

The use of hs-cTnT values to rule out the need of EMB for AR diagnosis after HTx appears to be a cost-effective procedure.