Whole genome sequencing provides better delineation of transmission clusters in Mycobacterium tuberculosis than traditional methods. However, its ability to reveal individual transmission links ...within clusters is limited. Here, we used a 2-step approach based on Bayesian transmission reconstruction to (1) identify likely index and missing cases, (2) determine risk factors associated with transmitters, and (3) estimate when transmission happened.
We developed our transmission reconstruction method using genomic and epidemiological data from a population-based study from Valencia Region, Spain. Tuberculosis (TB) incidence during the study period was 8.4 cases per 100,000 people. While the study is ongoing, the sampling frame for this work includes notified TB cases between 1 January 2014 and 31 December 2016. We identified a total of 21 transmission clusters that fulfilled the criteria for analysis. These contained a total of 117 individuals diagnosed with active TB (109 with epidemiological data). Demographic characteristics of the study population were as follows: 80/109 (73%) individuals were Spanish-born, 76/109 (70%) individuals were men, and the mean age was 42.51 years (SD 18.46). We found that 66/109 (61%) TB patients were sputum positive at diagnosis, and 10/109 (9%) were HIV positive. We used the data to reveal individual transmission links, and to identify index cases, missing cases, likely transmitters, and associated transmission risk factors. Our Bayesian inference approach suggests that at least 60% of index cases are likely misidentified by local public health. Our data also suggest that factors associated with likely transmitters are different to those of simply being in a transmission cluster, highlighting the importance of differentiating between these 2 phenomena. Our data suggest that type 2 diabetes mellitus is a risk factor associated with being a transmitter (odds ratio 0.19 95% CI 0.02-1.10, p < 0.003). Finally, we used the most likely timing for transmission events to study when TB transmission occurred; we identified that 5/14 (35.7%) cases likely transmitted TB well before symptom onset, and these were largely sputum negative at diagnosis. Limited within-cluster diversity does not allow us to extrapolate our findings to the whole TB population in Valencia Region.
In this study, we found that index cases are often misidentified, with downstream consequences for epidemiological investigations because likely transmitters can be missed. Our findings regarding inferred transmission timing suggest that TB transmission can occur before patient symptom onset, suggesting also that TB transmits during sub-clinical disease. This result has direct implications for diagnosing TB and reducing transmission. Overall, we show that a transition to individual-based genomic epidemiology will likely close some of the knowledge gaps in TB transmission and may redirect efforts towards cost-effective contact investigations for improved TB control.
In most cases, severe asthma in children has an allergic etiology, but allergen-specific immunotherapy (AIT) is contraindicated.
This study aimed at analyzing the safety and efficacy of AIT in ...patients with severe asthma treated with omalizumab (OM).
A descriptive real-life study was carried out by reviewing medical records. Effectiveness was measured by the degree of control (CAN questionnaire), number of hospitalizations per year, number of exacerbations per year, and maintenance treatment and lung function (FEV1). Some adverse reactions occurred (AAI-EAACI-WAO guidelines).
The retrospective study included 29 patients up to 18 years of age with severe asthma with OM plus AIT treatment. AIT treatment was started in a cluster schedule when patients treated with OM achieved disease control. Before starting AIT, patients were treated with OM for 1 year for achieving asthmatic control. AIT to mites (51%),
(37.9%), or pollens (10.3%) was administered. After one year with OM plus AIT,statistically significant differences in CAN scores and FEV1 measures were observed (P < 0.001). No patients under treatment with OM plus AIT required hospital admission. During the clustering schedule, only 3/64 doses showed systemic adverse reactions. During the AIT maintenance treatment, 348 doses were administered, with no significant adverse reactions.
In this population-based study in children with severe asthma, the combined treatment with OM plus AIT was safe and effective. This strategy allows these pediatric patients to be safely treated with AIT.
A randomized, double-blind, and placebo-controlled study was conducted to assess the effect of dietary supplementation with high-rich docosahexaenoic acid (DHA) (Tridocosahexanoin-AOX
70%) at 50 ...mg/kg/day in pediatric patients with cystic fibrosis (CF) as compared with placebo. The duration of supplementation was 12 months. A total of 22 patients were included, with 11 in the DHA group and 11 in the placebo group. The mean age was 11.7 years. The outcome variables were pulmonary function, exacerbations, sputum cellularity, inflammatory biomarkers in sputum and peripheral blood, and anthropometric variables. In the DHA group, there was a significant increase in FVC (
= 0.004) and FVE
expressed in liters (
= 0.044) as compared with placebo, and a lower median number of exacerbations (1 vs. 2). Differences in sputum cellularity (predominantly neutrophilic), neutrophilic elastase, and sputum and serum concentrations of resolvin D1 (RvD1), interleukin (IL)-8 (IL-8), and tumor necrosis factor alpha (TNF-α) between the study groups were not found. Significant increases in weight and height were also observed among DHA-supplemented patients. The administration of the study product was safe and well tolerated. In summary, the use of a highly concentrated DHA supplement for 1 year as compared with placebo improved pulmonary function and reduced exacerbations in pediatric CF.
Transmission is a driver of tuberculosis (TB) epidemics in high-burden regions, with assumed negligible impact in low-burden areas. However, we still lack a full characterization of transmission ...dynamics in settings with similar and different burdens. Genomic epidemiology can greatly help to quantify transmission, but the lack of whole genome sequencing population-based studies has hampered its application. Here, we generate a population-based dataset from Valencia region and compare it with available datasets from different TB-burden settings to reveal transmission dynamics heterogeneity and its public health implications. We sequenced the whole genome of 785 Mycobacterium tuberculosis strains and linked genomes to patient epidemiological data. We use a pairwise distance clustering approach and phylodynamic methods to characterize transmission events over the last 150 years, in different TB-burden regions. Our results underscore significant differences in transmission between low-burden TB settings, i.e., clustering in Valencia region is higher (47.4%) than in Oxfordshire (27%), and similar to a high-burden area as Malawi (49.8%). By modeling times of the transmission links, we observed that settings with high transmission rate are associated with decades of uninterrupted transmission, irrespective of burden. Together, our results reveal that burden and transmission are not necessarily linked due to the role of past epidemics in the ongoing TB incidence, and highlight the need for in-depth characterization of transmission dynamics and specifically tailored TB control strategies.
We compared the bacterial microbiomes lodged in the bronchial tree, oropharynx and nose of patients with early stage cystic fibrosis (CF) not using chronic antibiotics, determining their ...relationships with lung function and exacerbation frequency. CF patients were enrolled in a cohort study during stability and were checked regularly over the following 9 months. Upper respiratory samples (sputum S, oropharyngeal swab OP and nasal washing N) were collected at the first visit and every 3 months. 16S rRNA gene amplification and sequencing was performed and analyzed with QIIME. Seventeen CF patients were enrolled (16.6 SD 9.6 years). Alpha-diversity of bacterial communities between samples was significantly higher in S than in OP (Shannon index median 4.6 IQR: 4.1–4.9 vs. 3.7 IQR: 3-1-4.1,
p
= 0.003/Chao 1 richness estimator median 97.75 IQR: 85.1–110.9 vs. 43.9 IQR: 31.7–59.9,
p
= 0.003) and beta-diversity analysis also showed significant differences in the microbial composition of both respiratory compartments (Adonis test of Bray Curtis dissimilarity matrix,
p
= 0.001). Dominant taxa were found at baseline in five patients (29.4%), who showed lower forced expiratory volume in the first second (FEV1%, mean 74.8 SD 19 vs. 97.2 SD 17.8,
p
= 0.035, Student
t
test). The
Staphylococcus
genus had low RAs in most samples (median 0.26% IQR 0.01–0.69%), but patients with RA > 0.26% of Staphylococcus in bronchial secretions suffered more exacerbations during follow-up (median 2 IQR 1–2.25 vs. 0 0–1,
p
= 0.026. Mann–Whitney U test), due to
S. aureus
in more than a half of the cases, microorganism that often persists as bronchial colonized in these patients (9/10 90% vs. 2/7 28.6%,
p
= 0.034, Fisher’s exact test). In conclusion, the bronchial microbiome had significantly higher diversity than the microbial flora lodged in the oropharynx in early stage CF. Although the RA of the
Staphylococcus
genus was low in bronchial secretions and did not reach a dominance pattern, slight overrepresentations of this genus was associated with higher exacerbation frequencies in these patients.
We characterized the fatty acid profiles in the erythrocyte membrane of pediatric patients with cystic fibrosis (CF) receiving highly concentrated docosahexaenoic acid (DHA) supplementation ...(Tridocosahexanoin-AOX
70%) at 50 mg/kg/day (
= 11) or matching placebo (
= 11) for 12 months. The mean age was 11.7 years. The DHA group showed a statistically significant improvement in n-3 polyunsaturated fatty acids (PUFAs), which was observed as early as 6 months and further increased at 12 months. Among the n-3 PUFAs, there was a significant increase in DHA and eicosapentaenoic acid (EPA). Additionally, a statistically significant decrease in n-6 PUFAs was found, primarily due to a decrease in arachidonic acid (AA) levels and elongase 5 activity. However, we did not observe any changes in linoleic acid levels. The long-term administration of DHA over one year was safe and well tolerated. In summary, the administration of a high-rich DHA supplement at a dose of 50 mg/kg/day for one year can correct erythrocyte AA/DHA imbalance and reduce fatty acid inflammatory markers. However, it is important to note that essential fatty acid alterations cannot be fully normalized with this treatment. These data provide timely information of essential fatty acid profile for future comparative research.
Objectives
Infants with cow's milk allergy (CMA) are in need of a substitute formula up to 2 years. The are three requisites for a substitute of milk in CMA: tolerability, nutritional adequacy, and ...cost‐effectiveness. We evaluate here the tolerability of a new amino acid–based infant formula for the management of CMA.
Methods
In a phase III/IV prospective, multicentre, open‐label, international study, infants and children with immunoglobulin E‐mediated CMA were exposed to a diagnostic double‐blinded, placebo‐controlled food challenge with a new amino acid formula by Blemil Plus Elemental using Neocate as the placebo. If tolerant to it, the study formula was integrated into the patients’ usual daily diet for 7 days. Efficacy on day 7 was assessed in terms of symptoms associated with CMA, amount of formula consumed, nutritional and energy intake, and anthropometric data.
Results
Thirty children (17 M and 13 F; median age, 1.58; range, 0.08‐12.83 years) completed the open challenge and were able to consume the study formula for at least 7 days. No signs or symptoms of allergic reactions were recorded among children assuming either the test or the control formula, with a lower 95% one‐sided confidence interval for the proportion of subjects who did not experience allergic reactions above 90%. Sixteen patient under the age of two continued with the optional extension phase.
Conclusions
The study formula meets the American Academy of Pediatric criteria for hypoallergenicity and is well tolerated in short‐term use. During optional phase, growth of the patients was not hindered by the study formula.
This study provides data on a new amino acid formula, documenting the hypoallergenicity of such a preparation in a cohort of children with milk allergy. These children are in need of a substitute formula especially up to 2 years. We designed a study in compliance with the rules and procedures indicated by the American Academy of Pediatric regarding studies on new special formulas to be included in the therapeutic options.
Background
Various studies have assessed omalizumab outcomes in the clinical practice setting but follow‐up and/or number of patients included were limited. We aim to describe the long‐term outcomes ...of pediatric patients with severe persistent allergic asthma receiving omalizumab in the largest real‐life cohort reported to date.
Methods
ANCHORS was a multicenter, observational, retrospective cohort study conducted in 25 Pediatric Allergy and Pulmonology units in Spain. We collected data of patients < 18 years and initiating omalizumab between 2006 and 2018, from the year prior to omalizumab initiation to discontinuation or last available follow‐up. The primary outcome was the evolution of the annual number of moderate‐to‐severe exacerbations compared with the baseline period.
Results
Of the 484 patients included, 101 (20.9%) reached 6 years of treatment. The mean ± standard deviation number of exacerbations decreased during the first year of treatment (7.9 ± 6.6 to 1.1 ± 2.0, P < .001) and remained likewise for up to 6 years. The other clinical parameters assessed also improved significantly during the first year and stabilized or continued to improve thereafter. The percentage of patients experiencing adverse events was consistently low, and the main reason for discontinuation was good disease evolution.
Conclusion
In this large, long‐term, observational study, moderate‐to‐severe exacerbations decreased significantly from the first year of treatment with omalizumab. The beneficial effect was maintained in the long term, along with a good safety profile. Our results position omalizumab as an effective long‐term treatment in pediatric patients with severe persistent allergic asthma.
Oral immunotherapy (OIT) is a promising approach to cow's milk and egg allergies, but reactions are frequent and some patients cannot be desensitized.
To evaluate long-term OIT outcomes with ...omalizumab (OMZ) in paediatric patients with severe egg and/or milk allergies.
This retrospective real-life study analysed findings in children with Immunoglobulin E-mediated allergy to cow's milk and/or hen eggs refractory to conventional OIT, who underwent OIT with OMZ in our department between 1 January 2010 and 31 December 2015.
In all, 41 patients were included (median age: 7 years; interquartile range IQR: 5.5-9.5); 26/41 (63.4%) underwent OIT for milk, 8/41 (19.5%) for egg and 7/41 (17.1%) for both. The median time between initiation of OMZ and OIT was 27 weeks (IQR: 22-33). Forty (97.56%) patients reached the maintenance phase (200 mL of cow's milk and 30 mL of raw egg or 1 cooked egg) in a median time of 27 weeks (IQR: 18-37). The median total time with OMZ was 117 weeks (IQR: 88-144). During the OMZ period, 2.44% (1/41) of patients presented anaphylaxis. After discontinuation of OMZ, 29.3% (12/41) presented anaphylaxis, 50% of them had a poor adherence to daily ingestion. One patient (2.44%) was diagnosed with eosinophilic esophagitis after 2 years of discontinuation of OMZ. Currently, after a median time of 9 years (IQR: 7-10) since the initiation of OMZ, 75.6% (31/41) are desensitized (27/31 without OMZ).
Omalizumab allows desensitisation of children with severe allergies to cow's milk and/or egg without developing severe reactions while receiving this treatment. However, discontinuation of OMZ leads to severe allergic reactions, and hence must be monitored carefully.
Relationship between the causal mechanisms of pediatric severe asthma and severity of symptoms would be helpful for developing personalized strategies for treatment and prevention.
For this study, ...698 medical histories of asthmatics between 6 and 18 years of age were reviewed in a period of 2 years. Variables analyzed were: age, sex, ethnicity, perinatological history, allergy history, asthma predictive index (API), exposure to tobacco, heavy traffic or epithelium, lung function, age of onset of symptoms, hospitalization admissions/PICU, systemic corticosteroids, daily symptoms control, device prescribe for daily control, and adherence.
A total of 86 children with severe asthma were included (12.3%). Mean age 13.3 +/- 1.86 years, sex ratio1:1, mean age of symptom onset 2.765 +/- 3.06 years, mean IgE 1076.18KU / L +/- 1136, mean eosinophils 604c / mcl +/- 511.9, mean of FEV1 93.15% +/- 16.3. Evidently, 70 children (81.4%) had positive API, 68 (79.1%) rhinitis, 34 (39.5%) atopic dermatitis. 73 (83.9%) sensitized to inhalants and 56 (65.1%) to dermatophagoides, 39 (45.3%) passive smokers, 19 (22.1%) exposure to heavy traffic; 55 (64%) showed symptoms with exercise, 35 (40.7%) had audible wheezing. The mean systemic corticosteroid cycles/year was 3.63 +/- 3.23, mean PICU admissions 0.36 +/- 0.83, mean hospital admissions 4.31 +/- 5.3, average emergency room visits/year 19.44 +/- 16.28. 38 (56.7%) had good adherence, 44 (51%) used an MDI device and 39 (45.3%) used dry powder.
Children with severe asthma meet the following criteria: premature, positive API, rhinitis, atopic dermatitis, high IgE, eosinophilia, passive smokers, exposure to heavy traffic, decreased lung function, and low adherence to controller medication.
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