Background:
Rapid and reliable diagnosis of tuberculosis (TB) represents a diagnostic challenge in compartmentalized extrapulmonary TB infection because of the small number of mycobacteria (MTB) and ...the frequent lack of fresh samples to perform culture. Here, we estimate the performances of homemade droplet digital PCR (ddPCR)-based assays against culture in 89 biopsies, for those fresh and formalin-fixed and paraffin-embedded (FFPE) subsamples were available.
Methods:
MTB diagnosis in fresh subsamples was performed by culture. Fresh subsamples were also analyzed for acid-fast bacilli smear-microscopy (AFB) and Xpert
®
MTB/RIF (Xpert). MTB examination was repeated in blind in the 89 FFPE subsamples by in-house ddPCR assays targeting the IS6110 and rpoB. Analytical sensitivity of ddPCR assays was evaluated using serial dilution of H37Rv strain. Limit of detection (LOD) was calculated by probit analysis. Results were expressed in copies/10
6
cells.
Results:
IS6110 and rpoB ddPCR assays showed a good linear correlation between expected and observed values (
R
2
: 0.9907 and 0.9743, respectively). Probit analyses predicted a LOD of 17 and 40 copies/10
6
cells of MTB DNA for IS6110 and rpoB, respectively. Of the 89 biopsies, 68 were culture positive and 21 were culture negative. Considering mycobacterial culture as reference method, IS6110 assay yielded positive results in 67/68 culture-positive samples with a median interquartile range (IQR) of 1,680 (550–8,444) copies/10
6
cells (sensitivity: 98.5%; accuracy: 98.9). These performances were superior to those reported by the rpoB assay in FFPE subsamples (sensitivity: 66.20%; accuracy: 74.1) and even superior to those reported by Xpert and AFB in fresh subsamples (sensitivity: 79.4 and 33.8%, respectively; accuracy: 84.3 and 49.4, respectively). When Xpert and AFB results were stratified according to mycobacterial load detected by rpoB and IS6110 ddPCR, bacterial load was lower in Xpert and AFB negative with respect to Xpert and AFB-positive samples (
p
= 0.003 and 0.01 for rpoB and
p
= 0.01 and 0.11 for IS6110), confirming the poor sensitivity of these methods in paucibacillary disease.
Conclusion:
ddPCR provides highly sensitive, accurate, and rapid MTB diagnosis in FFPE samples, as defined by the high concordance between IS6110 assay and culture results. This approach can be safely introduced in clinical routine to accelerate MTB diagnosis mainly when culture results remain unavailable.
•Mycobacterium xenopi proved to be the slowest growing of all mycobacterial species analysed.•A prolonged incubation time improves M. xenopi recovery and disease diagnosis.•M. xenopi was fully ...susceptible in vitro to all of the most commonly used antibiotics.
Mycobacterium xenopi is a nontuberculous mycobacterium (NTM) whose clinical diagnosis and drug susceptibility studies are frequently hampered by poor in vitro growth. Extending the culture incubation time from 42 days (common-standard) to 56 days could improve the likelihood of diagnosis and provide strains for phenotypic drug susceptibility profiling of this poorly studied but clinically relevant mycobacterium.
Time-to-positivity of mycobacterial cultures incubated for 56 days were analysed and compared. Clinical mycobacteriosis was defined by ATS/IDSA criteria. In vitro susceptibility of M. xenopi isolates was tested by broth microdilution.
Of 3852 mycobacteria-positive cultures (26 different mycobacterial species),M. xenopi required by far the longest growth time in culture, exceeding the 42 days commonly used in routine diagnostics in 41.2% of cases versus 4.7% for other NTM and 2.0% for Mycobacterium tuberculosis complex (P<0.001). Prolonging the incubation time to 56 days had a great impact on M. xenopi diagnosis, as 56.3% (27/48) of patients would have not fulfilled the ATS/IDSA criteria at an incubation limited to 42 days. All 40 M. xenopi isolates from patients with clinical mycobacteriosis were fully susceptibility to macrolides and rifamycins in vitro and to moxifloxacin, amikacin and linezolid.
These results indicate that a significant percentage (56.3%) of positive culture forM. xenopi would have incorrectly been reported as negative to clinicians without prolonging the incubation time to 56 days. Moreover, 56.3% of patients with M. xenopi disease would have missed the diagnosis along with an appropriate germ-based antimycobacterial treatment, otherwise fully effective.
Il presente contributo esplora la scrittura collaborativa all’interno di uno studio empirico giunto alla sua fase di analisi dei dati. Si tratta di interventi didattici effettuati presso la scuola ...primaria A. Rosmini di Bressanone (BZ) in cui gli alunni scrivono in più lingue e in cui l’uso della collaborazione è predominante. Si intendono identificare quelle caratteristiche e quei vantaggi di essa che contribuiscono a rafforzare le competenze di scrittura degli alunni. Dopo aver messo in evidenza come la scrittura collaborativa si sposi con un approccio basato sui processi portando diversi benefici, come poi sia strumento di affinamento linguistico ed abbia matrici pedagogiche di riferimento autorevoli (Don Milani e Mario Lodi), si prendono in considerazione esempi di ragionamenti ad alta voce degli alunni. Si conclude che la scrittura collaborativa è per l’insegnante una lente di ingrandimento sul lavoro degli alunni e per gli alunni stessi uno strumento di educazione democratica, nonché un’occasione di apprendimento linguistico e di crescita personale.
This article presents a comprehensive review of the key documents and laws governing early childhood education in the 0-6 age range, which have contributed to the development of an integrated and ...unified system in Italy. The analysis of these materials reveals how international policies implemented since the 2000s have progressively shaped a multifaceted concept of inclusion. Moving beyond the notion of eliminating barriers and addressing injustice faced by children in difficulty, there has been a paradigm shift towards a holistic understanding of the child, emphasizing the harmonization of physical, social, and cognitive aspects. The legislative guidelines increasingly incorporate important “constants” such as the significance of early childhood education and care (ECER) in early identification of difficulties, the connection to family, community, and peer environments, and the need for high-quality initial and ongoing teacher training. These recommendations offer valuable insights for all stakeholders involved. While reviewing the milestones of Italian legislation, this study acknowledges the progress made and the challenges addressed, yet it also recognizes the importance of further implementation of certain recommendations.
Nontuberculous mycobacteria are a rare but still emerging cause of difficult-to-treat prosthetic joint infection. To our knowledge only 17 cases of M. abscessus complex prosthetic joint infection are ...reported in literature, of which only 1 is by M. abscessus subps. abscessus. No guidelines are available for this clinical scenario.
We describe a 68-years-old female patient with an early-onset M. abscessus subsp. abscessus prosthetic joint infection, successfully treated with a tailored medical-surgical strategy, and present an overview of cases currently available in the literature to assist physicians in the management of these uncommon infections.
To evaluate the access to comprehensive diagnostics and novel antituberculosis medicines in European countries.
We investigated the access to genotypic and phenotypic Mycobacterium tuberculosis drug ...susceptibility testing and the availability of antituberculosis drugs and calculated the cost of drugs and treatment regimens at major tuberculosis treatment centres in countries of the WHO European region where rates of drug-resistant tuberculosis are the highest among all WHO regions. Results were stratified by middle-income and high-income countries.
Overall, 43 treatment centres from 43 countries participated in the study. For WHO group A drugs, the frequency of countries with the availability of phenotypic drug susceptibility testing was as follows: (a) 75% (30/40) for levofloxacin, (b) 82% (33/40) for moxifloxacin, (c) 48% (19/40) for bedaquiline, and (d) 72% (29/40) for linezolid. Overall, of the 43 countries, 36 (84%) and 24 (56%) countries had access to bedaquiline and delamanid, respectively, whereas only 6 (14%) countries had access to rifapentine. The treatment of patients with extensively drug-resistant tuberculosis with a regimen including a carbapenem was available only in 17 (40%) of the 43 countries. The median cost of regimens for drug-susceptible tuberculosis, multidrug-resistant/rifampicin-resistant tuberculosis (shorter regimen, including bedaquiline for 6 months), and extensively drug-resistant tuberculosis (including bedaquiline, delamanid, and a carbapenem) were €44 (minimum–maximum, €15–152), €764 (minimum–maximum, €542–15152), and €8709 (minimum–maximum, €7965–11759) in middle-income countries (n = 12) and €280 (minimum–maximum, €78–1084), €29765 (minimum–maximum, €11116–40584), and €217591 (minimum–maximum, €82827–320146) in high-income countries (n = 29), respectively.
In countries of the WHO European region, there is a widespread lack of drug susceptibility testing capacity to new and repurposed antituberculosis drugs, lack of access to essential medications in several countries, and a high cost for the treatment of drug-resistant tuberculosis.
Rifapentine, a synthetic derivate of rifampicin which was developed in 1965, has interesting pharmacological properties, including a long terminal half-life (13 h, compared to 2-3 h for rifampicin) ...and promising bactericidal activity against Mycobacterium tuberculosis. Despite being approved in 1998 by the US Food and Drug Administration (FDA) for the treatment of pulmonary tuberculosis, its global use has been limited by unavailability. In the past decade, new evidence has emerged to define rifapentine as a key component for treatment of active disease and latent infection with M. tuberculosis (LTBI).
Summary
Objectives
Rapid and reliable exclusion of invasive fungal infections (IFI) by markers able to avoid unnecessary empirical antifungal treatment is still a critical unmet clinical need. We ...investigated the diagnostic performance of a newly available β‐d‐Glucan (BDG) quantification assay, focusing on the optimisation of the BDG cut‐off values for IFI exclusion.
Methods
BDG results by Wako β‐glucan assay (lower limit of detection LLOD = 2.16 pg/mL, positivity ≥ 11 pg/mL) on two consecutive serum samples were retrospectively analysed in 170 patients, admitted to haematological wards (N = 42), intensive care units (ICUs; N = 80), or other wards (N = 48), exhibiting clinical signs and/or symptoms suspected for IFI. Only patients with proven IFI (EORTC/MSG criteria) were considered as true positives in the assessment of BDG sensitivity, specificity and predictive values.
Results
Patients were diagnosed with no IFI (69.4%), proven IFI (25.3%) or probable IFI (5.3%). Two consecutive BDG values < LLOD performed within a median of 1 (interquartile range: 1‐3) day were able to exclude a proven IFI with 100% sensitivity and negative predictive value (primary study goal). Test's specificity improved by using two distinct positivity and negativity cut‐offs (7.7 pg/mL and LLOD, respectively), but remained suboptimal in ICU patients (50%), as compared to haematological or other patients (93% and 90%, respectively).
Conclusions
The classification of Wako's results as negative when < LLOD, and positive when > 7.7 pg/mL, could be a promising diagnostic approach to confidently rule out an IFI in both ICU and non‐ICU patients. The poor specificity in the ICU setting remains a concern, due to the difficulty to interpret positive results in this fragile population.
serogroup 1 (Lp1) sequence type (ST) 23 is one of the most commonly detected STs in Italy where it currently causes all investigated outbreaks. ST23 has caused both epidemic and sporadic cases ...between 1995 and 2018 and was analysed at genomic level and compared with ST23 isolated in other countries to determine possible similarities and differences. A core genome multi-locus sequence typing (cgMLST), based on a previously described set of 1,521 core genes, and single-nucleotide polymorphisms (SNPs) approaches were applied to an ST23 collection including genomes from Italy, France, Denmark and Scotland. DNAs were automatically extracted, libraries prepared using NextEra library kit and MiSeq sequencing performed. Overall, 63 among clinical and environmental Italian Lp1 isolates and a further seven and 11 ST23 from Denmark and Scotland, respectively, were sequenced, and pangenome analysed. Both cgMLST and SNPs analyses showed very few loci and SNP variations in ST23 genomes. All the ST23 causing outbreaks and sporadic cases in Italy and elsewhere, were phylogenetically related independent of year, town or country of isolation. Distances among the ST23s were further shortened when SNPs due to horizontal gene transfers were removed. The Lp1 ST23 isolated in Italy have kept their monophyletic origin, but they are phylogenetically close also to ST23 from other countries. The ST23 are quite widespread in Italy, and a thorough epidemiological investigation is compelled to determine sources of infection when this ST is identified in both LD sporadic cases and outbreaks.
Multidrug-resistant/Rifampicin-resistant tuberculosis (TB) is a major obstacle to successful TB control. The recommendation by the World Health Organization to use bedaquiline, pretomanid, linezolid ...and moxifloxacin (BPaL(M)) for 6 months, based on results of three trials with high efficacy and low toxicity, has revolutionized treatment options.
In this study, representatives of the Tuberculosis Network European Trialsgroup (TBnet) in 44/54 countries of the WHO Europe region document the availability of the medicines and drug susceptibility testing (DST) of the BPaL(M) regimen through a structured questionnaire between September to November 2023.
24/44 (54.5%), 42/44 (95.5%), 43/44 (97.7%), and 43/44 (97.7%) had access to pretomanid, bedaquiline, linezolid, and moxifloxacin, respectively. Overall, 23/44 (52.3%) had access to all the drugs composing the BPaL(M) regimen. 7/44 (15.9%), 28/44 (63.6%), 34/44 (77.3%) and 36/44 (81.8%) had access to DST for pretomanid, bedaquiline, linezolid and moxifloxacin, respectively. DST was available for all medicines composing the BPaL(M) regimen in 6/44 (13.6%) countries.
Only in about half of the countries participating in the survey clinicians have access to all the BPaL(M) regimen drugs. In less than a fifth of countries, a complete DST is possible. Rapid scale up of DST capacity to prevent unnoticed spread of drug resistance and equal access to new regimens are urgently needed in Europe.
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