Paediatric tuberculosis diagnosis using Mycobacterium tuberculosis real-time polymerase chain reaction assay: a systematic review and meta-analysis

Background: Rapid and accurate diagnosis of paediatric tuberculosis (TB) is key to manage the disease and to control and prevent its transmission. Collection of quality sputum samples without invasion methods from paediatrics (age < 16 years) with presumptive pulmonary tuberculosis (PTB) remains a challenge. Thus, the aim of this meta-analysis was to assess the overall accuracy of a real-time polymerase chain reaction (RT-PCR)-based assay, for routine diagnosis of MTB in different samples from paediatrics with active pulmonary and extra-pulmonary tuberculosis using mycobacterial culture as the gold standard in clinical microbiology laboratories. Methods: We conducted a systematic review and meta-analysis to examine the diagnostic test accuracy of RT-PCR based assay for the detection of MTB in paediatric clinical samples. A systematic literature search was performed for publications in any language. MEDLINE via PubMed, EMBASE, and Web of Science were among 9 bibliographic databases searched from August 2019 until November 2020. Bivariate random-effects model of meta-analysis were performed to generate pooled summary estimates (95% CIs) for overall accuracy of RT-PCR based assay compared to mycobacterial culture as the reference standard. Results: Of the 1592 candidate studies, twenty-one eligible studies met our inclusion criteria. In total, the review and meta-analysis included 5536 (3209 PTB and 2327 EPTB). Summary estimates for pulmonary TB (11 studies) were as follows: sensitivity 56 (95% CI 51–62), specificity 97 (95% CI 96–98) and summary estimates for extra-pulmonary TB (10 studies) were as follows: sensitivity 87 (95% CI 82-91)) specificity 100 (95% CI 99–100). There was significant heterogeneity in sensitivity and specificity among the enrolled studies (p < 0.001). Conclusions: Our results suggested that the RT-PCR based assay could be a useful test for the diagnosis of paediatrics TB with high sensitivity and specificity in low-income/high-burden and upper medium income/low-burden settings. From the study, RT-PCR assay demonstrated a high degree of sensitivity for extra-pulmonary TB and good sensitivity for pulmonary TB which is an important factor in achieving effective global control and for patient management in terms of initiating early and appropriate anti-tubercular therapy

Paediatric tuberculosis diagnosis using Mycobacterium tuberculosis real-time polymerase chain reaction assay: protocol for systematic review and meta-analysis

Background: Tuberculosis (TB) diagnosis in children is a major challenge with up to 94% of children with TB treated empirically in TB high-burden countries. Paediatric tuberculosis (PTB) remains a major cause of morbidity and mortality globally, particularly in developing countries. Most deaths/morbidity from TB in paediatrics could be prevented with early diagnosis and appropriate treatment. The main objective of this systematic review is to examine the evidence whether real-time polymerase chain reaction assay could be the most accurate clinical laboratory diagnostic methodology for the Mycobacterium tuberculosis (MTB) detection in paediatrics. Methods: We will search MEDLINE/PubMed, EMBASE, BIOSIS, LILACS, Cochrane Infectious Diseases Group Specialised Register (CIDG SR), Global Health and CINAHL for published studies that recruited children less than 16 years of age being investigated for Mycobacterium tuberculosis (MTB) infection using real-time polymerase chain reaction assay accompanied by mycobacteriological culture investigation as the reference standard. There will be no restriction regarding the language, date of publication and publication status. We will include randomized controlled trials, observational studies (cohort, cross- sectional) in the review. Selection of studies, data extraction and management, assessment of risk of bias and quality of evidence will be performed by two independent reviewers (EB & BC). A third researcher will be consulted in case of discrepancies. Depending on the availability and quality of the data, a meta-analysis will be performed. Otherwise, findings will be qualitatively reported. Discussion: To our knowledge, this is the first systematic review and meta-analysis assessing the detection of MTB from all clinical samples’ types using real-time polymerase chain reaction assay in paediatric population. This review will make available evidence on the accuracy, approach and interpretation of results of this assay in the context of MTB diagnosis will meet an urgent need, considering the challenges of MTB diagnosis in paediatrics Systematic review registration: PROSPERO CRD4201810405

Optimal detection of carbapenemase-producing Enterobacteriaceae from rectal samples: a role for enrichment?

BACKGROUND: Successful laboratory detection of carbapenemase-producing Enterobacteriaceae (CPE) in patient surveillance samples is a diagnostic challenge. In the absence of a reference standard for screening rectal swabs for CPE, many phenotypic, genotypic, culture- and non-culture-based assays have been proposed for identifying these bacteria. AIM: To develop and optimize a CPE screening protocol capable of identifying all frequently encountered CPE, including those producing OXA-48-like carbapenemases. METHODS: Faropenem susceptibility testing was performed on 507 presumptive CPE isolated from diagnostic samples and CPE rectal screens between March and August 2016. Results from this CPE screening method were compared to those from direct culture on mSuperCARBA™, temocillin enrichment culture, and use of an antibiotic resistance algorithm, to determine the optimal method to employ in the detection of CPE. FINDINGS: Faropenem was a poor predictor of carbapenemase production (58% true positives). The combination of a temocillin enrichment stage and interpretive reading of antibiotic resistance phenotypes improved the recovery and identification of CPE significantly (91% true positives), especially for OXA-48 producers (P = 0.03). CONCLUSION: The combination of temocillin enrichment, a selective chromogenic medium, and an antibiotic resistance-based algorithm significantly improved the detection of all CPE recovered from routine and targeted surveillance samples

Hospital outbreak of carbapenem-resistant Enterobacterales associated with a bla OXA-48 plasmid carried mostly by Escherichia coli ST399

A hospital outbreak of carbapenem-resistant Enterobacterales was detected by routine surveillance. Whole genome sequencing and subsequent analysis revealed a conserved promiscuous blaOXA-48 carrying plasmid as the defining factor within this outbreak. Four different species of Enterobacterales were involved in the outbreak. Escherichia coli ST399 accounted for 35 of all the 55 isolates. Comparative genomics analysis using publicly available E. coli ST399 genomes showed that the outbreak E. coli ST399 isolates formed a unique clade. We developed a mathematical model of pOXA-48-like plasmid transmission between host lineages and used it to estimate its conjugation rate, giving a lower bound of 0.23 conjugation events per lineage per year. Our analysis suggests that co-evolution between the pOXA-48-like plasmid and E. coli ST399 could have played a role in the outbreak. This is the first study to report carbapenem-resistant E. coli ST399 carrying blaOXA-48 as the main cause of a plasmid-borne outbreak within a hospital setting. Our findings suggest complementary roles for both plasmid conjugation and clonal expansion in the emergence of this outbreak

Third generation cephalosporin use in a tertiary hospital in Port of Spain, Trinidad: need for an antibiotic policy

BACKGROUND: Tertiary care hospitals are a potential source for development and spread of bacterial resistance being in the loop to receive outpatients and referrals from community nursing homes and hospitals. The liberal use of third-generation cephalosporins (3GCs) in these hospitals has been associated with the emergence of extended-spectrum beta- lactamases (ESBLs) presenting concerns for bacterial resistance in therapeutics. We studied the 3GC utilization in a tertiary care teaching hospital, in warded patients (medical, surgical, gynaecology, orthopedic) prescribed these drugs. METHODS: Clinical data of patients (≥ 13 years) admitted to the General Hospital, Port of Spain (POSGH) from January to June 2000, and who had received 3GCs based on the Pharmacy records were studied. The Sanford Antibiotic Guide 2000, was used to determine appropriateness of therapy. The agency which procures drugs for the Ministry of Health supplied the cost of drugs. RESULTS: The prevalence rate of use of 3GCs was 9.5 per 1000 admissions and was higher in surgical and gynecological admissions (21/1000) compared with medical and orthopedic (8 /1000) services (p < 0.05). Ceftriaxone was the most frequently used 3GC. Sixty-nine (36%) patients without clinical evidence of infection received 3Gcs and prescribing was based on therapeutic recommendations in 4% of patients. At least 62% of all prescriptions were inappropriate with significant associations for patients from gynaecology (p < 0.003), empirical prescribing (p < 0.48), patients with undetermined infection sites (p < 0.007), and for single drug use compared with multiple antibiotics (p < 0.001). Treatment was twice as costly when prescribing was inappropriate CONCLUSIONS: There is extensive inappropriate 3GC utilization in tertiary care in Trinidad. We recommend hospital laboratories undertake continuous surveillance of antibiotic resistance patterns so that appropriate changes in prescribing guidelines can be developed and implemented. Though guidelines for rational antibiotic use were developed they have not been re-visited or encouraged, suggesting urgent antibiotic review of the hospital formulary and instituting an infection control team. Monitoring antibiotic use with microbiology laboratory support can promote rational drug utilization, cut costs, halt inappropriate 3GC prescribing, and delay the emergence of resistant organisms. An ongoing antibiotic peer audit is suggested

A review of the current treatment methods for posthaemorrhagic hydrocephalus of infants

Posthaemorrhagic hydrocephalus (PHH) is a major problem for premature infants, generally requiring lifelong care. It results from small blood clots inducing scarring within CSF channels impeding CSF circulation. Transforming growth factor – beta is released into CSF and cytokines stimulate deposition of extracellular matrix proteins which potentially obstruct CSF pathways. Prolonged raised pressures and free radical damage incur poor neurodevelopmental outcomes. The most common treatment involves permanent ventricular shunting with all its risks and consequences

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is the most common acute hyperglycaemic emergency in people with diabetes mellitus. A diagnosis of DKA is confirmed when all of the three criteria are present — ‘D’, either elevated blood glucose levels or a family history of diabetes mellitus; ‘K’, the presence of high urinary or blood ketoacids; and ‘A’, a high anion gap metabolic acidosis. Early diagnosis and management are paramount to improve patient outcomes. The mainstays of treatment include restoration of circulating volume, insulin therapy, electrolyte replacement and treatment of any underlying precipitating event. Without optimal treatment, DKA remains a condition with appreciable, although largely preventable, morbidity and mortality. In this Primer, we discuss the epidemiology, pathogenesis, risk factors and diagnosis of DKA and provide practical recommendations for the management of DKA in adults and children

Extended-Spectrum Beta-Lactamase Producing Enterobacteriaceae in a Tertiary Care Hospital in Trinidad and Tobago

Extended-spectrum beta-lactamase (ESBL) mediated resistance to third generation cephalosporins, amongst the family Enterobacteriaceae, is emerging wordwide. This is the Caribbean’s first survey on ESBL production, and was conducted during two six- month periods in 1998 and 2001, in a tertiary health institution in Trinidad and Tobago. Consecutive ampicillin resistant isolates of the family Enterobacteriaceae from in-patients were screened for resistance to third generation cephalosporins, and for ESBL production. The proportion of isolates found to be ESBL producers was similar in both samples (40 of 560 and 23 of 361). Overall, ESBL production was more frequent in enterobacter, citrobacter and proteus (and related organisms) than in Klebsiella and Escherichia (11.2% and 4.6%, respectively, p < 0.001). In the 1998 sample, this proportion (9.8% versus 5.8%) was significant (p < 0.05), but the difference was more marked in the 2001 sample (13.6% versus 2.9%, p < 0.001). Continued distribution of these resistant bacterial strains is of concern. In the Caribbean region, more laboratory surveillance and increased infection control vigilance are recommended, with focus on specific genera in the family