Antisepsis of the skin before spinal surgery with povidone iodine-alcohol followed by chlorhexidine gluconate-alcohol versus povidone iodine-alcohol applied twice for the prevention of contamination of the wound by bacteria: a randomised controlled trial

AIMS

The aim of this study was to determine whether the sequential application of povidone iodine-alcohol (PVI) followed by chlorhexidine gluconate-alcohol (CHG) would reduce surgical wound contamination to a greater extent than PVI applied twice in patients undergoing spinal surgery.

PATIENTS AND METHODS

A single-centre, interventional, two arm, parallel group randomised controlled trial was undertaken, involving 407 patients who underwent elective spinal surgery. For 203 patients, the skin was disinfected before surgery using PVI (10% [w/w (1% w/w available iodine)] in 95% industrial denatured alcohol, povidone iodine; Videne Alcoholic Tincture) twice, and for 204 patients using PVI once followed by CHG (2% [w/v] chlorhexidine gluconate in 70% [v/v] isopropyl alcohol; Chloraprep with tint). The primary outcome measure was contamination of the wound determined by aerobic and anaerobic bacterial growth from samples taken after disinfection.

RESULTS

The detection of viable bacteria in any one of the samples taken after disinfection (culture-positive) was significantly lower in the group treated with both PVI and CHG than in the group treated with PVI alone (59 (29.1%) versus 85 (41.7%), p = 0.009; odds ratio 0.574; 95% confidence interval, 0.380 to 0.866).

CONCLUSIONS

Antisepsis of the skin with the sequential application of PVI and CHG more effectively reduces the contamination of a surgical wound than PVI alone. Cite this article: Bone Joint J 2017;99-B:1354-65.

Thin high-order shims for small dipole NMR magnets

An NMR shim coil design method that addresses the severe spatial constraints of miniaturized dipole magnets is introduced. The fundamental design element, a collection of straight wires, is shown to be sufficient for producing a complete set of shim fields of high mathematical order. In accord with these theoretical considerations, a shim set is constructed using four wires in each of four directions to create all first through fourth order fields, except one. This shim set, with its supporting structure, occupies only 2mm of the available 5mm gap in a small 1.6T magnet. However, the fields produced by the individual wires are found to differ significantly from theoretical expectations. To produce the desired harmonic shim fields, the magnetic field of each of the 32 wires is mapped in three dimensions, and linear combinations of these maps are formed. The resulting shim fields are found to be very pure. The shims are used in a prototype high-resolution NMR magnet in which the 1.0mm sample size is only possible due to the thinness of the shim set. The resulting spectra demonstrate shimming to high resolution (<25ppb FWHM) without undue heating effects.

Intra- and inter-observer reproducibility of CINtec® PLUS in ThinPrep® cytology preparations

BACKGROUND

This study evaluated the intra- and inter-observer reproducibility of the dual-stain biomarker, CINtec^® PLUS cytology in ThinPrep^® specimens, for improved specificity in the detection of cervical disease in women testing human papillomavirus (HPV) positive.

METHODS

A total of 972 cases of HPV-positive women from a triage and primary HPV screening population were selected from an ongoing study evaluating the clinical performance of CINtec^® PLUS cytology. For reproducibility analyses, three cytotechnologists rescreened sets of slides which they had previously reported themselves and which were previously reported by each of the other cytotechnologists. The original results of slides previously screened by each of the three cytotechnologists were also compared with the results of an expert reference evaluator.

RESULTS

Intra- and inter-observer agreement for paired evaluations between reviewers ranged from 82.8% to 94.9% (kappa 0.65-0.91) and 89.2% to 93% (kappa 0.83-0.88), respectively. Reproducibility analyses between the cytotechnologists and the reference evaluator revealed agreements ranging from 95.5% to 98% (kappa 0.89-0.96).

CONCLUSION

Evaluation of the dual-stain biomarker showed a high level of agreement across all evaluators suggesting that CINtec^® PLUS cytology will perform well in the hands of cytotechnologists and pathologist reviewers and could be introduced into cellular pathology laboratories that employ ThinPrep^® LBC with a minimum effort.

Alternative medicine: an ethnographic study of how practitioners of Indian medical systems manage TB in Mumbai

BACKGROUND

Mumbai is a hot spot for drug-resistant TB, and private practitioners trained in AYUSH systems (Ayurveda, yoga, Unani, Siddha and homeopathy) are major healthcare providers. It is important to understand how AYUSH practitioners manage patients with TB or presumptive TB.

METHODS

We conducted semi-structured interviews of 175 Mumbai slum-based practitioners holding degrees in Ayurveda, homeopathy and Unani. Most providers gave multiple interviews. We observed 10 providers in clinical interactions, documenting: clinical examinations, symptoms, history taking, prescriptions and diagnostic tests.

RESULTS

No practitioners exclusively used his or her system of training. The practice of biomedicine is frequent, with practitioners often using biomedical disease categories and diagnostics. The use of homeopathy was rare (only 4% of consultations with homeopaths resulted in homeopathic remedies) and Ayurveda rarer (3% of consultations). For TB, all mentioned chest x-ray while 31 (17.7%) mentioned sputum smear as a TB test. One hundred and sixty-four practitioners (93.7%) reported referring TB patients to a public hospital or chest physician. Eleven practitioners (6.3%) reported treating patients with TB. Nine (5.1%) reported treating patients with drug-susceptible TB with at least one second-line drug.

CONCLUSIONS

Important sources of health care in Mumbai's slums, AYUSH physicians frequently use biomedical therapies and most refer patients with TB to chest physicians or the public sector. They are integral to TB care and control.

Bacterial proteases and haemostasis dysregulation in the CF lung

BACKGROUND

Pathogenic bacteria which chronically colonise the cystic fibrosis (CF) lung produce a number of virulence determinants, including distinct proteolytic activities. The potential role bacterial proteases play on haemostatic dysregulation within the CF lung is, however, poorly defined, despite haemoptysis being a common complication in CF.

METHODS

The potential impact of known CF pathogens (Pseudomonas aeruginosa and Burkholderia cepacia complex spp.) on haemostasis was examined for their ability to degrade fibrinogen and dysregulate fibrin clot formation and platelet aggregation.

RESULTS

Results demonstrate that key CF pathogens growing as a biofilm on mucin exhibit considerable fibrinogenolytic activity, resulting in fibrinogen breakdown, impaired clot formation, and modulation of platelet aggregation. Human neutrophil elastase may also contribute to fibrinogen breakdown and dysregulated clot formation at high concentration.

CONCLUSION

Bacterial-derived proteases may play an important role in the dysregulation of airway haemostasis, and potentially contribute to episodes of haemoptysis within the CF lung.

Understanding the role of Propionibacterium acnes in acne vulgaris: The critical importance of skin sampling methodologies

Acne vulgaris is a chronic inflammatory skin condition classified by the Global Burden of Disease Study as the eighth most prevalent disease worldwide. The pathophysiology of the condition has been extensively studied, with an increase in sebum production, abnormal keratinization of the pilosebaceous follicle, and an inflammatory immune response all implicated in its etiology. One of the most disputed points, however, is the role of the gram-positive anaerobic bacterium Propionibacterium acnes in the development of acne, particularly when this organism is also found in normal sebaceous follicles of healthy skin. Against this background, we now describe the different sampling strategies that have been adopted for qualitative and quantitative study of P acnes within intact hair follicles of the skin and discuss the strengths and weaknesses of such methodologies for investigating the role of P acnes in the development of acne.

Emendation of Propionibacterium acnes subsp. acnes (Deiko et al. 2015) and proposal of Propionibacterium acnes type II as Propionibacterium acnes subsp. defendens subsp. nov

Recently, it has been proposed that strains of Propionibacterium acnes from the type III genetic division should be classified as P. acnessubsp. elongatum subsp. nov., with strains from the type I and II divisions collectively classified as P. acnessubsp. acnes subsp. nov. Under such a taxonomic re-appraisal, we believe that types I and II should also have their own separate rank of subspecies. In support of this, we describe a polyphasic taxonomic study based on the analysis of publicly available multilocus and whole-genome sequence datasets, alongside a systematic review of previously published phylogenetic, genomic, phenotypic and clinical data. Strains of types I and II form highly distinct clades on the basis of multilocus sequence analysis (MLSA) and whole-genome phylogenetic reconstructions. In silico or digital DNA-DNA similarity values also fall within the 70-80 % boundary recommended for bacterial subspecies. Furthermore, we see important differences in genome content, including the presence of an active CRISPR/Cas system in type II strains, but not type I, and evidence for increasing linkage equilibrium within the separate divisions. Key biochemical differences include positive test results for β-haemolytic, neuraminidase and sorbitol fermentation activities with type I strains, but not type II. We now propose that type I strains should be classified as P. acnessubsp. acnes subsp. nov., and type II as P. acnessubsp. defendens subsp. nov. The type strain of P. acnessubsp. acnes subsp. nov. is NCTC 737T (=ATCC 6919T=JCM 6425T=DSM 1897T=CCUG 1794T), while the type strain of P. acnessubsp. defendens subsp. nov. is ATCC 11828 (=JCM 6473=CCUG 6369).

Use of standardised patients to assess antibiotic dispensing for tuberculosis by pharmacies in urban India: a cross-sectional study

BACKGROUND

India's total antibiotic use is the highest of any country. Patients often receive prescription-only drugs directly from pharmacies. Here we aimed to assess the medical advice and drug dispensing practices of pharmacies for standardised patients with presumed and confirmed tuberculosis in India.

METHODS

In this cross-sectional study in the three Indian cities Delhi, Mumbai, and Patna, we developed two standardised patient cases: first, a patient presenting with 2-3 weeks of pulmonary tuberculosis symptoms (Case 1); and second, a patient with microbiologically confirmed pulmonary tuberculosis (Case 2). Standardised patients were scheduled to present each case once to sampled pharmacies. We defined ideal management for both cases a priori as referral to a health-care provider without dispensing antibiotics or steroids or both.

FINDINGS

Between April 1, 2014, and Nov 29, 2015, we sampled 622 pharmacies in Delhi, Mumbai, and Patna. Standardised patients completed 1200 (96%) of 1244 interactions. We recorded ideal management (defined as referrals without the use of antibiotics or steroids) in 80 (13%) of 599 Case 1 interactions (95% CI 11-16) and 372 (62%) of 601 Case 2 interactions (95% CI 58-66). Antibiotic use was significantly lower in Case 2 interactions (98 [16%] of 601, 95% CI 13-19) than in Case 1 (221 [37%] of 599, 95% CI 33-41). First-line anti-tuberculosis drugs were not dispensed in any city. The differences in antibiotic or steroid use and number of medicines dispensed between Case 1 and Case 2 were almost entirely attributable to the difference in referral behaviour.

INTERPRETATION

Only some urban Indian pharmacies correctly managed patients with presumed tuberculosis, but most correctly managed a case of confirmed tuberculosis. No pharmacy dispensed anti-tuberculosis drugs for either case. Absence of a confirmed diagnosis is a key driver of antibiotic misuse and could inform antimicrobial stewardship interventions.

FUNDING

Grand Challenges Canada, Bill & Melinda Gates Foundation, Knowledge for Change Program, and World Bank Development Research Group.

Health changing conversations: clinicians' experience of health coaching in the East of England

The changing nature of healthcare and the challenge of long-term conditions require a paradigm shift in the mindset and behaviours of professionals. Central to this is the quality of clinician-patient communication, which determines how responsibility is shared. Health coaching training for clinicians provides them with new mindsets, communication skills and behaviour change techniques that transform the clinician--patient relationship and enables patients to become more active participants in their care. This training improves patient experience and health behaviours, provides self-management support and can reduce demand and costs. This article describes the East of England health coaching training programme and provides an overview of the evidence, required competencies and challenges clinicians experience when putting health coaching into practice. It illustrates that health coaching is a mechanism to deliver person-centred care. More must be done to provide clinicians with these much-needed skills especially in the management of long-term conditions.

HPV16 and HPV18 genotyping triage in young women with borderline cytology or mild dyskaryosis: effect of age on genotype-specific risk of high-grade CIN

OBJECTIVE

Human papillomavirus (HPV) triage of borderline cytology or mild dyskaryosis is limited by the higher prevalence of HPV in women with these findings relative to those with high-grade cervical intraepithelial neoplasia (≥CIN2). This is particularly relevant in young women in whom HPV prevalence is discernible. In a previous analysis of HPV triage and colposcopy outcomes in Northern Ireland, we revealed a substantial amount of prevalent high-grade disease in women below 30 years of age. We explored the role of genotyping for HPV16/HPV18 in this population by assessing the risk of high-grade lesions associated with these genotypes and the effect of age on type-specific risk.

METHODS

Of the 866 women eligible for HPV triage, those who tested positive for HPV were referred to colposcopy. The relative risk of ≥CIN2 for HPV16, HPV18 and non-HPV16/18 high-risk genotype positivity was determined for cobas(®) HPV Test-positive results.

RESULTS

The relative risk of high-grade CIN was significantly greater in women infected with HPV16 and/or HPV18 compared with non-HPV16/18 infections, regardless of age (2.23 and 0.45, respectively). In women under 30 years of age, HPV16-associated risk of ≥CIN2 was significantly greater than that of HPV18 and the non-HPV16/18 genotypes (1.74 versus 1.03 and 0.58, respectively). In women aged ≥30 years, HPV18 infection presented the greatest risk of ≥CIN2 (3.03). The relative risk of ≥CIN2 associated with non-HPV16/18 genotypes was lower (range, 0.32-0.58) for both age groups.

CONCLUSION

This analysis demonstrates the value of genotyping for HPV16/HPV18 and age stratification to improve the specificity of HPV triage and to tailor management relative to the risk of high-grade CIN and cancer.

Addressing the challenges of sleep/wake class imbalance in bed based non-contact actigraphic recordings of sleep

Utilising strategically positioned bed-mounted accelerometers, the Passive Sleep Actigraphy platform aims to deliver a non-contact method for identifying periods of wakefulness during night-time sleep. One of the key problems in developing data driven approaches for automatic sleep monitoring is managing the inherent sleep/wake class imbalance. In the current study, actigraphy data from three participants over a period of 30 days was collected. Upon examination, it was found that only 10% contained wake data. Consequently, this resulted in classifier overfitting to the majority class (sleep), thereby impeding the ability of the Passive Sleep Actigraphy platform to correctly identify periods of wakefulness during sleep; a key measure in the identification of sleep problems. Utilising Spread Subsample and Synthetic Minority Oversampling Techniques, this paper demonstrates a potential solution to this issue, reporting improvements of up to 28% in wake detection when compared to baseline data while maintaining an overall classifier accuracy of 90%.

Current and future trends in biomarker discovery and development of companion diagnostics for arthritis

Musculoskeletal diseases such as rheumatoid arthritis are complex multifactorial disorders that are chronic in nature and debilitating for patients. A number of drug families are available to clinicians to manage these disorders but few tests exist to target these to the most responsive patients. As a consequence, drug failure and switching to drugs with alternate modes of action is common. In parallel, a limited number of laboratory tests are available which measure biological indicators or 'biomarkers' of disease activity, autoimmune status, or joint damage. There is a growing awareness that assimilating the fields of drug selection and diagnostic tests into 'companion diagnostics' could greatly advance disease management and improve outcomes for patients. This review aims to highlight: the current applications of biomarkers in rheumatology with particular focus on companion diagnostics; developments in the fields of proteomics, genomics, microbiomics, imaging and bioinformatics and how integration of these technologies into clinical practice could support therapeutic decisions.

The opportunistic pathogen Propionibacterium acnes: insights into typing, human disease, clonal diversification and CAMP factor evolution

We previously described a Multilocus Sequence Typing (MLST) scheme based on eight genes that facilitates population genetic and evolutionary analysis of P. acnes. While MLST is a portable method for unambiguous typing of bacteria, it is expensive and labour intensive. Against this background, we now describe a refined version of this scheme based on two housekeeping (aroE; guaA) and two putative virulence (tly; camp2) genes (MLST₄) that correctly predicted the phylogroup (IA₁, IA₂, IB, IC, II, III), clonal complex (CC) and sequence type (ST) (novel or described) status for 91% isolates (n = 372) via cross-referencing of the four gene allelic profiles to the full eight gene versions available in the MLST database (http://pubmlst.org/pacnes/). Even in the small number of cases where specific STs were not completely resolved, the MLST₄ method still correctly determined phylogroup and CC membership. Examination of nucleotide changes within all the MLST loci provides evidence that point mutations generate new alleles approximately 1.5 times as frequently as recombination; although the latter still plays an important role in the bacterium's evolution. The secreted/cell-associated ‘virulence’ factors tly and camp2 show no clear evidence of episodic or pervasive positive selection and have diversified at a rate similar to housekeeping loci. The co-evolution of these genes with the core genome might also indicate a role in commensal/normal existence constraining their diversity and preventing their loss from the P. acnes population. The possibility that members of the expanded CAMP factor protein family, including camp2, may have been lost from other propionibacteria, but not P. acnes, would further argue for a possible role in niche/host adaption leading to their retention within the genome. These evolutionary insights may prove important for discussions surrounding camp2 as an immunotherapy target for acne, and the effect such treatments may have on commensal lineages.

An expanded multilocus sequence typing scheme for propionibacterium acnes: investigation of 'pathogenic', 'commensal' and antibiotic resistant strains

The Gram-positive bacterium Propionibacterium acnes is a member of the normal human skin microbiota and is associated with various infections and clinical conditions. There is tentative evidence to suggest that certain lineages may be associated with disease and others with health. We recently described a multilocus sequence typing scheme (MLST) for P. acnes based on seven housekeeping genes (http://pubmlst.org/pacnes). We now describe an expanded eight gene version based on six housekeeping genes and two ‘putative virulence’ genes (eMLST) that provides improved high resolution typing (91eSTs from 285 isolates), and generates phylogenies congruent with those based on whole genome analysis. When compared with the nine gene MLST scheme developed at the University of Bath, UK, and utilised by researchers at Aarhus University, Denmark, the eMLST method offers greater resolution. Using the scheme, we examined 208 isolates from disparate clinical sources, and 77 isolates from healthy skin. Acne was predominately associated with type IA₁ clonal complexes CC1, CC3 and CC4; with eST1 and eST3 lineages being highly represented. In contrast, type IA₂ strains were recovered at a rate similar to type IB and II organisms. Ophthalmic infections were predominately associated with type IA₁ and IA₂ strains, while type IB and II were more frequently recovered from soft tissue and retrieved medical devices. Strains with rRNA mutations conferring resistance to antibiotics used in acne treatment were dominated by eST3, with some evidence for intercontinental spread. In contrast, despite its high association with acne, only a small number of resistant CC1 eSTs were identified. A number of eSTs were only recovered from healthy skin, particularly eSTs representing CC72 (type II) and CC77 (type III). Collectively our data lends support to the view that pathogenic versus truly commensal lineages of P. acnes may exist. This is likely to have important therapeutic and diagnostic implications.