Potential for nosocomial transmission of multidrug-resistant (MDR) tuberculosis in a South African tertiary hospital

Background. Tuberculosis (TB) is a major health problem in the Western Cape, with an incidence exceeding 900 per 100 000 people. Nosocomial transmission of TB, and particularly drug-resistant TB, is a potential risk that may be undetected. Rapid diagnosis and rapid institution of effective anti-TB treatment, combined with appropriate infection control measures, are essential to prevent nosocomial transmission of TB. To estimate the potential for nosocomial transmission, we aimed to determine the in-hospital delays in diagnosis and treatment of patients with multidrug-resistant (MDR)-TB at a tertiary care hospital. Methods. A descriptive study, based on retrospective review of patient records and laboratory data, including all adult patients (>13 years) where TB culture and susceptibility testing confirmed MDR-TB on specimens submitted to Tygerberg Hospital’s National Health Laboratory Service (NHLS) laboratory in 2007. Results. Thirty-one patients with MDR-TB were identified. The median laboratory turnaround time (TAT) from collection of specimen to confirmation of MDR-TB was 40 days, while the median time from the time of first presentation at Tygerberg Hospital to institution of MDR treatment was 44 days. Twenty patients were considered infectious during their hospital stay, generating 345 inpatient infectious days. Conclusions. The study suggests that there is an ongoing substantial risk for nosocomial transmission of MDR-TB at Tygerberg Hospital. We propose improvements, including the use of rapid drug susceptibility testing. The consistent application of infection control measures to prevent nosocomial spread of TB, including MDR-TB, remains vital

Validation of a severity-of-illness score in patients with tuberculosis requiring intensive care unit admission

Background. There is a paucity of data on the determinants of mortality due to tuberculosis (TB) in the intensive care unit (ICU).Objective. To develop a simple severity-of-illness score for use in patients with TB admitted to an ICU.Methods. A scoring system was generated by retrospectively identifying the four most significant and clinically unrelated predictors of mortality from an existing prospectively collected dataset (January 2012 - May 2013), and combining these with known predictors of poor outcome.Results. Of 83 patients admitted with TB, 38 (45.8%) died in the ICU. The four parameters identified from the retrospective analysis were: (i) HIV co-infection with a CD4 cell count <200/ƒÊL; (ii) a raised creatinine level: (iii) a chest radiograph showing diffuse parenchymal infiltrates/miliary pattern; and (iv) absence of TB treatment on admission. These were combined with septic shock and a low arterial partial pressure of oxygen/fractional inspired oxygen (P:F) ratio to generate a six-point severity-of-illness score (one point for each parameter). The scores for survivors were significantly lower than those for  non-survivors (mean (standard deviation) 2.27 (1.47) v. 3.58 (1.08); p<0.01). A score of .2 was associated with significantly higher mortality than a score of <2 (7.1% v. 46.4%; odds ratio (OR) 15.03; 95% confidence interval (CI) 1.86 - 121.32; p<0.01), whereas a score of .3 was associated with a significantly higher mortality than a score of <3 (64.6% v. 20.0%; OR 7.29; 95% CI 2.64 - 20.18; p<0.01).Conclusion. The proposed scoring system identified patients at increased risk of dying from TB in the ICU. Further prospective studies are indicated to validate its use

The impact of HIV infection on the presentation of lung cancer in South Africa

Background. Despite the very high background prevalence of HIV and smoking-related diseases in sub-Saharan Africa, very little is known about the presentation of lung cancer in HIV-infected individuals.Methods. We prospectively compared HIV-positive (n=44) and HIV-negative lung cancer patients (n=425) with regard to demographics, cell type, performance status and tumour node metastasis staging at initial presentation.Results. HIV-positive patients were found to be younger than HIV-negative (mean 54.1 (standard deviation 8.4) years v. 60.5 (10) years, p<0.01), more likely to have squamous cell carcinoma (43.2% v. 30.1%, p=0.07) and significantly more likely to have a poor Eastern Cooperative Oncology Group (ECOG) performance status of ≥3 (47.7% v. 29.4%, p=0.02). In the case of non-small cell-lung cancer, they were also significantly less likely to have early stage lung cancer (0% v. 10.3%, p=0.02)  compared with HIV-negative patients.Conclusions. HIV-positive lung cancer patients were younger, significantly more likely to have a poor performance status at presentation and significantly less likely to have early stage lung cancer when compared with HIV-negative patients

Imputation strategies for missing binary outcomes in cluster randomized trials

<p>Abstract</p> <p>Background</p> <p>Attrition, which leads to missing data, is a common problem in cluster randomized trials (CRTs), where groups of patients rather than individuals are randomized. Standard multiple imputation (MI) strategies may not be appropriate to impute missing data from CRTs since they assume independent data. In this paper, under the assumption of missing completely at random and covariate dependent missing, we compared six MI strategies which account for the intra-cluster correlation for missing binary outcomes in CRTs with the standard imputation strategies and complete case analysis approach using a simulation study.</p> <p>Method</p> <p>We considered three within-cluster and three across-cluster MI strategies for missing binary outcomes in CRTs. The three within-cluster MI strategies are logistic regression method, propensity score method, and Markov chain Monte Carlo (MCMC) method, which apply standard MI strategies within each cluster. The three across-cluster MI strategies are propensity score method, random-effects (RE) logistic regression approach, and logistic regression with cluster as a fixed effect. Based on the community hypertension assessment trial (CHAT) which has complete data, we designed a simulation study to investigate the performance of above MI strategies.</p> <p>Results</p> <p>The estimated treatment effect and its 95% confidence interval (CI) from generalized estimating equations (GEE) model based on the CHAT complete dataset are 1.14 (0.76 1.70). When 30% of binary outcome are missing completely at random, a simulation study shows that the estimated treatment effects and the corresponding 95% CIs from GEE model are 1.15 (0.76 1.75) if complete case analysis is used, 1.12 (0.72 1.73) if within-cluster MCMC method is used, 1.21 (0.80 1.81) if across-cluster RE logistic regression is used, and 1.16 (0.82 1.64) if standard logistic regression which does not account for clustering is used.</p> <p>Conclusion</p> <p>When the percentage of missing data is low or intra-cluster correlation coefficient is small, different approaches for handling missing binary outcome data generate quite similar results. When the percentage of missing data is large, standard MI strategies, which do not take into account the intra-cluster correlation, underestimate the variance of the treatment effect. Within-cluster and across-cluster MI strategies (except for random-effects logistic regression MI strategy), which take the intra-cluster correlation into account, seem to be more appropriate to handle the missing outcome from CRTs. Under the same imputation strategy and percentage of missingness, the estimates of the treatment effect from GEE and RE logistic regression models are similar.</p

The prevalence of stillbirths: a systematic review

BACKGROUND: Stillbirth rate is an important indicator of access to and quality of antenatal and delivery care. Obtaining overall estimates across various regions of the world is not straightforward due to variation in definitions, data collection methods and reporting. METHODS: We conducted a systematic review of a range of pregnancy-related conditions including stillbirths and performed meta-analysis of the subset of studies reporting stillbirth rates. We examined variation across rates and used meta-regression techniques to explain observed variation. RESULTS: We identified 389 articles on stillbirth prevalence among the 2580 included in the systematic review. We included 70 providing 80 data sets from 50 countries in the meta-analysis. Pooled prevalence rates show variation across various subgroup categories. Rates per 100 births are higher in studies conducted in less developed country settings as compared to more developed (1.17 versus 0.50), of inadequate quality as compared to adequate (1.12 versus 0.66), using sub-national sample as compared to national (1.38 versus 0.68), reporting all stillbirths as compared to late stillbirths (0.95 versus 0.63), published in non-English as compared to English (0.91 versus 0.59) and as journal articles as compared to non-journal (1.37 versus 0.67). The results of the meta-regression show the significance of two predictor variables – development status of the setting and study quality – on stillbirth prevalence. CONCLUSION: Stillbirth prevalence at the community level is typically less than 1% in more developed parts of the world and could exceed 3% in less developed regions. Regular reviews of stillbirth rates in appropriately designed and reported studies are useful in monitoring the adequacy of care. Systematic reviews of prevalence studies are helpful in explaining sources of variation across rates. Exploring these methodological issues will lead to improved standards for assessing the burden of reproductive ill-health

Utilization of antenatal ultrasound scan and implications for caesarean section: a cross-sectional study in rural Eastern China

<p>Abstract</p> <p>Background</p> <p>Antenatal ultrasound scan is a widely accepted component of antenatal care. Studies have looked at the relationship between ultrasound scanning and caesarean section (CS) in certain groups of women in China. However, there are limited data on the utilization of antenatal ultrasound scanning in the general population, including its association with CS. The purpose of this study is to describe the utilization of antenatal ultrasound screening in rural Eastern China and to explore the association between antenatal ultrasound scan and uptake of CS.</p> <p>Methods</p> <p>Based on a cluster randomized sample, a total of 2326 women with childbirth participated in the study. A household survey was conducted to collect socio-economic information, obstetric history and utilization of maternal health services.</p> <p>Results</p> <p>Coverage of antenatal care was 96.8% (2251/2326). During antenatal care, 96.1% (2164/2251) women received ultrasound screening and the reported average number was 2.55. 46.8% women received at least 3 ultrasound scans and the maximum number reached 11. The CS rate was found to be 54.8% (1275/2326). After adjusting for socio-demographic and clinical variables, it showed a statistically significant association between antenatal ultrasound scans and uptake of CS by multivariate logistic regression model. High husband education level, high maternal age, having previous adverse pregnant outcome and pregnancy complications during the index pregnancy were also found to be risk factors of choosing a CS.</p> <p>Conclusions</p> <p>A high use of antenatal ultrasound scan in rural Eastern China is found and is influenced by socio-demographic and clinical factors. Evidence-based guidelines for antenatal ultrasound scans need to be developed and disseminated to clinicians including physicians, nurses and sonographers. Guidance about the appropriate use of ultrasound scans should also be shared with women in order to discourage unreasonable expectations and demands. It is important to monitor the use of antenatal ultrasound scan as well as the indications for caesarean section in rural China.</p

Reinvigorating stagnant science: Implementation laboratories and a meta-laboratory to efficiently advance the science of audit and feedback

Audit and feedback (A&F) is a commonly used quality improvement (QI) approach. A Cochrane review indicates that A&F is generally effective and leads to modest improvements in professional practice but with considerable variation in the observed effects. While we have some understanding of factors that enhance the effects of A&F, further research needs to explore when A&F is most likely to be effective and how to optimise it. To do this, we need to move away from two-arm trials of A&F compared with control in favour of head-to-head trials of different ways of providing A&F. This paper describes implementation laboratories involving collaborations between healthcare organisations providing A&F at scale, and researchers, to embed head-to-head trials into routine QI programmes. This can improve effectiveness while producing generalisable knowledge about how to optimise A&F. We also describe an international meta-laboratory that aims to maximise cross-laboratory learning and facilitate coordination of A&F research

Reinvigorating stagnant science: implementation laboratories and a meta-laboratory to efficiently advance the science of audit and feedback

Audit and feedback (A&F) is a commonly used quality improvement (QI) approach. A Cochrane review indicates that A&F is generally effective and leads to modest improvements in professional practice but with considerable variation in the observed effects. While we have some understanding of factors that enhance the effects of A&F, further research needs to explore when A&F is most likely to be effective and how to optimise it. To do this, we need to move away from two-arm trials of A&F compared with control in favour of head-to-head trials of different ways of providing A&F. This paper describes implementation laboratories involving collaborations between healthcare organisations providing A&F at scale, and researchers, to embed head-to-head trials into routine QI programmes. This can improve effectiveness while producing generalisable knowledge about how to optimise A&F. We also describe an international meta-laboratory that aims to maximise cross-laboratory learning and facilitate coordination of A&F research