Rakesh Panchal

The effectiveness of primary care based risk stratification for targeted latent tuberculosis infection screening in recent immigrants to the UK: a retrospective cohort study

Background Most UK tuberculosis (TB) cases occur in immigrants from high TB incidence areas, implicating reactivation of imported latent TB infection (LTBI). Strategies to identify and treat immigrant LTBI in primary care at the time of first registration (coded Flag-4) may be effective. Methods This was an 11-year retrospective cohort study to evaluate effectiveness of LTBI screening in recent immigrants to Leicestershire at their time of primary care registration. We examined the temporal relationship between dates of Flag-4 primary care registration (n=59 007) and foreign-born TB (FB-TB) cases (n=857), for immigrants arriving to the UK after 1999. TB diagnosed >6 months after registration was considered potentially preventable with screening. Primary outcomes were the potentially preventable proportion of FB-TB and the number needed to screen (NNS) of immigrants to identify one potentially preventable case, stratified by age and region of origin. Results 250 cases (29%) were potentially preventable in Flag-4-registered immigrants. Overall, 511 cases (60%) were potentially preventable among primary-care registered immigrants, implying a significant proportion without Flag-4 status. Prospective TB incidence (95% CI) after Flag-4 registration was 183 (163 to 205) cases/100 000 person-years, with a NNS (95% CI) of 145 (130 to 162). Targeted screening was most effective for 16–35 year olds from TB incidence regions 150–499/100 000 (NNS (95% CI)=65 (57 to 74), preventing 159 (18.7%) cases). Unpreventable TB risk increased with delayed primary care registration after UK entry (p<0.001) and was associated with HIV seropositivity (relative risk (95% CI)=1.89 (1.25 to 2.84), p=0.003). Conclusions LTBI screening at primary care registration offers an effective strategy for potentially identifying immigrants at high risk of developing TB.

Book Review: Oxford Respiratory Medicine Library: Acute Respiratory Infections

Acute Respiratory Infections is the fifth addition to the Oxford Respiratory Medicine Library (ORML). In keeping with the series titles, it is published as a pocket book, which is portable, accessible and follows a practical format that is easy to read and suits the busy health care professional. Each chapter is preceded by a summary of the key points and is complemented by key tables, algorithms, illustrated using relevant radiology and ends with recommendations that refer to the latest evidence base for further reading. Infections of the respiratory tract are a common cause for consultation and presentation in both primary and secondary care, respectively. Nevertheless, respiratory infections can be challenging and in the acute setting, there is a paucity of texts that deal with this vast subject area in a concise and succinct manner. This text focuses on the most common and difficult to manage infections that are likely to be encountered in primary and secondary care. Infections in the immunocompromised are separated into those in patients with HIV co-infection and those with haematological disorders, which is useful from a practical perspective. In the latter group, a diagnostic algorithm based on the radiological appearance of consolidation, ground glass, tree in bud and so on is particularly useful as management decisions are often dictated by the correlation of clinical findings to the radiology. Surprisingly, tuberculosis, which is on the rise in the United Kingdom and can often pose a diagnostic conundrum in the acute setting, is only presented in the context of HIV infection rather than in separate chapter unlike Legionnaires’ disease. I would say this is a major omission of the text. The chapter on pleural infection is particularly well written and illustrated and provides information on all the various treatment modalities that are available to the managing physician. The recent flu pandemic and its management as well as that of pneumococcal disease and its vaccination is summarised well in the last couple of chapters and provides a useful aide-memoire for both the primary and secondary care physician. Overall, the text serves as a useful reference in the busy GP surgery or ward environment and would also be a useful revision aid for medical students and also respiratory specialist trainees preparing for the UK specialist certificate examination (SCE) in respiratory medicine. I would recommend this text be kept in all surgeries, medical admissions units and respiratory wards that look after patients with acute respiratory infections.

P242 The prognosis of patients diagnosed with pulmonary adenocarcinoma at local anaesthetic thoracoscopy (lat): the role of primary t stage

Background Adenocarcinoma is the commonest type of lung cancer and may present with metastatic malignant pleural effusion (MPE)1 We observed that some patients with pulmonary adenocarcinoma diagnosed at LAT did not have radiological evidence of primary lung parenchymal lesion. We hypothesised that these patients may have a better prognosis than those with lung nodules or masses due to reduced tumour burden. Methods We retrospectively reviewed all patients who underwent LAT from 2006–2016 and screened those diagnosed with pulmonary adenocarcinoma. We reviewed these patients’ radiology, age, gender, TNM staging and prognosis. Results 491 patients underwent LAT from 2006–2016. 69/491 (14.05%) were diagnosed with pulmonary adenocarcinoma on histology of parietal pleura. 8 patients out of 69 (3 females, 5 males; mean age 68.25 years) did not have any radiologically detectable lung parenchymal lesion. The TNM staging (7th edition) of these eight patients without lung parenchymal lesion was T0N0M1a, T0N2M1a, T0N2M1a, T0N3M1a, T0N3M1a, T0N0M1b, T0N1M1b, T0N2M1b. Overall prognosis of MPE with lung parenchymal lesion was 331.7+/-63.14 days and without lung parenchymal lesion was 143.5 +/– 32.8 days, p=0.31 (figure 1) Abstract P242 Figure 1 Conclusion We have demonstrated no significant difference in the prognosis of patients with MPE secondary to pulmonary adenocarcinoma in the absence or presence of a radiologically determined primary lung parenchymal lesion. Although not statistically different (p=0.31) those patients without a primary lung parenchymal lesion may have a worse prognosis and this requires further investigation in larger cohorts as this may prove to be an important prognostic factor for MPE. Reference Kasapoglu US, Arinç S, Gungor S, Irmak I, Guney P, Aksoy F, Bandak D, Hazar A. Prognostic factors affecting survival in non-small cell lung carcinoma patients with malignant pleural effusions. The Clinical Respiratory Journal2016;10:791–799.

Book Review: Interventions in Pulmonary Medicine

Interventional Pulmonology focuses on using advanced diagnostic and therapeutic techniques for treatment of lung cancer, benign airway disorders and pleural diseases. It is an area of respiratory medicine with rapidly evolving technology and shows tremendous scope for development, but there is a paucity of comprehensive texts in this subject area. Interventions in Pulmonary Medicine has a varied authorship and covers all the hot topics that would appeal to the budding interventional pulmonologist. The book is divided into seven parts, which broadly range from basic endoscopy to more advanced procedures involved in tracheobronchial obstructions, lung cancer diagnosis and staging, pleural diseases and airways diseases. There is also a chapter on the role of bronchoscopy in special situations such as interstitial lung disease and the intensive care unit and thus something for all scenarios. Each chapter is written from the perspective of an interventionalist with the latest evidence base and well illustrated using pictures that are pertinent to the procedures being discussed. The chapters are complemented with the associated radiology where relevant and a discussion of the likely complications that one may encounter in clinical practice. The chapter on pleural procedures is particularly useful as medical thoracoscopy and indwelling pleural catheters are now common place and there is a detailed and illustrated step-by-step guide on how to perform each of these procedures, respectively. There are comprehensive reviews on the topical issues of the various modalities available for endoscopic lung volume reduction and the technique of bronchial thermoplasty. There is wide variation in the practice of advanced interventional procedures across Europe, and therefore, this book serves as a good introductory reference text for all respiratory physicians wishing to specialize in interventional procedures and I would recommend that it should be kept in all bronchoscopy suites.

P58 Indices of TB risk can help stratify recent immigrants registering with a GP for targeted screening

Introduction The burden of tuberculosis (TB) in the UK may only be lowered significantly by identification and treatment of latent infection with M tuberculosis (LTBI) in recent immigrants from moderate (150–499/100 000) and high prevalence (500+/100 000) regions of disease. An approach that focuses immigrant capture to a limited number of GP practices is feasible in our region as the distribution of registrations and TB cases by GP practice is heavily skewed. However, strategies for identifying the most appropriate practices and immigrant subgroups for targeted screening are not known. Aims To evaluate indices of TB risk that may inform targeted screening strategies for newly registering immigrants to Leicestershire (Exeter/Flag-4). Methods A retrospective analysis was performed of all Flag 4 immigrant registrations between 2000 and 2010 and collated with data for all TB notifications over the same period. The top 10 practices defined by number of registrations (10R), number of TB cases (10TB) and a weighted index [WI=(TB cases/immigrant registrations) × TB cases] were identified and compared. Logistic regression was performed to model independent predictors of TB events. TB risk for specified immigrant subgroups was estimated using Kaplan–Meier analysis and pair-wise comparisons of risk computed as the rate ratio (95% CI). Results 564 TB cases were recorded in 34 764 registered immigrants at 148 practices. Independent predictors of TB risk were immigrant age at registration and gender and deprivation index of the GP practice locality. Compared with registration at a non-top 10 practice, the corresponding rate ratios for TB after 5 years at a top 10 practice were 1.32 (95% CI 1.1 to 1.57) for 10R; 1.72 (95% CI 1.44 to 2.1) for 10TB and 1.79 (95% CI 1.5 to 2.14) for 10WI. Compared with the unselected registering immigrant population, the 5 and 10 year TB rates in 10WI practices were significantly higher for immigrants aged 16–35 years but not older adults >35 years (Abstract P58 table 1).Abstract P58 Table 1 TB rate/100 000 person years Age groups 16–35 Over 35 Top 10 weighted index (N=6579) All (N=21 136) Top 10 weighted index (N=4278) All (N=7312) 5 year 2479 (218) 1695 (104) 1586 (209) 1347 (151) Rate ratio (95% CI) 1.46 (1.22 to 1.76); p=0.002 1.18 (0.87 to 1.6); p=0.3 10 year 3875 (326) 2728 (156) 2365 (275) 2138 (224) Rate ratio (95% CI) 1.42 (1.23 to 1.64); p<0.001 1.11 (0.86 to 1.42); p=0.42 Conclusion TB risk among immigrants newly registering with a GP is heterogeneous. Indices for risk stratification are identifiable that may improve cost-effectiveness of targeted screening.

P59 Differing patterns of new immigrant GP registration among ethnic subgroups determine the importance of additional strategies for models of new immigrant screening

Introduction New immigrant GP registration databases maybe an important tool for identifying recent immigrants to the UK at high risk of latent infection with M tuberculosis (LTBI), who may benefit from screening and treatment to prevent tuberculosis (TB). However, effectiveness of this strategy is determined by the proportion of immigrants that register and the time after UK entry that registration occurs. Aims To evaluate whether differences exist in the pattern of GP registration onto the new immigrant registration database for Leicestershire (Flag-4), between immigrants stratified by age group (<16, 16–35 or =36 years) and ethnicity (Indian sub-continent [ISC] or Black African). Methods A retrospective analysis was performed of all immigrants entering the UK after 1999 that were Flag-4 registered between 2000 and 2010 (N=29186) and collated with data for all TB notifications over the same period (N=884). Comparisons were made between immigrants developing TB and staying healthy; and between TB cases occurring in foreign born persons captured or missed by the new immigrant database. Among captured cases, the proportion with a notification date at least 12 months after UK entry and 4 months after GP registration were considered preventable. Results There was a significant and inverse relationship for the proportions of cases captured and missed by the Flag-4 system in black Africans and ISC immigrants (Abstract P59 table 1, p<0.001). The higher proportion of missed cases in black Africans was evident for both adult age groups but not children. Among registered immigrants, those developing TB had a significantly longer delay to registration (mean difference [95% CI] 420 [259 to 580] days, p<0.001). Compared with age stratified ISC immigrants, time to registration was significantly longer for black Africans aged 16–35 years (mean difference 832 days, p<0.001). However, the proportion of preventable cases in registered immigrants was similar between ISC and black Africans (83.3% and 90.2%).Abstract P59 Table 1 Ethnicity TB cases / N (% of total) All cases Captured Missed Indian subcontinent 490 (55.4) 294 (62.6) 196 (47.3) Black African 222 (25.1) 92 (19.6) 130 (31.4) Conclusions Strategies to encourage early registration by new immigrants with a GP may improve utility of this resource for screening. However, greater emphasis on complementary strategies, including engagement of third sector organisations is needed, particularly for identifying black African immigrants at risk of TB.

P55 TB risk after new immigrant GP registration: a retrospective cohort analysis

Introduction Although 80% of all TB cases in the UK occur in foreign born persons, TB risk in the immigrant population is largely unknown due to uncertain estimates of migration. The evaluation of screening models to prevent immigrant TB depends on informed estimations of this risk. Objective To evaluate TB risk in a cohort of immigrants with new immigrant GP registration status (Flag-4) in Leicestershire; and to estimate efficacy of a screening model that uses Flag-4 registration and testing with interferon gamma release assays (IGRAs) for identifying latent infection with M tuberculosis (LTBI). Methods All Flag-4 registered immigrants between January 2000 and December 2010 were included and collated with TB notification data for the same period. TB cases arising in registered immigrants were included for estimation of case rate using Kaplan–Meier curves. Cumulative TB rates were expressed as time after UK entry and time after GP registration and compared between immigrant subgroups stratified by WHO incidence in country of origin (150–499/100 000 or 500+/100 000) and age group at time of registration (<16, 16–35 or =36 years). The number needed to screen was calculated using an overall prevalence estimate of 25% IGRA positivity, with all cases occurring in this subgroup. Results 564 cases were recorded in 34 764 immigrants. The median (IQR) observation was 2198 (982–3329) days after UK entry and 956 (358–1888) days after GP registration. There was no difference in risk with time after UK entry or GP registration and the TB rate rose linearly over 10 years. In our cohort, the 5-year cumulative TB rate was significantly higher for immigrants from regions with incidence of 150–499 than those from 500+. The TB rate was also significantly higher in adults than children, and highest in adults aged 16–35 years (Abstract P55 table 1). For this age band, the estimated number needed to screen (95% CI) with IGRAs to identify one immigrant developing TB in 5 years was 78.8 (73.2–85.2) persons.Abstract P55 Table 1 Five-year TB rate after GP registration in immigrant subgroups WHO incidence in country of origin Age at GP registration 150–499 500+ 0–15 16–35 36+ 5 year rate (SE)/100 000 person years 1421 (76.8) 1045 (193.7) 493 (98.7) 1691 (104) 1347 (151) Conclusions A new immigrant screening model using the Flag 4 GP registry and IGRA testing may be effective for identifying at-risk immigrants.