Identifying neonates at risk for post-discharge mortality in Dar es Salaam, Tanzania, and Monrovia, Liberia: Derivation and internal validation of a novel risk assessment tool

INTRODUCTION

The immediate period after hospital discharge carries a large burden of childhood mortality in sub-Saharan Africa. Our objective was to derive and internally validate a risk assessment tool to identify neonates discharged from the neonatal ward at risk for 60-day post-discharge mortality.

METHODS

We conducted a prospective observational cohort study of neonates discharged from Muhimbili National Hospital in Dar es Salaam, Tanzania, and John F Kennedy Medical Centre in Monrovia, Liberia. Research staff called caregivers to ascertain vital status up to 60 days after discharge. We conducted multivariable logistic regression analyses with best subset selection to identify socioeconomic, demographic, clinical, and anthropometric factors associated with post-discharge mortality. We used adjusted log coefficients to assign points to each variable and internally validated our tool with bootstrap validation with 500 repetitions.

RESULTS

There were 2344 neonates discharged and 2310 (98.5%) had post-discharge outcomes available. The median (IQR) age at discharge was 8 (4, 15) days; 1238 (53.6%) were male. In total, 71 (3.1%) died during follow-up (26.8% within 7 days of discharge). Leaving against medical advice (adjusted OR [aOR] 5.62, 95% CI 2.40 to 12.10) and diagnosis of meconium aspiration (aOR 6.98, 95% CI 1.69 to 21.70) conferred the greatest risk for post-discharge mortality. The risk assessment tool included nine variables (total possible score=63) and had an optimism corrected area under the receiver operating characteristic curve of 0.77 (95% CI 0.75 to 0.80). A score of ≥6 was most optimal (sensitivity 68.3% [95% CI 64.8% to 71.5%], specificity 72.1% [95% CI 71.5% to 72.7%]).

CONCLUSIONS

A small number of factors predicted all-cause, 60-day mortality after discharge from neonatal wards in Tanzania and Liberia. After external validation, this risk assessment tool may facilitate clinical decision making for eligibility for discharge and the direction of resources to follow-up high risk neonates.

Predictive value of clinician impression for readmission and postdischarge mortality among neonates and young children in Dar es Salaam, Tanzania and Monrovia, Liberia

BACKGROUND

There are no validated clinical decision aids to identify neonates and young children at risk of hospital readmission or postdischarge mortality in sub-Saharan Africa, leaving the decision to discharge a child to a clinician's impression. Our objective was to determine the precision of clinician impression to identify neonates and young children at risk for readmission and postdischarge mortality.

METHODS

We conducted a survey study nested in a prospective observational cohort of neonates and children aged 1-59 months followed 60 days after hospital discharge from Muhimbili National Hospital in Dar es Salaam, Tanzania or John F. Kennedy Medical Center in Monrovia, Liberia. Clinicians who discharged each enrolled patient were surveyed to determine their perceived probability of the patient's risk of 60-day hospital readmission or postdischarge mortality. We calculated the area under the precision-recall curve (AUPRC) to determine the precision of clinician impression for both outcomes.

RESULTS

Of 4247 discharged patients, 3896 (91.7%) had available clinician surveys and 3847 (98.7%) had 60-day outcomes available: 187 (4.8%) were readmitted and 120 (3.1%) died within 60 days of hospital discharge. Clinician impression had poor precision in identifying neonates and young children at risk of hospital readmission (AUPRC: 0.06, 95% CI: 0.04 to 0.08) and postdischarge mortality (AUPRC: 0.05, 95% CI: 0.03 to 0.08). Patients for whom clinicians attributed inability to pay for future medical treatment as the reason for risk for unplanned hospital readmission had 4.76 times the odds hospital readmission (95% CI: 1.31 to 17.25, p=0.02).

CONCLUSIONS

Given the poor precision of clinician impression alone to identify neonates and young children at risk of hospital readmission and postdischarge mortality, validated clinical decision aids are needed to aid in the identification of young children at risk for these outcomes.

A Prospective, observational cohort study to identify neonates and children at risk of postdischarge mortality in Dar es Salaam, Tanzania and Monrovia, Liberia: the PPDM study protocol

INTRODUCTION

Over half of the 5 million annual deaths among children aged 0-59 months occur in sub-Saharan Africa. The period immediately after hospitalisation is a vulnerable time in the life of a child in sub-Saharan Africa as postdischarge mortality rates are as high as 1%-18%. Identification of neonates and children who are at highest risk for postdischarge mortality may allow for the direction of interventions to target patients at highest risk.

METHODS AND ANALYSIS

The Predicting Post-Discharge Mortality study is a prospective, observational study being conducted at Muhimbili National Hospital (Dar es Salaam, Tanzania) and John F. Kennedy Medical Center (Monrovia, Liberia). The aim is to derive and validate two, age population specific, clinical prediction rules for the identification of neonates (n=2000) and children aged 1-59 months (n=2000) at risk for all-cause mortality within 60 days of discharge from the neonatal intensive care unit or paediatric ward. Caregivers of participants will receive phone calls 7, 14, 30, 45 and 60 days after discharge to assess vital status. Candidate predictor variables will include demographic, anthropometric and clinical factors. Elastic net regression will be used to derive the clinical prediction rules. Bootstrapped selection with repetitions will be used for internal validation. Planned secondary analyses include the external validation of existing clinical prediction models, determination of clinicians' ability to identify neonates and children at risk of postdischarge mortality at discharge, analysis of factors associated with hospital readmission and unplanned clinic visits and description of health-seeking behaviours in the postdischarge period.

ETHICS AND DISSEMINATION

This study received ethical clearance from the Tanzania National Institute of Medical Research, Muhimbili University of Health and Allied Sciences, the John F. Kennedy Medical Center Institutional Review Board, and the Boston Children's Hospital Institutional Review Board. Findings will be disseminated at scientific conferences and as peer-reviewed publications.

Where there is no local author: a network bibliometric analysis of authorship parasitism among research conducted in sub-Saharan Africa

INTRODUCTION

Authorship parasitism (ie, no authors affiliated with the country in which the study took place) occurs frequently in research conducted in low-income and middle-income countries, despite published recommendations defining authorship criteria. The objective was to compare characteristics of articles exhibiting authorship parasitism in sub-Saharan Africa to articles with author representation from sub-Saharan African countries.

METHODS

A bibliometric review of articles indexed in PubMed published from January 2014 through December 2018 reporting research conducted in sub-Saharan Africa was performed. Author affiliations were assigned to countries based on regular expression algorithms. Choropleth maps and network diagrams were created to determine where authorship parasitism occurred, and multivariable logistic regression was used to determine associated factors.

RESULTS

Of 32 061 articles, 14.8% (n=4754) demonstrated authorship parasitism, which was most common among studies from Somalia (n=175/233, 75.1%) and Sao Tome and Principe (n=20/28, 71.4%). Authors affiliated with USA and UK institutions were most commonly involved in articles exhibiting authorship parasitism. Authorship parasitism was more common in articles: published in North American journals (adjusted OR (aOR) 1.26, 95% CI 1.07 to 1.50) than in sub-Saharan African journals, reporting work from multiple sub-Saharan African countries (aOR 8.41, 95% CI 7.30 to 9.68) compared with work from upper-middle income sub-Saharan African countries, with <5 authors (aOR 14.46, 95% CI 12.81 to 16.35) than >10 authors, and was less common in articles published in French (aOR 0.60, 95% CI 0.41 to 0.85) than English.

CONCLUSIONS

Authorship parasitism was common in articles reporting research conducted in sub-Saharan Africa. There were reliable predictors of authorship parasitism. Investigators and institutions in high-income countries, as well as funding agencies and journals should promote research from sub-Saharan Africa, including its publication, in a collaborative and equitable manner.

Impact of the introduction of pneumococcal conjugate vaccination on invasive pneumococcal disease and pneumonia in The Gambia: 10 years of population-based surveillance

Background

The Gambia introduced seven-valent pneumococcal conjugate vaccine (PCV7) in August 2009, followed by PCV13 in May, 2011, using a schedule of three primary doses without a booster dose or catch-up immunisation. We aimed to assess the long-term impact of PCV on disease incidence.

Methods

We did 10 years of population-based surveillance for invasive pneumococcal disease (IPD) and WHO defined radiological pneumonia with consolidation in rural Gambia. The surveillance population included all Basse Health and Demographic Surveillance System residents aged 2 months or older. Nurses screened all outpatients and inpatients at all health facilities using standardised criteria for referral. Clinicians then applied criteria for patient investigation. We defined IPD as a compatible illness with isolation of Streptococcus pneumoniae from a normally sterile site (cerebrospinal fluid, blood, or pleural fluid). We compared disease incidence between baseline (May 12, 2008–May 11, 2010) and post-vaccine years (2016–2017), in children aged 2 months to 14 years, adjusting for changes in case ascertainment over time.

Findings

We identified 22 728 patients for investigation and detected 342 cases of IPD and 2623 cases of radiological pneumonia. Among children aged 2–59 months, IPD incidence declined from 184 cases per 100 000 person-years to 38 cases per 100 000 person-years, an 80% reduction (95% CI 69–87). Non-pneumococcal bacteraemia incidence did not change significantly over time (incidence rate ratio 0·88; 95% CI, 0·64–1·21). We detected zero cases of vaccine-type IPD in the 2–11 month age group in 2016–17. Incidence of radiological pneumonia decreased by 33% (95% CI 24–40), from 10·5 to 7·0 per 1000 person-years in the 2–59 month age group, while pneumonia hospitalisations declined by 27% (95% CI 22–31). In the 5–14 year age group, IPD incidence declined by 69% (95% CI −28 to 91) and radiological pneumonia by 27% (95% CI −5 to 49).

Interpretation

Routine introduction of PCV13 substantially reduced the incidence of childhood IPD and pneumonia in rural Gambia, including elimination of vaccine-type IPD in infants. Other low-income countries can expect substantial impact from the introduction of PCV13 using a schedule of three primary doses.

Funding

Gavi, The Vaccine Alliance; Bill & Melinda Gates Foundation; UK Medical Research Council; Pfizer Ltd.

Implementation and 8-year follow-up of an uninterrupted oxygen supply system in a hospital in The Gambia

SETTING: A 42-bed hospital operated by the Medical Research Council (MRC) Unit in The Gambia.

OBJECTIVE: To devise, test and evaluate a cost-efficient uninterrupted oxygen system in the MRC Hospital.

DESIGN: Oxygen cylinders were replaced with oxygen concentrators as the primary source of oxygen. An uninterruptable power supply (UPS) ensured continuity of power. Hospital staff were trained on the use of the new system. Eight years post-installation, an analysis of concentrator maintenance needs and costs was conducted and user feedback obtained to assess the success of the system.

RESULTS: The new system saved at least 51% of oxygen supply costs compared to cylinders, with savings likely to have been far greater due to cylinder leakages. Users indicated that the system is easier to use and more reliable, although technical support and staff training are still needed.

CONCLUSION: Oxygen concentrators offer long-term cost savings and an improved user experience compared to cylinders; however, some technical support and maintenance are needed to upkeep the system. A UPS dedicated to oxygen concentrators is an appropriate solution for settings where power interruptions are frequent but short in duration. This approach can be a model for health systems in settings with similar infrastructure.

Impact of the introduction of pneumococcal conjugate vaccination on pneumonia in The Gambia: population-based surveillance and case-control studies

BACKGROUND

Pneumococcal conjugate vaccines (PCVs) are used in many low-income countries but their impact on the incidence of pneumonia is unclear. The Gambia introduced PCV7 in August, 2009, and PCV13 in May, 2011. We aimed to measure the impact of the introduction of these vaccines on pneumonia incidence.

METHODS

We did population-based surveillance and case-control studies. The primary endpoint was WHO-defined radiological pneumonia with pulmonary consolidation. Population-based surveillance was for suspected pneumonia in children aged 2-59 months (minimum age 3 months in the case-control study) between May 12, 2008, and Dec 31, 2015. Surveillance for the impact study was limited to the Basse Health and Demographic Surveillance System (BHDSS), whereas surveillance for the case-control study included both the BHDSS and Fuladu West Health and Demographic Surveillance System. Nurses screened all outpatients and inpatients at all health facilities in the surveillance area using standardised criteria for referral to clinicians in Basse and Bansang. These clinicians recorded clinical findings and applied standardised criteria to identify patients with suspected pneumonia. We compared the incidence of pneumonia during the baseline period (May 12, 2008, to May 11, 2010) and the PCV13 period (Jan 1, 2014, to Dec 31, 2015). We also investigated the effectiveness of PCV13 using case-control methods between Sept 12, 2011, and Sept 31, 2014. Controls were aged 90 days or older, and were eligible to have received at least one dose of PCV13; cases had the same eligibility criteria with the addition of having WHO-defined radiological pneumonia.

FINDINGS

We investigated 18 833 children with clinical pneumonia and identified 2156 cases of radiological pneumonia. Among children aged 2-11 months, the incidence of radiological pneumonia fell from 21·0 cases per 1000 person-years in the baseline period to 16·2 cases per 1000 person-years (23% decline, 95% CI 7-36) in 2014-15. In the 12-23 month age group, radiological pneumonia decreased from 15·3 to 10·9 cases per 1000 person-years (29% decline, 12-42). In children aged 2-4 years, incidence fell from 5·2 to 4·1 cases per 1000 person-years (22% decline, 1-39). Incidence of all clinical pneumonia increased by 4% (-1 to 8), but hospitalised cases declined by 8% (3-13). Pneumococcal pneumonia declined from 2·9 to 1·2 cases per 1000 person-years (58% decline, 22-77) in children aged 2-11 months and from 2·6 to 0·7 cases per 1000 person-years (75% decline, 47-88) in children aged 12-23 months. Hypoxic pneumonia fell from 13·1 to 5·7 cases per 1000 person-years (57% decline, 42-67) in children aged 2-11 months and from 6·8 to 1·9 cases per 1000 person-years (72% decline, 58-82) in children aged 12-23 months. In the case-control study, the best estimate of the effectiveness of three doses of PCV13 against radiological pneumonia was an adjusted odds ratio of 0·57 (0·30-1·08) in children aged 3-11 months and vaccine effectiveness increased with greater numbers of doses (p=0·026). The analysis in children aged 12 months and older was underpowered because there were few unvaccinated cases and controls.

INTERPRETATION

The introduction of PCV in The Gambia was associated with a moderate impact on the incidence of radiological pneumonia, a small reduction in cases of hospitalised pneumonia, and substantial reductions of pneumococcal and hypoxic pneumonia in young children. Low-income countries that introduce PCV13 with reasonable coverage can expect modest reductions in hospitalised cases of pneumonia and a marked impact on the incidence of severe childhood pneumonia.

FUNDING

GAVI's Pneumococcal vaccines Accelerated Development and Introduction Plan, Bill & Melinda Gates Foundation, and UK Medical Research Council.

Childhood pneumonia and crowding, bed-sharing and nutrition: a case-control study from The Gambia

SETTING

Greater Banjul and Upper River Regions, The Gambia.

OBJECTIVE

To investigate tractable social, environmental and nutritional risk factors for childhood pneumonia.

DESIGN

A case-control study examining the association of crowding, household air pollution (HAP) and nutritional factors with pneumonia was undertaken in children aged 2-59 months: 458 children with severe pneumonia, defined according to the modified WHO criteria, were compared with 322 children with non-severe pneumonia, and these groups were compared to 801 neighbourhood controls. Controls were matched by age, sex, area and season.

RESULTS

Strong evidence was found of an association between bed-sharing with someone with a cough and severe pneumonia (adjusted OR [aOR] 5.1, 95%CI 3.2-8.2, P < 0.001) and non-severe pneumonia (aOR 7.3, 95%CI 4.1-13.1, P < 0.001), with 18% of severe cases estimated to be attributable to this risk factor. Malnutrition and pneumonia had clear evidence of association, which was strongest between severe malnutrition and severe pneumonia (aOR 8.7, 95%CI 4.2-17.8, P < 0.001). No association was found between pneumonia and individual carbon monoxide exposure as a measure of HAP.

CONCLUSION

Bed-sharing with someone with a cough is an important risk factor for severe pneumonia, and potentially tractable to intervention, while malnutrition remains an important tractable determinant.

Is the absolute requirement for informed consent before HIV testing a barrier to public health? A case report and management challenges

Clinicians in sub-Saharan Africa are faced with a major challenge of parental refusal to test their children for HIV. We present a case of a nine-month-old child with a clinical presentation suggestive of HIV infection whose mother persistently declined HIV testing of the child or herself. The case illustrates the difficulties faced by the clinicians caring for the child in an isolated location in West Africa. While not eliminating these difficulties, an opt-out approach to paediatric HIV testing in sub-Saharan Africa may increase the proportion of children who access treatment when they need it, particularly when this is backed by the development of more effective national and regional clinical and legislative frameworks for HIV testing in children.

Management of persistent purulent pericarditis using streptokinase for intrapericardial fibrinolysis

Purulent pericarditis (PP) is a very serious condition with almost 100% mortality if untreated. Intrapericardial fibrinolysis is a preferred alternative to pericardectomy in the treatment of persistent PP, but there are no consensus guidelines on the standard protocol for this procedure in children. A 9-year-old boy was referred to the Medical Research Council Unit in The Gambia (MRC). He had been unwell for 18 days with a high continuous fever, cough, fast breathing, and dyspnoea on exertion. Prior to referral he had been treated for malaria and pneumonia with no improvement. At the MRC, he was diagnosed with purulent pericarditis caused by Staphylococcus aureus and after admission he was managed for 4 weeks with intravenous antibiotics, pericardial aspirations followed by saline lavage of the pericardium and intrapericardial antibiotic instillation. Despite these measures, massive re-accumulation of the purulent pericardial effusion continued. Once daily intrapericardial instillation of streptokinase at a dose of 18,000 i.u/kg diluted in 50 ml of normal saline, and saline washout of the pericardium after 2 hours was commenced on the 29th day of admission, in addition to the antibiotics. This technique of fibrinolysis employed for 2 days was effective in managing the persistent purulent pericarditis when pericardial aspiration and intravenous and intrapericardial antibiotics failed.

Etiology of severe childhood pneumonia in the Gambia, West Africa, determined by conventional and molecular microbiological analyses of lung and pleural aspirate samples

Molecular analyses of lung aspirates from Gambian children with severe pneumonia detected pathogens more frequently than did culture and showed a predominance of bacteria, principally Streptococcuspneumoniae, >75% being of serotypes covered by current pneumococcal conjugate vaccines. Multiple pathogens were detected frequently, notably Haemophilus influenzae (mostly nontypeable) together with S. pneumoniae.

Discovery and validation of biomarkers to guide clinical management of pneumonia in African children

Lipocalin 2 distinguishes severe and bacterial pneumonia from nonsevere and nonbacterial pneumonia with a high level of precision. The clinical impact of this biomarker requires large-scale clinical evaluation.

Background. Pneumonia is the leading cause of death in children globally. Clinical algorithms remain suboptimal for distinguishing severe pneumonia from other causes of respiratory distress such as malaria or distinguishing bacterial pneumonia and pneumonia from others causes, such as viruses. Molecular tools could improve diagnosis and management.

Methods. We conducted a mass spectrometry–based proteomic study to identify and validate markers of severity in 390 Gambian children with pneumonia (n = 204) and age-, sex-, and neighborhood-matched controls (n = 186). Independent validation was conducted in 293 Kenyan children with respiratory distress (238 with pneumonia, 41 with Plasmodium falciparum malaria, and 14 with both). Predictive value was estimated by the area under the receiver operating characteristic curve (AUC).

Results. Lipocalin 2 (Lpc-2) was the best protein biomarker of severe pneumonia (AUC, 0.71 [95% confidence interval, .64–.79]) and highly predictive of bacteremia (78% [64%–92%]), pneumococcal bacteremia (84% [71%–98%]), and “probable bacterial etiology” (91% [84%–98%]). These results were validated in Kenyan children with severe malaria and respiratory distress who also met the World Health Organization definition of pneumonia. The combination of Lpc-2 and haptoglobin distinguished bacterial versus malaria origin of respiratory distress with high sensitivity and specificity in Gambian children (AUC, 99% [95% confidence interval, 99%–100%]) and Kenyan children (82% [74%–91%]).

Conclusions. Lpc-2 and haptoglobin can help discriminate the etiology of clinically defined pneumonia and could be used to improve clinical management. These biomarkers should be further evaluated in prospective clinical studies.

The effectiveness of conjugate Haemophilus influenzae type B vaccine in The Gambia 14 years after introduction

BACKGROUND

The Gambia was the first country in Africa to introduce conjugate Haemophilus influenzae type b (Hib) vaccine, which, as in other developing countries but unlike industrialized countries, is delivered as a 3-dose primary series with no booster. This study assessed its effectiveness 14 years after introduction.

METHODS

Using methods standardized during >20 years in the study site, clinical and microbiological surveillance for invasive Hib disease (primarily meningitis) in the Western Region of The Gambia from 2007 to 2010 was complemented with studies of Hib carriage in children aged 1 to <2 years, Hib antibody levels in children aged <5 years, and Hib vaccine coverage and timing in children aged 1 to <2 years.

RESULTS

The incidence of Hib meningitis remained low (averaging 1.3 per 100 000 children aged <5 years annually), as did the Hib oropharyngeal carriage rate (0.9%). Hib antibody levels were protective in >99% of those surveyed, albeit with lower titers in older children; and coverage of conjugate Hib vaccination was high (91% having 3 doses at 1-2 years of age) using a schedule that was delivered at median ages of 2.6 months, 4.3 months, and 6 months for the first, second, and third doses, respectively.

CONCLUSIONS

Conjugate Hib vaccine was delivered on time in a 3-dose primary series without booster to a high proportion of eligible children and this was associated with effective disease control up to 14 years after introduction. It is important that surveillance continues in this first African country to introduce the vaccine to determine if effective control persists or if a booster dose becomes necessary as has been the case in industrialized countries.

Incidence of Haemophilus influenzae type b disease in The Gambia 14 years after introduction of routine Haemophilus influenzae type b conjugate vaccine immunization

OBJECTIVE

Haemophilus influenzae type b (Hib) conjugate vaccine was first introduced in Africa in The Gambia in 1997 as a primary 3-dose course in infancy with no booster, and was followed by the disappearance of invasive Hib disease by 2002. A cluster of cases detected non-systematically in post-infant children in 2005-2006 raised the question of the need for a booster dose. The objective of this study was to determine the incidence of invasive Hib disease in Gambian children 14 years after the introduction of Hib conjugate vaccine.

STUDY DESIGN

This hospital-based clinical and microbiological Hib disease surveillance in 3 hospitals in the western region of The Gambia was undertaken between October 2007 and December 2010 applying the same methods used in a previous Hib vaccine effectiveness study in 1997-2002.

RESULTS

The annual incidences of Hib meningitis and all invasive Hib disease in children aged <5 years remained below 5 cases per 100,000 children during 2008-2010. The median age of patients with any invasive Hib disease was 5 months.

CONCLUSION

Hib conjugate vaccination as a primary 3-dose course in The Gambia remains highly effective in controlling invasive Hib disease, and current data do not support the introduction of a booster dose.

The exposure of infants and children to carbon monoxide from biomass fuels in The Gambia: a measurement and modeling study

Smoke from biomass fuels is a risk factor for pneumonia, the leading cause of child death worldwide. Although particulate matter (PM) is the metric of choice for studying the health effects of biomass smoke, measuring children's PM exposure is difficult. Carbon monoxide (CO), which is easier to measure, can be used as a proxy for PM exposure. We measured the exposure of children ≤ 5 years of age in The Gambia to CO using small, passive, color stain diffusion tubes. We conducted multiple CO measurements on a subset of children to measure day-to-day exposure variability. Usual CO exposure was modeled using a mixed effects model, which also included individual and household level exposure predictors. Mean measured CO exposure for 1181 children (n=2263 measurements) was 1.04 ± 1.46 p.p.m., indicating that the Gambian children in this study on average have a relatively low CO exposure. However, 25% of children had exposures of 1.3 p.p.m. or higher. CO exposure was higher during the rainy months (1.33 ± 1.62 p.p.m.). Burning insect coils, using charcoal, and measurement done in the rainy season were associated with higher exposure. A parsimonious model with fuel, season, and other PM sources as covariates explained 39% of between-child variation in exposure and helped remove within-child variability.

Highly accurate diagnosis of pleural tuberculosis by immunological analysis of the pleural effusion

Pleural TB is notoriously difficult to diagnose due to its paucibacillary nature yet it is the most common cause of pleural effusions in TB endemic countries such as The Gambia. We identified both cellular and soluble biomarkers in the pleural fluid that allowed highly accurate diagnosis of pleural TB compared to peripheral blood markers. Multi-plex cytokine analysis on unstimulated pleural fluid showed that IP-10 resulted in a positive likelihood ratio (LR) of 9.6 versus 2.8 for IFN-γ; a combination of IP-10, IL-6 and IL-10 resulted in an AUC of 0.96 and positive LR of 10. A striking finding was the significantly higher proportion of PPD-specific IFN-γ+TNF-α+ cell population (PPD-IGTA) in the pleural fluid compared to peripheral blood of TB subjects. Presence of this pleural PPD-IGTA population resulted in 95% correct classification of pleural TB disease with a sensitivity of 95% and specificity of 100%. These data suggest that analysis of the site of infection provides superior diagnostic accuracy compared to peripheral blood for pleural TB, likely due to the sequestration of effector cells at this acute stage of disease.

Transthoracic lung aspiration for the aetiological diagnosis of pneumonia: 25 years of experience from The Gambia

Pneumonia remains the leading cause of death in young children worldwide. Global pneumonia control depends on a good understanding of the aetiology of pneumonia. Percutaneous transthoracic aspiration culture is much more sensitive than blood culture in identifying the aetiological agents of pneumonia. However, the procedure is not widely practised because of lack of familiarity with it and concerns about potential adverse events. We review the diagnostic usefulness and safety of this procedure over 25 years of its use in research and routine practice at the UK Medical Research Council (MRC), The Gambia, and give a detailed description of the procedure itself. Published materials were identified from the MRC's publication database and systematic searches using the PubMed/Medline and Google search engines. Data from a current pneumonia aetiology study in the unit are included together with clinical experience of staff practising at the unit over the period covered in this review. A minimum of 500 lung aspirates were performed over the period of review. Lung aspiration produces a greater yield of diagnostic bacterial isolates than blood culture. It is especially valuable clinically when pathogens not covered by standard empirical antibiotic treatment, such as Mycobacterium tuberculosis and Staphylococcus aureus, are identified. There have been no deaths following the procedure in our setting and a low rate of other complications, all transient. Lung aspiration is currently the most sensitive method for diagnosing pneumonia in children. With appropriate training and precautions it can be safely used for routine diagnosis in suitable referral hospitals.