Alternative sputum collection methods for diagnosis of childhood intrathoracic tuberculosis : a systematic literature review

Background Diagnosis of intrathoracic tuberculosis (ITB) is limited in children partly by their difficulty to produce sputum specimen. Objective To systematically review the detection yields of mycobacterial culture and Xpert MTB/RIF from induced sputum (IS), nasopharyngeal aspirate (NPA) and gastric aspirate (GA) in children with presumptive ITB. Design Pubmed, Embase and Biosis databases and grey literature were searched. Randomised controlled trials, cohort, cross-sectional or case control studies using IS, GA and NPA for diagnosis of ITB published between January 1990 and January 2018 were included. Data were extracted on study design, case definition of presumptive ITB, sample collection methods, outcome measures and results. Results 30 studies were selected, including 11 554 children. Detection yields for culture ranged between 1% and 30% for IS, 1% and 45% for GA and 4% and 24% for NPA. For Xpert MTB/RIF, it was between 2% and 17% for IS, 5% and 51% for GA and 3% and 8% for NPA. There was a tendency of better yields with IS when the pretest probability of ITB was low to moderate and with GA when it was high. Sampling a second specimen contributed for 6%-33% of the cumulative yield and combination of different methods significantly increase the detection yields. Conclusions Despite the important study heterogeneity, any of the specimen collection methods offers good potential to confirm childhood ITB. However, their operational challenges were poorly evaluated. In the absence of a sensitive non-sputum based test, only a minority of children with ITB can be confirmed

Splenectomy and chronic thromboembolic pulmonary hypertension

Background: An increased prevalence of splenectomy has been reported in patients with idiopathic pulmonary arterial hypertension. Examination of small pulmonary arteries from these subjects has revealed multiple thrombotic lesions, suggesting that thrombosis may contribute to this condition. Based on these findings, we hypothesised that splenectomy could be a risk factor for chronic thromboembolic pulmonary hypertension (CTEPH), a condition defined by the absence of thrombus resolution after acute pulmonary embolism that causes sustained obstruction of the pulmonary arteries and subsequent pulmonary hypertension. Methods: The medical history, clinical characteristics, thrombotic risk factors and haemodynamics of 257 patients referred for CTEPH between 1989 and 1999 were reviewed. In a case-control study the prevalence of splenectomy in patients with CTEPH was compared with that of patients evaluated during the same period for idiopathic pulmonary hypertension (n = 276) or for lung transplantation in other chronic pulmonary conditions (n = 180). Results: In patients with CTEPH, 8.6% (95% CI 5.2 to 12.0) had a history of splenectomy compared with 2.5% (95% CI 0.7 to 4.4) and 0.56% (95% CI 0 to 1.6) in cases of idiopathic pulmonary arterial hypertension and other chronic pulmonary conditions, respectively (p<0.01). Conclusion: Splenectomy may be a risk factor for chronic thromboembolic pulmonary hypertension