Pulmonary tuberculosis specificities in smokers

Discovery of serum biomarkers for diagnosis of tuberculosis by NMR metabolomics including cross-validation with a second cohort

Background

Tuberculosis (TB) is a disease with worldwide presence and a major cause of death in several developing countries. Current diagnostic methodologies often lack specificity and sensitivity, whereas a long time is needed to obtain a conclusive result.

Methods

In an effort to develop better diagnostic methods, this study aimed at the discovery of a biomarker signature for TB diagnosis using a Nuclear Magnetic Resonance based metabolomics approach. In this study, we acquired ¹H NMR spectra of blood serum samples of groups of healthy subjects, individuals with latent TB and of patients with pulmonary and extra-pulmonary TB. The resulting data were treated with uni- and multivariate statistical analysis.

Results

Six metabolites (inosine, hypoxanthine, mannose, asparagine, aspartate and glutamate) were validated by an independent cohort, all of them related with metabolic processes described as associated with TB infection.

Conclusion

The findings of the study are according with the WHO Target Product Profile recommendations for a triage test to rule-out active TB.

Clinico-radiological particularities of common pulmonary tuberculosis among smokers in Tunisia

INRODUCTION

Smoking and tuberculosis are two major public health issues worldwide, particularly in emerging countries. Currently, the relationship between these two scourges is well established.

AIM

Describe the clinical, radiological and progressive features of common pulmonary tuberculosis in smokers.

METHODS

Comparative study, carried out at the Pneumology department of the Hédi Chaker in Sfax, Tunisia, including 120 patients hospitalized for common pulmonary tuberculosis  from January 2014 to December 2016 and who completed their follow-ups for a minimum period of 2 years . The patients were divided into 2 groups: Group1 (G1) consisting of 60 smoking patients and Group 2 (G2) consisting of 60 non-smoking patients. To assess the severity of radiological lesions, we used the International Labour Organization classification for simple pneumoconiosis and the Brouet classification.

RESULTS

The mean age of the patients was comparable in the two groups with a predominance of male for G1 (91%) and female for G2 (70%). The smokers consulted later (113 days versus 60 days (p=0.023). Dyspnea, hemoptysis and chest pain were significantly more frequent in the smokers. The radiological lesions were more serious in smoking group. Bilateral lesions were more observed in smokers (58% vs 25% p = 0.004). A positive association was noted between the extent of radiological lesions, stage 3 and 4 according to the Brouet classification, and smoking status (p <0.001). Similarly for the International Labour Organization classification for simple pneumoconiosis , the radiological lesions were more severe (scores 6 - 15) in the smokers (p <0.001).Smoking was associated with poor adherence (p <0.008), prolonged anti-tuberculosis treatment (p <0.001), delayed RBK negativation in sputum (p <0.001), and more frequent reactivation of tuberculosis (p=0.001). After the diagnosis of CPT, 83% of patients continued to smoke at the same rate and only 7% of patients had quit smoking.

CONCLUSION

Smoking worsens CPT by making the clinical picture noisier, radiological lesions more aggressive, negativation of BK in sputum later, and reactivation of CPT more frequent.