Pulmonary functional assessment: longitudinal study after treatment of pulmonary tuberculosis

Unveiling Silent Consequences: Impact of Pulmonary Tuberculosis on Lung Health and Functional Wellbeing after Treatment

Background: Pulmonary tuberculosis (TB) remains a major public health issue in India, with high incidence and mortality. The current literature on post-TB sequelae functional defects focuses heavily on spirometry, with conflicting obstruction vs. restriction data, lacks advanced statistical analysis, and has insufficient data on diffusion limitation and functional impairment. Objective: This study aimed to thoroughly evaluate post-tubercular sequelae after treatment, assessing chest radiology, spirometry, diffusing capacity, and exercise capacity. Methods: A total of 85 patients were studied at a university teaching hospital in Mysuru. The data collected included characteristics, comorbidities, smoking history, and respiratory symptoms. The investigations included spirometry, DLCO, chest X-rays with scoring, and 6MWT. Results: Of the patients, 70% had abnormal X-rays post-treatment, correlating with reduced lung function. Additionally, 70% had impaired spirometry with obstructive/restrictive patterns, and 62.2% had reduced DLCO, with females at higher risk. Smoking increased the risk of sequelae. Conclusions: Most patients had residual radiological/lung function abnormalities post-treatment. Advanced analyses provide insights into obstructive vs. restrictive defects. Ongoing research should explore pathogenetic mechanisms and therapeutic modalities to minimize long-term post-TB disability.

Diffusing capacity as an independent predictor of acute exacerbations in chronic obstructive pulmonary disease

A weak correlation between diffusing capacity of the lung for carbon monoxide (DLCO) and emphysema has been reported. This study investigated whether impaired DLCO in chronic obstructive pulmonary disease (COPD) is associated with increased risk of acute exacerbation independent of the presence or extent of emphysema. This retrospective cohort study included patients with COPD between January 2004 and December 2019. The participants were divided into four groups based on visually detected emphysema and impaired DLCO. Among 597 patients with COPD, 8.5% had no emphysema and impaired DLCO whereas 36.3% had emphysema without impaired DLCO. Among the four groups, patients with impaired DLCO and emphysema showed a higher risk of moderate-to-severe or severe exacerbation than those with normal DLCO. Impaired DLCO was an independent risk factor for severe exacerbation (hazard ratio, 1.524 [95% confidence interval 1.121-2.072]), whereas the presence of emphysema was not. The risk of moderate-to-severe or severe exacerbation increases with the severity of impaired DLCO. After propensity-score matching for the extent of emphysema, impaired DLCO was significantly associated with a higher risk of moderate-to-severe (p = 0.041) or severe exacerbation (p = 0.020). In patients with COPD and heterogeneous parenchymal abnormalities, DLCO can be considered an independent biomarker of acute exacerbation.

Analysis of Clinical Characteristics and Risk Factors for Drug Resistance in Newly-Treated Patients with Pulmonary Tuberculosis Complicated with Chronic Obstructive Pulmonary Disease

Objective

To analyze the clinical characteristics and risk factors of drug resistance of newly-treated chronic obstructive pulmonary disease (COPD) complicated pulmonary tuberculosis (PTB).

Methods

A total of 489 newly-treated PTB patients admitted to Beijing Geriatric hospital were retrospectively enrolled in this study. Of these, 138 patients with COPD were allocated to the study group, and the remaining 351 patients without COPD were allocated to the control group. The baseline information, clinical characteristics of PTB and drug resistance of Mycobacterium tuberculosis were compared between the two groups. Logistic regression was used to explore the correlation between drug resistance and COPD complications.

Results

Patients complicated with COPD had a higher proportion of respiratory failure, cough, fever and night sweats, chest short breath, and emaciation between the study group and the control group (P<0.05). In terms of medical history, patients complicated with COPD also had a higher proportion of childhood TB history, cough, tuberculosis exposure rate, dust exposure rate, and malnutrition (P<0.05). There were significantly more patients with pulmonary cavities and a delayed diagnosis of TB in the study group than in the control group (P<0.05). The single drug resistance rates of isoniazid, ethambutol, rifampicin, pyrazinamide, and rifapentine, and drug resistance with any two or more drugs in the study group were significantly higher than those in the control group (P<0.05). Multivariate Logistic regression analysis showed that smoking, extrapulmonary tuberculosis, tuberculosis exposure history, malnutrition, pulmonary cavity, and delayed TB diagnosis were risk factors for drug resistance in newly-treated COPD complicated PTB patients.

Conclusion

The symptoms of COPD complicated PTB were more serious. Smoking history, extrapulmonary tuberculosis, tuberculosis exposure history, malnutrition, pulmonary cavity, and delayed diagnosis of tuberculosis were risk factors for TB resistance in these patients.