title: Changes in respiratory function impairment following the treatment of severe pulmonary tuberculosis - limitations for the underlying COPD detection.
abstract: BACKGROUND
  During the treatment phase of active pulmonary tuberculosis (PTB), respiratory function impairment is usually restrictive. This may become obstructive, as a PTB-associated airflow obstruction (AFO) or as a later manifestation of underlying COPD.
  
  
  OBJECTIVE
  The aim of the study was to examine the potential causes and risks for AFO development in PTB by exploring the aspects of spirometry limitations and clinical implications for the underlying COPD detection, taking into account various confounding factors.
  
  
  METHODS
  Prospective, nest case-control study on 40 new cases of PTB with initial restrictive respiratory function impairment, diagnosed and treated according to the directly observed treatment short course (DOTS) strategy.
  
  
  RESULTS
  From all observed patients, 37.5% of them developed AFO upon the completion of PTB treatment, with significantly increased average of forced vital capacity (%) (P<0.01). Their changes in forced expiratory volume in the first second (%) during the PTB treatment were strongly associated with the air pollution exposure in living (0.474%-20.971% for 95% confidence interval [CI]; P=0.041) and working environments (3.928%-20.379% for 95% CI; P=0.005), initial radiological extent of PTB lesions (0.018%-0.700% for 95% CI; P=0.047), leukocyte count (0.020%-1.328% for 95% CI; P=0.043), and C-reactive protein serum level (0.046%-0.205% for 95% CI; P=0.003) compared to the other patients. The multivariate logistic regression analysis model shows initial radiological extent of pulmonary tuberculosis lesions (OR 1.01-1.05 for 95% CI; P=0.02) and sputum conversion rate on culture (OR 1.02-1.68 for 95% CI; P=0.04) as the most significant predictors for the risk of AFO development.
  
  
  CONCLUSIONS
  AFO upon PTB treatment is a common manifestation of underlying COPD, which mostly occurs later, during the reparative processes in active PTB, even in the absence of major risk factors, such as cigarette smoking and biomass fuel dust exposure. Initial spirometry testing in patients with active PTB is not a sufficient and accurate approach in the detection of underlying COPD, which may lead to their further potential health deterioration.
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, University of Nis, Nis, Republic of Serbia; Clinic for Lung Diseases, Clinical Centre of Nis, Nis, Republic of Serbia.
authors.forename: Milan
authors.initials: M
authors.lastname: Radovic
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, University of Nis, Nis, Republic of Serbia; Clinic for Lung Diseases, Clinical Centre of Nis, Nis, Republic of Serbia.
authors.forename: Lidija
authors.initials: L
authors.lastname: Ristic
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, University of Nis, Nis, Republic of Serbia; Clinic for Lung Diseases, Clinical Centre of Nis, Nis, Republic of Serbia.
authors.forename: Zorica
authors.initials: Z
authors.lastname: Ciric
authors.affiliation: Clinic for Gastroenterology and Hepatology, Clinical Centre of Nis, Nis, Republic of Serbia.
authors.forename: Violeta
authors.initials: V
authors.lastname: Dinic-Radovic
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, University of Nis, Nis, Republic of Serbia; Clinic for Lung Diseases, Clinical Centre of Nis, Nis, Republic of Serbia.
authors.forename: Ivana
authors.initials: I
authors.lastname: Stankovic
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, University of Nis, Nis, Republic of Serbia; Clinic for Lung Diseases, Clinical Centre of Nis, Nis, Republic of Serbia.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Pejcic
authors.affiliation: Department of Internal Medicine, Faculty of Medicine, University of Nis, Nis, Republic of Serbia; Clinic for Lung Diseases, Clinical Centre of Nis, Nis, Republic of Serbia.
authors.forename: Milan
authors.initials: M
authors.lastname: Rancic
authors.affiliation: Public Health Institute Nis, Nis, Republic of Serbia.
authors.forename: Dragan
authors.initials: D
authors.lastname: Bogdanovic
mesh_terms: D000328:Adult; D000368:Aged; D000402:Airway Obstruction / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D000995:Antitubercular Agents / Q000627:therapeutic use*; D016022:Case-Control Studies; D023801:Directly Observed Therapy; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016015:Logistic Models; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D015203:Reproducibility of Results; D012307:Risk Factors; D012720:Severity of Illness Index; D013147:Spirometry; D016896:Treatment Outcome; D014397:Tuberculosis, Pulmonary / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology; D014797:Vital Capacity
chemical_list: D000995:Antitubercular Agents
keywords: lung diseases; obstructive; pulmonary; respiratory function tests; tuberculosis