title: Non conversion of sputum smears in new smear positive pulmonary tuberculosis patients in Yaoundé, Cameroon.
abstract: OBJECTIVE
  To identify clinical, radiological and microbiological factors associated with the non conversion of sputum smears in new smear positive cases of pulmonary tuberculosis after two months of treatment and to evaluate the influence of non-smear conversion on treatment outcomes.
  
  
  METHODS
  A prospective cohort study.
  
  
  METHODS
  Tuberculosis centre of Hôpital Jamot in Yaoundé- Cameroon from April 2006 to September 2007.
  
  
  METHODS
  A total of 413 patients were studied.
  
  
  METHODS
  Sputum smear status at two months of treatment, favourable treatment outcome (cured, treatment completed), unfavourable treatment outcome (death, treatment failure, default from treatment) and transferred out.
  
  
  RESULTS
  A total of 413 patients were studied; There were 234 (56.8%) males and 178 (43.2%) females with a mean age of 33 years (range 9.80 years). Sputum smears did not convert in 55 (13.4%) patients at the end of two months of treatment. Logistic regression analysis showed that age above or equal to 40 years (OR=2.716, 95% CI:1.412-5.223, p=0.003), and a bacillary load of 3+ on pre-treatment sputum smears (OR=1.955; 95% CI: 1.039-3.68, p=0.037) were significantly associated with non conversion of sputum smears at the end of two months of treatment. Persistent positive smears at the end of two months of treatment were significantly associated with unfavourable treatment outcomes (p=0.025) especially default during the course of treatment.
  
  
  CONCLUSIONS
  In Yaoundé, Cameroon, non conversion of positive sputum smears in new patients with pulmonary tuberculosis at the end of two months of treatment is associated with an unfavourable outcome particularly defaulting later in the course of treatment. Non conversion of sputum smears at two months of treatment is significantly associated with age above or equal to 40 years and the presence of numerous bacilli (3+) on pre-treatment sputum smears. Patients with these factors who do not smear convert after two months of treatment should be given a fully supervised treatment for the entire duration of therapy so as to prevent in particular treatment default.
authors.affiliation: Department of Internal Medicine, Faculty of Medicine and Biomedical Sciences, University of Yaoundé, Yaoundé, Cameroon.
authors.forename: C
authors.initials: C
authors.lastname: Kuaban
authors.forename: R
authors.initials: R
authors.lastname: Bame
authors.forename: L
authors.initials: L
authors.lastname: Mouangue
authors.forename: S
authors.initials: S
authors.lastname: Djella
authors.forename: C
authors.initials: C
authors.lastname: Yomgni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000904:Antibiotics, Antitubercular / Q000627:therapeutic use; D000995:Antitubercular Agents / Q000627:therapeutic use; D002163:Cameroon; D002648:Child; D016001:Confidence Intervals; D004977:Ethambutol / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007538:Isoniazid / Q000627:therapeutic use; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D016017:Odds Ratio; D011446:Prospective Studies; D011718:Pyrazinamide / Q000627:therapeutic use; D012293:Rifampin / Q000627:therapeutic use; D013183:Sputum / Q000382:microbiology*; D013997:Time Factors; D016896:Treatment Outcome; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy / Q000382:microbiology; D055815:Young Adult
chemical_list: D000904:Antibiotics, Antitubercular; D000995:Antitubercular Agents; D011718:Pyrazinamide; D004977:Ethambutol; D007538:Isoniazid; D012293:Rifampin