Factors predicting sputum smear conversion and treatment outcomes in new smear-positive pulmonary tuberculosis.
BACKGROUND
Epidemiological studies indicated that the proportion of TB patients who remained smear-positive after two months of treatment could be greater than 20%. The lack of smear conversion in the second month of treatment was one of the predictors of treatment failure and relapse.


OBJECTIVE
To determine factors associated with the persisting positive smear after two months of treatment and its value in predicting treatment failure.


METHODS
A 3-year retrospective cohort study was conducted in a 1,200-bed government hospital in Thailand New smear-positive tuberculosis patients who had pretreatment drug susceptibility test, the result of 2-month sputum smear and treatment outcomes were selected. The pretreatment drug susceptibility pattern and statistically differences on variables between groups of patients were described


RESULTS
Three hundred fifty six patients were included in the present study. The level of pretreatment isoniazid resistance and multi-drug resistance were 13.8% and 3.1% respectively. Factors associated with the 2-month positive smear were male sex, high initial sputum acid-fast bacilli grades, and cavitary diseases. The presence of human immuno-deficiency virus infection, drug resistance and the 2-month positive smear were significantly associated with treatment failure.


CONCLUSIONS
Male sex, high initial sputum acid-fast bacilli grades, and cavitary diseases were factors associated with the 2-month positive smear and increasing risk of treatment failure.
Department of Medicine, Rajavithi Hospital, College of Medicine, Rangsit University, Bangkok, Thailand. somkidou@yahoo.com
Somkid
S
Unsematham
Pairaj
P
Kateruttanakul
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000995:Antitubercular Agents / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D013183:Sputum / Q000382:microbiology*; D013785:Thailand; D017211:Treatment Failure; D018088:Tuberculosis, Multidrug-Resistant / Q000175:diagnosis* / Q000188:drug therapy; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy*; D055815:Young Adult
D000995:Antitubercular Agents