SUMMARY

Tuberculosis (TB) is a high burden global problem. Nigeria ranks fifth among the 22

high burden TB countries globally and first in Africa. Directly observed treatment short-

course (DOTS) is central to all TB control programs. One indicator of assessing the

effectiveness of DOTS is through sputum smear conversion rates at the end of intensive

phase. Whether some of the patients become smear negative early during the intensive

phase has not been investigated. There is lack of data to clarify this research question.

The rate and time to sputum smear conversion were determined as well as the

relationship between baseline sputum smear grades and time to sputum smear conversion

described.

A longitudinal study at National Tuberculosis and Leprosy Training Center, (NTBLTC)

Zaria was employed from January-June 2010. Data collection was by laboratory method

using Ziehl Neelsen staining technique for grading the bacillary load in the sputum at

diagnosis and weekly follow-up specimens. HIV status of each patient was determined

and 2007-2009 records analyzed. Data was entered and analyzed by Epi-Info version

3.5.1

Of the 62 patients analyzed, 67.7% were males with male/female ratio of 2:1. The

productive age group constituted 88.7% of those affected with median age of 32 years.

About 75.8% were HIV negative with TB/HIV co-infection of 24.2%; 79% were new TB

patients. Overall, Zaria and her immediate neighboring LGAs had 82.3% of patients.

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Of the 58 patients that converted, the mean time to sputum smear conversion was 2.7 ±

1.3 weeks, standard error (SE), 0.2 (95% confidence interval 2.3-3.1). Sputum smear

conversion rate peaked in week three with 71%. By the end of intensive phase,

conversion rate was 93.5%. At univariate analysis, by first week, 90% of sputum smear

grade of ≤ 1+ converted but none among sputum grade of 3+. Being HIV positive was

not associated with early conversion at bivariate analysis with p-value of 0.31 by Fisher’s

exact. Of the 611 records analyzed for 2007-2009, the average sputum conversion rate

was 82%. When conversion rate was categorized by sputum grade, it was statistically