Prevalence of smear positive tuberculosis among outpatient attendees, the case of the Tamale Teaching Hospital

Abstract

There is paucity of data on the prevalence of pulmonary tuberculosis (PTB) among out-patient attendees from individual Institutions and Health Care Facilities performing sputum smear microscopy in Ghana. This retrospective study analyzed sputum smear microscopy results among pulmonary TB suspected patients presenting to the Tamale Teaching Hospital in the Northern Region of Ghana. Sputum smear microscopy for Acid Fast Bacilli (AFB) results of new suspected pulmonary TB (Diagnosis) patients and their demographic data comprising age and sex recorded from January 2004 to December 2010 were retrieved from the TB Laboratory Register (TB04) of the Bacteriology unit and analyzed. Out of a total of 5,720 registered cases, 4,762 (83.3%) were new patients with suspected pulmonary TB (diagnostic cases). This comprised of 2,766 (58.1%) males and 1,996 (41.9%) females giving a female to male ratio of 1:1.4. Assessment of recorded data for newly suspected pulmonary TB patients rose from a minimum of 165 (9.9%) in 2004 to a maximum of 948(19.9%) in 2009. Out of a total of the 4,762 recorded new cases, 620 were sputum smear positive yielding positivity rate of 13.0%. The positivity rate on a year-on-year basis was 15.7% (2004), 15.8% (2005), 13.4% (2006), 12.7% (2007), 20.6% (2008), 10.0% (2009) and 6.3% (2010). The median age for recorded smear positive cases was 42 years. Generally the percentage proportion of smear positives in the recorded cases stratified by age showed a steady rise from 0.3% in the <5 year olds and peaked at 16.3% in the 30-35 years age group. A gradual decline in smear positive cases was ob-served within the 36 – 41 years age group from 10.0% to 4.8% in the 54 – 59 years age group from where a gradual rise was observed up to the >72 years age group. There has been a remarkable im-provement in diagnostic requests for suspected TB patients. The decline in positivity rates might have been impacted upon greatly by the national strategy to stop TB which emphasized on active case finding and prompt reporting at the community level, improving diagnostic processes and strengthening the health systems. The rapid urbanization and changes in the social fibre of inhab-itants cannot be underestimated in the overall TB control efforts.