This study was planned to determine the prevalence of smear positive pulmonary TB among
patients receiving care at a tertiary reference Hospital - National Hospital
Abuja, Federal Capital Territory (FCT), Nigeria.
With an estimated 9.4 million new cases globally,
tuberculosis (TB) continues to be a major public health concern1.
Eighty percent of all cases worldwide occur in 22 high-burdens, mainly
resource-poor settings. This devastating impact of tuberculosis on vulnerable
populations is also driven by its deadly synergy with HIV. Therefore, building
capacity and enhancing universal access to rapid and accurate laboratory
diagnostics are necessary to control TB and HIV-TB co-infections in
resource-limited countries2. In low income countries (Nigeria
inclusive), Ziehl-Neelsen sputum smear microscopy is the only cost-effective
tool for diagnosis and monitoring of patients on treatment3.
There is dearth of data on the prevalence of pulmonary tuberculosis (PTB)
among patient attendees from individual Institutions and Health Care Facilities
performing sputum smear microscopy in Nigeria. This retrospective study will
analyze sputum smear microscopy results among pulmonary TB suspected patients
presenting to National Hospital Abuja, Federal Capital Territory (FCT),
Nigeria. 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 2010 to December 2014 were
retrieved from the TB Laboratory Register of the Medical Microbiology
department and analyzed.
hospital based retrospective study analyzed sputum smear microscopy results
among pulmonary TB suspected patients presenting to the National Hospital
Abuja, Federal Capital Territory, Nigeria. 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 2010 to
December 2013 were retrieved from the TB Laboratory Register of the Medical
Microbiology department and analyzed. Data processing and statistical analysis were performed using SPSS
software (Windows version 16.0). The results were expressed as percentage, with
significance at 5%.
overall prevalence of sputum smear positive cases were 17.3% (63 0f 364) and
most of the positive patients were within the age range 15 – 44 years. The
highest percentage of TB was seen in the age group of 15 - 24 years compared
with the lowest percentages in the age group below 14 years and above 45 years.
A total of 63 (17.3%) suspects were found to have at least one positive. Of
these, 56 (88.9% of those with one or more positive smears and 92% of those who
fulfilled the case definition) were detected from the first specimen and 7
(11.1%) were positive on the second specimen but not the first. The third
specimen did not have any additional diagnostic value for the detection of AFB.
Conclusion: The prevalence of sputum smear positive cases of
18.3% increases with age up to the age 44 years. Our result show that examining
two sputa smears was sufficient for the detection of AFB in our laboratory.
Further research involving different laboratories from all of the six geo-political
groups in Nigeria is needed to reassess these findings.
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