Browsing by Author "Olweny, Francis"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Accuracy and Incremental Yield of the Chest X-Ray in Screening for Tuberculosis in Uganda: A Cross-Sectional Study
    (Tuberculosis research and treatment, 2021) Nalunjogi, Joanitah; Mugabe, Frank; Najjingo, Irene; Lusiba, Pastan; Olweny, Francis; Mubiru, Joseph; Kayongo, Edward; Sekibira, Rogers; Katamba, Achilles; Kirenga, Bruce
    TheWHOEND TB strategy requires ≥90% case detection to combat tuberculosis (TB). Increased TB case detection requires a more sensitive and specific screening tool. Currently, the symptoms recommended for screening TB have been found to be suboptimal since up to 44% of individuals with TB are asymptomatic. The chest X-ray (CXR) as a screening tool for pulmonary TB was evaluated in this study, as well as its incremental yield in TB diagnosis using a cross-sectional study involving secondary analysis of data of 4512 consented/assented participants ≥15 years who participated in the Uganda National TB prevalence survey between 2014 and 2015. Participants with a cough ≥2 weeks, fever, weight loss, and night sweats screened positive for TB using the symptoms screening method, while participants with a TB defining abnormality on CXR screened positive for TB by the CXR screening method. The Löwenstein-Jensen (LJ) culture was used as a gold standard for TB diagnosis. The CXR had 93% sensitivity and 65% specificity compared to LJ culture results, while symptoms had 76% sensitivity and 31% specificity. The screening algorithm involving the CXR in addition to symptoms led to a 38% increment in the yield of diagnosed tuberculosis. The number needed to screen using the CXR and symptoms screening algorithm was 32 compared to 45 when the symptoms are used alone. Therefore, the CXR in combination with symptoms is a good TB screening tool and increases the yield of diagnosed TB.
  • Thumbnail Image
    Item
    Accuracy of the chest x-ray in screening for tuberculosis in Uganda: A cross-sectional study.
    (Research Square, 2020) Nalunjogi, Joanitah; Mugabe, Frank; Najjingo, Irene; Lusiba, Pastan; Olweny, Francis; Mubiru, Joseph; Kayongo, Edward; Sekibira, Rogers; Katamba, Achilles; Kirenga, Bruce
    The WHO END TB strategy requires ≥90% case detection to combat tuberculosis (TB). Increased TB case detection requires a more sensitive and specific screening tool. Currently, the symptoms recommended for screening TB have been found to be sub-optimal. CXR as a screening tool for pulmonary TB was evaluated in this study, as well as factors related to its false positive results. METHODS: A cross sectional study of 4441 records of consented/assented participants ≥15 years. Participants with a cough ≥2 weeks and/or any abnormality in the lung on CXR were included in the study. Löwenstein-Jensen (LJ) culture was used as the gold standard. The CXR were categorised as Abnormal meaning presence of any CXR abnormality suggestive of active tuberculosis. Symptoms were categorised as abnormal meaning presence of any of cough ≥ 2 weeks, fever, weightloss or night sweats. RESULTS: The CXR had sensitivity 93%, specificity 65% compared to culture results while symptoms had sensitivity 76% and specificity 31%. The adjusted prevalence ratio (APR) of a false positive CXR result increased with age categories (years); 45 - 54, APR 1.18 (1.08, 1.29), 55 – 64 APR 1.18 (1.09, 1.29), 65+years APR 1.2 (1.10, 1.30).The APR was 0.93 (0.90, 0.96) among males and 0.86 (0.79, 0.93) among HIV positive individuals. CONCLUSIONS: The CXR is a fair tuberculosis screening tool and performed better than symptoms in Uganda.
  • Thumbnail Image
    Item
    Comparison of GeneXpert cycle threshold values with smear microscopy and culture as a measure of mycobacterial burden in five regional referral hospitals of Uganda- A cross-sectional study
    (PLoS ONE, 2019) Najjingo, Irene; Muttamba, Winters; Kirenga, Bruce J.; Nalunjogi, Joanitah; Bakesiima, Ritah; Olweny, Francis; Lusiba, Pastan; Katamba, Achilles; Joloba, Moses; Ssengooba, Willy
    Determining mycobacterial burden is important in assessing severity of disease, evaluating infectiousness and predicting patient treatment outcomes. Mycobacterial burden assessed by smear microscopy grade and time to culture positivity is clearly interpretable by most physicians. GeneXpert (Xpert) has been recommended by WHO as a first line tuberculosis (TB) diagnostic test as an alternative to smear microscopy. Xpert gives cycle threshold (Ct) values as a potential measure for mycobacterial burden. For physicians to clearly interpret Ct values as measures of mycobacterial burden, this study compared the Xpert quantification capabilities with those of smear microscopy and culture. The study also determined a linear relationship between Xpert Ct values and MGIT culture time to positivity (MGIT-TTP) and associated factors. A cut off Ct value which best predicts smear positivity was also determined using the Receiver Operator Curve analysis method. Results Excluding missing results and rifampicin resistant TB cases, a moderately strong correlation of 0.55 between Xpert Ct value and smear grade was obtained. A weak correlation of 0.37 was obtained between Xpert Ct values and MGIT time to positivity while that between Xpert Ct values and LJ culture was 0.34. The Xpert Ct values were found to increase by 2.57 for every unit increase in days to positive and HIV status was significantly associated with this relationship. A cut off Ct value of 23.62 was found to best predict smear positivity regardless of HIV status. Conclusion Our study findings show that GeneXpert Ct values are comparable to smear microscopy as a measure of M. tuberculosis burden and can be used to replace smear microscopy. However, given the low correlation between Xpert Ct value and culture positivity, Xpert Ct values cannot replace culture as a measure of M. tuberculosis burden among TB patients.
  • Thumbnail Image
    Item
    Dyslipidaemias in women using hormonal contraceptives: a cross sectional study in Mulago Hospital Family Planning Clinic, Kampala, Uganda
    (BMJ Open, 2018) Bakesiima, Ritah; Byakika-Kibwika, Pauline; Tumwine, James K.; Kalyango, Joan N.; Nabaasa, Gloria; Najjingo, Irene; Nabaggala, Grace S.; Olweny, Francis; Karamagi, Charles
    To determine the prevalence and factors associated with dyslipidaemias in women using hormonal contraceptives. Design Cross-sectional study Setting Mulago Hospital, Kampala, Uganda Participants Three hundred and eighty-four consenting women, aged 18–49 years, who had used hormonal contraceptives for at least 3 months prior to the study. Study outcome Dyslipidaemias (defined as derangements in lipid profile levels which included total cholesterol ≥200 mg/dL, high density lipoprotein <40 mg/ dL, triglyceride >150 mg/dL or low-density lipoprotein ≥160 mg/dL) for which the prevalence and associated factors were obtained.