NRU :: Browsing by Author "Joloba, Moses L."

Browsing by Author "Joloba, Moses L."

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Anti-Tuberculosis Drug Resistance among New and Previously Treated Sputum Smear-Positive Tuberculosis Patients in Uganda: Results of the First National Survey
(PloS one, 2013) Lukoye, Deus; Adatu, Francis; Musisi, Kenneth; Kasule, George William; Were, Willy; Odeke, Rosemary; Kalamya, Julius Namonyo; Joloba, Moses L.
Multidrug resistant and extensively drug resistant tuberculosis (TB) have become major threats to control of tuberculosis globally. The rates of anti-TB drug resistance in Uganda are not known. We conducted a national drug resistance survey to investigate the levels and patterns of resistance to first and second line anti-TB drugs among new and previously treated sputum smear-positive TB cases.
Assessing a transmission network of Mycobacterium tuberculosis in an African city using single nucleotide polymorphism threshold analysis
(MicrobiologyOpen, 2021) Yassine, Edriss; Galiwango, Ronald; Ssengooba, Willy; Ashaba, Fred; Joloba, Moses L.; Zalwango, Sarah; Whalen, Christopher C.; Quinn, Frederick
Tuberculosis (TB) is the leading cause of death in humans by a single infectious agent worldwide with approximately two billion humans latently infected with the bacterium Mycobacterium tuberculosis. Currently, the accepted method for controlling the disease is Tuberculosis Directly Observed Treatment Shortcourse (TB-DOTS). This program is not preventative and individuals may transmit disease before diagnosis, thus better understanding of disease transmission is essential. Using whole-genome sequencing and single nucleotide polymorphism analysis, we analyzed genomes of 145 M. tuberculosis clinical isolates from active TB cases from the Rubaga Division of Kampala, Uganda. We established that these isolates grouped into M. tuberculosis complex (MTBC) lineages 1, 2, 3, and 4, with the most isolates grouping into lineage 4. Possible transmission pairs containing ≤12 SNPs were identified in lineages 1, 3, and 4 with the prevailing transmission in lineages 3 and 4. Furthermore, investigating DNA codon changes as a result of specific SNPs in prominent virulence genes including plcA and plcB could indicate potentially important modifications in protein function. Incorporating this analysis with corresponding epidemiological data may provide a blueprint for the integration of public health interventions to decrease TB transmission in a region.
Association between serotonin transporter gene polymorphisms and increased suicidal risk among HIV positive patients in Uganda
(BMC genetics, 2017) Kalungi, Allan; Seedat, Soraya; Hemmings, Sian M. J.; Merwe, Lize van der; Joloba, Moses L.; Nanteza, Ann; Nakassujja, Noeline; Birabwa, Harriet; Serwanga, Jennifer; Kaleebu, Pontiano; Kinyanda, Eugene
Persons living with HIV/AIDS (PLWHA) are at an increased risk of suicide. Increased suicidal risk is a predictor of future attempted and completed suicides and has been associated with poor quality of life and poor adherence with antiretroviral therapy. Clinical risk factors have low predictive value for suicide, hence the interest in potential neurobiological correlates and specific heritable markers of suicide vulnerability. The serotonin transporter gene has previously been implicated in the aetiology of increased suicidal risk in non-HIV infected study populations and its variations may provide a platform for identifying genetic risk for suicidality among PLWHA. The present cross-sectional study aimed at identifying two common genetic variants of the serotonin transporter gene and their association with increased suicidal risk among human immunodeficiency virus (HIV)-positive adults in Uganda. Results: The prevalence of increased suicidal risk (defined as moderate to high risk suicidality on the suicidality module of the Mini Neuropsychiatric Interview (M.I.N.I) was 3.3% (95% CI, 2.0–5.3). The 5-HTTLPR was found to be associated with increased suicidal risk before Bonferroni correction (p-value = 0.0174). A protective effect on increased suicidal risk was found for the 5-HTTLPR/rs25531 SA allele (p-value = 0.0046)- which directs reduced expression of the serotonin transporter gene (5-HTT). Conclusion: The SA allele at the 5-HTTLPR/rs25531 locus is associated with increased suicidal risk among Ugandan PLWHA. Further studies are needed to validate this finding in Ugandan and other sub-Saharan samples.
Association of circulating serum free bioavailable and total vitamin D with cathelicidin levels among active TB patients and household contacts
(Research Square, 2022) Acen, Ester Lilian; Worodria, William; Kateete, David Patrick; Olum, Ronald; Joloba, Moses L.; Akintola, Ashraf; Bbuye, Mudarshiru; Biraro Andia, Irene
The free hormone hypothesis postulates that the estimation of free circulating 25(OH)D may be a better marker of vitamin D status and is of clinical importance compared to total vitamin D levels because it is the fraction involved in biological activities. Studies have shown that cathelicidin inhibits the growth of Mycobacterium Tuberculosis in a vitamin D-dependent manner and therefore adequate vitamin D is required for its expression. The aim of the study was to determine the association between serum-free and bioavailable and total vitamin D with LL-37 levels in ATB patients, LTBI and individuals with no TB infection. This was a cross sectional study and free and bioavailable vitamin D and LL-37 levels were measured. 95 specimens were further selected to estimate total vitamin D levels. The median free and bioavailable vitamin D levels of study participants were 3.8 ng/mL. The median LL-37 levels were 318.8 ng/mL. The mean total vitamin D levels were 18.9 ng/mL. Significantly weak inverse associations were found and vitamin D is involved in the regulation of LL-37 expression and low vitamin D levels can alter this relationship. Background Vitamin D deficiency is a prominent risk factor for TB disease worldwide (1–5). Vitamin D can be obtained in two forms, D2 is obtained through diet and D3 is obtained through skin biosynthesis (6). Its main circulating active metabolite 1, 25(OH)D is involved in regulation of antimicrobial activity and therefore important in TB therapy (7). So far, total vitamin D or 25(OH)D has been considered a better index for determining vitamin D status due to its longer half-life (6, 8–11). However, the free hormone hypothesis postulates that the estimation of free circulating 25(OH)D may be a better marker of vitamin D status and is of clinical importance compared to total vitamin D levels because it is the fraction involved in biological activities (10, 12–14). Bioavailable 25(OH)D is used to represent free vitamin D and the 10–15% fraction is loosely bound to albumin (8, 15). About 85–90% of total 25(OH)D is bound to VDBP and 10–15% is loosely bound to albumin and a small fraction remains unbound (13, 16). Free 25(OH)D is increased and readily available to cells when DBP levels are at low concentrations Previous studies report that changes in DBP levels and 25(OH)D binding affinity can lead to higher levels of free 25(OH)D, even in the absence of total vitamin D levels (17, 18). According to the Endocrine Society, total vitamin D status is classified into three groups: <20 ng/mL deficient, 21–29 ng/mL deficient, and > 30 ng/mL optimal; or sufficient amounts (19). In vitro and in vivo studies have shown that LL-37 inhibits the growth of MTB in a vitamin D-dependent manner (20, 21). Accordingly, studies have reported that adequate levels of 25(OH)D are required for expression of LL-37(22, 23). According to our systematic review, six studies reported that vitamin D regulates LL-37 expression and that vitamin D deficiency alters this function (24). Because the free fraction of vitamin D, which enters cells to cause biological effects, has not been studied with the LL-37 molecule, we hypothesize that there is no relationship between free and bioavailable vitamin D and total vitamin D with the LL-37 levels among the ATB patients, LTBI and individuals with no TB infection. This study aimed to determine the association between serum-free and bioavailable and total vitamin D with LL-37 levels in ATB patients, LTBI and individuals with no TB infection.
Biobanking: Strengthening Uganda’s Rapid Response to COVID-19 and Other Epidemics
(Biopreservation and Biobanking, 2021) Kamulegeya, Rogers; Kateete, David Patrick; Bagaya, Bernard S.; Nasinghe, Emmanuel; Muttamba, Winters; Nsubuga, Gideon; Kigozi, Edgar; Ashaba Katabazi, Fred; Nakwagala, Fred; Kalungi, Sam; Byamugisha, Josaphat; Worodria, William; Magala, Rose; Kirenga, Bruce; Joloba, Moses L.
SARS-CoV-2 is a fatal disease of global public health concern. Measures to reduce its spread critically depend on timely and accurate diagnosis of virus-infected individuals. Biobanks can have a pivotal role in elucidating disease etiology, translation, and advancing public health. In this article, we show how a biobank has been a critical resource in the rapid response to coronavirus disease of 2019 (COVID-19) in Uganda. Materials and Methods: The Integrated Biorepository of H3Africa Uganda established a COVID-19 biobank. Standard Operating Procedures for sample and data collection, sample processing, and storage were developed. An e-questionnaire data tool was used to collect sociodemographic factors. Samples were collected at 7-day intervals from patients, analyzed for key parameters, processed, annotated, characterized, and stored at appropriate temperatures. Results: Stored samples have been used in validation of 17 diagnostic kits, the Cepheid Xpert Xpress SARSCoV- 2 assay, as well as a sample pooling technique for mass screening and polymerase chain reaction assay validation. Kits that passed validation were deployed for mass screening boosting early detection, isolation, and treatment of COVID-19 cases. Also, 10 applications from researchers and biotech companies have been received and approved and 4 grants have been awarded Conclusion: The CoV-Bank has proven to be an invaluable resource in the fight against the COVID-19 pandemic in Uganda, as samples have been resources in the validation and development of COVID-19 diagnostic tools, which are important in tracing and isolation of infected cases to confront, delay, and stop the spread of the SARS-CoV-2 virus.
Comparison of MGIT and Myco/F Lytic Liquid-Based Blood Culture Systems for Recovery of Mycobacterium tuberculosis from Pleural Fluid
(Journal of clinical microbiology, 2015) Harausz, Elizabeth; Kafuluma Lusiba, John; Nsereko, Mary; Johnson, John L.; Toossi, Zahra; Ogwang, Sam; Boom, Henry; Joloba, Moses L.
Tuberculosis (TB) is the most frequent cause of exudative pleural effusions in areas of high TB incidence. Studies have shown that Mycobacterium tuberculosis is the causative agent in up to 44% of HIV-seronegative people hospitalized with a pleural effusion (1–3), and the percentage is higher in HIV-seropositive people (4). Pleural TB is a paucibacillary disease. The pathogenesis of a tuberculous pleural effusion is likely due to a delayed hypersensitivity reaction to M. tuberculosis proteins (for a review, see reference 5) and not to a large burden of organisms. The scarcity of organisms makes it difficult to isolate M. tuberculosis from pleural fluid samples, leading to low rates of culture confirmation. Rich culture media are generally more sensitive in detecting M. tuberculosis in sputum and other clinical samples (6). Few studies have compared different liquid media and examined their potential role in combination with solid media for the diagnosis of tuberculous pleurisy. In this study, we compared the Bactec 9120 Myco/F lytic blood culture system (Myco/F lytic) to the Bactec mycobacterial growth indicator tube (MGIT) 960 system (Becton Dickinson, Sparks, MD) (with each liquid system used in conjunction with locally prepared Middlebrook 7H11 solid medium) with respect to time to positivity (TTP), sensitivity, specificity, and percent culture yield of M. tuberculosis isolates from pleural fluid.
Comparison of transformation frequencies among selected Streptococcus pneumoniae serotypes
(International journal of antimicrobial agents, 2010) Joloba, Moses L.; Kidenya, Benson R.; Kateete, David P.; Katabazi, Fred A.; Muwanguzi, Julian K.; Asiimwe, Benon B.; Alarakol, Simon P.; Nakavuma, Jessica L.; Bajaksouzian, Saralee; Windau, Anne; Jacobs, Michael R.
Although there are over 90 serotypes of Streptococcus pneumoniae, antimicrobial resistance is predominantly found in a limited number of serotypes/serogroups, namely 6, 9, 14, 19 and 23. There is no compelling mechanism to account for this restriction. We aimed to determine whether serotypes commonly associated with drug resistance have higher transformation frequencies than those that are susceptible to antimicrobial agents. An in vitro investigation of the genetic transformation frequency of drug-resistant serotypes compared with that of susceptible serotypes under the influence of synthetic competence-stimulating peptides was performed. The transforming DNA was genomic DNA carrying a Tn916-like transposon containing the mefE gene that confers resistance to erythromycin. It was observed that serotypes 6, 9, 14, 19 and 23, which are highly associated with drug resistance, do not exhibit a higher degree of transformation efficiency than other serotypes. These findings suggest that the association of serotype with drug resistance is likely due to prolonged exposure to transforming DNA resulting from longer nasopharyngeal carriage and to a greater selective pressure from antimicrobials, particularly in children. This is the first study to compare the transformation frequencies of pneumococcal clinical isolates using genomic DNA that carries the composite Tn916-like element.
Discordance of the Repeat GeneXpert MTB/RIF Test for Rifampicin Resistance Detection Among Patients Initiating MDR-TB Treatment in Uganda
(In Open forum infectious diseases, 2021) Ssengooba, Willy; Iragena, Jean de Dieu; Komakech, Kevin; Okello, Iginitius; Nalunjogi, Joanitah; Katagira, Winceslaus; Kimuli, Ivan; Adakun, Susan; Joloba, Moses L.; Torrea, Gabriela; Kirenga, Bruce J.
The Global Laboratory Initiative (GLI) guidelines recommend repeat for GeneXpertMTB/RIF (XpertMTB/RIF) in patients with a low pretest probability of rifampicin resistance (RR). This was a cross-sectional study using results of sputum specimens collected from participants screened for the STREAM 2 trial. We recruited all patients with XpertMTB/RIF RR-TB detected who were referred for RR/multidrug-resistant (MDR) TB treatment initiation at Mulago National Referral Hospital, Kampala, between September 2017 and October 2019. At baseline, smear microscopy, repeat XpertMTB/RIF, Xpert Ultra, and MTBDRplus assays were done on sputum specimens. Culturebased drug susceptibility testing (DST) was performed on discordant specimens. We analyzed the prevalence and factors associated with discordance between initial and repeat XpertMTB/RIF RR and false XpertMTB/RIF RR. False XpertMTB/RIF RR was defined as no RR detected by any of Xpert Ultra, LPA, or culture DST (reference comparator).
Distribution and transmission of Mycobacterium tuberculosis complex lineages among children in peri-urban Kampala, Uganda
(BMC pediatrics, 2015) Wampande, Eddie M.; Mupere, Ezekiel; Jaganath, Devan; Nsereko, Mary; Mayanja, Harriet K.; Eisenach, Kathleen; Boom, W. Henry; Gagneu, Sebastien; Joloba, Moses L.
To gain insight into the transmission of tuberculosis (TB) in peri-urban Kampala-Uganda, we performed a household contact study using children as a surrogate for recent transmission of Mycobacterium tuberculosis (MTB). Using this approach, we sought to understand M. tuberculosis complex (MTBC) lineage diversity, distribution and how these relate to TB transmission to exposed children. Method: MTBC isolates from children aged ≤ 15 years, collected from 2002 to 2010 in a household-contact study, were analyzed using a LightCycler RT-PCR SNP genotyping assay (LRPS). The resultant genotypic data was used to determine associations between MTBC lineage and the children’s clinical and epidemiological characteristics. Results and discussion: Of the 761 children surveyed, 9 % (69/761) had culture-positive TB an estimate in the range of global childhood TB; of these 71 % (49/69) were infected with an MTBC strain of the “Uganda family”, 17 % (12/69) infected with MTBC lineage 4 strains other than MTBC Uganda family and 12 % (8/69) infected with MTBC lineage 3, thereby disproportionately causing TB in the study area. Overall the data showed no correlation between the MTBC lineages studied and transmission (OR = 0.304; P-value = 0.251; CI: 95 %; 0.039-2.326) using children a proxy for TB transmission. Conclusions: Our findings indicate that MTBC Uganda family strains are the main cause of TB in children in peri-urban Kampala. Furthermore, MTBC lineages did not differ in their transmissibility to children.
Effectiveness of the standard WHO recommended retreatment regimen (Category II) for tuberculosis in Kampala, Uganda
(PLoS medicine, 2011) Jones-López, Edward C.; Ayakaka, Irene; Levin, Jonathan; Reilly, Nancy; Mumbowa, Francis; Dryden-Peterson, Scott; Nyakoojo, Grace; Fennelly, Kevin; Temple, Beth; Nakubulwa, Susan; Joloba, Moses L.; Okwera, Alphonse; Eisenach, Kathleen D.; McNerney, Ruth; Elliott, Alison M.; Ellner, Jerrold J.; Smith, Peter G.; Mugerwa, Roy D.
Each year, 10%–20% of patients with tuberculosis (TB) in low- and middle-income countries present with previously treated TB and are empirically started on a World Health Organization (WHO)-recommended standardized retreatment regimen. The effectiveness of this retreatment regimen has not been systematically evaluated. Methods and Findings: From July 2003 to January 2007, we enrolled smear-positive, pulmonary TB patients into a prospective cohort to study treatment outcomes and mortality during and after treatment with the standardized retreatment regimen. Median time of follow-up was 21 months (interquartile range 12–33 months). A total of 29/148 (20%) HIV-uninfected and 37/140 (26%) HIV-infected patients had an unsuccessful treatment outcome. In a multiple logistic regression analysis to adjust for confounding, factors associated with an unsuccessful treatment outcome were poor adherence (adjusted odds ratio [aOR] associated with missing half or more of scheduled doses 2.39; 95% confidence interval (CI) 1.10–5.22), HIV infection (2.16; 1.01–4.61), age (aOR for 10-year increase 1.59; 1.13–2.25), and duration of TB symptoms (aOR for 1-month increase 1.12; 1.04–1.20). All patients with multidrug-resistant TB had an unsuccessful treatment outcome. HIV-infected individuals were more likely to die than HIV-uninfected individuals (p,0.0001). Multidrug-resistant TB at enrolment was the only common risk factor for death during follow-up for both HIV-infected (adjusted hazard ratio [aHR] 17.9; 6.0–53.4) and HIV-uninfected (14.7; 4.1–52.2) individuals. Other risk factors for death during follow-up among HIVinfected patients were CD4,50 cells/ml and no antiretroviral treatment (aHR 7.4, compared to patients with CD4$200; 3.0– 18.8) and Karnofsky score ,70 (2.1; 1.1–4.1); and among HIV-uninfected patients were poor adherence (missing half or more of doses) (3.5; 1.1–10.6) and duration of TB symptoms (aHR for a 1-month increase 1.9; 1.0–3.5). Conclusions: The recommended regimen for retreatment TB in Uganda yields an unacceptable proportion of unsuccessful outcomes. There is a need to evaluate new treatment strategies in these patients.
Endothelial Activation, Acute Kidney Injury, and Cognitive Impairment in Pediatric Severe Malaria
(Critical care medicine, 2020) Ouma, Benson J.; Ssenkusu, John M.; Shabani, Estela; Datta, Dibyadyuti; Opoka, Robert O.; Idro, Richard; Bangirana, Paul; Park, Gregory; Joloba, Moses L.; Kain, Kevin C.; John, Chandy C.; Conroy, Andrea L.
Evaluate the relationship between endothelial activation, malaria complications, and long-term cognitive outcomes in severe malaria survivors.Prospectively cohort study of children with cerebral malaria, severe malarial anemia, or community children. Mulago National Referral Hospital in Kampala, Uganda.Children 18 months to 12 years old with severe malaria (cerebral malaria, n = 253 or severe malarial anemia, n = 211) or community children (n = 206) were followed for 24 months.Children underwent neurocognitive evaluation at enrollment (community children) or a week following hospital discharge (severe malaria) and 6, 12, and 24 months follow-up. Endothelial activation was assessed at admission on plasma samples (von Willebrand factor, angiopoietin-1 and angiopoietin-2, soluble intercellular adhesion molecule-1, soluble vascular cell adhesion molecule-1, soluble E-Selectin, and P-Selectin). False discovery rate was used to adjust for multiple comparisons. Severe malaria was associated with widespread endothelial activation compared with community children (p < 0.0001 for all markers). Acute kidney injury was independently associated with changes in von Willebrand factor, soluble intercellular adhesion molecule-1, soluble E-Selectin, P-Selectin, and angiopoietin-2 (p < 0.0001 for all). A log10 increase in angiopoietin-2 was associated with lower cognitive z scores across age groups (children < 5, β −0.42, 95% CI, −0.69 to −0.15, p = 0.002; children ≥ 5, β −0.39, 95% CI, −0.67 to −0.11, p = 0.007) independent of disease severity (coma, number of seizures, acute kidney injury) and sociodemographic factors. Angiopoietin-2 was associated with hemolysis (lactate dehydrogenase, total bilirubin) and inflammation (tumor necrosis factor-α, interleukin-10). In children with cerebral malaria who had a lumbar puncture performed, angiopoietin-2 was associated with blood-brain barrier dysfunction, and markers of neuroinflammation and injury in the cerebrospinal fluid (tumor necrosis factor-α, kynurenic acid, tau).These data support angiopoietin-2 as a measure of disease severity and a risk factor for long-term cognitive injury in children with severe malaria.
Evaluation of Cepheid’s Xpert MTB/RIF Test on Pleural Fluid in the Diagnosis of Pleural Tuberculosis in a High Prevalence HIV/TB Setting
(PLoS ONE, 2014) Lusiba, John K.; Nakiyingi, Lydia; Kirenga, Bruce J.; Kiragga, Agnes; Lukande, Robert; Nsereko, Maria; Ssengooba, Willy; Katamba, Achilles; Worodria, William; Joloba, Moses L.; Mayanja-Kizza, Harriet
Diagnosis of pleural tuberculosis (TB) using routinely available diagnostic methods is challenging due to the paucibacillary nature of the disease. Histopathology and pleural tissue TB culture involves an invasive procedure which requires expertise and appropriate equipment, both often unavailable in many health units. Xpert MTB/Rif test has been widely evaluated in sputum specimens but data on its performance in pleural TB is scarce. We evaluated the accuracy of Cepheid’s Xpert MTB/Rif test on pleural fluid in the diagnosis of pleural TB in Uganda. Methods: Consenting adult patients with exudative pleural effusions underwent pleural biopsy and the tissue obtained subjected to Lowenstein-Jensen and mycobacterial growth indicator tube MTB cultures and histopathology. Pleural fluid for Xpert MTB/Rif testing was also collected. Data on socio-demographic characteristics, clinical symptoms, HIV status and CD4 count were also collected. Sensitivity, specificity, positive and negative predictive values of Xpert MTB/Rif test on pleural fluid in pleural TB diagnosis were calculated using pleural tissue MTB culture and/or histopathology as the reference standard. Results: Of the 116 participants [female 50%, mean age 34 (SD 613], 87/116 (75%) had pleural TB confirmed on pleural tissue culture and/or histopathology. The Xpert MTB/Rif test identified 25 (28.7%) of the 87 confirmed pleural TB cases. The sensitivity and specificity of Xpert MTB/Rif test were 28.7% and 96.6% respectively while the positive and negative predictive values were 96.1% and 31.1% respectively. Conclusion: Xpert MTB/Rif test on pleural fluid does not accurately diagnose pleural TB and therefore cannot be used as an initial evaluation test in patients with suspected pleural TB. New, rapid and accurate tests for the diagnosis of pleural TB are still warranted.
Evaluation of circulating serum cathelicidin levels as a potential biomarker to discriminate between active and latent tuberculosis in Uganda
(PloS one, 2022) Acen, Ester Lilian; Kateete, David Patrick; Worodria, William; Olum, Ronald; Joloba, Moses L.; Bbuye, Mudarshiru; Biraro, Irene Andia
Tuberculosis remains a major public health problem worldwide accounting for 1.4 million deaths annually. LL-37 is an effector molecule involved in immunity with both antimicrobial and immunomodulatory properties. The purpose of this study was to compare LL-37 circulatory levels among participants with active and latent tuberculosis and to determine its ability to discriminate between the two infectious states. Methods A cross-sectional study was performed among 56 active tuberculosis patients, 49 latent tuberculosis individuals, and 43 individuals without tuberculosis infection. The enzymelinked immunosorbent assay was used to assess LL-37 levels. Data analysis was performed using STATA software and Graph pad Prism version 8. Mann-Whitney U test was used for correlation between variables with two categories and the Kruskal-Wallis test for three or more categories. Results The study had more female participants than males, with similar median ages across the three groups, 29.5, 25.0, and 23.0 years respectively. Active tuberculosis patients had significantly higher LL-37 levels compared to those with latent tuberculosis and without tuberculosis. The median/interquartile ranges were 318.8 ng/ml (157.9–547.1), 242.2 ng/ml (136.2–579.3), 170.9 ng/ml (129.3–228.3); p = 0.002 respectively. Higher LL-37 was found in the male participant with median/interquartile range, 424.8 ng/ml (226.2–666.8) compared to the females 237.7 ng/ml (129.6–466.6); p = 0.045. LL-37 had better discriminatory potential between active tuberculosis and no tuberculosis (AUC = 0.71, sensitivity 71.4% specificity = 69.8%) than with latent tuberculosis (AUC = 0.55, sensitivity = 71.4%, specificity = 44.9%). There was moderate differentiation between latent tuberculosis and no tuberculosis (AUC = 0.63, sensitivity = 44.9% specificity = 90.7%). Conclusion Significantly higher LL-37 levels were observed among active tuberculosis patients than those without tuberculosis infection and were, therefore able to discriminate between active tuberculosis and other tuberculosis infectious states, especially with no tuberculosis. Further assessment of this biomarker as a screening tool to exclude tuberculosis is required.
Evaluation of in-house PCR for diagnosis of smear-negative pulmonary tuberculosis in Kampala, Uganda
(BMC Research Notes, 2012) Nakiyingi, Lydia; Kateete, David P.; Ocama, Ponsiano; Worodria, William; Sempa, Joseph B.; Asiimwe, Benon B.; Katabazi, Fred A.; Katamba, Achilles; Huang, Laurence; Joloba, Moses L.; Mayanja-Kizza, Harriet
Nucleic acid amplification tests (NAATs) have offered hope for rapid diagnosis of tuberculosis (TB). However, their efficiency with smear-negative samples has not been widely studied in low income settings. Here, we evaluated in-house PCR assay for diagnosis of smear-negative TB using Lowenstein-Jensen (LJ) culture as the baseline test. Two hundred and five pulmonary TB (PTB) suspects with smear-negative sputum samples, admitted on a short stay emergency ward at Mulago Hospital in Kampala, Uganda, were enrolled. Two smear-negative sputum samples were obtained from each PTB suspect and processed simultaneously for identification of MTBC using in-house PCR and LJ culture. Results: Seventy two PTB suspects (35%, 72/205) were LJ culture positive while 128 (62.4%, 128/205) were PCR-positive. The sensitivity and specificity of in-house PCR for diagnosis of smear-negative PTB were 75% (95% CI 62.6-85.0) and 35.9% (95% CI 27.2-45.3), respectively. The positive and negative predictive values were 39% (95% CI 30.4-48.2) and 72.4% (95% CI 59.1-83.3), respectively, while the positive and negative likelihood ratios were 1.17 (95% CI 0.96-1.42) and 0.70 (95% CI 0.43-1.14), respectively. One hundred and seventeen LJ culturenegative suspects (75 PCR-positive and 42 PCR-negative) were enrolled for follow-up at 2 months. Of the PCR-positive suspects, 45 (60%, 45/75) were still alive, of whom 29 (64.4%, 29/45) returned for the follow-up visit; 15 (20%, 15/75) suspects died while another 15 (20%, 15/75) were lost to follow-up. Of the 42 PCR-negative suspects, 22 (52.4%, 22/42) were still alive, of whom 16 (72.7%, 16/22) returned for follow-up; 11 (26.2%, 11/42) died while nine (21.4%, 9/42) were lost to follow-up. Overall, more PCR-positive suspects were diagnosed with PTB during follow-up visits but the difference was not statistically significant (27.6%, 8/29 vs. 25%, 4/16, p = 0.9239). Furthermore, mortality was higher for the PCR-negative suspects but the difference was also not statistically significant (26.2% vs. 20% p = 0.7094). Conclusion: In-house PCR correlates poorly with LJ culture for diagnosis of smear-negative PTB. Therefore, in-house PCR may not be adopted as an alternative to LJ culture.
Evaluation Of The Xpert MTB/RIF Test For The Diagnosis Of Childhood Pulmonary Tuberculosis In Uganda: A Cross-Sectional Diagnostic Study
(BMC infectious diseases, 2013) Sekadde, Moorine Penninah; Wobudeya, Eric; Joloba, Moses L.; Ssengooba, Willy; Kisembo, Harriet; Kitaka, Sabrina Bakeera; Musoke, Philippa
The diagnosis of childhood tuberculosis remains a challenge worldwide. The Xpert MTB/RIF test, a rapid mycobacteria tuberculosis diagnostic tool, was recommended for use in children based on data from adult studies. We evaluated the performance of the Xpert MTB/RIF test for the diagnosis of childhood pulmonary tuberculosis using one induced sputum sample and described clinical characteristics associated with a positive Xpert MTB/RIF test. The sputum culture on both Lowenstein-Jensen (LJ) and Mycobacteria Growth Indicator Tube (MGIT) was the gold standard.We consecutively enrolled 250 Ugandan children aged 2 months to 12 years with suspected pulmonary tuberculosis between January 2011 and January 2012 into a cross-sectional diagnostic study at a tertiary care facility in Uganda.We excluded data from 15 children (13 contaminated culture and 2 indeterminate MTB/RIF test results) and analysed 235 records. The Xpert MTB/RIF test had a sensitivity of 79.4% (95% CI 63.2 - 89.7) and a specificity of 96.5% (95% CI 93 – 98.3). The Xpert MTB/RIF test identified 13 of the 14 (92.9%) smear positive-culture positive and 14 of the 20 (70%) smear negative -culture positive cases. The Xpert MTB/RIF identified twice as many cases as the smear microscopy (79.4% Vs 41.2%). Age > 5 years (OR 3.3, 95% CI 1.4 – 7.4, p value 0.005), a history of Tuberculosis (TB) contact (OR 2.4, 95% CI 1.1 – 5.2, p value 0.03), and a positive tuberculin skin test (OR 4.1, 95% CI 1.7 – 10, p value 0.02) was associated with a positive Xpert MTB/RIF test. The median time to TB detection was 49.5 days (IQR 38.4-61.2) for LJ, and 6 days (IQR 5 – 11.5) for MGIT culture and 2 hours for the Xpert MTB/RIF test.The Xpert MTB/RIF test on one sputum sample rapidly and correctly identified the majority of children with culture confirmed pulmonary tuberculosis with high specificity.
Evaluation of the Xpert MTB/RIF test for the diagnosis of childhood pulmonary tuberculosis in Uganda: a cross-sectional diagnostic study
(BioMed Central, 2013) Sekadde, Moorine Penninah; Wobudeya, Eric; Joloba, Moses L.; Ssengooba, Willy; Kisembo, Harriet; Musoke, Philippa; Bakeera-kitaka, Sabrina
Background: The diagnosis of childhood tuberculosis remains a challenge worldwide. The Xpert MTB/RIF test, a rapid mycobacteria tuberculosis diagnostic tool, was recommended for use in children based on data from adult studies. We evaluated the performance of the Xpert MTB/RIF test for the diagnosis of childhood pulmonary tuberculosis using one induced sputum sample and described clinical characteristics associated with a positive Xpert MTB/RIF test. The sputum culture on both Lowenstein-Jensen (LJ) and Mycobacteria Growth Indicator Tube (MGIT) was the gold standard. Methods: We consecutively enrolled 250 Ugandan children aged 2 months to 12 years with suspected pulmonary tuberculosis between January 2011 and January 2012 into a cross-sectional diagnostic study at a tertiary care facility in Uganda. Results: We excluded data from 15 children (13 contaminated culture and 2 indeterminate MTB/RIF test results) and analysed 235 records. The Xpert MTB/RIF test had a sensitivity of 79.4% (95% CI 63.2 - 89.7) and a specificity of 96.5% (95% CI 93 – 98.3). The Xpert MTB/RIF test identified 13 of the 14 (92.9%) smear positive-culture positive and 14 of the 20 (70%) smear negative -culture positive cases. The Xpert MTB/RIF identified twice as many cases as the smear microscopy (79.4% Vs 41.2%). Age>5 years (OR 3.3, 95% CI 1.4 – 7.4, p value 0.005), a history of Tuberculosis (TB) contact (OR 2.4, 95% CI 1.1 – 5.2, p value 0.03), and a positive tuberculin skin test (OR 4.1, 95% CI 1.7 – 10, p value 0.02) was associated with a positive Xpert MTB/RIF test. The median time to TB detection was 49.5 days (IQR 38.4-61.2) for LJ, and 6 days (IQR 5 – 11.5) for MGIT culture and 2 hours for the Xpert MTB/RIF test.
Frequency and patterns of second-line resistance conferring mutations among MDR-TB isolates resistant to a second-line drug from eSwatini, Somalia and Uganda (2014–2016)
(BMC pulmonary medicine, 2019) Kateete, David Patrick; Kamulegeya, Rogers; Kigozi, Edgar; Katabazi, Fred Ashaba; Lukoye, Deus; Sebit, Sindani Ireneaus; Abdi, Hergeye; Arube, Peter; Kasule, George William; Musisi, Kenneth; Dlamini, Myalo Glen; Khumalo, Derrick; Joloba, Moses L.
Pulmonary tuberculosis is a leading cause of morbidity and mortality in developing countries. Drug resistance, a huge problem in this contagious disease, is driven by point mutations in the Mycobacterium tuberculosis genome however, their frequencies vary geographically and this affects applicability of molecular diagnostics for rapid detection of resistance. Here, we report the frequency and patterns of mutations associated with resistance to second-line anti-TB drugs in multidrug-resistant (MDR) M. tuberculosis isolates from eSwatini, Somalia and Uganda that were resistant to a second-line anti-TB drug.The quinolone resistance determining region (QRDR) of gyrA/gyrB genes and the drug resistance associated fragment of rrs gene from 80 isolates were sequenced and investigated for presence of drug resistance mutations. Of the 80 isolates, 40 were MDR, of which 28 (70%) were resistant to a second-line anti-TB injectable drug, 18 (45%) were levofloxacin resistant while 12 (30%) were extensively drug resistant (XDR). The remaining 40 isolates were susceptible to anti-TB drugs. MIRU-VNTR analysis was performed for M/XDR isolates.We successfully sub-cultured 38 of the 40 M/XDR isolates. The gyrA resistance mutations (Gly88Ala/Cys/Ala, Ala90Val, Ser91Pro, Asp94Gly/Asn) and gyrB resistance mutations (Asp500His, Asn538Asp) were detected in 72.2% (13/18) and 22.2% (4/18) of the MDR and levofloxacin resistant isolates, respectively. Overall, drug resistance mutations in gyrA/gyrB QRDRs occurred in 77.8% (14/18) of the MDR and levofloxacin resistant isolates. Furthermore, drug resistance mutations a1401g and g1484 t in rrs occurred in 64.3% (18/28) of the MDR isolates resistant to a second-line anti-TB injectable drug. Drug resistance mutations were not detected in drug susceptible isolates.The frequency of resistance mutations to second-line anti-TB drugs in MDR-TB isolates resistant to second line anti-TB drugs from eSwatini, Somalia and Uganda is high, implying that rapid molecular tests are useful in detecting second-line anti-TB drug resistance in those countries. Relatedly, the frequency of fluoroquinolone resistance mutations in gyrB/QRDR is high relative to global estimates, and they occurred independently of gyrA/QRDR mutations implying that their absence in panels of molecular tests for detecting fluoroquinolone resistance may yield false negative results in our setting.
Identification of Staphylococcus aureus: DNase and Mannitol salt agar improve the efficiency of the tube coagulase test
(Annals of clinical microbiology and antimicrobials, 2010) Kateete, David P.; Kimani, Cyrus N.; Katabazi, Fred A.; Okeng, Alfred; Okee, Moses S.; Nanteza, Ann; Joloba, Moses L.; Najjuka, Florence C.
The ideal identification of Staphylococcus aureus clinical isolates requires a battery of tests and this is costly in resource limited settings. In many developing countries, the tube coagulase test is usually confirmatory for S. aureus and is routinely done using either human or sheep plasma. This study evaluated Mannitol salt agar and the deoxyribonuclease (DNase) test for improving the efficiency of the tube coagulase test in resource limited settings. The efficiency of human and sheep plasma with tube coagulase tests was also evaluated.
Incremental Yield of Serial Sputum Cultures for Diagnosis of Tuberculosis among HIV Infected Smear Negative Pulmonary TB Suspects in Kampala, Uganda
(PLoS One, 2012) Ssengooba, Willy; Kiwanuka, Noah; Kateete, David P.; Katamba, Achilles; Joloba, Moses L.
Sputum culture is the gold standard for diagnosis of pulmonary tuberculosis (PTB). Although mostly used for research, culture is recommended by the World Health Organization for TB diagnosis among HIV infected smear negative PTB suspects. Even then, the number of sputum samples required remains unspecified. Here, we determined the Incremental Yield (IY) and number of samples required to diagnose an additional PTB case upon second and third serial sputum culture. Methods/Findings: This was a cross sectional study done between January and March 2011. Serial sputum samples were provided by participants within two days and cultured using Lowenstein Jensen (LJ) and Mycobacteria Growth Indicator Tube (MGIT) methods. A PTB case was defined as a positive culture on either one or both methods. The IY from the second and third serial cultures was determined and the reciprocal of the product of the fractions of IY provided the number of samples required for an additional PTB case. Of the 170 smear negative PTB suspects, 62 (36.5%) met the case definition. The IY of the second sample culture was 12.7%, 23.6% and 12.6% and for the third sample culture was 6.8%, 7.5% and 7.3% with LJ, MGIT and LJ or MGIT, respectively. The number of samples required for an additional PTB case and 95% CI upon the second sample culture were 29.9 (16.6, 156.5), 11.3 (7.6, 21.9) and 20.8 (12.5, 62.7); while for the third sample culture were 55.6 (26.4, 500.4), 35.7 (19.0, 313.8) and 36.1 (19.1, 330.9) by LJ, MGIT and LJ or MGIT respectively. Conclusions/Significance: Among HIV infected smear negative PTB suspects in Kampala, 93% of PTB cases are diagnosed upon the second serial sputum culture. The number of cultures needed to diagnose an additional PTB case, ranges from 11–30 and 35–56 by the second and third sputum samples, respectively.
Long-term dominance of Mycobacterium tuberculosis Uganda family in peri-urban Kampala-Uganda is not associated with cavitary disease
(BMC Infectious Diseases, 2013) Wampande, Eddie M.; Mupere, Ezekiel; Debanne, SaraM; Asiimwe, Benon B.; Nsereko, Mary; Mayanja, Harriet; Eisenach, Kathleen; Kaplan, Gilla; Boom, Henry W.; Gagneux, Sebastien; Joloba, Moses L.
Previous studies have shown that Mycobacterium tuberculosis (MTB) Uganda family, a sub-lineage of the MTB Lineage 4, is the main cause of tuberculosis (TB) in Uganda. Using a well characterized patient population, this study sought to determine whether there are clinical and patient characteristics associated with the success of the MTB Uganda family in Kampala. A total of 1,746 MTB clinical isolates collected from1992-2009 in a household contact study were genotyped. Genotyping was performed using Single Nucleotide Polymorphic (SNP) markers specific for the MTB Uganda family, other Lineage 4 strains, and Lineage 3, respectively. Out of 1,746 isolates, 1,213 were from patients with detailed clinical data. These data were used to seek associations between MTB lineage/sub-lineage and patient phenotypes.

Browsing by Author "Joloba, Moses L."

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