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ObjectiveThe objective of the study was to determine the diagnostic performance of the GenoQuick MTB test on heated sputum against the conventional Lowenstein-Jensen Mycobacterium tuberculosis culture as the reference method for tuberculosis diagnosis.IntroductionFast, reliable, and easy-to-use tests for tuberculosis diagnosis are essential to achieving the Sustainable Development Goal of diagnosing and treating 90% of tuberculosis patients by 2030. We evaluated the diagnostic performance of the GenoQuick MTB, a polymerase chain reaction-lateral flow test, in Uganda, a resource-constrained, high tuberculosis- and HIV-burden setting.MethodsFresh sputum samples from presumptive tuberculosis patients at Mulago Hospital were tested for M. tuberculosis using smear microscopy, GenoQuick MTB test, and Lowenstein-Jensen culture. For the GenoQuick MTB test, mycobacterial DNA was extracted by heating sputum at 95°C for 30 min while DNA amplification and detection were done following the manufacturer's protocol (Hain Lifescience, Nehren, Germany). Sensitivity, specificity, and kappa agreements were calculated against Lowenstein-Jensen M. tuberculosis culture as a reference test using STATA V12.ResultsOf the 86 tested samples, 30.2% had culture-confirmed pulmonary tuberculosis. Overall, sensitivity was higher for GenoQuick MTB (81%, 95% confidence interval: 60%-93%) than for smear microscopy (69%, 95% confidence interval: 48%-86%). Among people living with HIV, sensitivity was identical for GenoQuick MTB and smear tests (75%, 95% confidence interval: 42%-95%). Contrastingly, smear had a higher overall specificity (98%, 95% confidence interval: 91%-100%) than for GenoQuick MTB (92%, 95% confidence interval: 81%-97%). A similar trend of specificity was observed among the people living with HIV for smear microscopy (100%, 95% CI: 87%-100%) and for GenoQuick MTB (96%, 95% confidence interval: 81%-100%).ConclusionThe GenoQuick MTB test could be a potential tuberculosis diagnostic test given its higher sensitivity. Evaluation of this test in larger studies is recommended.

BackgroundIntroduction of GeneXpert MTB/RIF (Xpert) assay has constituted a major breakthrough for tuberculosis (TB) diagnostics. Several patient factors may influence diagnostic performance of Xpert including sputum quality.ObjectiveWe carried out a prospective, observational, cross-sectional study to determine the effect of sputum quality on diagnostic performance of Xpert among presumed TB patients in Uganda.MethodsWe collected clinical and demographic information and two sputum samples from participants. Staff recorded sputum quality and performed LED fluorescence microscopy and mycobacterial culture on each sample. If both smear examinations were negative, Xpert testing was performed. We calculated diagnostic yield, sensitivity, specificity, and other indicators for Xpert for each stratum of sputum quality in reference to a standard of mycobacterial culture.ResultsPatients with salivary sputum showed a trend towards a substantially higher proportion of samples that were Xpert-positive (54/286, 19%, 95% CI 15-24) compared with those with all other sputum sample types (221/1496, 15%, 95% CI 13-17). Blood-stained sputum produced the lowest sensitivity (28%; 95% CI 12-49) and salivary sputum the highest (66%; 95% CI 53-77). Specificity didn't vary meaningfully by sample types. Salivary sputum was significantly more sensitive than mucoid sputum (+13%, 95% CI +1 to +26), while blood-stained sputum was significantly less sensitive (-24%, 95% CI -42 to -5).ConclusionsOur findings demonstrate the need to exercise caution in collecting sputum for Xpert and in interpreting results because sputum quality may impact test yield and sensitivity. In particular, it may be wise to pursue additional testing should blood-stained sputum test negative while salivary sputum should be readily accepted for Xpert testing given its higher sensitivity and potentially higher yield than other sample types. These findings challenge conventional recommendations against collecting salivary sputum for TB diagnosis and could inform new standards for sputum quality.

Background. Human Pappilloma Virus (HPV) is the necessary cause of cervical cancer. A number of risk factors are believed to influence the role of HPV in the development of cervical cancer. This is so because majority of HPV infections are cleared and only a few are able to result into cancer. Chlamydia trachomatis (CT) is considered a potential cofactor in the development of cervical intraepithelial neoplasia (CIN), although different studies have produced contradicting information (Silins et al., 2005, Bellaminutti et al., 2014, and Bhatla et al., 2013). The objective of this cross-sectional study was to determine the prevalence and association of HPV-Chlamydial coinfection with cervical intraepithelial lesions and other risk factors for cervical intraepithelial lesions at a hospital in south western Uganda (MRRH). Methods. The study included 93 participants, with an age range of 25 to 80 years, from whom cervical specimens were collected and enrolment forms were completed upon consent. Experienced midwives collected one cervical smear and two endocervical swabs from each participant. The swabs were used for HPV DNA and Chlamydia trachomatis antigen testing. Data was entered in Microsoft excel and analysed using STATA 12 software. With the help of spearman’s correlation at the 0.05 level of significance, bivariate and multivariate analysis were done by logistic regression, to determine associations of risk factors to cervical lesions. Results. The results showed the prevalence of HPV-Chlamydial coinfection to be 8.6% (8/93). Positive Pap smear results were found in 60.22% (56/93) participants, most of whom had low grade squamous intraepitherial lesion (LSIL) (54.84%). HPV-Chlamydial coinfection showed a significant correlation with a positive cytology result and only relatively significantly correlated with LSIL grade of cytological positivity. HPV was found to be the risk factors associated with cervical intraepithelial lesions at MRRH. Conclusion. HPV, Chlamydia, and HPV-Chlamydial coinfection are prevalent infections and there is a likelihood of association between HPV-Chlamydial coinfection and with cervical intraepithelial lesions. This study recommends general sexually transimitted infections (STIS) screening for every woman that turns up for cervical cancer screening and a larger study, probably a multicentre study.

Summary Points * Partnerships between universities in high- and low-income countries have the potential to increase research capacity in both settings. * We describe a partnership between the Karolinska Institutet in Sweden and Makerere University in Uganda that includes a joint PhD degree program and sharing of scientific ideas and resources. * Ten years of financial support from the Swedish International Development Cooperation Agency has enabled 44 graduated PhD students and more than 500 peer-reviewed articles, the majority with a Ugandan as first author. * The collaborative research environment is addressing Ugandan health and health system priorities, in several cases resulting in policy and practice reforms. * Even though all Ugandan PhD graduates have remained in the country and 13 have embarked on postdoc training, remaining institutional challenges include developing functioning research groups, grant writing, network building at Makerere, and continued funding on both sides of the partnership., Background The Bamako Global Ministerial Forum on Research for Health emphasised the importance of developing national health research capacity in low- and middle-income countries (LMICs) as a key element in [...]

Abstract Background Determination of the prevalence and drug susceptibility of the M. tuberculosis strains is important in tuberculosis control. We determined the genetic diversity and susceptibility profiles of mycobacteria isolated from tuberculosis patients in Mbarara, South Western Uganda. Methods We enrolled, consecutively; all newly diagnosed and previously treated smear-positive TB patients aged ≥ 18 years. The isolates were characterized using regions of difference (RD) analysis and spoligotyping. Drug resistance against rifampicin and isoniazid were tested using the Genotype® MDRTBplus assay and the indirect proportion method on Lowenstein-Jensen media. HIV-1 testing was performed using two rapid HIV tests. Results A total of 125 isolates from 167 TB suspects (60% males) with a mean age 33.7 years and HIV prevalence of 67.9% (55/81) were analyzed. Majority (92.8%) were new cases while only 7.2% were retreatment cases. All the 125 isolates were identified as M. tuberculosis strict sense with the majority (92.8%) of the isolates being modern strains while seven (7.2%) isolates were ancestral strains. Spoligotyping revealed 79 spoligotype patterns, with an overall diversity of 63.2%. Sixty two (49.6%) of the isolates formed 16 clusters consisting of 2-15 isolates each. A majority (59.2%) of the isolates belong to the Uganda genotype group of strains. The major shared spoligotypes in our sample were SIT 135 (T2-Uganda) with 15 isolates and SIT 128 (T2) with 3 isolates. Sixty nine (87%) of the 79 patterns had not yet been defined in the SpolDB4.0.database. Resistance mutations to either RIF or INH were detected in 6.4% of the isolates. Multidrug resistance, INH and RIF resistance was 1.6%, 3.2% and 4.8%, respectively. The rpoβ gene mutations seen in the sample were D516V, S531L, H526Y H526D and D516V, while one strain had a Δ1 mutation in the wild type probes. There were three strains with katG (codon 315) gene mutations only while one strain showed the inhA promoter gene mutation. Conclusion The present study shows that the TB epidemic in Mbarara is caused by modern M. tuberculosis strains mainly belonging to the Uganda genotype and anti-TB drug resistance rate in the region is low.

Abstract Background About 500 new smear-positive Multidrug-resistant tuberculosis (MDR-TB) cases are estimated to occur per year in Uganda. In 2008 in Kampala, MDR-TB prevalence was reported as 1.0% and 12.3% in new and previously treated TB cases respectively. Line probe assays (LPAs) have been recently approved for use in low income settings and can be used to screen smear-positive sputum specimens for resistance to rifampicin and isoniazid in 1-2 days. Methods We assessed the performance of a commercial line probe assay (Genotype MTBDRplus) for rapid detection of rifampicin and isoniazid resistance directly on smear-positive sputum specimens from 118 previously treated TB patients in a reference laboratory in Kampala, Uganda. Results were compared with MGIT 960 liquid culture and drug susceptibility testing (DST). LPA testing was also performed in parallel in a University laboratory to assess the reproducibility of results. Results Overall, 95.8% of smear-positive specimens gave interpretable results within 1-2 days using LPA. Sensitivity, specificity, positive and negative predictive values were 100.0%, 96.1%, 83.3% and 100.0% for detection of rifampicin resistance; 80.8%, 100.0%, 100.0% and 93.0% for detection of isoniazid resistance; and 92.3%, 96.2%, 80.0% and 98.7% for detection of multidrug-resistance compared with conventional results. Reproducibility of LPA results was very high with 98.1% concordance of results between the two laboratories. Conclusions LPA is an appropriate tool for rapid screening for MDR-TB in Uganda and has the potential to substantially reduce the turnaround time of DST results. Careful attention must be paid to training, supervision and adherence to stringent laboratory protocols to ensure high quality results during routine implementation.

Abstract Background One of the challenges facing the tuberculosis (TB) control programmes in resource-limited settings is lack of rapid techniques for detection of drug resistant TB, particularly multi drug resistant tuberculosis (MDR TB). Results obtained with the conventional indirect susceptibility testing methods come too late to influence a timely decision on patient management. More rapid tests directly applied on sputum samples are needed. This study compared the sensitivity, specificity and time to results of four direct drug susceptibility testing tests with the conventional indirect testing for detection of resistance to rifampicin and isoniazid in M. tuberculosis. The four direct tests included two in-house phenotypic assays – Nitrate Reductase Assay (NRA) and Microscopic Observation Drug Susceptibility (MODS), and two commercially available tests – Genotype® MTBDR and Genotype® MTBDRplus (Hain Life Sciences, Nehren, Germany). Methods A literature review and meta-analysis of study reports was performed. The Meta-Disc software was used to analyse the reports and tests for sensitivity, specificity, and area under the summary receiver operating characteristic (sROC) curves. Heterogeneity in accuracy estimates was tested with the Spearman correlation coefficient and Chi-square. Results Eighteen direct DST reports were analysed: NRA – 4, MODS- 6, Genotype MTBDR® – 3 and Genotype® MTBDRplus – 5. The pooled sensitivity and specificity for detection of resistance to rifampicin were 99% and 100% with NRA, 96% and 96% with MODS, 99% and 98% with Genotype® MTBDR, and 99% and 99% with the new Genotype® MTBDRplus, respectively. For isoniazid it was 94% and 100% for NRA, 92% and 96% for MODS, 71% and 100% for Genotype® MTBDR, and 96% and 100% with the Genotype® MTBDRplus, respectively. The area under the summary receiver operating characteristic (sROC) curves was in ranges of 0.98 to 1.00 for all the four tests. Molecular tests were completed in 1 – 2 days and also the phenotypic assays were much more rapid than conventional testing. Conclusion Direct testing of rifampicin and isoniazid resistance in M. tuberculosis was found to be highly sensitive and specific, and allows prompt detection of MDR TB.