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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.

Background: Staphylococcus aureus (S. aureus) often colonizes the human skin, upper respiratory and genital tracts. In the female genital tract, it can be passed on to the newborn during vaginal delivery leading to either ordinary colonization, or neonatal infections notably umbilical stump sepsis, scalded skin syndrome, arthritis, or bacteraemia/sepsis. These infections are mediated by staphylococcal virulence factors such as (i) Staphylococcal Enterotoxins A, B, C, D, and E encoded by the sea, seb, sec, sed, see genes, (ii) Exfoliative Toxins A and B encoded by the eta and etb genes, (iii) Toxic Shock Syndrome Toxin 1 (TSST-1) encoded by the tst gene, (iv) Panton-Valentine Leukocidin (PVL) encoded by the pvl gene, and (v) Hemolysins alpha and delta encoded by the hla and hld genes, respectively. We determined the prevalence of S. aureus possessing one or more virulence factor genes and of methicillin resistant Staphylococcus aureus (MRSA) in this population. Methods: This was a cross-sectional study, which used 85 S. aureus isolates from the Chlorohexidine (CHX) clinical trial study in Uganda. The isolates had been obtained by culturing vaginal swabs (VS) from 1472 women in labour, frozen at minus 80oC, then thawed, sub-cultured, and tested for the selected virulence genes sea, seb, sec, sed, see eta, etb, tst, pvl, hla and hld, and for the methicillin resistance determining gene (mecA). Data were analyzed using SPSS version 20. Results: Of the 85 S. aureus isolates 13 (15.3%) were positive for one or more virulence factor genes, as follows: pvl 9/85 (10.6%), hld 5/85 (5.9%), sea 1/85 (1.2%) and seb genes 1/85 (1.2%). The other virulence genes (sec, sed, see, eta, etb, hla and tst) were not detected in any of the isolates. MRSA was detected in 55.3% (47/85) of the isolates, but only two of these carried the pvl virulence gene. Conclusion: This study demonstrated that 15% of the S. aureus colonizing the female lower genital tract of mothers in labour in central Uganda carried one or more virulence genes, mostly pvl, indicating potential for newborn infection with S. aureus acquired in the maternal birth canal. More than half of the isolates were MRSA. [ABSTRACT FROM AUTHOR]

Introduction: Dimorphic fungi cause infection following the inhalation of spores into the pulmonary system. In the lower respiratory tract, the conidia transform into yeasts, which are engulfed by alveolar macrophages and may be destroyed without disease manifestation. However, in some immunocompromised individuals, they may persist and cause active fungal disease characterized by formation of granulomas in the infected tissues, which may mimic Mycobacterium tuberculosis (MTB). Objective: To determine the prevalence of pulmonary dimorphic fungal infections among HIV/AIDS patients with non‐TB chronic cough at Mulago National Referral and Teaching Hospital in Kampala, Uganda. Methods: Sputum samples were collected from 175 consented HIV/AIDS patients attending the immuno‐suppression syndrome (ISS) clinic at the hospital. Upon Xpert MTB/RIF sputum testing, 21 patients tested positive for MTB, and these were excluded from further analysis. The other 154 sputum negative samples were then subjected to PCR for dimorphic fungi at MBN Clinical Laboratories. Singleplex PCR was used to detect the target sequences in selected respective genes of each dimorphic fungal species of interest. DNA amplicons were detected based on gel electrophoresis. Results: Dimorphic fungi were detected in 16.2% (25/154) of the studied population. Of these 9.1% (14/154) had Blastomyces dermatitidis and 7.1% (11/154) had Talaromyces marneffei. The remaining 84% of the studied participants had no dimorphic fungi. Histoplasma capsulatum, Coccidioides immitis and Paracoccidioides brasiliensis were not detected in any of the participants. Conclusion: Dimorphic fungi (B. dermatitidis and T. marneffei) were found in 16.2% of the HIV/AIDS patients with non‐TB chronic cough in Kampala, Uganda. We recommend routine testing for these pathogens among HIV/AIDS patients with chronic cough. [ABSTRACT FROM AUTHOR]

Hematological cancers, including Leukemias and Lymphomas, and their associated chemotherapy and disease-specific factors, are linked to impaired granulocyte function and numbers, increasing the risk of opportunistic infections, often presenting as fever. Human cytomegalovirus (HCMV) is one of the significant opportunistic infections in these patients, but limited data exists on its seroprevalence and active infection burden among febrile hematological cancer patients in Uganda. We conducted a cross-sectional study from June to August 2017 at the Uganda Cancer Institute (UCI). Blood samples from 161 febrile hematological cancer patients were collected. HCMV exposure was assessed using indirect enzyme-linked immunosorbent assay for IgG and IgM antibodies, and active infection was confirmed with PCR testing and gel electrophoresis. IgG positivity indicated previous exposure, while positive IgM or PCR results indicated active infection. Overall, HCMV seroprevalence based on IgG and/or IgM positivity was 106/161 (66%). IgG alone, IgM alone, and combined IgG/IgM positivity prevalence rates were 57/161 (35.4%), 22/161 (13.6%), and 27/161 (16.7%), respectively. HCMV DNA PCR was positive in 5 of the 161 (3%) samples. Among PCR-positive patients, one (20%) was positive for IgG alone, two (40%) for IgM alone, and two (40%) for both IgG and IgM. Active infection based on positive IgM and HCMV DNA PCR was found in 23 of the 161 (14.3%) patients. Two-thirds of febrile patients with hematological malignancies in Uganda had been exposed to HCMV infection, with 14.3% showing active infection. Routine testing for active HCMV infection among febrile hematological cancer patients at the UCI is essential for timely and appropriate antiviral treatment., Importance: In this paper, we demonstrated that over two-thirds of feverish patients with blood cancers such as leukemia at the Uganda Cancer Institute are already exposed to a type of virus infection called the human cytomegalovirus (HCMV), and 14% of the patients have active disease due to this virus. This was confirmed through finding blood samples testing positive for a type of protective antibody called IgM and also upon virus DNA detection in the blood of those patients. Routine testing for this virus is not usually done in the study settings. Our findings reveal and emphasize the importance of routinely testing blood samples for active infection with this virus among the feverish patients with blood cancers in the study settings, and prompt initiation of antiviral treatment of the actively infected patients.

The geographic and evolutionary origins of the SARS-CoV-2 Omicron variant (BA.1), which was first detected mid-November 2021 in Southern Africa, remain unknown. We tested 13,097 COVID-19 patients sampled between mid-2021 to early 2022 from 22 African countries for BA.1 by real-time RT-PCR. By November-December 2021, BA.1 had replaced the Delta variant in all African sub-regions following a South-North gradient, with a peak Rt of 4.1. Polymerase chain reaction and near-full genome sequencing data revealed genetically diverse Omicron ancestors already existed across Africa by August 2021. Mutations, altering viral tropism, replication and immune escape, gradually accumulated in the spike gene. Omicron ancestors were therefore present in several African countries months before Omicron dominated transmission. These data also indicate that travel bans are ineffective in the face of undetected and widespread infection.