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Background: Vascular endothelial growth factor A (VEGFA) is a major angiogenic factor that plays an important role in the formation of blood vessels during embryonic development. VEGFA has been implicated in the pathophysiology of pre-eclampsia (PE), since pre-eclamptic women present with reduced levels of free circulating VEGFA. The 3' untranslated region (3'-UTR) of the VEGFA gene consists of elements that regulate the transcription and hence expression of the VEGFA protein in circulation. Hence it is suggested that variations thereof could underlie the reduced VEGFA levels observed in pre-eclamptic women. The purpose of this study was to investigate presence of the + 936C/T polymorphism, a common single nucleotide polymorphism (SNP) in the 3'-UTR of the VEGFA gene, and determine its association with PE among pregnant women in Uganda. Results: There was no significant difference observed in the allele and genotype frequencies of the + 936C/T 3' UTR-VEGFA polymorphism between pre-eclamptic and normotensive pregnant women (P > 0.05). Additionally, there was no significant difference in the median plasma levels of free VEGFA among women with the wild type, CT and TT genotypes of the + 936C/T VEGFA polymorphism (median = 0.84 pg/mL (IQR = 0.39–1.41) Vs 1.05 (0.61–1.18) Vs 1.05 (1.05–1.05) respectively, p-value = 0.7161). Conclusions: These study findings indicate that the + 936C/T 3' UTR-VEGFA polymorphism had no significant association with increased susceptibility to PE among women in Uganda. Further studies with a larger sample size are recommended. [ABSTRACT FROM AUTHOR]

Introduction: Staphylococcus epidermidis is often considered a non-pathogenic organism but it causes nosocomial infections. To distinguish invasive strains, comparative studies of patient and community isolates may offer some clues. We investigated the distribution of virulence determinants in patient isolates from Uganda. Methodology: S. epidermidis isolates were identified with the Staph API ID 32 kit. Antimicrobial susceptibility, biofilm formation and hemolysis were detected with standard procedures. Genes associated with virulence (aap, atlE, bhp, hla, hld, ica, IS256, sdrE, sea, tsst) and antimicrobial resistance (aac(6')-Ie-aph(2'')-Ia, aph(3')-IIIa, ant(4')-Ia, blaZ, mecA, vanA/vanB1) were detected by PCR. Results: S. epidermidis grew in 30 (30/50, 60%) ICU samples and 20 (20/60, 33%) community samples (one isolate per sample per patient/person). All ICU isolates (30/30, 100%) were IS256 and hld positive, 22 (22/30, 73%) were biofilm/ica positive, 21 (21/30, 70%) were hemolytic on blood agar, nine (9/30, 30%) contained atlE gene, six (6/30, 20%) hla gene, five (5/30, 17%) aap gene, and three (3/30, 10%) bhp gene. A gene encoding an aminoglycoside-modifying enzyme, aph(3')-IIIa, was highly prevalent (28/30, 93%), while blaZ (2/30, 7%), mecA (3/30, 10%), vanA (3/30, 10%) and vanB1 (3/30, 10%) were less prevalent. Of the community isolates, one (1/20, 5%) was ica positive, two (2/20, 10%) formed biofilms, and three (3/20, 15%) possessed the atlE gene. bhp, aap, IS256, hld and antimicrobial resistance genes were not detected in community isolates. Conclusions: S. epidermidis from ICU patients in Mulago Hospital is potentially virulent and could be a reservoir for antimicrobial resistant genes. [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.

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 80 o C, 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., (© 2024. The Author(s).)

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.

Objectives: The high burden of infectious complications among patients receiving haemodialysis (HD) via central venous catheters increases morbidity and mortality. This study determined the incidence of catheter-related bloodstream infections (CRBSIs), microbiological profile of causative organisms, and associated predictors in patients on chronic HD., Methods: A prospective single-centre cohort study of 121 adult patients with end-stage kidney disease was conducted from October 2019 to March 2020. Antibiotic susceptibility was determined by the Kirby-Bauer disk diffusion method. Cox proportional hazards model was used to determine predictors of CRBSI., Results: The mean age was 50 (standard deviation 14.9) years and the median duration of follow-up was 69 (interquartile range 23-124) days. At least one CRBSI was recorded for 41% of patients, at a rate of 5.2 infections per 1000 patient-days. Causative organisms were predominantly Gram-negative bacteria (60.3%), and 36.5% of all isolates were multi-drug resistant. Anaemia [hazard ratio (HR) 5.44, P= 0.019, 95% confidence interval (CI) 1.32-22.48] and previous bloodstream infection [HR 2.47, P= 0.028, 95% CI 1.10-5.54] were predictors of CRBSI., Conclusion: The high incidence of CRBSI in patients on chronic HD with predominance of Gram-negative bacteria means that catheter care bundles should include Gram-negative coverage., Competing Interests: None declared., (© 2022 The Author(s).)

Introduction: Diagnostic guidelines for Tuberculosis (TB) in HIV infected patients previously relied on microscopy where the value of initial antibiotic treatment for exclusion of pulmonary TB (PTB) was limited. New guidelines rely on the Xpert MTB Rif test (Xpert). However, the value of the antibiotic treatment remains unclear particularly in individuals who are smear-negative and Xpert-negative-given Xpert has only moderate sensitivity for smear-negative PTB. We assessed an algorithm involving initial treatment with antibiotics prior empiric TB treatment in HIV patients with presumptive PTB who were both smear and Xpert negative., Methods: We performed a prospective study with six month follow-up to establish patient response to a course of broad spectrum antibiotics prior empiric TB treatment between March 2012 and June 2013. We calculated the proportion of patients who responded to the antibiotic treatment and those who did not. We computed the crude and adjusted odds ratios with their 95% confidence intervals, for response to the antibiotic treatment on various patient characteristics. We report treatment outcomes for patients who received broad spectrum antibiotics only or who were initiated empiric TB treatment., Results: Our cohort comprised 162 smear-negative and Xpert-negative patients, of whom 59% (96 of 162) were female, 81% (131 of 162) were on antiretroviral therapy (ART) for a median of 8.7 months. Overall, 88% (141 of 160) responded to the antibiotic treatment, 8% (12 of 160) got empiric TB treatment and 4% (7 out of 160) were treated for other respiratory disease. The odds of improvement on antibiotics were lower in patients with advanced HIV disease than in patients with early HIV disease. Adjusted odds ratios were significant for HIV clinical stage (AOR; 0.038,) and duration on ART (AOR; 1.038,)., Conclusion: The majority of HIV patients with presumptive PTB with smear-negative and Xpert negative results improved on the antibiotic treatment and did not require empiric TB treatment. Initial antibiotic treatment appeared more successful in patients with less advanced HIV disease. Findings from our study suggest it is useful to initiate HIV infected patients with presumptive PTB having smear and Xpert negative results on an initial course of antibiotic treatment prior empiric TB treatment.

Aim: To characterize AmpC -beta lactamases among Enterobacteriaceae isolates from clinical samples at Mbarara Regional Referral Hospital., Study Design: Laboratory-based descriptive cross-sectional study., Place and Duration of Study: Microbiology Department, Mbarara Regional Referral Hospital and MBN clinical Laboratories, between May to September 2013., Methodology: This study included 293 Enterobacteriaceae isolates recovered from clinical specimens that included blood, urine, stool and aspirates. Amp C Beta lactamase production was determined using disc placement method for cefoxitin at a break point of <18mm. Common AmpC plasmid mediated genes were EBC, ACC, FOX, DHA, CIT and MOX were; was determined by Multiplex PCR as described by Hanson and Perez-Perez., Results: Plasmid mediated Amp C phenotype was confirmed in 107 of the 293 (36.5%) cefoxitin resistant isolates with 30 isolates having more than one gene coding for resistance. The commonest source that harbored Amp C beta lactamases was urine and E. coli was the most common Amp C producer (59.5%). The genotypes detected in this study, included EBC (n=36), FOX (n=18), ACC (n=11), CIT (n=10), DHA (n=07) and MOX (n=1)., Conclusion: Our findings showed that prevalence of Amp C beta-lactamase at MRRH was high (39.6), with EBC as the commonest genotype among Enterobacteriaceae Urine and E. coli were the commonest source and organism respectively that harbored AmpC beta-lactamases. There's rational antimicrobial therapy and antibiotic susceptibility tests should be requested by health workers especially patients presenting with urinary tract infections and bacteraemias.