It takes more than a machine: A pilot feasibility study of point-of-care HIV-1 viral load testing at a lower-level health center in rural western Uganda.

Barriers continue to limit access to viral load (VL) monitoring across sub-Saharan Africa adversely impacting control of the HIV epidemic. The objective of this study was to determine whether the systems and processes required to realize the potential of rapid molecular technology are available at a prototypical lower-level (i.e., level III) health center in rural Uganda. In this open-label pilot study, participants underwent parallel VL testing at both the central laboratory (i.e., standard of care) and on-site using the GeneXpert HIV-1 assay. The primary outcome was the number of VL tests completed each clinic day. Secondary outcomes included the number of days from sample collection to receipt of result at clinic and the number of days from sample collection to patient receipt of the result. From August 2020 to July 2021, we enrolled a total of 242 participants. The median number of daily tests performed on the Xpert platform was 4, (IQR = 2-7). Time from sample collection to result was 51 days (IQR = 45-62) for samples sent to the central laboratory and 0 days (IQR = 0-0.25) for the Xpert assay conducted at the health center. However, few participants elected to receive results by one of the expedited options, which contributed to similar time-to-patient between testing approaches (89 versus 84 days, p = 0.07). Implementation of a rapid, near point-of-care VL assay at a lower-level health center in rural Uganda appears feasible, but interventions to promote rapid clinical response and influence patient preferences about result receipt require further study. Trial registration: ClinicalTrials.gov Identifier: NCT04517825, Registered 18 August 2020. Available at: https://clinicaltrials.gov/ct2/show/NCT04517825.

Mortality and Cause of Death in Children With Presumptive Disseminated Tuberculosis.

BACKGROUND AND OBJECTIVES: Children experience high tuberculosis (TB)-related mortality but causes of death among those with presumptive TB are poorly documented. We describe the mortality, likely causes of death, and associated risk factors among vulnerable children admitted with presumptive TB in rural Uganda. METHODS: We conducted a prospective study of vulnerable children, defined as <2 years of age, HIV-positive, or severely malnourished, with a clinical suspicion of TB. Children were assessed for TB and followed for 24 weeks. TB classification and likely cause of death were assessed by an expert endpoint review committee, including insight gained from minimally invasive autopsies, when possible. RESULTS: Of the 219 children included, 157 (71.7%) were <2 years of age, 72 (32.9%) were HIV-positive, and 184 (84.0%) were severely malnourished. Seventy-one (32.4%) were classified as "likely tuberculosis" (15 confirmed and 56 unconfirmed), and 72 (32.9%) died. The median time to death was 12 days. The most frequent causes of death, ascertained for 59 children (81.9%), including 23 cases with autopsy results, were severe pneumonia excluding confirmed TB (23.7%), hypovolemic shock due to diarrhea (20.3%), cardiac failure (13.6%), severe sepsis (13.6%), and confirmed TB (10.2%). Mortality risk factors were confirmed TB (adjusted hazard ratio [aHR] = 2.84 [95% confidence interval (CI): 1.19-6.77]), being HIV-positive (aHR = 2.45 [95% CI: 1.37-4.38]), and severe clinical state on admission (aHR = 2.45 [95% CI: 1.29-4.66]). CONCLUSIONS: Vulnerable children hospitalized with presumptive TB experienced high mortality. A better understanding of the likely causes of death in this group is important to guide empirical management.

Evaluation of HRP2 and pLDH-based rapid diagnostic tests for malaria and prevalence of pfhrp2/3 deletions in Aweil, South Sudan.

BACKGROUND: Rapid diagnostic tests (RDT) for malaria are the primary tool for malaria diagnosis in sub-Saharan Africa but the utility of the most commonly used histidine-rich protein 2 (HRP2) antigen-based tests is limited in high transmission settings due to the long duration of positivity after successful malaria treatment. HRP2 tests are also threatened by the emergence of Plasmodium that do not carry pfhrp2 or pfhrp 3 genes. Plasmodium lactate dehydrogenase (pLDH)-based tests are promising alternatives, but less available. This study assessed the performances of HRP2 and pLDH(pan) tests under field conditions. METHODS: The study performed a prospective facility-based diagnostic evaluation of two malaria RDTs in Aweil, South Sudan, during the high transmission season. Capillary blood by fingerprick was collected from 800 children under 15 years of age with fever and no signs of severity. SD Bioline HRP2 and CareStart pLDH(pan) RDTs were performed in parallel, thick and thin smears for microscopy were examined, and dried blood was used for PCR testing. RESULTS: Using microscopy as the gold standard, the sensitivity of both tests was estimated at > 99%, but the specificity of each was lower: 55.0% for the pLDH test and 61.7% for the HRP2 test. When using PCR as the gold standard, the sensitivity of both tests was lower than the values assessed using microscopy (97.0% for pLDH and 96.5% for HRP2), but the specificity increased (65.1% for pLDH and 72.9% for HRP2). Performance was similar across different production lots, sex, and age. Specificity of both the pLDH and HRP2 tests was significantly lower in children who reported taking a therapeutic course of anti-malarials in the 2 months prior to enrollment. The prevalence of pfhrp2/3 deletions in the study population was 0.6%. CONCLUSIONS: The low specificity of the pLDH RDT in this setting confirms previous results and suggests a problem with this specific test. The prevalence of pfhrp2/3 deletions in the study area warrants continued monitoring and underscores the relevance of assessing deletion prevalence nationally. Improved malaria RDTs for high-transmission environments are needed.

Permethrin-treated baby wraps for the prevention of malaria: results of a randomized controlled pilot study in rural Uganda.

BACKGROUND: Progress against malaria has stalled and may even be slipping backwards in high-burden countries. This is due to a range of factors including insecticide resistance and mosquito feeding behaviours that limit contact with widely-employed interventions including long-lasting insecticidal nets and indoor-residual spraying. Thus, further innovations in malaria control are urgently needed. METHODS: The pilot was a randomized, placebo-controlled pilot study of permethrin-treated baby wraps-known locally as lesus-in children 6-18 months of age at a single site in rural western Uganda. Fifty mother-infant pairs were assigned to permethrin-treated or untreated lesus in a 1:1 allocation. Participants and clinical staff were blinded to group assignments through use of sham treatment and re-treatment of lesus. Participants attended scheduled clinic visits every 2 weeks for a total 12 weeks. The primary outcome of interest was the safety of the intervention, assessed as changes in the frequency of use, rates of discontinuation, and incidence of adverse events, such as skin rash. Secondary outcomes included acceptability and feasibility of the intervention as measured through participant satisfaction and completion of study activities, respectively. RESULTS: Overall, rates of retention and participation were relatively high with 86.0% (43 of 50) of participants completing all scheduled visits, including 18 (75.0%) and 25 (96.2%) in the intervention and control arms respectively. By the conclusion of the 12-week follow-up period, one adverse event (0.35 events per 100 person-weeks, one-sided 95% CI 0.0-1.65) was reported. Satisfaction with the lesu was high in both groups. In each study arm, there were five incident RDT positive results, but the only PCR-positive results were observed in the control group (n = 2). CONCLUSIONS: Permethrin-treated baby wraps were well-tolerated and broadly acceptable. Adverse events were infrequent and mild. These findings support future trials seeking to determine the efficacy of treated wraps to prevent P. falciparum malaria infection in young children as a complementary tool to existing household-based interventions. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04102592, Registered 25 September 2019. Available at: https://clinicaltrials.gov/ct2/show/NCT04102592.

Population Pharmacokinetics and Significant Under-Dosing of Anti-Tuberculosis Medications in People with HIV and Critical Illness.

Critical illness from tuberculosis (TB) bloodstream infection results in a high case fatality rate for people living with human immunodeficiency virus (HIV). Critical illness can lead to altered pharmacokinetics and suboptimal drug exposures. We enrolled adults living with HIV and hospitalized with sepsis, with and without meningitis, in Mbarara, Uganda that were starting first-line anti-TB therapy. Serum was collected two weeks after enrollment at 1-, 2-, 4-, and 6-h post-dose and drug concentrations quantified by validated LC-MS/MS methods. Non-compartmental analyses were used to determine total drug exposure, and population pharmacokinetic modeling and simulations were performed to determine optimal dosages. Eighty-one participants were enrolled. Forty-nine completed pharmacokinetic testing: 18 (22%) died prior to testing, 13 (16%) were lost to follow-up and one had incomplete testing. Isoniazid had the lowest serum attainment, with only 4.1% achieving a target exposure over 24 h (AUC0-24) of 52 mg·h/L despite appropriate weight-based dosing. Simulations to reach target AUC0-24 found necessary doses of rifampin of 1800 mg, pyrazinamide of 2500-3000 mg, and for isoniazid 900 mg or higher. Given the high case fatality ratio of TB-related critical illness in this population, an early higher dose anti-TB therapy should be trialed.

Surveillance of Plasmodium falciparum pfcrt haplotypes in southwestern uganda by high-resolution melt analysis.

BACKGROUND: Chloroquine (CQ) resistance is conferred by mutations in the Plasmodium falciparum CQ resistance transporter (pfcrt). Following CQ withdrawal for anti-malarial treatment, studies across malaria-endemic countries have shown a range of responses. In some areas, CQ sensitive parasites re-emerge, and in others, mutant haplotypes persist. Active surveillance of resistance mutations in clinical parasites is essential to inform treatment regimens; this effort requires fast, reliable, and cost-effective methods that work on a variety of sample types with reagents accessible in malaria-endemic countries. METHODS: Quantitative PCR followed by High-Resolution Melt (HRM) analysis was performed in a field setting to assess pfcrt mutations in two groups of clinical samples from Southwestern Uganda. Group 1 samples (119 in total) were collected in 2010 as predominantly Giemsa-stained slides; Group 2 samples (125 in total) were collected in 2015 as blood spots on filter paper. The Rotor-Gene Q instrument was utilized to assess the impact of different PCR-HRM reagent mixes and the detection of mixed haplotypes present in the clinical samples. Finally, the prevalence of the wild type (CVMNK) and resistant pfcrt haplotypes (CVIET and SVMNT) was evaluated in this understudied Southwestern region of Uganda. RESULTS: The sample source (i.e. Giemsa-stained slides or blood spots) and type of LCGreen-based reagent mixes did not impact the success of PCR-HRM. The detection limit of 10- 5 ng and the ability to identify mixed haplotypes as low as 10 % was similar to other HRM platforms. The CVIET haplotype predominated in the clinical samples (66 %, 162/244); however, there was a large regional variation between the sample groups (94 % CVIET in Group 1 and 44 % CVIET in Group 2). CONCLUSIONS: The HRM-based method exhibits the flexibility required to conduct reliable assessment of resistance alleles from various sample types generated during the clinical management of malaria. Large regional variations in CQ resistance haplotypes across Southwestern Uganda emphasizes the need for continued local parasite genotype assessment to inform anti-malarial treatment policies.

Immunogenicity and safety of fractional doses of yellow fever vaccines: a randomised, double-blind, non-inferiority trial.

BACKGROUND: Stocks of yellow fever vaccine are insufficient to cover exceptional demands for outbreak response. Fractional dosing has shown efficacy, but evidence is limited to the 17DD substrain vaccine. We assessed the immunogenicity and safety of one-fifth fractional dose compared with standard dose of four WHO-prequalified yellow fever vaccines produced from three substrains. METHODS: We did this randomised, double-blind, non-inferiority trial at research centres in Mbarara, Uganda, and Kilifi, Kenya. Eligible participants were aged 18-59 years, had no contraindications for vaccination, were not pregnant or lactating, had no history of yellow fever vaccination or infection, and did not require yellow fever vaccination for travel. Eligible participants were recruited from communities and randomly assigned to one of eight groups, corresponding to the four vaccines at standard or fractional dose. The vaccine was administered subcutaneously by nurses who were not masked to treatment, but participants and other study personnel were masked to vaccine allocation. The primary outcome was proportion of participants with seroconversion 28 days after vaccination. Seroconversion was defined as post-vaccination neutralising antibody titres at least 4 times pre-vaccination measurement measured by 50% plaque reduction neutralisation test (PRNT50). We defined non-inferiority as less than 10% decrease in seroconversion in fractional compared with standard dose groups 28 days after vaccination. The primary outcome was measured in the per-protocol population, and safety analyses included all vaccinated participants. This trial is registered with ClinicalTrials.gov, NCT02991495. FINDINGS: Between Nov 6, 2017, and Feb 21, 2018, 1029 participants were assessed for inclusion. 69 people were ineligible, and 960 participants were enrolled and randomly assigned to vaccine manufacturer and dose (120 to Bio-Manguinhos-Fiocruz standard dose, 120 to Bio-Manguinhos-Fiocruz fractional dose, 120 to Chumakov Institute of Poliomyelitis and Viral Encephalitides standard dose, 120 to Chumakov Institute of Poliomyelitis and Viral Encephalitides fractional dose, 120 to Institut Pasteur Dakar standard dose, 120 to Institut Pasteur Dakar fractional dose, 120 to Sanofi Pasteur standard dose, and 120 to Sanofi Pasteur fractional dose). 49 participants had detectable PRNT50 at baseline and 11 had missing PRNT50 results at baseline or 28 days. 900 were included in the per-protocol analysis. 959 participants were included in the safety analysis. The absolute difference in seroconversion between fractional and standard doses by vaccine was 1·71% (95% CI -2·60 to 5·28) for Bio-Manguinhos-Fiocruz, -0·90% (-4·24 to 3·13) for Chumakov Institute of Poliomyelitis and Viral Encephalitides, 1·82% (-2·75 to 5·39) for Institut Pasteur Dakar, and 0·0% (-3·32 to 3·29) for Sanofi Pasteur. Fractional doses from all four vaccines met the non-inferiority criterion. The most common treatment-related adverse events were headache (22·2%), fatigue (13·7%), myalgia (13·3%) and self-reported fever (9·0%). There were no study-vaccine related serious adverse events. INTERPRETATION: Fractional doses of all WHO-prequalified yellow fever vaccines were non-inferior to the standard dose in inducing seroconversion 28 days after vaccination, with no major safety concerns. These results support the use of fractional dosage in the general adult population for outbreak response in situations of vaccine shortage. FUNDING: The study was funded by Médecins Sans Frontières Foundation, Wellcome Trust (grant no. 092654), and the UK Department for International Development. Vaccines were donated in kind.

Comparison of Capillary Versus Venous Blood for the Diagnosis of Plasmodium falciparum Malaria Using Rapid Diagnostic Tests.

We enrolled 250 febrile children in western Uganda to compare the results of malaria rapid diagnostic tests (RDTs) when using capillary vs venous blood. Participants were tested with 4 different RDT types. Polymerase chain reaction testing was performed as the reference standard. Sensitivity and specificity were broadly similar across RDT types and sampling method. Agreement between sample type was high, ranging from 0.95 to 0.99. When following the manufacturer's recommended interpretation, only 5 tests would have resulted in a different clinical diagnosis. These results demonstrate that malaria RDTs perform similarly when using capillary or venous blood in febrile children with Plasmodium falciparum malaria.

Point-of-Care Approaches for Meningitis Diagnosis in a Low-Resource Setting (Southwestern Uganda): Observational Cohort Study Protocol of the "PI-POC" Trial.

BACKGROUND: A timely differential diagnostic is essential to identify the etiology of central nervous system (CNS) infections in children, in order to facilitate targeted treatment, manage patients, and improve clinical outcome. OBJECTIVE: The Pediatric Infection-Point-of-Care (PI-POC) trial is investigating novel methods to improve and strengthen the differential diagnostics of suspected childhood CNS infections in low-income health systems such as those in Southwestern Uganda. This will be achieved by evaluating (1) a novel DNA-based diagnostic assay for CNS infections, (2) a commercially available multiplex PCR-based meningitis/encephalitis (ME) panel for clinical use in a facility-limited laboratory setting, (3) proteomics profiling of blood from children with severe CNS infection as compared to outpatient controls with fever yet not severely ill, and (4) Myxovirus resistance protein A (MxA) as a biomarker in blood for viral CNS infection. Further changes in the etiology of childhood CNS infections after the introduction of the pneumococcal conjugate vaccine against Streptococcus pneumoniae will be investigated. In addition, the carriage and invasive rate of Neisseria meningitidis will be recorded and serotyped, and the expression of its major virulence factor (polysaccharide capsule) will be investigated. METHODS: The PI-POC trial is a prospective observational study of children including newborns up to 12 years of age with clinical features of CNS infection, and age-/sex-matched outpatient controls with fever yet not severely ill. Participants are recruited at 2 Pediatric clinics in Mbarara, Uganda. Cerebrospinal fluid (for cases only), blood, and nasopharyngeal (NP) swabs (for both cases and controls) sampled at both clinics are analyzed at the Epicentre Research Laboratory through gold-standard methods for CNS infection diagnosis (microscopy, biochemistry, and culture) and a commercially available ME panel for multiplex PCR analyses of the cerebrospinal fluid. An additional blood sample from cases is collected on day 3 after admission. After initial clinical analyses in Mbarara, samples will be transported to Stockholm, Sweden for (1) validation analyses of a novel nucleic acid-based POC test, (2) biomarker research, and (3) serotyping and molecular characterization of S. pneumoniae and N. meningitidis. RESULTS: A pilot study was performed from January to April 2019. The PI-POC trial enrollment of patients begun in April 2019 and will continue until September 2020, to include up to 300 cases and controls. Preliminary results from the PI-POC study are expected by the end of 2020. CONCLUSIONS: The findings from the PI-POC study can potentially facilitate rapid etiological diagnosis of CNS infections in low-resource settings and allow for novel methods for determination of the severity of CNS infection in such environment. TRIAL REGISTRATION: ClinicalTrials.gov NCT03900091; https://clinicaltrials.gov/ct2/show/NCT03900091. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/21430.

Dengue in Western Uganda: a prospective cohort of children presenting with undifferentiated febrile illness.

BACKGROUND: The spatial distribution and burden of dengue in sub-Saharan Africa remains highly uncertain, despite high levels of ecological suitability. The goal of this study was to describe the epidemiology of dengue among a cohort of febrile children presenting to outpatient facilities located in areas of western Uganda with differing levels of urbanicity and malaria transmission intensity. METHODS: Eligible children were first screened for malaria using rapid diagnostic tests. Children with a negative malaria result were tested for dengue using a combination NS1/IgM/IgG rapid test (SD Bioline Dengue Duo). Confirmatory testing by RT-PCR was performed in a subset of participants. Antigen-capture ELISA was performed to estimate seroprevalence. RESULTS: Only 6 of 1416 (0.42%) children had a positive dengue rapid test, while none of the RT-PCR results were positive. ELISA testing demonstrated reactive IgG antibodies in 28 (2.2%) participants with the highest prevalence seen at the urban site in Mbarara (19 of 392, 4.9%, p < 0.001). CONCLUSIONS: Overall, these findings suggest that dengue, while present, is an uncommon cause of non-malarial, pediatric febrile illness in western Uganda. Further investigation into the eocological factors that sustain low-level transmission in urban settings are urgently needed to reduce the risk of epidemics.

Effect of high-dose rifampicin on efavirenz pharmacokinetics: drug-drug interaction randomized trial.

BACKGROUND: High-dose rifampicin is considered to shorten anti-TB treatment duration but its effect on antiretroviral metabolism is unknown. OBJECTIVES: To assess the effect of doubling the rifampicin dose (to 20 mg/kg/day, R20) on efavirenz pharmacokinetics (PK) in HIV/TB coinfected patients. METHODS: Open-label Phase 2 drug-drug interaction randomized trial. Pulmonary TB, ART-naive adults were randomized to R20 and either efavirenz 600 mg (EFV600) or 800 mg (EFV800), or rifampicin 10 mg/kg/day (R10) and EFV600 with a 1:1:1 ratio. Patients were first started on TB treatment and 2-4 weeks later started on ART. They were switched to R10 and EFV600 after 8 weeks. Full PK sampling was done 4 weeks (on rifampicin) and 24 weeks (off rifampicin) after ART initiation. Transaminases, plasma HIV-1 RNA and sputum cultures were monitored. The efavirenz geometric mean ratio (GMR) of AUC at 4 and 24 weeks after ART initiation within the same patient was calculated in each arm and its 90% CI was compared with a preset range (0.70-1.43). RESULTS: Of 98 enrolled patients (32 in the R20EFV600 arm, 33 in the R20EFV800 arm and 33 in the R10EFV600 arm), 87 had full PK sampling. For the R20EFV600, R20EFV800 and R10EFV600 arms, GMRs of efavirenz AUC were 0.87 (90% CI: 0.75-1.00), 1.12 (90% CI: 0.96-1.30) and 0.96 (90% CI: 0.84-1.10). Twelve weeks after ART initiation, 78.6%, 77.4% and 72.4% of patients had HIV-1 RNA below 100 copies/mL and 85.7%, 86.7% and 80.0% had Week 8 culture conversion, respectively. Two patients per arm experienced a severe increase in transaminases. CONCLUSIONS: Doubling the rifampicin dose had a small effect on efavirenz concentrations and was well tolerated.

Evaluation of OMNIgene Sputum and Ethanol Reagent for Preservation of Sputum Prior to Xpert and Culture Testing in Uganda.

Xpert MTB/RIF (Xpert) and culture are the most reliable methods for tuberculosis diagnosis but are still poorly accessible in many low-resource countries. We aimed to assess the effects of OMNIgene Sputum (OM-S) and ethanol in preserving sputum for Xpert and OM-S for mycobacterial growth indicator tube (MGIT) testing over periods of 15 and 8 days, respectively. Sputum samples were collected from newly diagnosed smear-positive patients. For Xpert, pooled samples were split into 5 aliquots: 3 for Xpert on days 0, 7, and 15 without additive and 2 with either OM-S or ethanol at day 15. For MGIT, 2 aliquots were tested without preservative and 2 with OM-S at 0 and 8 days. Totals of 48 and 47 samples were included in the analysis for Xpert and culture. With Xpert, using day 0 as a reference, untreated samples stored for 7 and 15 days showed concordances of 45/46 (97.8%) and 46/48 (95.8%). For samples preserved with OM-S or ethanol for 15 days compared with untreated samples processed at day 0 or after 15 days, OM-S concordances were 46/48 (95.8%) and 47/48 (97.9%), while those of ethanol were 44/48 (91.7%) and 45/48 (93.8%). With MGIT, concordances between untreated and OM-S-treated samples were 21/41 (51.2%) at day 0 and 21/44 (47.7%) at day 8. In conclusion, Xpert equally detected tuberculosis in OM-S-treated and untreated samples up to 15 days but showed slightly lower detection in ethanol-treated samples. Among OM-S-treated samples, MGIT positivity was significantly lower than in untreated samples at both time points.

Utility of Clinical and Laboratory Decision Rules in Identifying Bacterial Meningitis Among Children with Suspicion of Central Nervous System Infections in a Malaria-Endemic Area, Mbarara, Uganda.

Several decision rules combining clinical and biological parameters have been proposed to distinguish bacterial from aseptic meningitis, but have not been evaluated in Africa. In children hospitalized with suspected central nervous system infections in Uganda, we found that the Bacterial Meningitis Score and Meningitest showed lower performance than in European children, and that a decision rule designed specifically using parameters associated with bacterial meningitis also showed inadequate diagnostic performance for clinical use.

Antimicrobial treatment practices among Ugandan children with suspicion of central nervous system infection.

Acute central nervous system (CNS) infections in children in sub-Saharan Africa are often fatal. Potential contributors include late presentation, limited diagnostic capacity and inadequate treatment. A more nuanced understanding of treatment practices with a goal of optimizing such practices is critical to prevent avoidable case fatality. We describe empiric antimicrobial treatment, antibiotic resistance and treatment adequacy in a prospective cohort of 459 children aged two months to 12 years hospitalised for suspected acute CNS infections in Mbarara, Uganda, from 2009 to 2012. Among these 459 children, 155 had a laboratory-confirmed diagnosis of malaria (case-fatality rate [CFR] 14%), 58 had bacterial infections (CFR 24%) and 6 children had mixed malaria and bacterial infections (CFR 17%). Overall case fatality was 18.1% (n = 83). Of 219 children with laboratory-confirmed malaria and/or bacterial infections, 182 (83.1%) received an adequate antimalarial and/or antibiotic on the day of admission and 211 (96.3%) within 48 hours of admission. The proportion of those receiving adequate treatment was similar among survivors and non-survivors. All bacterial isolates were sensitive to ceftriaxone except one Escherichia coli isolate with extended-spectrum beta-lactamase (ESBL). The observed high mortality was not a result of inadequate initial antimicrobial treatment at the hospital. The epidemiology of CNS infection in this setting justifies empirical use of a third-generation cephalosporin, however antibiotic resistance should be monitored closely.

Risk Factors for Vaginal Colonization and Relationship between Bacterial Vaginal Colonization and In-Hospital Outcomes in Women with Obstructed Labor in a Ugandan Regional Referral Hospital.

INTRODUCTION: The proportion of women with severe maternal morbidity from obstructed labor is between 2 and 12% in resource-limited settings. Maternal vaginal colonization with group B streptococcus (GBS), Escherichia coli, and Enterococcus spp. is associated with maternal and neonatal morbidity. It is unknown if vaginal colonization with these organisms in obstructed labor women is associated with poor outcomes. OBJECTIVES: To determine whether vaginal colonization with GBS, E. coli, or Enterococcus is associated with increased morbidity among women with obstructed labor and to determine the risk factors for colonization and antibiotic susceptibility patterns. METHODS: We screened all women presenting in labor to Uganda's Mbarara Regional Referral Hospital maternity ward from April to October 2015 for obstructed labor. Those meeting criteria had vaginal swabs collected prior to Cesarean delivery and surgical antibiotic prophylaxis. Swabs were inoculated onto sterile media for routine bacterial culture and antimicrobial susceptibility testing. RESULTS: Overall, 2,168 women were screened and 276 (13%) women met criteria for obstructed labor. Vaginal swabs were collected from 272 women (99%), and 170 (64%) were colonized with a potential pathogen: 49% with E. coli, 5% with GBS, and 8% with Enterococcus. There was no difference in maternal and fetal clinical outcomes between those colonized and not colonized. The number of hours in labor was a significant independent risk factor for vaginal colonization (aOR 1.02, 95% CI 1.00-1.03, P=0.04). Overall, 38% of GBS was resistant to penicillin; 61% of E. coli was resistant to ampicillin, 4% to gentamicin, and 5% to ceftriaxone and cefepime. All enterococci were ampicillin and vancomycin susceptible. CONCLUSION: There was no difference in maternal or neonatal morbidity between women with vaginal colonization with E. coli, GBS, and Enterococcus and those who were not colonized. Duration of labor was associated with increased risk of vaginal colonization in women with obstructed labor.

Xpert MTB/RIF diagnosis of childhood tuberculosis from sputum and stool samples in a high TB-HIV-prevalent setting.

The Xpert MTB/RIF assay is a major advance for diagnosis of tuberculosis (TB) in high-burden countries but is limited in children by their difficulty to produce sputum. We investigated TB in sputum and stool from children with the aim of improving paediatric TB diagnosis. A prospective cohort of children with presumptive TB, provided two sputum or induced sputum at enrolment in a regional referral hospital in Uganda. Stool was collected from those started on TB treatment. All specimen were tested for Xpert MTB/RIF, mycobacteria growth indicator tube (MGIT), Lowenstein Jensen cultures and microscopy (except stool). We compared TB detection between age categories and assessed the performance of Xpert MTB/RIF in sputum and stool. Of the 392 children enrolled, 357 (91.1%) produced at least one sputum sample. Sputum culture yield was 13/357 (3.6%): 3/109 (2.6%), 3/89 (3.2%), 3/101 (2.6%) and 4/44 (8.2%) among children of < 2, 2-5, ≥ 5-10 and > 10 years, respectively (p = 0.599). Xpert MTB/RIF yield was 14/350 (4.0%): 3/104 (2.9%), 4/92 (4.3%), 3/88 (2.9%) and 4/50 (.0%), respectively (p = 0.283). Sensitivity and specificity of Xpert MTB/RIF in sputum against sputum culture were 90.9% (95% CI 58.7-99.8) and 99.1% (99.1-99.8). In stool, it was 55.6% (21.2-86.3) and 98.2% (98.2-100) against Xpert MTB/RIF and culture in sputum. Only a minority of children had microbiologically confirmed TB with a higher proportion in children above 10 years. Although sensitivity of Xpert MTB/RIF in stool was low, with good optimization, it might be a good alternative to sputum in children.

Detection of Plasmodium Species by High-Resolution Melt Analysis of DNA from Blood Smears Acquired in Southwestern Uganda.

Microscopic diagnosis of malaria using Giemsa-stained blood smears is the standard of care in resource-limited settings. These smears represent a potential source of DNA for PCR testing to confirm Plasmodium infections or for epidemiological studies of archived samples. Therefore, we assessed the use of DNA extracts from stained blood smears for the detection of Plasmodium species using real-time PCR. We extracted DNA from archived blood smears and corresponding red blood cell pellets collected from asymptomatic children in southwestern Uganda in 2010. We then performed real-time PCR followed by high-resolution melting (HRM) to identify Plasmodium species, and we compared our results to those of microscopy. We analyzed a total of 367 blood smears and corresponding red blood cell pellets, including 185 smears (50.4%) that were positive by microscopy. Compared to microscopy, PCR-HRM analysis of smear DNA had a sensitivity of 93.0% (95% confidence interval [CI], 88.2 to 96.2%) and a specificity of 96.7% (95% CI, 93.0 to 98.8%), and PCR-HRM analysis of pellet DNA had a sensitivity of 100.0% (95% CI, 98.0 to 100.0%) and a specificity of 94.0% (95% CI, 89.4 to 96.9%). Identification of positive PCR-HRM results to the species level revealed Plasmodium falciparum (92.0%), Plasmodium ovale (5.6%), and Plasmodium malariae (2.4%). PCR-HRM analysis of DNA extracts from Giemsa-stained thick blood smears or corresponding blood pellets had high sensitivity and specificity for malaria diagnosis, compared to microscopy. Therefore, blood smears can provide an adequate source of DNA for confirmation of Plasmodium species infections and can be used for retrospective genetic studies.

Evaluation of the SD Bioline TB Ag MPT64 test for identification of Mycobacterium tuberculosis complex from liquid cultures in Southwestern Uganda.

BACKGROUND: To confirm presence of Mycobacterium tuberculosis complex, some tuberculosis culture laboratories still rely on para-nitrobenzoic acid (PNB), a traditional technique that requires sub-culturing of clinical isolates and two to three weeks to give results. Rapid identification tests have improved turnaround times for mycobacterial culture results. Considering the challenges of the PNB method, we assessed the performance of the SD Bioline TB Ag MPT64 assay by using PNB as gold standard to detect M. tuberculosis complex from acid-fast bacilli (AFB) positive cultures. OBJECTIVES: The aim of this study was to determine the sensitivity, specificity and turnaround time of the SD MPT64 assay for identification of M. tuberculosis complex, in a setting with high prevalence of tuberculosis and HIV. METHODS: A convenience sample of 690 patients, with tuberculosis symptoms, was enrolled at Epicentre Mbarara Research Centre between April 2010 and June 2011. The samples were decontaminated using NALC-NaOH and re-suspended sediments inoculated in Mycobacterium Growth Indicator Tubes (MGIT) media, then incubated at 37 °C for a maximum of eight weeks. A random sample of 50 known negative cultures and 50 non-tuberculous mycobacteria isolates were tested for specificity, while sensitivity was based on AFB positivity. The time required from positive culture to reporting of results was also assessed with PNB used as the gold standard. RESULTS: Of the 138 cultures that were AFB-positive, the sensitivity of the SD MPT64 assay was 100.0% [95% CI: 97.3 - 100] and specificity was 100.0% (95% CI, 96.4 - 100). The median time from a specimen receipt to confirmation of strain was 10 days [IQR: 8-12] with SD MPT64 and 24 days [IQR: 22-26] with PNB. CONCLUSION: The SD MPT64 assay is comparable to PNB for identification of M. tuberculosis complex and reduces the time to detection.

Carriage prevalence and serotype distribution of Streptococcus pneumoniae prior to 10-valent pneumococcal vaccine introduction: A population-based cross-sectional study in South Western Uganda, 2014.

BACKGROUND: Information on Streptococcus pneumoniae nasopharyngeal (NP) carriage before the pneumococcal conjugate vaccine (PCV) introduction is essential to monitor impact. The 10-valent PCV (PCV10) was officially introduced throughout Ugandan national childhood immunization programs in 2013 and rolled-out countrywide during 2014. We aimed to measure the age-specific Streptococcus pneumoniae carriage and serotype distribution across all population age groups in the pre-PCV10 era in South Western Uganda. METHODS: We conducted a two-stage cluster, age-stratified, cross-sectional community-based study in Sheema North sub-district between January and March 2014. One NP swab was collected and analyzed for each participant in accordance with World Health Organization guidelines. RESULTS: NP carriage of any pneumococcal serotype was higher among children <2years old (77%; n=387) than among participants aged ≥15years (8.5%; n=325) (chi2 p<0.001). Of the 623 positive cultures, we identified 49 serotypes among 610 (97.9%) isolates; thirteen (2.1%) isolates were non-typeable. Among <2years old, serotypes 6A, 6B, 14, 15B, 19F and 23F accounted for half of all carriers. Carriage prevalence with PCV10 serotypes was 29.4% among individuals aged <2years (n=387), 23.4% in children aged 2-4years (n=217), 11.4% in 5-14years (n=417), and 0.4% among individuals ≥15years of age (n=325). The proportion of carried pneumococci serotypes contained in PCV10 was 38.1% (n=291), 32.8% (n=154), 29.4% (n=156), and 4.4% (n=22) among carriers aged <2years, 2-4years, 5-14years and ≥15years, respectively. DISCUSSION: In Sheema district, the proportion of PCV10 serotypes was low (<40%), across all age groups, especially among individuals aged 15years or older (<5%). PCV10 introduction is likely to impact transmission among children and to older individuals, but less likely to substantially modify pneumococcal NP ecology among individuals aged 15years or older.