Grace Mirembe

The utility of handheld echocardiography for early rheumatic heart disease diagnosis: A field study

AIMS The World Heart Federation (WHF) guidelines for rheumatic heart disease (RHD) are designed for a standard portable echocardiography (STAND) machine. A recent study in a tertiary care centre demonstrated that they also had good sensitivity and specificity when modified for use with handheld echocardiography (HAND). Our study aimed to evaluate the performance of HAND for early RHD diagnosis in the setting of a large-scale field screening. METHODS AND RESULTS STAND was performed in 4773 children in Gulu, Uganda, with 10% randomly assigned to also undergo HAND. Additionally, any child with mitral or aortic regurgitation also underwent HAND. Studies were performed by experienced echocardiographers and blindly reviewed by cardiologists using 2012 WHF criteria, which were modified slightly for HAND--due to the lack of spectral Doppler capability. Paired echocardiograms were performed in 1420 children (mean age 10.8 and 53% female), resulting in 1234 children who were normal, 133 who met criteria for borderline RHD, 47 who met criteria for definite RHD, and 6 who had other diagnoses. HAND had good sensitivity and specificity for RHD detection (78.9 and 87.2%, respectively), but was most sensitive for definite RHD (97.9%). Inter- and intra-reviewer agreement ranged between 66-83 and 71.4-94.1%, respectively. CONCLUSIONS HAND has good sensitivity and specificity for diagnosis of early RHD, performing best for definite RHD. Protocols for RHD detection utilizing HAND will need to include confirmation by STAND to avoid over-diagnosis. Strategies that evaluate simplified screening protocols and training of non-physicians hold promise for more wide spread deployment of HAND-based protocols.

Handheld echocardiography versus auscultation for detection of rheumatic heart disease

BACKGROUND: Rheumatic heart disease (RHD) remains a major public health concern in developing countries, and routine screening has the potential to improve outcomes. Standard portable echocardiography (STAND) is far more sensitive than auscultation for the detection of RHD but remains cost-prohibitive in resource-limited settings. Handheld echocardiography (HAND) is a lower-cost alternative. The purpose of this study was to assess the incremental value of HAND over auscultation to identify RHD. METHODS: RHD screening was completed for schoolchildren in Gulu, Uganda, by using STAND performed by experienced echocardiographers. Any child with mitral or aortic regurgitation or stenosis plus a randomly selected group of children with normal STAND findings underwent HAND and auscultation. STAND and HAND studies were interpreted by 6 experienced cardiologists using the 2012 World Heart Federation criteria. Sensitivity and specificity of HAND and auscultation for the detection of RHD and pathologic mitral or aortic regurgitation were calculated by using STAND as the gold standard. RESULTS: Of 4773 children who underwent screening with STAND, a subgroup of 1317 children underwent HAND and auscultation. Auscultation had uniformly poor sensitivity for the detection of RHD or valve disease. Sensitivity was significantly improved by using HAND compared with auscultation for the detection of definite RHD (97.8% vs 22.2%), borderline or definite RHD (78.4% vs 16.4%), and pathologic aortic insufficiency (81.8% vs 13.6%). CONCLUSIONS: Auscultation alone is a poor screening test for RHD. HAND significantly improves detection of RHD and may be a cost-effective screening strategy for RHD in resource-limited settings.

Antiretroviral Drug Resistance Profiles and Response to Second-Line Therapy Among HIV Type 1-Infected Ugandan Children

We sought to determine the pattern of resistance-associated mutations (RAMs) among HIV-1-infected children failing first-line antiretroviral therapy (ART) and ascertain their response to second-line regimens in 48 weeks of follow-up. The design involved a cohort study within an HIV care program. We studied records of 142 children on ART with virological failure to first-line ART and switched to second-line ART with prior genotypic resistance testing. The pattern of RAMs was determined in frequency runs and the factors associated with accumulation of≥3 thymidine analogue mutations (TAMs) and K103N were determined using multivariate logistic models. Changes in weight, height, CD4, and viral load at weeks 24 and 48 after switch to second-line therapy were determined using descriptive statistics. The children were mean age 10.9±4.6 years and 55.6% were male. The commonest nucleoside reverse transcriptase inhibitor (NRTI) RAM was M184V in 129/142 (90.8%) children. TAMs,≥3 TAMs, 69 insertion complex, K65R/N, and Q151M were observed in 43.0%, 10.6%, 18.3%, 2.8%, and 2.1% of the children, respectively. The commonest nonnucleoside reverse transcriptase inhibitor (NNRTI) RAM was K103N in 72/142 (50.7%) children. The starting ART regimen was associated with accumulation of both≥3 TAMs (p=0.046) and K103N (p<0.0001), while a history of poor adherence was associated with K103N accumulation (p=0.0388). After 24 weeks and 48 weeks of follow-up on lopinavir-ritonavir based second-line ART, 86/108 (79.6%) and 84.5% (87/103) of the children had viral loads<400 copies/ml, respectively. The mean CD4 absolute count increased by 173 cells/μl and 267cells/μl at weeks 24 and 48, respectively. Increments were also observed in mean weight (1.6 kg and 4.3 kg) and height (1.8 cm and 5.8 cm) at weeks 24 and 48, respectively. Multiple RAMs were observed among HIV-1-infected children with virological failure on first-line ART with M184V and K103N most frequent. The children responded favorably to boosted PI-based second-line ART.

Brief Report: Prevalence of Latent Rheumatic Heart Disease Among HIV-Infected Children in Kampala, Uganda.

Abstract:Rheumatic heart disease (RHD) remains highly prevalent in resource-constrained settings around the world, including countries with high rates of HIV/AIDS. Although both are immune-mediated diseases, it is unknown whether HIV modifies the risk or progression of RHD. We performed screening echocardiography to determine the prevalence of latent RHD in 488 HIV-infected children aged 5–18 in Kampala, Uganda. The overall prevalence of borderline/definite RHD was 0.82% (95% confidence interval: 0.26% to 2.23%), which is lower than the published prevalence rates of 1.5%–4% among Ugandan children. There may be protective factors that decrease the risk of RHD in HIV-infected children.

Latent Rheumatic Heart Disease: Identifying the Children at Highest Risk of Unfavorable Outcome.

Background: Screening echocardiography has emerged as a potentially powerful tool for early diagnosis of rheumatic heart disease (RHD). The utility of screening echocardiography hinges on the rate of RHD progression and the ability of penicillin prophylaxis to improve outcome. We report the longitudinal outcomes of a cohort of children with latent RHD and identify risk factors for unfavorable outcomes. Methods: This was a prospective natural history study conducted under the Ugandan RHD registry. Children with latent RHD and ≥1 year of follow-up were included. All echocardiograms were re-reviewed by experts (2012 World Heart Federation criteria) for inclusion and evidence of change. Bi- and multivariable logistic regression, Kaplan-Meier analysis, and Cox proportional hazards models, as well, were developed to search for risk factors for unfavorable outcome and compare progression-free survival between those treated and not treated with penicillin. Propensity and other matching methods with sensitivity analysis were implemented for the evaluation of the penicillin effect. Results: Blinded review confirmed 227 cases of latent RHD: 164 borderline and 63 definite (42 mild, 21 moderate/severe). Median age at diagnosis was 12 years and median follow-up was 2.3 years (interquartile range, 2.0–2.9). Penicillin prophylaxis was prescribed in 49.3% with overall adherence of 84.7%. Of children with moderate-to-severe definite RHD, 47.6% had echocardiographic progression (including 2 deaths), and 9.5% had echocardiographic regression. Children with mild definite and borderline RHD showed 26% and 9.8% echocardiographic progression and 45.2% and 46.3% echocardiographic improvement, respectively. Of those with mild definite RHD or borderline RHD, more advanced disease category, younger age, and morphological mitral valve features were risk factors for an unfavorable outcome. Conclusions: Latent RHD is a heterogeneous diagnosis with variable disease outcomes. Children with moderate to severe latent RHD have poor outcomes. Children with both borderline and mild definite RHD are at substantial risk of progression. Although long-term outcome remains unclear, the initial change in latent RHD may be evident during the first 1 to 2 years following diagnosis. Natural history data are inherently limited, and a randomized clinical trial is needed to definitively determine the impact of penicillin prophylaxis on the trajectory of latent RHD.

Rheumatic Heart Disease Treatment Cascade in Uganda

Background— Rheumatic heart disease (RHD) is a leading cause of premature death and disability in low-income countries; however, few receive optimal benzathine penicillin G (BPG) therapy to prevent disease progression. We aimed to comprehensively describe the treatment cascade for RHD in Uganda to identify appropriate targets for intervention. Methods and Results— Using data from the Uganda RHD Registry (n=1504), we identified the proportion of patients in the following care categories: (1) diagnosed and alive as of June 1, 2016; (2) retained in care; (3) appropriately prescribed BPG; and (4) optimally adherent to BPG (>80% of prescribed doses). We used logistic regression to investigate factors associated with retention and optimal adherence. Overall, median (interquartile range) age was 23 (15–38) years, 69% were women, and 82% had clinical RHD. Median follow-up time was 2.4 (0.9–4.0) years. Retention in care was the most significant barrier to achieving optimal BPG adherence with only 56.9% (95% confidence interval, 54.1%–59.7%) of living subjects having attended clinic in the prior 56 weeks. Among those retained in care, however, we observed high rates of BPG prescription (91.6%; 95% confidence interval, 89.1%–93.5%) and optimal adherence (91.4%; 95% confidence interval, 88.7–93.5). Younger age, latent disease status, and access to care at a regional center were the strongest independent predictors of retention and optimal adherence. Conclusions— Our study suggests that improving retention in care—possibly by decentralizing RHD services—would have the greatest impact on uptake of antibiotic prophylaxis among patients with RHD in Uganda.

Role of Natural Autoantibodies in Ugandans With Rheumatic Heart Disease and HIV

Background Rheumatic heart disease (RHD) and HIV are prevalent diseases in sub-Saharan Africa, but little is known about their potential interrelationships. The objective of this study was to assess the prevalence of protective natural autoantibodies among patients with RHD in Uganda, and to determine whether the levels of these autoantibodies are affected by HIV status. Methods Participants were grouped according to RHD and HIV status. The three control groups (RHD − HIV −, RHD − HIV +, RHD + HIV −) were age-matched to the RHD + HIV + participants. All participants underwent HIV testing and echocardiography to evaluate for RHD. Natural autoantibody levels reactive with phosphorylcholine (PC) and malondialdehyde (MDA) were measured. Findings We enrolled 220 participants; 21 with both RHD and HIV. Ages ranged from 10 to 60 years, with female predominance (144/220, 65%). After adjusting for age and gender, HIV infection and RHD were each associated with low IgM anti-PC (HIV: p < 0.0001 and RHD: p = 0.01). A distinct HIV ∗ RHD interaction was identified (p = 0.045) with increased IgG anti-MDA levels in HIV infected subjects without RHD, whereas IgG anti-MDA levels were decreased in HIV infected subjects with RHD. Interpretation We found that HIV and RHD are associated with alterations in natural autoantibody responses previously linked to an increased risk for atherosclerosis and autoimmune inflammatory disease.

Impact of regionalisation of a national rheumatic heart disease registry: the Ugandan experience

Objectives Rheumatic heart disease (RHD) remains a major driver of cardiovascular morbidity and mortality in low-resource settings. Registry-based care for RHD has been advocated as a powerful tool to improve clinical care and track quality metrics. Data collected through an RHD registry may also reveal epidemiological and geospatial trends, as well as insight into care utilisation. Uganda established a central RHD registry at the country’s only tertiary cardiac centre in 2010. In 2014 RHD care and registry enrolment expanded to the Western region and in 2015 to the North. Here, we examine the geographical distribution of RHD cases in Uganda and the impact of registry expansion. Methods A retrospective search of the Ugandan national RHD registry was preformed to capture all cases of acute rheumatic fever or clinical RHD from January 2010 through July 2016. A geospatial analysis revealed that the density of detected cases (cases/100 000 district residents) reflected proximity to an RHD registry enrolment centre. Regionalisation improved the number of cases detected in the regions of expansion and improved retention of patients in care. Results and conclusions RHD appears to have uniform distribution throughout Uganda with geographical clustering surrounding RHD registry enrolment centres reflecting access to care, rather than differences in prevalence. Higher rates of case detection and improved retention in care with regionalisation highlight the urgent need for decentralisation of cardiovascular services. Future studies should examine sustainable models for cardiovascular care delivery, including task shifting of clinical care and echocardiography and use of telemedicine.