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Background Medical exposure to ionizing radiation has increased due to an increase in the number of computerized tomography (CT) scan examinations performed. The International Commission on Radiological Protection (ICRP) recommends indication-based diagnostic reference levels (IB-DRLs) as an effective tool that aids in optimizing CT scan radiation doses. In many low-income settings, there is a lack of IB-DRLs to support optimization of radiation doses. Objective To establish typical DRLs for common CT scan indications among adult patients in Kampala, Uganda. Methodology: A cross sectional study design was employed involving 337 participants enrolled from three hospitals using systematic sampling. The participants were adults who had been referred for a CT scan. The typical DRL of each indication was determined as the median value of the pooled distribution of CTDIvol (mGy) data and the median value of the pooled distribution of total DLP (tDLP)(mGy.cm) data from three hospitals. Comparison was made to anatomical, and indication based DRLs from other studies. Results 54.3% of the participants were male. The following were typical DRLs for: acute stroke (30.17mGy and 653mGy.cm); head trauma (32.04mGy and 878mGy.cm); interstitial lung diseases/ high resolution chest CT scan (4.66mGy and 161mGy.cm); pulmonary embolism (5.03mGy and 273mGy.cm); abdominopelvic lesion (6.93mGy and 838mGy.cm) and urinary calculi (7.61mGy and 975mGy.cm). Indication based total Dose Length Product (tDLP) DRLs was lower than tDLP DRLs of a whole anatomical region by 36.4% on average. Most of the developed typical IB-DLP DRLs were lower or comparable to values from studies in Ghana and Egypt in all indications besides urinary calculi while they were higher than values in a French study in all indications besides acute stroke and head trauma. Conclusion Typical IB-DRLs is a good clinical practice tool for optimization of CT doses and therefore recommended for use to manage CT radiation dose. The developed IB-DRLs varied from international values due to differences in selection of CT scan parameters and standardization of CT imaging protocols may narrow the variation. This study can serve as baseline for establishment of national indication-based CT DRLs in Uganda.

IntroductionThe prevalence of cardiovascular disease (CVD) is rising in Sub-Saharan Africa, but it is not known whether current risk assessment tools predict coronary atherosclerosis in the region. Furthermore, sex-specific performance and interaction with HIV serostatus has not been well studied.MethodsThis cross-sectional study compared ASCVD risk scores and detectable coronary artery calcium (CAC>0) by sex in Kampala, Uganda (n=200). The cohort was enriched for persons living with HIV, and all participants had at least one CVD risk factor. We fit log binomial regression models and constructed ROC curves to assess the correlation between ASCVD scores and CAC>0.ResultsThe mean age was 56. 62% were female and 50% of both men and women were living with HIV. The median 10-year ASCVD risk score was significantly higher in men (11.0%, IQR 7.6-19.4%) than in women (5.1%, IQR 3.2-8.7%), although the prevalence of CAC>0 was similar (8.1 vs 10.5%, p=0.63). Each 10% increase in ASCVD risk was associated with increased risk of CAC>0 in men (PR 1.59, 95% CI 1.00-2.55, p=0.05) but not women (PR 1.15, 95% CI 0.44-3.00, p=0.77). ROC curves demonstrated an AUC of 0.57 for women vs 0.70 for men. Adjustment for HIV serostatus improved the predictive value of ASCVD in women only (AUC 0.78, p=0.02).ConclusionsASCVD risk score did not correlate with the presence of CAC in women. When HIV status was added to the ASCVD risk score, correlation with CAC was improved in women but not in men.

Background Epilepsy is one of the most common neurological conditions in children worldwide. Its presentation is heterogeneous, with diverse underlying aetiology, clinical presentation, and prognosis. Structural brain abnormalities are among the recognized causes of epilepsy. Brain Magnetic Resonance Imaging (MRI) is the imaging modality of choice for epilepsy workup. We aimed to determine the prevalence and describe the structural abnormalities identified in the brain MRI studies performed on children with epilepsy from two urban hospitals in Kampala, Uganda. Methods This was a cross-sectional descriptive study performed at two urban hospital MRI centres. The study population was 147 children aged 1 day to 17 years with confirmed epilepsy. Brain MRI was performed for each child and a questionnaire was used to collect clinical data. Results The prevalence of structural abnormalities among children with epilepsy was 74.15% (109 out of 147). Of these, 68.81% were male, and the rest were female. Among these, the majority, 40.14% (59 of 144) were aged 1 month to 4 years. Acquired structural brain abnormalities were the commonest at 69.22% with hippocampal sclerosis (HS) leading while disorders of cortical development were the most common congenital causes. An abnormal electroencephalogram (EEG) was significant for brain MRI abnormalities among children with epilepsy with 95% of participants with an abnormal EEG study having epileptogenic structural abnormalities detected in their brain MRI studies. Conclusion and recommendation Two-thirds of children with epilepsy had structural brain abnormalities. Abnormal activity in the EEG study was found to positively correlate with abnormal brain MRI findings. As such, EEG study should be considered where possible before MRI studies as a determinant for children with epilepsy who will be having imaging studies done in the Ugandan setting.

ObjectivesTo examine the relationship between pericardial fat (PCF) and cardiac structure and function among HIV-infected patients in the sub-Saharan African country of Uganda. People living with HIV (PLHIV) have altered fat distribution and an elevated risk for heart failure. Whether altered quantity and radiodensity of fat surrounding the heart relates to cardiac dysfunction in this population is unknown.MethodsOne hundred HIV-positive Ugandans on antiretroviral therapy were compared with 100 age and sex-matched HIV-negative Ugandans; all were >45 years old with >1 cardiovascular disease risk factor. Subjects underwent ECG-gated non-contrast cardiac CT and transthoracic echocardiography with speckle tracking strain imaging. Multivariable linear and logistic regression models were used to explore the association of PCF with echocardiographic outcomes.ResultsMedian age was 55% and 62% were female. Compared with uninfected controls, PLHIV had lower body mass index (27 vs 30, p=0.02) and less diabetes (26% vs 45%, p=0.005). Median left ventricular (LV) ejection fraction was 67%. In models adjusted for traditional risk factors, HIV was associated with 10.3 g/m2 higher LV mass index (LVMI) (95% CI 3.22 to 17.4; p=0.005), 0.87% worse LV global longitudinal strain (GLS) (95% CI −1.66 to −0.07; p=0.03) and higher odds of diastolic dysfunction (OR 1.96; 95% CI 0.95 to 4.06; p=0.07). In adjusted models, PCF volume was significantly associated with increased LVMI and worse LV GLS, while PCF radiodensity was associated with worse LV GLS (all pConclusionsIn Uganda, HIV infection, PCF volume and density are associated with abnormal cardiac structure and function.

Introduction Diagnostic Reference Levels (DRLs), typically set at the 75th percentile of the dose distribution from surveys conducted across a broad user base using a specified dose-measurement protocol, are recommended for radiological examinations. There is a need to develop and implement DRLs as a standardisation and optimisation tool for the radiological protection of patients at Computed Tomography (CT) facilities. Methods This was a retrospective cross-sectional study conducted in seven (7) different CT scan facilities in which participants were recruited by systematic random sampling. The study variables were dose length product (DLP) and volume-weighted CTDI (CTDIvol) for the radiation doses for head, chest, abdomen and lumbar spine CT examinations. The DRLs for CTDIvol and DLP were obtained by calculating the 3rd quartiles of the radiation doses per study site by anatomical region. The national diagnostic reference levels were determined by computation of DRLs using the 75th centile of the median values. Results A total of 574 patients were examined with an average age of 47.1 years. For CTDIvol estimates; there was a strong positive significant relationship between the CTDIvol and examination mAs (rs = 0.9017, p-value s = 0.0.7708, p-value s = 0.6812, p-value s = 0.5493, p-value Conclusion This study confirmed the need to optimize the CT scan parameters in order to lower the national DRLs. This can be achieved by extensive training of all the CT scan radiographers on optimizing the CT scan acquisition parameters. Continuous dose audits are also advised with new equipment or after every three years to ensure that values out of range are either justified or further investigated.

Introduction Little is known about the epidemiology of coronary artery disease (CAD) in sub‐Saharan Africa, where the majority of people living with HIV (PLHIV) live. We assessed the association of HIV with CAD and explored relationships with monocyte activation in sex‐stratified analyses of older PLHIV and people without HIV (PWOH) in Uganda. Methods The Ugandan Study of HIV effects on the Myocardium and Atherosclerosis (mUTIMA) follows 100 PLHIV on antiretroviral therapy (ART) and 100 age‐ and sex‐matched PWOH controls in Kampala, Uganda; all >45 years of age with >1 cardiovascular disease risk factor. At the year 2 exam (2017–2019), 189 participants had available coronary calcium score and 165 had coronary CT angiography (CCTA) for this analysis. A subset of participants (n = 107) had both CCTA and fresh whole blood flow cytometry for monocyte phenotyping. Results Median age was 57.8 years and 63% were females. Overall, 88% had hypertension, 37% had diabetes and 4% were smokers. Atherosclerotic cardiovascular disease (ASCVD) risk was modestly higher for PWOH, but not statistically significant (median 10‐year ASCVD risk 7.2% for PLHIV vs. 8.6% for PWOH, p = 0.09). Median duration of ART was 12.7 years and 86% had suppressed viral load. Despite a high prevalence of risk factors, only 34/165 (21%, 95% CI 15–28%) had any coronary plaque. After adjustment for ASCVD risk score, HIV status was not associated with CAD (OR 0.55, 95% CI 0.23–1.30) but was associated with more severe CAD (segment severity score>3) among those with disease (OR 10.9, 95% CI 1.67–70.45). Females had a trend towards higher odds of CAD among PLHIV (OR 4.1, 95% CI 0.4–44.9), but a trend towards lower odds of CAD among PWOH (OR 0.30; 95% CI 0.07–1.3; HIV*sex interaction p = 0.019). CAD was positively correlated with classical monocytes (r = 0.3, p = 0.012) and negatively correlated with CX3CR1 expression (r = –0.31, p = 0.011) in PLHIV and negatively correlated with patrolling monocytes (r = –0.36, p = 0.031) and tissue factor expression (r = –0.39, p = 0.017) in PWOH. Conclusions Our results suggest that HIV may be associated more with severity rather than the presence of CAD in Uganda. Sex differences in the HIV effect suggest that tailored CAD prevention strategies may be required in this setting.

Medical exposures to ionizing radiation constitute nearly half of the total radiation exposures from all sources. The higher utilization of imaging services is happening all over the world, Uganda inclusive. We sought to establish the relationship between adult patient anthropometric measurements and computed tomography scan exposure variables. This was a hospital-based cross-sectional study conducted in three selected hospitals performing adult CT scan examinations. A total of 176 adult patients who presented for head, abdominal, cardiac CT—calcium score and cardiac angiogram were recruited in the study. Data was collected using a piloted standardized research protocol for establishing diagnostic reference values. The data collected were weight, height, age and sex with CT scan variables. Data were analyzed using Spearman’s rank correlation coefficient and Wilcoxon rank-sum tests. This study was also approved by the ethics committee. The key findings showed that the examination, reference and total mAs were associated with significant positive associations with the anthropometric characteristics namely; weight, height and BMI as opposed to sex and age. The findings also revealed that males were generally exposed to higher doses for Head and Cardiac CT studies with females receiving higher doses for abdominal examinations only.

ObjectivesTo compare the prevalence of detectable coronary artery calcium (CAC) among higher risk, older people living with HIV (PLWH) and uninfected persons in Uganda versus the USA, and second to explore associations of CAC with HIV-specific variables and biomarkers of inflammation.MethodsThis cross-sectional study of 430 total subjects compared 100 PLWH on antiretroviral therapy and 100 age-matched and sex-matched HIV-uninfected controls in Uganda with 167 PLWH on antiretroviral therapy and 63 uninfected controls in the USA. Multivariable logistic regression was used to examine associations with detectable CAC (CAC >0).ResultsCompared with US subjects, Ugandans were older (mean age 56 vs 52 years) and were more likely to have diabetes (36% vs 3%) and hypertension (85% vs 36%), but were less likely to be male (38% vs 74%) or smokers (4% vs 56%). After adjustment for HIV serostatus, age, sex and traditional risk factors, Ugandans had substantially lower odds of CAC >0 (adjusted OR 0.07 (95% CI 0.03 to 0.17), p0 in either country (p>0.1). Among all PLWH, nadir CD4 count was associated with the presence of CAC, and among Ugandans soluble intercellular adhesion molecule (p=0.044), soluble CD163 (p=0.004) and oxidised low-density lipoprotein (p=0.043) were all associated with the presence of CAC.ConclusionsUgandans had a dramatically lower prevalence of any coronary calcification compared with US subjects. The role of HIV infection and inflammation as risk factors for subclinical coronary disease in sub-Saharan Africa merits further investigation.

Background: Globally, road traffic accidents are a major cause of death and disability. The developing countries bear a disproportionately large share of the RTAs which account for about 85% of the deaths. Most of these RTAs result in head injury, which globally, most scholars and medical practitioners consider a significant economic, social and medical problem. In Mulago National referral hospital, RTA is the leading cause of surgical admission. Objective: To describe the cranial computed tomography (CT) scan findings in adults following RTA in Mulago hospital. Methods: Using CT, detailed analysis of 178 adult patients with head injury following RTA was performed. Data was analyzed using SPSS version 16 and presented in tables and graphs. Data recorded included socio-demographic characteristics, clinical and CT variables. Results: Seventy seven percent of the respondents were between 18- 39 years. 52.6% of patients had open head injury. Headache was the most common clinical variable followed by dizziness and aphasia. The most common CT characteristic was extra cerebral haemorrhage followed by brain oedema and raised Intra-cranial pressure (ICP). Intra-cerebral haemorrhage was commonest in the frontal lobe followed by parietal lobe. Conclusion: Public health interventions like advocacy and education of the population on safe and responsible road usage should be emphasized to reduce on RTAs. Keywords: Computed tomography scan, road traffic accidents, head injury, Uganda

Road traffic accidents (RTAs) are a major global public health problem and are now a recognized neglected pandemic. Head injuries cause immediate death in 25% of acute trauma. We conducted this study to determine the immediate outcomes in adult with head injury following RTA. A prospective study was conducted among 178 adult patients and followed up for two weeks to determine immediate outcomes. Multivariate logistic regression analysis was used to determine predictor variables of immediate outcome. Majority had moderate disability (38.2%), then severe disability (25.8%) and good recovery (24.7%) at two weeks. Persistent vegetative state and death occurred in 2% and 9% of patients respectively. Sixty-three percent of patients had favourable outcome. Convulsions, intracerebral haemorrhage had significant p-values at bivariate analysis (0.019, 0.008 respectively) at GCS. Vomiting, convulsions, extra cerebral haemorrhage and intracerebral haemorrhage had significant association P values (0.000, 0.001, 0.000 and 0.000 respectively) at two weeks by GOS. Level of consciousness (p-value = 0.000), intracerebral haemorrhage (p = 0.003), skull fractures (p = 0.001) and surgery (p = 0.016) were statistically significant at multivariate analysis. GCS and GOS were important in assessment of immediate outcomes at 2 weeks but GOS was a more reliable assessment tool.