Anticoagulation control among patients on vitamin K antagonists in nine countries in Sub-Saharan Africa.

Vitamin K antagonists (VKA) is the primary anticoagulant in most settings of Sub-Saharan Africa. Understanding the quality of anticoagulation services in the continent is vital in optimising the intended benefits. This study assessed the quality of anticoagulation and associated factors among VKA-treated patients in nine SSA countries. We conducted a retrospective cohort study of randomly selected patients on anticoagulation from 20 clinics in Botswana, the Democratic Republic of Congo, Ethiopia, Gambia, Ghana, Mozambique, Nigeria, Tanzania, and South Africa. Eligible participants were those on VKAs for at least three months and with at least four international normalised ratios (INR) results in 2019-2021. We report the proportion of INR values in the therapeutic range, time-in-therapeutic range (TTR) using the Rosendaal method, and the proportion of patients with TTR ≥ 65% (optimal anticoagulation). The mean age was 51.1(16.1) years, and 64.2% were women. The most common indications for VKA included venous thromboembolism (29.6%), prosthetic valves (26.7%) and atrial fibrillation/flutter (30.1%). We analysed 6743 INR tests from 1011 participants, and of these, 48.5% were sub-therapeutic, 34.1% therapeutic, and 17.4% were supratherapeutic relative to disease-specific reference ranges. TTR was calculated for 660 patients using 4927 INR measurements. The median (interquartile range [IQR]) TTR was 35.8(15.9,57.2) %. Optimal anticoagulation control was evident in 19.2% of participants, varying from 2.7% in Tanzania to 23.1% in Ethiopia. The proportion of patients with TTR ≥ 65% was 15,4% for prosthetic heart valves, 21.1% for venous thromboembolism and 23.7% for atrial fibrillation or flutter. Countries with universal health coverage had higher odds of optimal anticoagulation control (adjusted odds ratio (aOR) 1.79, 95% confidence interval [CI], 1.15- 2.81, p = 0.01). Patients on VKAs for different therapeutic indications in SSA had suboptimal TTR. Universal health coverage increased the odds of achieving TTR by 79%. The evidence calls for more intensive warfarin management strategies in SSA, including providing VKA services without out-of-pocket payments.

Radiation protection knowledge and practices in interventional cardiologists practicing in Africa: a cross sectional survey.

We conducted a survey of doctors working in the cardiac catheterisation laboratories in Africa on their knowledge, attitude and practice with respect to radiation protection. Of seventy-two respondents contacted, 61 (84.7%) completed the questionnaire. Twenty-eight, (45.9%) were younger than 45 years. Thirty-seven, (60.6%) had less than 10 years of experience in the laboratory. Only 28 (45.9%) had undertaken radiation protection training. Fifty-eight, (95.1%) consistently used lead aprons. Forty-seven, (77%) reported consistently using thyroid shields. Ten (16.4%) consistently used radiation protection eyeglasses, whilst 36 (59%) never used them. Thermoluminescent Dosimeter badges were consistently used in 23 (37.7%). Forty-two, (68.9%) reported having ceiling mounted lead/acrylic shields. Level of radiation exposure in the most recent one year was ≤2 mSv in 14, between 2 and 20 mSv in 8 and between 20 and 30 mSv in 2, whilst 33 did not know their dose readings. The use of basic radiation protection tools as well as the knowledge and measurement of radiation exposure among interventional cardiologists working in Africa is low. The unavailability of some of the protective tools and a knowledge gap in terms of radiation protection and monitoring of self-exposure were some of the reasons for suboptimal self-protection against ionising radiation among our respondents. We suggest that initiatives be taken by all stakeholders to train this group of medical professionals in basic radiation protection to avoid unnecessary exposure to themselves, co-workers and patients.

Diagnosis and Management of Acute Heart Failure in Sub-Saharan Africa.

PURPOSE OF REVIEW: Acute heart failure (AHF) is a common emergency presentation in Sub-Saharan Africa (SSA). In the current review, we present the most recent data on the epidemiology of AHF in SSA and discuss recommended approaches to management in resource-limited settings, with a particular focus on primary and secondary facilities (e.g., health centers and district hospitals), where these patients often present. RECENT FINDINGS: AHF in SSA is most often due to hypertension, cardiomyopathies, and rheumatic heart disease. The etiology of AHF may be different in rural as compared with urban settings. Diagnostic tools for AHF are often lacking in SSA, especially at the first-level facilities. Point-of-care ultrasound (POCUS) and biomarker tests, such as brain natriuretic peptide (BNP), offer promise in helping to mitigate diagnostic challenges. POCUS can also help distinguish among types of heart failure and prompt the correct treatment strategy. Many of the drugs and equipment commonly used to treat AHF in resource-rich settings are lacking in SSA. However, some adaptations of commonly available materials may provide temporary alternatives. The epidemiology of AHF in SSA differs from that of high-income settings. Management of AHF at the first-level facility in SSA is an important and understudied problem. Simplified diagnostic and treatment algorithms rooted in knowledge of the local epidemiology should be developed and tested as part of broader efforts to combat cardiovascular disease in SSA.

Factors associated with perioperative mortality in children and adolescents operated for tetralogy of Fallot: A sub-Saharan experience.

BACKGROUND: Patients with tetralogy of Fallot are now surviving to adulthood with timely surgical intervention. However, many patients in low-income countries have no access to surgical intervention. This paper reports the surgical access and perioperative mortality in a sub-Saharan center that was mainly dependent on visiting teams. METHODS: We reviewed records of patients operated from January 2009 to December 2014. We examined perioperative outcomes, primarily focusing on factors associated with perioperative mortality. RESULTS: During this period, 62 patients underwent surgery. Fifty-seven (91.9%) underwent primary repair, while 5 (6.5%) underwent palliative shunt surgery. Of the five patients with shunt surgery, four ultimately underwent total repair. Eight (12.9%) patients died during the perioperative period. Factors associated with perioperative mortality include repeated preoperative phlebotomy procedures (P < .001), repeated runs and long cardiopulmonary bypass time (P < .001), and aortic cross-clamp time (P < .001), narrow pulmonary artery (PA) valve annulus diameter (P = .022), narrow distal main PA diameter (P = .039), narrow left branch PA diameter (P = .049), and narrow right PA diameter (P = .039). Of these factors, cardiopulmonary bypass time/aortic cross-clamp time and pulmonary valve annulus diameter less than three SD were independently associated with perioperative mortality. CONCLUSION: In this series of consecutive patients operated by a variety of humanitarian surgical teams, cardiopulmonary bypass time/aortic cross-clamp time, and pulmonary valve annulus diameter less than three SD were independently associated with perioperative mortality risk. As some of these factors are modifiable, we suggest that they should be considered during patient selection and at the time of surgical intervention.

Successful training of self-sufficient interventional paediatric cardiology team in a sub-Saharan setting: a multicentre collaborative model.

BACKGROUND: Most children in the Third World do not have access to treatment for heart diseases, as the priorities of health care are different from the developed countries. MATERIALS AND METHODS: Since 2009, teams supported by the Chain of Hope and Spanish medical volunteers have travelled twice a year to help develop paediatric cardiac services in the Cardiac Center in Ethiopia, undertaking four missions each year. As of December 2012, 296 procedures were performed on 287 patients. The procedures included 128 duct occlusions, 55 pulmonary valve dilations, 25 atrial septal defect closures, 14 mitral valve dilations, and others. The local staff were trained to perform a majority of these cases. RESULTS: Procedural success was achieved in 264 (89.2%). There were three deaths, five device embolisations, and three complications in mitral valve dilation. During the visits, the local staff were trained including one cardiologist, six nurses, and two technicians. The local team performed percutaneous interventions on its own after a couple of years. The goal is also to enable the local team to perform interventions independently. CONCLUSION: Training of an interventional cardiology team in a sub-Saharan setting is challenging but achievable. It may be difficult for a single centre to commit to sending frequent missions to a developing country to make a meaningful contribution to the training of local teams. In our case, coordination between the teams from the two countries helped to achieve our goals.

Percutaneous balloon dilation of severe pulmonary valve stenosis in patients with cyanosis and congestive heart failure.

OBJECTIVES: This article reports outcomes of percutaneous balloon dilation in patients with severe pulmonary valve stenosis, in particular in those treated late with cyanosis, congestive heart failure, and pericardial effusion. BACKGROUND: Percutaneous balloon dilation is the treatment of choice for pulmonary valve stenosis. Although earlier intervention may produce better results, patients may present late with congestive heart failure and cyanosis. METHODS: Fifty-five patients who underwent pulmonary valve balloon dilation, were grouped into two groups, based on the presence or absence of congestive right heart failure and/or central cyanosis. Group I included 33 patients with severe pulmonary valve stenosis, but without clinical evidence of congestive right heart failure in the form of liver enlargement, raised jugular venous pressure, and peripheral edema and/or central cyanosis and group II included 22 patients with severe pulmonary valve stenosis and congestive right heart failure and/or central cyanosis. Their outcomes were compared. RESULTS: Doppler measured transvalvar pressure gradient decreased from 110.2 ± 34.0 mm Hg before to 52.5 ± 28.7 mm Hg in group I after dilation (P < 0.001), and from 138.4 ± 32.3 mm Hg to 53.9 ± 19.3 mm Hg in group II, (P < 0.001). Complications included ventricular tachycardia/fibrillation in three patients and severe bradycardia in one patient in group II. Twelve patients in group II developed clinical and radiologic evidence of reperfusion injury/pulmonary edema within the first 24 hr of intervention and needed ventilation for 2-9 days. Three of these patients died from intractable pulmonary edema. On follow up, clinical and echocardiographic improvement parameters were similar in the two groups. CONCLUSION: Those patients with severe pulmonary valve stenosis with congestive right heart failure, especially those with pericardial effusion, ascites and cyanosis, represent an important technical and clinical challenge. They are a high-risk group with or without treatment. If they survive the procedure, they may still remain at a high risk in the first few days afterward. Maintaining their ventilator and inotropic support after balloon dilation may increase survival. However, excellent results can be obtained.

Rheumatic mitral stenosis in children: more accelerated course in sub-Saharan patients.

BACKGROUND: Mitral stenosis, one of the grave consequences of rheumatic heart disease, was generally considered to take decades to evolve. However, several studies from the developing countries have shown that mitral stenosis follows a different course from that seen in the developed countries. This study reports the prevalence, severity and common complications of mitral stenosis in the first and early second decades of life among children referred to a tertiary center for intervention. METHODS: Medical records of 365 patients aged less than 16 and diagnosed with rheumatic heart disease were reviewed. Mitral stenosis was graded as severe (mitral valve area < 1.0 cm2), moderate (mitral valve area 1.0-1.5 cm2) and mild (mitral valve area > 1.5 cm2). RESULTS: Mean age at diagnosis was 10.1 ± 2.5 (range 3-15) years. Of the 365 patients, 126 (34.5%) were found to have mitral stenosis by echocardiographic criteria. Among children between 6-10 years, the prevalence of mitral stenosis was 26.5%. Mean mitral valve area (n = 126) was 1.1 ± 0.5 cm2 (range 0.4-2.0 cm2). Pure mitral stenosis was present in 35 children. Overall, multi-valvular involvement was present in 330 (90.4%). NYHA functional class was II in 76% and class III or IV in 22%. Only 25% of patients remember having symptoms of acute rheumatic fever. Complications at the time of referral include 16 cases of atrial fibrillation, 8 cases of spontaneous echo contrast in the left atrium, 2 cases of left atrial thrombus, 4 cases of thrombo-embolic events, 2 cases of septic emboli and 3 cases of airway compression by a giant left atrium. CONCLUSION: Rheumatic mitral stenosis is common in the first and early second decades of life in Ethiopia. The course appeared to be accelerated resulting in complications and disability early in life. Echocardiography-based screening programs are needed to estimate the prevalence and to provide support for strengthening primary and secondary prevention programs.

Discrete subpulmonic membrane in association with isolated severe pulmonary valvar stenosis.

BACKGROUND: Subpulmonic membrane as a cause of right ventricular outflow tract obstruction in patients with concordant ventriculoarterial connection and intact ventricular septum is considered to be rare. CASE PRESENTATION: A 7-year-old boy was referred to a tertiary care hospital with complaints of dyspnea on moderate exertion and palpitations of about 2 years duration. Physical examination revealed parasternal lift, systolic thrill and a 4/6 ejection systolic murmur, best heard over the left 2nd intercostal space. His oxygen saturation was 88% on room air. Two-dimensional echocardiography showed a thickened pulmonary valve with fused leaflets that show severe systolic doming. There was a discrete subpulmonic membrane about 1.3 cm below the pulmonary valve annulus. Continuous wave Doppler interrogation showed peak systolic pressure gradient of 185 mmHg across the pulmonary valve. Balloon dilation of the pulmonary valve was performed and the pressure gradient came down to 50 mmHg. Follow-up transthoracic echocardiography showed residual pressure gradient of about 50-60 mmHg across the pulmonary valve. The residual pressure gradient appeared to be mainly subvalvar, as seen on the continuous wave Doppler tracing. The patient reported marked improvement in terms of exercise tolerance and subjective symptoms. CONCLUSIONS: Association of subpulmonic membrane with severe pulmonary valvar stenosis, concordant ventriculoarterial connection and intact ventricular septum is rare. When it occurs, the result of percutaneous valve dilation may be suboptimal.

Congenital absence of left pulmonary artery in association with isolated pulmonary valvular stenosis:.

Congenital absence of either of the pulmonary arteries is a rare condition but an entity known for almost one and half century. Unilateral absence of a pulmonary artery commonly occurs in association with other congenital cardiac lesions, but can also occur alone. Differential vascularity on plain chest radiograph is the usual clue to the diagnosis. Here, a 14 month old patient with congenital absence of the left pulmonary artery in association with isolated pulmonary valve stenosis is described.

Hematologic Derangements among Children with Unoperated Cyanotic Congenital Heart Disease in Ethiopia.

Background: Surgical treatment has transformed the course and outcome of congenital heart defects in high-income countries, but children with congenital heart diseases in sub-Saharan Africa, where access to cardiac surgery is limited, often experience the natural course of untreated lesions and their complications. The objective of this study was to determine the prevalence of hematologic derangements among Ethiopian children with unoperated cyanoticcongenital heart diseases, to identify factors associated with coagulopathy in this population, and to describe how these complications are managed in this setting. Methods: In this single-center cross-sectional study, we prospectively collected clinical and demographic data from children (<18 years) with cyanotic congenital heart diseases. Blood samples were collected to measure hematologic parameters. Polycythemia was defined as hematocrit >50% and thrombocytopenia as <150,000 per microliter. Results: Among 70 children recruited, the overall prevalence of polycythemia and thrombocytopenia was 63% (n=44) and 26% (n=18), respectively. On multivariate logistic regression analysis, hematocrit ≥65% (p-value=.024), and oxygen saturation <85% (p-value=.018) were independently associated with moderate or severe thrombocytopenia. Thirty-one (44%) patients had undergone therapeutic phlebotomy, and 84% (26/31) of these patients received iron supplementation. Conclusion: We report a high prevalence of polycythemia and thrombocytopenia in Ethiopian children with untreated cyanotic congenital heart diseases. There was variable implementation of iron supplementation and therapeutic phlebotomy, highlighting the need to optimize supportive management strategies in this population to mitigate the risk of life-threatening complications.

Pulmonary hemorrhage and associated risk factors among newborns admitted to a tertiary level neonatal unit in Botswana.

Introduction: Pulmonary hemorrhage (PH) is a life-threatening complication seen in very sick newborns with high morbidity and mortality. There is little data on the incidence, risk factors, and ultimate survival of newborns with pulmonary hemorrhage in sub-Saharan countries, where the healthcare provision and facility differ in many ways compared to high-income countries. Hence, this study aimed to determine the incidence, identify the risk factors, and describe the outcome of pulmonary hemorrhage in newborns in a low middle income country setting. Methods and materials: A cohort study with prospective data collection was conducted in a public, tertiary-level hospital in Botswana, the Princess Marina Hospital (PMH). All newborns admitted to the neonatal unit from 1 January 2020 to 31 December 2021 were included in the study. Data were collected using a checklist developed on the RedCap database (https//:ehealth.ub.ac.bw/redcap). The incidence rate of pulmonary hemorrhage was calculated as the number of newborns who had pulmonary hemorrhage per 1,000 newborns in the 2-year period. Group comparisons were made using X2 and Student's t-tests. Multivariate logistic regression was used to identify risk factors independently associated with pulmonary hemorrhage. Result: There were 1,350 newborns enrolled during the study period, of which 729 were male newborns (54%). The mean (SD) birth weight was 2,154(±997.5) g, and the gestational age was 34.3 (±4.7) weeks. In addition, 80% of the newborns were delivered in the same facility. The incidence of pulmonary hemorrhage was 54/1,350 {4% [95% CI (3%-5.2%)]} among the newborns admitted to the unit. The mortality rate in those diagnosed with pulmonary hemorrhage was 29/54 (53.7%). Multivariate logistic regression identified birth weight, anemia, sepsis, shock, disseminated intravascular coagulopathy (DIC), apnea of prematurity, neonatal encephalopathy, intraventricular hemorrhage, mechanical ventilation, and blood transfusion as risk factors independently associated with pulmonary hemorrhage. Conclusion: This cohort study identified a high incidence and mortality rate of pulmonary hemorrhage in newborns in PMH. Multiple risk factors, such as low birth weight, anemia, blood transfusion, apnea of prematurity, neonatal encephalopathy, intraventricular hemorrhage, sepsis, shock, DIC, and mechanical ventilation, were identified as independently associated risk factors for PH.

Vitamin K-dependent anticoagulant use and level of anticoagulation control in sub-Saharan Africa: protocol for a retrospective cohort study.

BACKGROUND: Given that vitamin K-dependent anticoagulants (VKAs) will continue to be the primary anticoagulant in Africa for a long time, understanding the quality of anticoagulation services in the continent is vital for optimising the intended benefits. Notably, a few small studies have assessed the quality of anticoagulation in sub-Saharan Africa (SSA) countries. This study will describe the current VKA use and anticoagulation control among patients in selected SSA countries. METHODS AND ANALYSIS: We plan to review the 2019 anticoagulation data of a cohort of 800 random patients from 19 selected clinics in Botswana, the Democratic Republic of Congo, Ethiopia, Gambia, Ghana, Mozambique, Nigeria, Tanzania and South Africa. We expect at least one participating site to enrol 100 participants in each country. Eligible participants will be those on VKAs for at least 3 months and with at least four international normalised ratio (INR) results. We will document the indications, type and duration of VKA use, sociodemographic factors, coexisting medical conditions, concurrent use of drugs that interact with warfarin and alcohol and tobacco products. The level of anticoagulation control will be determined by calculating the time-in-therapeutic range (TTR) using the Rosendaal and the Percent of INR in TTR methods. A TTR of less than 65% will define a suboptimal anticoagulation control. ETHICS AND DISSEMINATION: This study was approved by the Ministry of Health and Wellness Ethics Committee (HPDME13/8/1) in Botswana and local research ethics committees or institutional review boards of all participating sites. As the study collects data from existing records, sites applied for waivers of consent. We will disseminate research findings through peer-reviewed scientific publications.

Prevalence and Factors Associated with Microalbuminuria in Pediatric Patients with Type 1 Diabetes Mellitus at a Large Tertiary-Level Hospital in Botswana.

INTRODUCTION: Microalbuminuria is considered the earliest sign of diabetic nephropathy among patients with type 1 diabetes mellitus (T1DM). The prevalence of microalbuminuria among African children with T1DM is reported to be high, yet its prevalence and population-specific risk factors in Botswana are not known. AIM: This study aimed to determine the prevalence of microalbuminuria among children and young adults with T1DM in Botswana and identify factors associated with microalbuminuria in this population. METHODS: A retrospective cross-sectional study was conducted on 127 T1DM patients aged <24 years followed at a pediatric endocrinology clinic in Botswana from 2010 to 2017. Clinical, laboratory, and demographic data were collected using chart review and patient surveys. Descriptive statistics were reported as mean and standard deviation for continuous variables, and frequency and percentage for categorical variables. Prevalence of microalbuminuria was calculated as a simple proportion. Group comparison was done using two-sample independent t-test, X 2-test, or Fisher's exact test and logistic regression to assess for associations. Level of significance was set at p<0.05. RESULTS: There were a total of 71 (55.9%) females. The mean age was 18.7 (±5) years and mean duration of T1DM was 6.6 (±4.6) years. Most study participants were of African descent. The prevalence of microalbuminuria was 28.3%. Group comparison revealed gender (p= 0.040), duration of diabetes (p= 0.002), systolic blood pressure (p=0.003), baseline glycated hemoglobin (HbA1c) (p=0.009) and Tanner's stage (p=008) to be significantly associated with microalbuminuria. On binary logistic regression, only gender (p=0.039) and baseline HbA1c (p=0.039) were independently associated with the presences of microalbuminuria. CONCLUSION: This study identified a high prevalence of microalbuminuria among children and young adults with T1DM in Botswana and reaffirms the importance of early detection, glycemic control, and regular screening to prevent diabetic nephropathy.

Echocardiographic abnormalities in children and adolescents living with human immunodeficiency virus on highly active antiretroviral treatment.

BACKGROUND: The availability and use of highly active antiretroviral treatment (HAART) has turned human immunodeficiency virus (HIV) into a chronic disease, allowing patients to live much longer. OBJECTIVES: To report asymptomatic cardiac abnormalities in children and adolescents based on both conventional and tissue Doppler imaging (TDI) echocardiography. METHODS: One hundred and fifty-one patients on HAART were recruited. Demographic and clinical variables were collected through patient interviews and medical record reviews. Conventional echocardiography and TDI were performed on each patient. RESULTS: Mean age was 13.0 ± 3.2 (4.0-19.0) years. Eightythree patients (55%) were female. Age at diagnosis of HIV infection was 5.7 ± 3.3 years. Age at initiation of HAART was 7.34 ± 3.54 years, while duration of HAART was 59 ± 39.1 months. On conventional echocardiography, three cases of left ventricular (LV) systolic dysfunction, two of pulmonary hypertension and one of minimal pericardial effusion were identified. Calculation of myocardial mass index (MMI) revealed that 16 patients had abnormal values. Twenty-seven (17.9%) patients had evidence of LV diastolic dysfunction and 18 (11.9%) had right ventricular (RV) diastolic dysfunction. Nineteen (12.6%) patients had tricuspid annular systolic velocity of < 9.5 cm/s, indicating asymptomatic RV systolic dysfunction. CONCLUSIONS: While few patients had abnormalities such as reduced LV ejection fraction, pulmonary hypertension and minimal pericardial effusion detectable on conventional echocardiography, a larger proportion of patients had subtle abnormalities such as increased MMI, LV diastolic dysfunction on TDI, RV dysfunction and abnormal myocardial performance index. Such patients may need routine screening and cardiac follow up.

Clinical spectrum and prevalence of congenital heart disease in children in Botswana.

BACKGROUND: Reliable data on congenital heart disease (CHD) from diverse settings is important both for planning health systems in each country and to elucidate possible aetiologies of CHD in different settings. There is a lack of data on the clinical spectrum and prevalence of CHD in Botswana. The aim of this study was to describe the clinical spectrum and prevalence of CHD in Botswana. METHODS: This was a retrospective, descriptive, cross-sectional study of all children from birth to 15 years who had had an echocardiogram performed as an in- or out-patient at Princess Marina Hospital (PMH) between 1 January 2010 and 31 December 2012. RESULTS: Of 377 enrollees, 140 (40%) had normal echocardiographs, 170 (45%) had CHD, and 57 (15%) had an acquired lesion. In the CHD patients, median age was 0.9 years (Q1: 0.2, Q3: 4.1) and 85 (50%) were male. Ventricular septal defect (VSD) (29%), patent ductus arteriosus (18%), atrio-ventricular septal defect (AVSD) (10%) and tetralogy of Fallot (TOF) (6%) were the predominant pathologies. VSD was the most common acyanotic lesion and TOF the most common cyanotic lesion. The estimated prevalence of CHD was between 2.8 and 4.95 per 1 000 live births. CONCLUSIONS: The clinical spectrum of CHD in Botswana is similar to that observed in other African countries and in the Western world, with VSD the most common acyanotic lesion and TOF the most common cyanotic lesion. The prevalence of CHD was 2.8-4.95 per 1 000 live births, in keeping with other settings. This is the first study to describe CHD in Botswana, and it aimed to stimulate subsequent studies in this field.

Pediatric Spectrum of Allergic Diseases and Asthma in a Tertiary Level Hospital in Botswana: an Exploratory Retrospective Cross-Sectional Study.

PURPOSE: This study aims to describe the spectrum of allergic diseases of children and adolescents in a single allergy treatment centre in Botswana, over a period of 8 years. PATIENTS AND METHODS: A retrospective cross-sectional study was conducted using medical records of all patients aged 18 years or younger, seen at an allergy treatment centre in Botswana. Data were presented descriptively. Association between variables was explored by χ 2-test. RESULTS: Four hundred and seven patients with a mean age of 5.8 years (SD 4.4) at the time of presentation included 239 (58.7%) females and 365 (87.5%) black Africans. The most common diseases were asthma (n=249, 61.2%) followed by allergic rhinitis (AR) (n=232, 57.0%) and atopic dermatitis (AD) (n=165, 40.5%). One hundred and fifteen cases (46.2%) of asthmatic patients were skin prick test positive; sensitized to grass, moulds, dust mites and animal dander, in decreasing frequency, whereas those with allergic rhinitis (AR) and allergic conjunctivitis (AC) were sensitized to trees and all allergens identified in asthmatics. Concomitant asthma was diagnosed in 171 (73.7%) with AR, 71 (68.3%) with AC, 75 (45.5%) with AD and 42 (47.7%) with food allergy. The most common triggers for asthma exacerbations include upper respiratory tract infections, weather changes, and exposure to passive cigarette smoke. Paternal allergy and allergic disease in grandparents are predisposing factors for asthma (p=0.016 and p=0.001, respectively). Paternal allergy is also predisposed to AR (p=0.007), while maternal history of allergic disease was associated with AD (p=0.019). CONCLUSION: The most common chronic pediatric conditions seen in our allergic disease study were asthma, allergic rhinitis and atopic dermatitis with the most common triggers being viral upper respiratory tract infections, weather changes and exposure to cigarette smoke, all of which are modifiable risk factors. This exploratory study lays the foundation for future interventional studies that may be directed towards the spectrum of allergic diseases.

Factors associated with sub-optimal control of anticoagulation in patients with prosthetic heart valves taking oral anticoagulants in a sub-Saharan African setting.

BACKGROUND: Replacement of diseased valves reduces the morbidity and mortality rate associated with native valvular disease but comes at the expense of risking complications related to the implanted prosthetic device. Establishing the desired anticoagulation level in a sub-Saharan African setting may be a challenge. OBJECTIVES: This study was conducted to determine the challenges of maintaining a desired level of anticoagulation and factors associated with sub-optimal anticoagulation in patients with prosthetic heart valves on chronic anticoagulation. METHODS: We reviewed 73 patients who had undergone prosthetic valve replacement for chronic rheumatic valvular heart disease and were taking warfarin. The follow up ranged from one to 13 years. We studied international normalised ratio (INR) profiles of the patients for the six months preceding the study and defined optimal control as an INR of 2.5-3.5. We aimed to determine if there were factors associated with sub-optimal control of INR. RESULTS: Forty-two patients (57.5%) were female. Mean age of the participants was 21.5 ± 3.1 years (range 14-25 years). Warfarin was the anticoagulant in 55 (75.3%) of the patients and 18 (24.7%) were on combined warfarin and aspirin anticoagulation. Thirty-five (47.9%) patients had optimal control of their INR. Educational level of primary school or less, distance from follow-up medical facility of more than 300 km, quarterly or less-frequent check-up visit, and public health institution as a source of free warfarin supply were found to be significantly associated with sub-optimal control of INR. CONCLUSIONS: Educational level, distance from follow-up facility, number of follow-up visits and source of warfarin supply were found to be significantly associated with sub-optimal control of INR.