- Red Cross Children’s Hospital
Cape Town - +21 0732176352
Rik De Decker
University of Cape Town, Paediatrics and Child Health, Faculty Member
- University of Cape Town, Zoology, Faculty Memberadd
- Recently retired paediatric cardiologist, clinical geneticist and zoologist.
Previously: Estuarine zoologistedit - Prof George Branchedit
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During a period of four months, 9,418 individuals, comprising new hospital admissions, new employees and blood donors, were tested for HbsAg and 1,212 for anti-HBs. A high incidence of positivity for both was found in the different groups... more
During a period of four months, 9,418 individuals, comprising new hospital admissions, new employees and blood donors, were tested for HbsAg and 1,212 for anti-HBs. A high incidence of positivity for both was found in the different groups under investigation. Subtyping was carried out on acutely ill patients and carriers. Sbtype ay was common in acutely ill patients and among addicts and subtype ad in nonhepatitis patients and healthy carriers. The significance of these findings and possible measures for prevention of spread of the infection are discussed.
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The incidence of the 22q11.2 deletion syndrome in children referred to the Cardiology Service at the Red Cross Children's Hospital, Cape Town, South Africa : a prospective study
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Background: Congenital heart disease (CHD) is a leading non-infectious cause of pediatric morbidity and mortality worldwide. Although the etiology of CHD is poorly understood, genetic factors including copy number variants (CNVs)... more
Background: Congenital heart disease (CHD) is a leading non-infectious cause of pediatric morbidity and mortality worldwide. Although the etiology of CHD is poorly understood, genetic factors including copy number variants (CNVs) contribute to the risk of CHD in individuals of European ancestry. The presence of rare CNVs in African CHD populations is unknown. This study aimed to identify pathogenic and likely pathogenic CNVs in South African patients with CHD. Methods: Genotyping was performed on 90 patients with nonsyndromic CHD using the Affymetrix CytoScan HD platform. These data were used to identify large, rare CNVs in known CHD-associated genes and candidate genes. Results: We identified eight CNVs overlapping known CHD-associated genes ( GATA4 , CRKL , TBX1 , FLT4 , B3GAT3 , NSD1 ) in six patients. The analysis also revealed CNVs encompassing five candidate genes likely to play a role in the development of CHD ( DGCR8 , KDM2A , JARID2 , FSTL1 , CYFIP1 ) in five patients. One ...
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In the last decade, however, a large Italian study has shed light on a possible link between SIDS and the long QT syndrome (LQTS), a genetic disorder which predisposes to cardiac arrhythmias, or sudden cardiac death. This remarkable story... more
In the last decade, however, a large Italian study has shed light on a possible link between SIDS and the long QT syndrome (LQTS), a genetic disorder which predisposes to cardiac arrhythmias, or sudden cardiac death. This remarkable story serves as a striking example of the power of genomics. It illustrates how a clear understanding of the exact genetic mechanisms of disease may lead to accurate genotype-phenotype correlations and effective therapeutic options. It has also served as a paradigm for how other inherited disorders may be studied to reveal new, more effective therapeutic possibilities.
OBJECTIVES To compare children with Down syndrome and children without Down syndrome and investigate whether there is a significant difference in the burden that is placed on the health care system between these two groups only in respect... more
OBJECTIVES To compare children with Down syndrome and children without Down syndrome and investigate whether there is a significant difference in the burden that is placed on the health care system between these two groups only in respect of the repair of congenital heart disease at Red Cross War Memorial Children's Hospital, Cape Town, South Africa. DESIGN This study is a retrospective case control review. SETTING Red Cross War Memorial Children's Hospital, Cape Town, South Africa. SUBJECTS The sample group of 50 Down syndrome children who had received cardiac surgery between January 1998 and June 2003 was compared with a control group of 50 nonsyndromic children who had received cardiac surgery during the same period. OUTCOME MEASURES Sex and diagnoses (cardiac and noncardiac), number of days spent in hospital and in ICU, complication rates, re-operation rates, early mortality rates, planned further cardiac surgery. Costs of these outcomes were not quantified in exact mone...
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Objectives: The PartneRships in cOngeniTal hEart disease (PROTEA) project aims to establish a densely phenotyped and genotyped Congenital Heart Disease (CHD) cohort for southern Africa. This will facilitate research into the epidemiology... more
Objectives: The PartneRships in cOngeniTal hEart disease (PROTEA) project aims to establish a densely phenotyped and genotyped Congenital Heart Disease (CHD) cohort for southern Africa. This will facilitate research into the epidemiology and genetic determinants of CHD in the region. This paper introduces the PROTEA project, characterizes its initial cohort, from the Western Cape Province of South Africa, and compares the proportion or “cohort-prevalences” of CHD-subtypes with international findings.Methods: PROTEA is a prospective multicenter CHD registry and biorepository. The initial cohort was recruited from seven hospitals in the Western Cape Province of South Africa from 1 April 2017 to 31 March 2019. All patients with structural CHD were eligible for inclusion. Descriptive data for the preliminary cohort are presented. In addition, cohort-prevalences (i.e., the proportion of patients within the cohort with a specific CHD-subtype) of 26 CHD-subtypes in PROTEA's pediatric c...
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Background Tetralogy of Fallot (ToF) and coarctation of the aorta (CoA) each constitute approximately 7% of congenital heart disease (CHD) births worldwide. Compared to developed countries, developing countries have a disparate level of... more
Background Tetralogy of Fallot (ToF) and coarctation of the aorta (CoA) each constitute approximately 7% of congenital heart disease (CHD) births worldwide. Compared to developed countries, developing countries have a disparate level of access to prompt diagnosis and treatment for these diseases. Computational fluid dynamics (CFD) approaches implemented on routinely available non-invasive imaging data may yield low-cost improvements to the management of these patients. Purpose The purpose of this research is to develop a patient-specific computational pipeline that allows the modelling of blood flow in diseased arteries of patients suffering from ToF and CoA. The project aims to prove the feasible use of broadly available imaging techniques - CT angiograms (CTA) and echocardiographs (echo) - for achieving this in low-to-middle income countries. The capability of the pipeline will be demonstrated through a qualitative study of the effects of different systemic to pulmonary shunt conf...
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Background Paediatric penetrating cardiac injury is extremely rare, precluding published management guidelines, therefore warranting a case-by-case approach with learning points gleaned from each case. Case summary A 7-year-old boy... more
Background Paediatric penetrating cardiac injury is extremely rare, precluding published management guidelines, therefore warranting a case-by-case approach with learning points gleaned from each case. Case summary A 7-year-old boy presented to a rural hospital with a stab wound to the chest by a Withaak (Vachellia tortilis) thorn. The patient was haemodynamically stable on presentation, but a 2 cm subcutaneous, pulsatile mass was present at the cardiac apex. Echocardiography revealed a foreign body penetrating from the apex into the heart, with evidence for a fistula between a cardiac chamber and the pulsatile mass. Angiography confirmed the existence of the fistula between the right ventricle (RV) and the pulsatile mass. A controlled extraction under general anaesthaesia via median sternotomy was performed in-theatre, with blood products and cardiac bypass on standby. The patient recovered without complications and was discharged after 4 days. Discussion Our case illustrates the l...
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Research Interests: Medicine and Wilderness
ABSTRACT The changes occurring in the benthic macrofaunal communities of the Bot River estuary, after an artificial opening of its mouth on 29 June 1983, are presented and the possible short- and long-term effects of this disturbance on... more
ABSTRACT The changes occurring in the benthic macrofaunal communities of the Bot River estuary, after an artificial opening of its mouth on 29 June 1983, are presented and the possible short- and long-term effects of this disturbance on their ecology are described. Surveys of the benthos conducted in December 1982 and May 1983, before the mouth-breaching, are compared with similar surveys afterwards: in October 1983, a week prior to reclosure of the estuary, and three months later, in January 1984. The total number of species decreased from 23 in May to 15 in October; however, only those species which contributed less than 5 % to the total biomass in May were lost. The largest reductions in species abundance and biomass were related to the collapse of the macrophyte, Ruppia maritima, which is intolerant of high salinities. The species which were reduced most were Arcuatula capensis, Melita zeylanica and Cyathura estuaria. These species were adversely affected by the loss of their attachment substrate (Arcuatula capensis), and possibly by increased predation pressure due to the reduction in macrophytic cover. In the areas not colonised by Ruppia, the dominant species exhibited an increase in densities and biomass. This phenomenon may be attributed to tidally induced currents which existed while the mouth was open, and which transported nutrients from the decaying macrophytes in the shallows to communities in the deeper waters. This assumption is strengthened by the fact that densities in the deeper areas returned to their usual low levels once closure of the mouth had eliminated these currents.In the longer term, breaching of the mouth seems to influence species composition and diversity. After an extended period of separation from the sea, the benthic macrofauna appears to develop towards that of a coastal lake. The unpredictable, catastrophic disturbance caused by opening the mouth, however, interrupts this development by eliminating the ‘lagoonal’ species and thereby also maintaining very low species diversities.
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Estuaries of the Cape This report provides historical overview on river catchment, ecology, biotic and abiotic characteristics and available information on the Klein estuary. Kleinriviersvlei is popularly known as "Hermanus... more
Estuaries of the Cape This report provides historical overview on river catchment, ecology, biotic and abiotic characteristics and available information on the Klein estuary. Kleinriviersvlei is popularly known as "Hermanus Lagoon". In some of the accounts of Kleinriviersvlei it is difficult to determine exactly to which component of the system the author is referring. However, for the purposes of this report, the estuary is that part of the system between an imaginary line joining Kettle and Pulpit points and the sea. The lagoon is the main lacustrine water body between the kettle point - Pulpit point line and the point of entry of the Kleinrivier in the east. When the system as a whole is being discussed it is referred to as kleinriviersvlei or, more simply the vlei. The vlei has its origin at the confluence of the Hartebees and Steenboks rivers south-east of Dunghye Park.
The physiological condition of the mullet, Liza richardsoni (Smith), from the closed Bot River estuary is compared with that of the same species from False Bay. Levels of protein, lipid, water and ash, as well as energy content were... more
The physiological condition of the mullet, Liza richardsoni (Smith), from the closed Bot River estuary is compared with that of the same species from False Bay. Levels of protein, lipid, water and ash, as well as energy content were determined in fish from the two environments. Protein (17,94% vs. 18,53 %) and ash levels (3,41 % vs. 4,81 %) were
Research Interests: Biology, Multidisciplinary, Fishery, Marine Fish, Estuary, and 4 moreMullet, Energy Levels, Bay, and Dry Weight
Research Interests: Genetics, Biology, Medicine, Humans, Heart, and 7 moreProteins, Gene, Phenotype, Clinical Sciences, Chromosome, DiGeorge Syndrome, and Syndrome
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Large coronary arterial fistulae (CAF) in children are rare, but occasionally haemodynamically significant lesions are found that require occlusion. Usually encountered incidentally (or in combination with other congenital cardiac... more
Large coronary arterial fistulae (CAF) in children are rare, but occasionally haemodynamically significant lesions are found that require occlusion. Usually encountered incidentally (or in combination with other congenital cardiac lesions), the exact incidence and frequency of symptomatic fistulae are unknown. Recently, transcatheter occlusion has become favoured over surgical ligation since it is safe, effective and carries few serious complications. Examples of complications include distal embolisation of the device and inadvertent obstruction of coronary arteries arising from the fistula. Placing the occluding device into the narrowest section of the fistula and using a device approximately twice the size of that diameter may prevent distal embolisation. A more unusual complication is the obstruction of coronary arteries (either arising from the fistula, or arising normally just proximal to the fistula) as a consequence of a proximally propagating thrombus in the fistula after it...
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Yet some drugs (e.g. paracetamol, salbutamol) are so commonplace in paediatric practice that it may come as a surprise that their use is indeed off-label in many circumstances. Problems may arise when an important drug in everyday... more
Yet some drugs (e.g. paracetamol, salbutamol) are so commonplace in paediatric practice that it may come as a surprise that their use is indeed off-label in many circumstances. Problems may arise when an important drug in everyday (off-label) use is unexpectedly in short supply. An example is dinoprostone, marketed in South Africa as Prostin E2 by Pfizer South Africa (but curiously not listed on their website). Its registered use in South Africa is for induction of labour (as an oral 0.5 mg tablet), yet it is commonly used in South Africa for the emergency maintenance of ductal patency in newborn babies. Dinoprostone Dinoprostone is a naturally occurring prostaglandin E2 that binds and activates the PGE2 receptor. It is often used as an emergency treatment to maintain the patency of the ductus arteriosus (PDA) in neonates with duct-dependent lesions such as certain forms of cyanotic congenital heart disease (e.g. pulmonary atresia or transposition of the great arteries) and interrup...
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BACKGROUND Heart failure (HF), the dominant form of cardiovascular disease in Africans, is mainly due to hypertension, rheumatic heart disease and cardiomyopathy. Cardiomyopathies pose a great challenge because of poor prognosis and high... more
BACKGROUND Heart failure (HF), the dominant form of cardiovascular disease in Africans, is mainly due to hypertension, rheumatic heart disease and cardiomyopathy. Cardiomyopathies pose a great challenge because of poor prognosis and high prevalence in low- and middle-income countries (LMICs). Little is known about the etiology and outcome of cardiomyopathy in Africa. Specifically, the role of myocarditis and the genetic causes of cardiomyopathy are largely unidentified in Africans. METHOD The African Cardiomyopathy and Myocarditis Registry Program (the IMHOTEP study) is a pan-African multi-centre, hospital-based cohort study, designed with the primary aim of describing the clinical characteristics, genetic causes, prevalence, management and outcome of cardiomyopathy and myocarditis in children and adults. The secondary aim is to identify barriers to the implementation of evidence-based care and provide a platform for trials and other intervention studies to reduce morbidity and mortality in cardiomyopathy. The registry consists of a prospective cohort of newly diagnosed (i.e., incident) cases and a retrospective (i.e., prevalent) cohort of existing cases from participating centres. Patients with cardiomyopathy and myocarditis will be subjected to a standardized 3-stage diagnostic process. To date, 750 patients have been recruited into the multi-centre pilot phase of the study. CONCLUSION The IMHOTEP study will provide comprehensive and novel data on clinical features, genetic causes, prevalence and outcome of African children and adults with all forms of cardiomyopathy and myocarditis in Africa. Based on these findings, appropriate strategies for management and prevention of the cardiomyopathies in LMICs are likely to emerge.
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Technological advances have led to better patient outcomes and the expansion of clinical services in paediatric cardiology. This expansion creates an ever-growing workload for clinicians, which has led to workflow and staffing issues that... more
Technological advances have led to better patient outcomes and the expansion of clinical services in paediatric cardiology. This expansion creates an ever-growing workload for clinicians, which has led to workflow and staffing issues that need to be addressed. The objective of this study was the development of a novel tool to measure the clinical workload of a paediatric cardiology service in Cape Town, South Africa: The patient encounter index is a tool designed to quantify clinical workload. It is defined as a ratio of the measured duration of clinical work to the total time available for such work. This index was implemented as part of a prospective cross-sectional study design. Clinical workload data were collected over a 10-day period using time-and-motion sampling. Clinicians were contractually expected to spend 50% of their daily workload on patient care. The median patient encounter index for the Western Cape Paediatric Cardiac Service was 0.81 (range 0.19–1.09), reflecting ...
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Tetralogy of Fallot (TOF) is the first described and most common cyanotic congenital heart anomaly that generated the first successful surgical palliation procedure and definitive intracardiac repair. Classical TOF comprises the four... more
Tetralogy of Fallot (TOF) is the first described and most common cyanotic congenital heart anomaly that generated the first successful surgical palliation procedure and definitive intracardiac repair. Classical TOF comprises the four typical features of right ventricular outflow tract obstruction (RVOTO), right ventricular hypertrophy (RVH), ventricular septal defect (VSD) and aortic dextroposition. Complex forms of the condition include TOF associated with absent pulmonary valve and TOF with pulmonary atresia (TOF-PA) with or without major aortopulmonary collateral arteries (MAPCAs). The pathophysiological understanding that the tetrad is basically the sequel of a singular abnormality of infundibular malformation, with anterior deviation of the infundibular septum, had major surgical consequences that improved survival. Diagnostic and functional imaging play a key role in the clinical and surgical management of patients with TOF. We revisit the role of traditionally employed imagin...
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Congenital heart defects are responsible for more deaths in the first year of life than any other birth defects. However, for those with access to good paediatric cardiac surgical services, most of these lives can be saved through timeous... more
Congenital heart defects are responsible for more deaths in the first year of life than any other birth defects. However, for those with access to good paediatric cardiac surgical services, most of these lives can be saved through timeous surgery. Even then, not all defects can be fully corrected; about 20% of patients either require further staged surgery or have a permanent palliative solution.
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Since all cellular development and function is controlled by our genetic make-up, it follows that our genome (all our DNA) has a fundamental influence on almost all human disease. The Human Genome Project (HGP) aimed to produce the... more
Since all cellular development and function is controlled by our genetic make-up, it follows that our genome (all our DNA) has a fundamental influence on almost all human disease. The Human Genome Project (HGP) aimed to produce the complete sequence of all the bases in all of human DNA, knowledge which should prove invaluable to the understanding of the pathogenesis and treatment of disease. However, its output must be placed in context of current and future clinical practice. Many recent genetic advances have come in spite of, or preceded, the publication of the human genome sequence in 2001. The exact aetiology of some common genetic disorders has remained frustratingly elusive, despite knowledge of the full sequence of all human DNA. Merely demonstrating an alteration of the sequence produced by the HGP is insufficient to explain human disease; complex genetic, protein and environmental interactions need to be elucidated to fully grasp the genetic underpinnings of disease. By elucidating the basic genetic aetiology of disorders, targeted therapies may be designed, based on precise knowledge of abnormal physiology. The HGP will have an ever-increasing impact on the understanding of common multifactorial disorders, in the rapid detection of disease-causing mutations and in determination of individual drug therapy.