The changing landscape of infective endocarditis in South Africa.

BACKGROUND: Little is known about the current clinical profile and outcomes of patients with infective endocarditis (IE) in South Africa (SA). OBJECTIVES: To provide a contemporary and descriptive overview of IE in a representative SA tertiary centre. METHODS: We conducted a retrospective review of the records of patients admitted to Groote Schuur Hospital, Cape Town, between 2009 and 2016 fulfilling universal criteria for definite or possible IE, in search of demographic, clinical, microbiological, echocardiographic, treatment and outcome information. RESULTS: A total of 105 patients fulfilled the modified Duke criteria for IE. The median age of the cohort was 39 years (interquartile range (IQR) 29 - 51), with a male preponderance (61.9%). The majority of the patients (72.4%) had left-sided native valve endocarditis, 14.3% had right-sided disease, and 13.3% had prosthetic valve endocarditis. A third of the cohort had rheumatic heart disease. Although 41.1% of patients with left-sided disease had negative blood cultures, the three most common organisms cultured in this subgroup were Staphylococcus aureus (18.9%), Streptococcus spp. (16.7%) and Enterococcus spp. (6.7%). Participants with right-sided endocarditis were younger (29 years, IQR 27 - 37) and were mainly intravenous drug users (73.3%), and the majority cultured positive for S. aureus (73.3%) with frequent septic pulmonary complications (40.0%). The overall in-hospital mortality was 16.2%, with no deaths in the group with right-sided endocarditis. Predictors of death in our patients were heart failure (odds ratio (OR) 8.16, 95% confidence interval (CI) 1.77 - 37.70; p=0.007) and age >45 years (OR 4.73, 95% CI 1.11 - 20.14; p=0.036). Valve surgery was associated with a reduction in mortality (OR 0.09, 95% CI 0.02 - 0.43; p=0.001). CONCLUSIONS: IE remains an important clinical problem in a typical teaching tertiary care centre in SA. In this setting, it continues to affect mainly young people with post-inflammatory valve disease and congenital heart disease. The in-hospital mortality associated with IE remains high. Intravenous drug-associated endocarditis caused by S. aureus is an important IE subset, comprising ~10% of all cases, which was not reported 15 years ago, and culture-negative endocarditis remains highly prevalent. Heart failure in IE carries a significant risk of death and needs a more intensive level of care in hospital. Finally, cardiac surgery was associated with reduced mortality, with the largest impact in patients with heart failure.

The changing landscape of infective endocarditis in South Africa

Background. Little is known about the current clinical profile and outcomes of patients with infective endocarditis (IE) in South Africa (SA). Objectives. To provide a contemporary and descriptive overview of IE in a representative SA tertiary centre. Methods. We conducted a retrospective review of the records of patients admitted to Groote Schuur Hospital, Cape Town, between 2009 and 2016 fulfilling universal criteria for definite or possible IE, in search of demographic, clinical, microbiological, echocardiographic, treatment and outcome information. Results. A total of 105 patients fulfilled the modified Duke criteria for IE. The median age of the cohort was 39 years (interquartile range (IQR) 29 - 51), with a male preponderance (61.9%). The majority of the patients (72.4%) had left-sided native valve endocarditis, 14.3% had right-sided disease, and 13.3% had prosthetic valve endocarditis. A third of the cohort had rheumatic heart disease. Although 41.1% of patients with left-sided disease had negative blood cultures, the three most common organisms cultured in this subgroup were Staphylococcus aureus (18.9%), Streptococcus spp. (16.7%) and Enterococcus spp. (6.7%). Participants with right-sided endocarditis were younger (29 years, IQR 27 - 37) and were mainly intravenous drug users (73.3%), and the majority cultured positive for S. aureus (73.3%) with frequent septic pulmonary complications (40.0%). The overall in-hospital mortality was 16.2%, with no deaths in the group with right-sided endocarditis. Predictors of death in our patients were heart failure (odds ratio (OR) 8.16, 95% confidence interval (CI) 1.77 - 37.70; p=0.007) and age >45 years (OR 4.73, 95% CI 1.11 - 20.14; p=0.036). Valve surgery was associated with a reduction in mortality (OR 0.09, 95% CI 0.02 - 0.43; p=0.001). Conclusions. IE remains an important clinical problem in a typical teaching tertiary care centre in SA. In this setting, it continues to affect mainly young people with post-inflammatory valve disease and congenital heart disease. The in-hospital mortality associated with IE remains high. Intravenous drug-associated endocarditis caused by S. aureus is an important IE subset, comprising ~10% of all cases, which was not reported 15 years ago, and culture-negative endocarditis remains highly prevalent. Heart failure in IE carries a significant risk of death and needs a more intensive level of care in hospital. Finally, cardiac surgery was associated with reduced mortality, with the largest impact in patients with heart failure

Shear bond strength comparison of RelyX Unicem with six other orthodontic resin adhesive systems.

Orthodontic bracket adhesion involves multistep procedures which are technique sensitive to various factors within the oral environment. RelyX Unicem is a restorative/prosthodontic adhesive material which by virtue of its one step adhesion procedure may prove to be suitable for efficient orthodontic bonding. The objective of this study was to compare the SBS of RelyX Unicem with six other known orthodontic bonding materials. Seventy extracted human premolar teeth were divided into seven groups of 10 teeth each. On each group, metal orthodontic brackets were bonded using one of the seven bonding materials: (A) Transbond XT primer and Transbond XT luting cement (B) F2000 compomer primer/adhesive (C) Transbond Plus and Transbond XT luting cement (D) RelyX Unicem (E) Prime & Bond NT and Calibra cement (F) Xeno III and Calibra cement (G) NRC + Prime & Bond NT and Calibra cement. Shear bond strength evaluation of each tooth was tested and recorded using the Instron materials testing machine. The results show that the mean SBS for RelyX Unicem is 5.38 MPa and NRC is 4.70 MPa which rates weak compared to all the other materials where the means for the SBS are within the acceptable range of 5.9 to 7.8 MPa. It appears that by reducing the number steps followed for orthodontic bracket adhesion, the SBS of the orthodontic adhesive materials becomes significantly compromised to the extent where such materials can be rejected as suitable for orthodontic bracket adhesion. RelyX Unicem and NRC were found to be unsuitable for orthodontic bracket adhesion.

Tooth width predictions in a sample of Black South Africans.

Space analysis during the mixed dentition requires prediction of the mesiodistal widths of the unerupted permanent canines and premolars and prediction tables and equations may be used for this purpose. The Tanaka and Johnston prediction equations, which were derived from a North American White sample, is one example which is widely used. This prediction equation may be inapplicable to other race groups due to racial tooth size variability. Therefore the purpose of this study was to derive prediction equations that would be applicable to Black South African subjects. One hundred and ten pre-treatment study casts of Black South African subjects were analysed from the Department of Orthodontics' records at the University of Limpopo. The sample was equally divided by gender with all subjects having Class I molar relationship and relatively well aligned teeth. The mesiodistal widths of the maxillary and mandibular canines and premolars were measured with a digital vernier calliper and compared with the measurements predicted with the Tanaka and Johnston equations. The relationship between the measured and predicted values were analysed by correlation and regression analyses. The results indicated that the Tanaka and Johnston prediction equations were not fully applicable to the Black South African sample. The equations tended to underpredict the male sample, while slight overprediction was observed in the female sample. Therefore, new equations were formulated and proposed that would be accurate for Black subjects.

An evaluation of the third cervical vertebra (C3) as a growth indicator in Black subjects.

In orthodontics, evaluation of skeletal age and growth maturation is essential in diagnosis and treatment planning. The use of hand wrist radiographs perform this function adequately. However, it is not the only method, as the body of the third cervical vertebra (C3) also provides a similar information. It may be clearly discerned on the routine cephalogram, obviating additional radiation. This study sets out to present the various morphologic changes observed radiographically in the body of C3 at different age groups. The cephalograms of one hundred and sixty two patients (79 males and 83 females) were evaluated from the records at the Medunsa Orthodontic Department. The body of C3 was studied on each film according to the criteria set by Hassel & Farman. The results showed that radiographically, the body of C3 displayed morphological changes consistent with normal skeletal maturation that indicated the usefulness of this technique in clinical and research work. This method therefore shows promise as an alternative to hand wrist growth stage evaluation.

Orthodontic treatment needs: comparison of two indices.

The Index of Orthodontic Treatment Needs (IOTN) and the Dental Aesthetic Index (DAI) were developed and both claimed to contain the aesthetic and dental components in their criteria of assessing malocclusion. This study was undertaken to assess the reliability of these two indices in assessing orthodontic treatment needs. The indices were applied to 120 pre-treatment study models selected from orthodontic patient records treated at the Department of Orthodontics, University of North Carolina, United States of America. The sample consisted of 60 African-Americans (Black) and 60 American Caucasians (White), age ranged from 12 to 16 years (Mean 13.8). The results showed that the IOTN and the DAI were highly correlated and highly associated statistically (p < 0.0001). The findings of this study indicated that the two indices could be used consistently to identify orthodontic treatment needs in different ethnic groups and are capable of classifying the subjects according to their malocclusion severity for those subjects eligible for treatment in fund constrained situation.

Eruption effects of microdontia--a case report.

A patient presented at the Department of Orthodontics, Medunsa Dental Hospital, complaining of "crooked teeth". On clinical examination it was evident that several teeth were unerupted. The absence of a normal eruption pattern of certain teeth as well as delayed eruption of others, resulted in a malocclusion.