Browsing by Subject "Therapeutics"

Now showing 1 - 9 of 9
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    A cost-effective strategy for primary prevention of acute rheumatic fever and rheumatic heart disease in children with pharyngitis
    (2013) Irlam, James H; Mayosi, Bongani M; Engel, Mark E; Gaziano, Thomas A
    Primary prevention of acute rheumatic fever (ARF) and rheumatic heart disease (RHD) in children depends on prompt and effective diagnosis and treatment of pharyngitis at the primary level of care. Cost-effectiveness modeling shows that the most cost-effective strategy for primary prevention in South Africa (SA) is to use a simple symptomatic clinical decision rule (CDR) to diagnose pharyngitis in children presenting at the primary level of care and then to treat them with a single dose of intramuscular penicillin. Treat All and CDR2+ strategies are affordable and simple and miss few cases of streptococcal pharyngitis at the primary level of care. The CDR2+ strategy is the most cost-effective for primary prevention of ARF and RHD in urban SA and should complement primordial and secondary prevention efforts.
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    Antimicrobial susceptibility of organisms causing community-acquired urinary tract infections in Gauteng Province, South Africa
    (2013) Lewis, David A; Gumede, Lindy Y E; Van der Hoven, Louis A; De Gita, Gloria N; De Kock, Elsabe J E; De Lange, Telsa; Maseko, Venessa; Kekana, Valentia; Smuts, Francois P; Perovic, Olga
    BACKGROUND: Patients with community-acquired urinary tract infections (UTIs) frequently present to healthcare facilities in South Africa (SA). AIM: To provide information on UTI aetiology and antimicrobial susceptibility of pathogens. METHODS: We recruited women with UTI-related symptoms, who tested positive for ≥2 urine dipstick criteria (proteinuria, blood, leucocytes or nitrites) at 1 public and 5 private primary healthcare facilities in 2011. Demographic and clinical data were recorded and mid-stream urine (MSU) specimens were cultured. UTI pathogens were Gram-stained and identified to species level. Etest-based antimicrobial susceptibility testing was performed for amoxicillin/clavulanic acid, cefixime, cefuroxime, ciprofloxacin, fosfomycin, levofloxacin, nitrofurantoin, norfloxacin and trimethoprim/sulphamethoxazole. RESULTS: Of the 460 women recruited, 425 MSU samples were processed and 204 UTI pathogens were identified in 201 samples. Most pathogens were Gram-negative bacilli (GNB) (182; 89.2%) and 22 (10.8%) were Gram-positive cocci (GPC). Escherichia coli was the most frequent GNB (160; 79.6%), while Enterococcus faecalis was the predominant GPC (8; 4.0%). The UTI pathogens had similar susceptibility profiles for fosfomycin (95.5%; 95% confidence interval (CI) 92.6 - 98.4), the 3 fluoroquinolones (94.1%; 95% CI 90.8 - 97.4), nitrofurantoin (91.7%; 95% CI 87.8 - 95.6), cefuroxime (90.1%; 95% CI 86.0 - 94.3) and cefixime (88.2%; 95% CI 83.7 - 92.6). UTI pathogens were less susceptible to amoxicillin/clavulanic acid (82.8%; 95% CI 77.5 - 88.0) when compared with fluoroquinolones and fosfomycin. Trimethoprim/ sulphamethoxazole was the least efficacious antimicrobial agent (44.3% susceptible; 95% CI 37.4 - 51.2). CONCLUSION: This study provides relevant data for the empirical treatment of community-acquired UTIs in SA.
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    Case report: Severe central nervous system manifestations associated with aberrant efavirenz metabolism in children: the role of CYP2B6 genetic variation
    (2015) Abrams, Elaine
    BackgroundEfavirenz, widely used as part of antiretroviral drug regimens in the treatment of paediatric human immunodeficiency virus infection, has central nervous system side effects. We describe four children presenting with serious, persistent central nervous system adverse events who were found to have elevated plasma efavirenz concentrations as a result of carrying CYP2B6 single nucleotide polymorphisms, known to play a role in the metabolism of EFV. None of the children had a CYP2B6 wildtype haplotype. We believe this is the first case of cerebellar dysfunction associated with efavirenz use to be described in children.Case presentationFour black African children, between the ages of 4 and 8years presenting between 1 and 20months post-efavirenz initiation, are described. Cerebellar dysfunction, generalised seizures and absence seizures were the range of presenting abnormalities. Plasma efavirenz levels ranged from 20-60mg/L, 5–15 times the upper limit of the suggested reference range. All abnormal central nervous system manifestations abated after efavirenz discontinuation.ConclusionEfavirenz toxicity should always be considered in human immunodeficiency virus-infected children with unexplained central nervous system abnormalities. Our findings further our understanding of the impact of genetic variants on antiretroviral pharmacokinetics in children across various ethnic groups. Screening for potential EFV-toxicity based on the CYP2B6 c.516 SNP alone, may not be adequate.
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    Chronic otorrhoea: Spectrum of microorganisms and antibiotic sensitivity in a South African cohort
    (2013) Meyer, E; Whitelaw, A; Edkins, O; Fagan, J J
    BACKGROUND: Chronic otorrhoea is difficult to treat, with treatment in South Africa (SA) being protocol driven and generally initiated at the primary healthcare level. There is a lack of local studies that focus on the bacteriology and antimicrobial sensitivities of chronic otorrhoea, which underpins the management advice offered. AIMS: To determine the microbiological profile and antimicrobial susceptibility of patients with chronic otorrhoea and the validity of the Department of Health's (DoH) current guideline. METHODS: We conducted a prospective study at Groote Schuur Hospital from 2005 to 2009. We included patients with chronic otorrhoea classified as either otitis media or otitis externa, according to our definitions. Pus swabs were taken, from which microorganisms were cultured and tested for antimicrobial susceptibility. RESULTS: Of 79 patients with otorrhoea, 50 had otitis media, 21 had otitis externa and the condition was not determined in 8 patients. The most common organism isolated with otitis media was Proteus mirabilis (18/50; 36%) and with otitis externa, Pseudomonas aeruginosa (7/21; 33%). Otorrhoea had a different microbial spectrum compared with international reports, with methicillin-resistant Staphylococcus aureus infection in a single patient. The organisms isolated were susceptible mainly to fluoroquinolones (96%) and aminoglycosides (81%). CONCLUSION: Amoxicillin is a poor choice of antibiotic due to its low sensitivity, which calls into question the current DoH guideline for otorrhoea. Antimicrobial treatment protocols should be based on local data and be revisited from time to time. This study suggests that, should first-line treatment fail, an antibiotic with Gram-negative cover, e.g. a topical fluoroquinolone, should be considered.
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    Guideline for the management of acute asthma in adults: 2013 update
    (2013) Lalloo, U G; Ainslie, G M; Abdool-Gaffar, M S; Awotedu, A A; Feldman, C; Greenblatt, M; IRUSEN, E M; Mash, R; Naidoo, S S; O\'Brien, J; Otto, W; Richards, G A; Wong,, M L
    Acute asthma attacks (asthma exacerbations) are increasing episodes of shortness of breath, cough, wheezing or chest tightness associated with a decrease in airflow that can be quantified and monitored by measurement of lung function (peak expiratory flow (PEF) or forced expiratory volume in the 1st second) and requiring emergency room treatment or admission to hospital for acute asthma and/or systemic glucocorticosteroids for management. The goals of treatment are to relieve hypoxaemia and airflow obstruction as quickly as possible, restore lung function, and provide a suitable plan to avoid relapse. Severe exacerbations are potentially life-threatening and their treatment requires baseline assessment of severity, close monitoring, and frequent reassessment using objective measures of lung function (PEF) and oxygen saturation. Patients at high risk of asthma-related death require particular attention. First-line therapy consists of oxygen supplementation, repeated administration of inhaled short-acting bronchodilators (beta-2-agonists and ipratropium bromide), and early systemic glucocorticosteroids. Intravenous magnesium sulphate and aminophylline are second- and third-line treatment strategies, respectively, for poorly responding patients. Intensive care is indicated for severe asthma that is not responsive to first-line treatment. Antibiotics are only indicated when there are definite features of bacterial infection. Factors that precipitated the acute asthma episode should be identified and preventive measures implemented. Acute asthma is preventable with optimal control of chronic asthma.
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    National sentinel site surveillance for antimicrobial resistance in Klebsiella pneumoniae isolates in South Africa, 2010 - 2012
    (2014) Perovic, Olga; Singh-Moodley, Ashika; Dusé, Adriano; Bamford, Colleen; Elliott, G; Swe-Han, Khine Swe; Kularatne, Ranmini; Lowman, Warren; Whitelaw, Andrew; Nana, Trusha; Wadula, Jeanette; Lekalakala, Ruth; Saif, Adrienne; Fortuin-de Smit, Melony; Marais, Else
    ABSTRACT BACKROUND: The increasing rates of antimicrobial resistance observed in the nosocomial pathogen Klebsiella pneumoniae are of major public health concern worldwide. OBJECTIVES: To describe the antibiotic susceptibility profiles of K. pneumoniae isolates from bacteraemic patients submitted by sentinel laboratories in five regions of South Africa from mid-2010 to mid-2012. Molecular methods were used to detect the most commonly found extended-spectrum beta-lactamase (ESBL) and carbapenemase resistance genes. METHODS: Thirteen academic centres serving the public healthcare sector in Gauteng, KwaZulu-Natal, Free State, Limpopo and Western Cape provinces submitted K. pneumoniae isolates from patients with bloodstream infections. Vitek 2 and MicroScan instruments were used for organism identification and susceptibility testing. Multiplex polymerase chain reactions (PCRs) were used to detect blaCTX-M, blaSHV and blaTEM genes in a proportion of the ESBL isolates. All isolates exhibiting reduced susceptibility to carbapenems were PCR tested for blaKPC and blaNDM-1 resistance genes. RESULTS: Overall, 68.3% of the 2 774 isolates were ESBL-positive, showing resistance to cefotaxime, ceftazidime and cefepime. Furthermore, 46.5% of all isolates were resistant to ciprofloxacin and 33.1% to piperacillin-tazobactam. The major ESBL genes were abundantly present in the sample analysed. Most isolates (95.5%) were susceptible to the carbapenems tested, and no isolates were positive for blaKPC or blaNDM1 There was a trend towards a decrease in susceptibility to most antibiotics. CONCLUSION: The high proportion of ESBL-producing K. pneumoniae isolates observed, and the prevalence of ESBL genes, are of great concern. Our findings represent a baseline for further surveillance in SA, and can be used for policy and treatment decisions.
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    Prevention of diseases after menopause
    (2014) Lobo, R A; Davis, S R; de Villiers, T J; Gompel, A; Henderson, V W; Hodis, H N; Lumsden, M A; Mack, W J; Shapiro, S; Baber, R J
    AbstractWomen may expect to spend more than a third of their lives after menopause. Beginning in the sixth decade, many chronic diseases will begin to emerge, which will affect both the quality and quantity of a woman's life. Thus, the onset of menopause heralds an opportunity for prevention strategies to improve the quality of life and enhance longevity. Obesity, metabolic syndrome and diabetes, cardiovascular disease, osteoporosis and osteoarthritis, cognitive decline, dementia and depression, and cancer are the major diseases of concern. Prevention strategies at menopause have to begin with screening and careful assessment for risk factors, which should also include molecular and genetic diagnostics, as these become available. Identification of certain risks will then allow directed therapy. Evidence-based prevention for the diseases noted above include lifestyle management, cessation of smoking, curtailing excessive alcohol consumption, a healthy diet and moderate exercise, as well as mentally stimula...
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    South African tobacco smoking cessation clinical practice guideline
    (2013) van Zyl-Smit, Richard N; Allwood, Brian; Stickells, David; Symons, Gregory; Abdool-Gaffar, Sabs; Murphy, Kathy; Lalloo, Umesh; Vanker, Aneesa; Sabur, Natasha F; Richards, Guy
    Tobacco smoking (i.e. cigarettes, rolled tobacco, pipes, etc.) is associated with significant health risks, reduced life expectancy and negative personal and societal economic impact. Smokers have an increased risk of cancer (i.e. lung, throat, bladder), chronic obstructive pulmonary disease (COPD), tuberculosis and cardiovascular disease (i.e. stroke, heart attack). Smoking affects unborn babies, children and others exposed to second hand smoke. Stopping or 'quitting' is not easy. Nicotine is highly addictive and smoking is frequently associated with social activities (e.g. drinking, eating) or psychological factors (e.g. work pressure, concerns about body weight, anxiety or depressed mood). The benefits of quitting, however, are almost immediate, with a rapid lowering of blood pressure and heart rate, improved taste and smell, and a longer-term reduction in risk of cancer, heart attack and COPD. Successful quitting requires attention to both the factors surrounding why an individual smokes (e.g. stress, depression, habit, etc.) and the symptoms associated with nicotine withdrawal. Many smokers are not ready or willing to quit and require frequent motivational input outlining the benefits that would accrue. In addition to an evaluation of nicotine dependence, co-existent medical or psychiatric conditions and barriers to quitting should be identified. A tailored approach encompassing psychological and social support, in addition to appropriate medication to reduce nicotine withdrawal, is likely to provide the best chance of success. Relapse is not uncommon and reasons for failure should be addressed in a positive manner and further attempts initiated when the individual is ready. Key steps in smoking cessation include: (i) identifying all smokers, alerting them to the harms of smoking and benefits of quitting; (ii) assessing readiness to initiate an attempt to quit; (iii) assessing the physical and psychological dependence to nicotine and smoking; (iv) determining the best combination of counselling/support and pharmacological therapy; (v) setting a quit date and provide suitable resources and support; (vi) frequent follow-up as often as possible via text/telephone or in person; (vii) monitoring for side-effects, relapse and on-going cessation; and (viii) if relapse occurs, providing the necessary support and encourage a further attempt when appropriate.
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    Systematic review of the evidence for rational dosing of colistin
    (2014) Visser Kift, E; Maaartens, G; Bamford, C
    BACKGROUND: There is an alarming global increase in the incidence of nosocomial infections with multidrug-resistant Gram-negative bacteria, which are often only susceptible to colistin. Colistin was developed prior to current methods of establishing dosing using pharmacokinetic-pharmacodynamic relationships. Dosing regimens differ in package inserts from different manufacturers and in different guidelines. It is imperative to avoid under-dosing with colistin in order to limit the development of resistance, as it is the last line of defence. METHODS: We conducted a systematic review of the literature to develop guidelines for rational dosing of intravenous colistin, with a particular focus on critically ill patients. RESULTS: Colistin is administered as the inactive pro-drug colistimethate sodium. Colistin demonstrates concentration-dependent bacterial killing, suggesting that higher doses should be administered less frequently to achieve higher peak concentrations. Dose-related nephrotoxicity occurs, making it impossible to safely achieve concentrations that prevent the selection of resistant mutants or the effective eradication of bacteria with higher minimum inhibitory concentrations. Theoretically, combination therapy should be used to reduce the risk of selection of resistant bacteria. In critically ill patients, a loading dose should be given to rapidly achieve therapeutic concentrations, followed by maintenance doses of 4.5 MU 12-hourly. Maintenance dose adjustment is necessary with renal impairment. CONCLUSION: Easier access to colistin is needed in South Africa, where it is not a registered medicine. Further research is needed to better characterise colistin's pharmacokinetic-pharmacodynamic relationships in humans and to establish whether combinations of colistin with other antimicrobials result in improved clinical outcomes or a reduction in selection of resistant bacteria.