Associations between asthma and bronchial hyper-responsiveness with allergy and atopy phenotypes in urban black South African teenagers.

OBJECTIVES: To determine asthma and allergy phenotypes in unselected urban black teenagers and to associate bronchial hyper-responsiveness (BHR) with asthma, other atopic diseases and allergen sensitisation. METHODS: This was a cross-sectional study of 211 urban high-school black children of Xhosa ethnicity. Modified ISAAC questionnaires regarding asthma, eczema and rhinitis were administered. BHR was assessed by methacholine challenge using hand-held nebulisers. Skinprick tests (SPTs) were performed for 8 aeroallergens and 4 food allergens. RESULTS: Asthma was reported in 9%, and 16 % demonstrated BHR. Rhinitis was reported in 48% and eczema in 19%. Asthma was strongly associated with BHR. Asthma was associated with eczema whereas BHR was associated with rhinitis. SPTs were positive in 34% of subjects, aeroallergens in 32%, and food allergens in 5%. The most common sensitivities were to house dust mites (HDM) and German cockroach. BHR was associated with sensitivity to any aeroallergen, cat, HDM, cockroach and bermuda grass. The number of positive SPTs was associated with asthma and BHR. With each level of SPT positivity, there was 40% increased prevalence of asthma and 70% increased prevalence of BHR. The rate of allergen sensitisation in subjects with BHR (72%) was much higher than those without BHR (28%); house dust mite sensitivity was 69% in subjects with BHR and 18% in those without. CONCLUSIONS: These are the highest rates of allergen sensitisation in subjects with BHR documented in an African setting and the widest difference in sensitisation rates between subjects with and without BHR.

Guideline for the management of chronic asthma in children--2009 update.

OBJECTIVE: To revise the guideline for the diagnosis and management of chronic asthma in children in view of the following considerations: the existing South African Childhood Asthma Working Group (SACAWG) guideline was produced 10 years ago; diagnosis of asthma in young children remains a challenge; evidence-based treatment is the new paradigm; new treatment approaches to achieving and maintaining control; therapeutic roles of several medications have evolved; more studies and data on treatment in young children; new medications and formulations; a change of emphasis in assessing asthma control to guide treatment changes. The main aim of the guideline is to promote a better standard of treatment based on understanding of the pathophysiology and pharmacotherapy of asthma, and encouraging uniformity in asthma management. EVIDENCE: A detailed literature review by a working group of clinicians from relevant disciplines. The strategies recommended are classified according to the evidence category in Appendix B, and denoted as Evidence A, B, C and D. RECOMMENDATIONS: These include an appropriate diagnostic approach, environmental control measures, treatment options, definition of asthma control, and strategies to achieve control. ENDORSEMENT: The guideline document was endorsed by the South African Thoracic Society (SATS), the National Asthma Education Programme (NAEP), the South African Paediatric Association (SAPA) and the South African Academy of Family Practice.

Total IgE in urban Black South African teenagers: the influence of atopy and helminth infection.

Total IgE levels are usually elevated in allergic diseases, being highest in atopic eczema, followed by atopic asthma and allergic rhinitis. Genetic factors are believed to play a role in total IgE levels, with higher levels seen in Black African subjects. Total IgE is also raised in parasite infection. Thus, the higher total IgE levels in Black Africans could be because of environmental rather than genetic factors. Few studies have investigated the usefulness of total IgE levels in the evaluation of atopy in Black Africans. The objective of this study was to determine the total IgE levels in unselected urban Black African high school children and to correlate this with atopy and ascaris sensitization. Atopic status was assessed by means of specific allergen sensitization (skin prick tests to eight inhalant and four food allergens), self-reported asthma and bronchial hyper-responsiveness measured by methacholine challenge. Ascaris sensitization was assessed by means of ascaris IgE measured by CAP-RAST. Total IgE levels were markedly skewed toward the left and were not distributed in a Gaussian or a log-normal distribution. Skin prick tests were positive for aeroallergens in 32.3% of subjects. Thirty four percent had elevated ascaris IgE. Total IgE was higher in atopic vs. non-atopic subjects and correlated with the number of positive skin prick tests, self-reported asthma and bronchial hyper-responsiveness. Subjects without allergy (or) atopy had a median total IgE of 80-90 kU/I. In addition total IgE correlated with ascaris IgE. Subjects with no ascaris sensitization had median total IgE of 77.1 kU/l. Subjects with neither atopy/asthma nor ascaris sensitisation had a median total IgE of 69.9 kU/I, similar to the levels seen in people of other genetic origins. This study suggests that helminthic infection rather than genetic differences, may be the major determining factor of IgE levels in certain populations.

Guideline for the management of chronic asthma in children--2000 update. Allergy Society of South Africa Working Group.

OBJECTIVE: To increase awareness of asthma and diagnose asthma early in children. To make recommendations regarding management of chronic childhood asthma in a country with diverse cultural, socio-economic and educational characteristics. The guideline should be used by health professionals involved in the treatment of asthma at all levels of care. OPTIONS: Various management options were considered. Ideal treatment includes use of the new generation inhaled corticosteroids (fluticasone, budesonide), housedust mite intervention for asthma control using impermeable covers for pillows and mattresses, and if needed use of inhaled long-acting beta 2 agonists (LABAs) and leukotriene receptor antagonists (LRAs). Alternative therapeutic approaches for situations where resources are limited include simple housedust mite control measures (e.g. airing mattresses and bedding), avoidance of exposure to passive smoking, use of lower doses of beclomethasone than recommended by other guideline documents and/or sustained-release (SR) theophylline as preventer treatment and use of plastic bottles as cheap spacer devices. OUTCOMES: The main potential outcomes considered were: to reduce morbidity and mortality by correct diagnosis of asthma, to achieve the best quality of life for the child with asthma, to minimise side-effects from medication and to prevent development of permanently abnormal lung function. EVIDENCE: Current international guideline documents for diagnosis and management of childhood asthma were evaluated. Clinical studies before 1998 pertaining to the various aspects of management of childhood asthma were reviewed, including controlled studies on the use of inhaled corticosteroids in children with asthma, randomised controlled trials on the use of LRAs and two studies evaluating the efficacy of LABAs. Current data on the anti-inflammatory effects of SR theophylline were also reviewed as well as a randomised controlled trial on the benefits of SR theophylline as adjunct treatment in childhood asthma. The benefit of simple spacer devices, based on well-conducted local studies (published in an international peer-reviewed journal) was also considered. VALUES: The South African Childhood Asthma Working Group (SACAWG) committee members, appointed by the Allergy Society of South Africa (ALLSA), were selected to represent the interests of health professionals involved in the care of childhood asthma and to co-opt other colleagues with expertise relevant to the guideline. The committee was divided into six task groups headed by a chairperson--each task group had to review critically the previous SACAWG guideline (for deficiencies and obstacles to implementation), review current trends in asthma management (evidence-based where available) and submit proposals and recommendations to their respective chairperson. The chairperson then compiled a report for discussion by the SACAWG executive committee. The executive group convened a meeting to discuss the recommendations and obtain consensus. An editorial board was appointed to compile the final report. Cultural factors, patient preferences, cost, availability and education were considered important. BENEFITS, HARMS AND COSTS: Proper treatment should enable most children with asthma to lead normal or near-normal lives. The guideline could be implementable at all levels of care. The risk of systemic effects due to inhaled corticosteroids should be minimised in children with mild to moderate persistent asthma (risk of systemic effects is more likely at daily beclomethasone doses exceeding 400 micrograms or the equivalent dose of other inhaled corticosteroids). Promotion of simple environmental control measures and use of inhaled beclomethasone and/or SR theophylline should make treatment more widely available and more affordable and improve adherence to treatment. Alternative cheap plastic bottle spacer devices will increase availability and assist with overcoming the problem of incorrect inha

Cholestatic disorders of infancy--aetiology and outcome.

The relative frequency of causes of cholestatic disorders of infancy in a developing area was established in a prospective study. During a 10-year period, 145 infants with conjugated hyperbilirubinaemia were investigated. Intrahepatic disorders accounted for 68 per cent with no identifiable cause (idiopathic hepatitis) in the majority. Syphilis, urinary tract infection and septicaemia together made up 30 per cent of intrahepatic causes with metabolic disorders accounting for 12 per cent. Outcome in those with idiopathic hepatitis, and those treated for syphilis and UTI was relatively good. Complete recovery from syphilitic hepatitis on average took 11 months. Extrahepatic disorders occurred in 32 per cent and were almost entirely due to biliary atresia. Results of hepatic portoenterostomy for biliary atresia were poor because of late referral in many instances. Compared to developed countries, infantile cholestasis in developing areas is more commonly associated with treatable bacterial infection. Referring agencies should be aware of this fact and the need for early referral of cases with possible biliary atresia.

Effect of loperamide on stool output and duration of acute infectious diarrhea in infants.

This study was designed to assess the effect of loperamide, given to infants in higher than recommended doses, on the severity and duration of acute diarrhea. Thirty infants with acute diarrhea and dehydration were given loperamide (0.8 mg/kg/day), in addition to standard fluid therapy, for 48 hours after admission to the hospital. The stool output in grams per kilograms of body weight per day and the duration of diarrhea in these infants were compared with those in 30 matched control infants receiving only standard fluid therapy. Two infants given loperamide had to be withdrawn from the trial because ileus developed in one and the other had persistent severe vomiting. In four other infants receiving loperamide, drowsiness developed but resolved rapidly on discontinuation of the drug. Infants receiving loperamide had a shorter duration of diarrhea (median 2.5 vs 6.0 days) and lower daily stool output than the control subjects had. The study confirmed the efficacy of loperamide in reducing the duration and severity of diarrhea but raised doubts regarding its safety in the treatment of young infants.

Anti-Staphylococcus aureus-specific IgE in atopic dermatitis.

Serum samples from 60 adults and 64 children with atopic dermatitis were tested for antistaphylococcal IgE antibodies with RAST discs coupled to cellular proteins from Wood 46 strain S. aureus. Anti-S. aureus IgE antibodies were detected in 19 (29.6%) of the children and 14 (23.3%) of the adult patients. Anti-S. aureus IgE-positive adults had more severe and prolonged disease than those who were negative. Two groups of children comprising 10 who were anti-S. aureus IgE positive and 10 who were negative were compared. Children with anti-S. aureus IgE antibodies had more severe and more extensive disease (p less than 0.05), a greater prevalence of cutaneous S. aureus infections (p less than 0.05), higher mean total serum IgE level (p less than 0.05), a greater prevalence of specific IgE responses to food allergens (p less than 0.05), and a higher percentage of helper T cells (p less than 0.05) than children who were negative for these antibodies.