Allergic sensitisation in South Africa: Exploring regional variation in sensitisation.

BACKGROUND: Allergy is a common health problem in South Africa (SA), and a rational approach to allergy testing is essential to ensure cost-effective as well as optimal patient diagnosis and management. OBJECTIVES: To review allergy testing data with respect to current national testing recommendations, and to explore the regional variations in sensitisation. METHODS: Retrospective data review on allergy testing from a private pathology provider in SA over a 2-year period. Data on skin-prick testing (SPT) and allergen-specific IgE testing originating from all the provinces of SA were collected and analysed with regards to allergen positivity rate and regional sensitisation patterns. RESULTS: Among the patients (N=45 0320) tested for a suspected inhalant allergy, 46% tested positive. Only 45% of these received additional testing for the nine recommended inhalant allergens included in the current national testing protocol. Among the patients (N=6 775) who received SPT for a suspected inhalant allergy, 59% yielded one or more positive results. The most frequent sensitising allergens were house dust mite (Dermatophagoides pteronyssinus) and grass pollen. The house dust mite, Blomia tropicalis, was a significant sensitiser in coastal regions. SPT identified two other important regional allergens which are not included in the current recommendations for inhalant allergen-specific IgE testing. CONCLUSIONS: The current diagnostic recommendations include allergens that demonstrate significant sensitisation in all regions of SA. Two additional allergens that show significant regional sensitisation in the South African population were identified. These findings may aid the recommendations for the most appropriate and cost-effective approach to allergy testing of symptomatic patients in SA.

Vitamin D deficiency and insufficiency in Africa and the Middle East, despite year-round sunny days.

Exposure to sunlight, specifically ultraviolet B (UVB), is essential for cutaneous vitamin D synthesis. Despite significant daily sunlight availability in Africa and the Middle East, persons living in these regions are frequently vitamin D insufficient or deficient. Vitamin D insufficiency (25-hydroxyvitamin D (25(OH)D) between 15 and 20 ng/mL (37.5-50 nmol/L)) has been described in various population groups, ranging from 5% to 80%. Risk factors include traditional dress and avoidance of sunlight exposure, and multiple dietary factors as a result of specific cultural beliefs. Vitamin D resistance due to calcium deficiency mechanisms has been described in similar population groups, which may lead to hypovitaminosis D. Should the new diseases related to hypovitaminosis D prove to be truly associated, Africa and the Middle East will become an epicentre for many of these conditions. Urgent attention will need to be paid to cultural dress and dietary behaviours if hypovitaminosis D is to be taken seriously. Should such factors not be correctable, new strategies for supplementation or food fortification will have to be devised.

Objective methods for evaluation of interferential therapy in the treatment of incontinence.

Electrotherapy is a treatment for various conditions, and can be difficult to quantify in effect. This paper examines the form known as interferential therapy, with particular application in the management of urinary incontinence. Objective validation of the treatment is described, which allows optimal positioning of the electrodes for a particular patient.