Clinical characteristics of black asthmatic children.

A prospective study of 455 black asthmatic children (277 boys) attending the Baragwanath Hospital asthma clinic was undertaken. A history was obtained by means of a standardised questionnaire and skin tests were performed. Cough was the commonest presenting symptom and upper respiratory tract infections, exercise and cold weather the commonest symptom precipitants. The relative incidences of the other precipitants reflected the environment of the study population. Associated atopic conditions were present in 75.5% of patients and a family background in 22.2%. Other respiratory diagnoses were commonly made, particularly tuberculosis, which was diagnosed in 7.4%. Fewer than one-third had no positive skin reaction. The commonest allergens were grasses, pollen and house-dust mites. The high proportion of house-dust mite sensitivity (44.2%) contradicts beliefs that they are rare at higher altitudes.