Adrenergic mechanisms and immediate-type allergy

[Severe anaphylactic shock with heart arrest caused by coffee and gum arabic, potentiated by beta-blocking eyedrops]

The case of a male patient who experienced four allergic accidents after drinking coffee is reported. Two serious anaphylactic reactions with cardiac arrest occurred after a continuous treatment with beta-blocking eye drops (timolol) was prescribed. Dual sensitivation to coffee and to the gum arabic coating roasted coffee beans was demonstrated by skin prick tests and by human basophil degranulation tests. Occupational allergy to green coffee has been widely described, but food sensitization to these two allergens has not yet been reported. This case also draws attention to the risk, inherent in beta-blockers, of immuno-allergic reactions. These drugs produce a loss of compensatory cardiovascular mechanisms and make those who take them resistant to the conventional treatment of anaphylactic shocks, which explains the serious accidents that occurred in this patient. The authors stress the usefulness of a thorough investigation for food allergy to a rare allergen in patients with idiopathic anaphylaxis.

The effect of sodium cromoglycate, beclomethasone diproprionate and salbutamol on the ventilatory response to cotton dust in mill workers

A double-blind placebo controlled study of sodium cromoglycate, beclomethasone dipropionate and salbutamol by inhalation was designed to test their effect on respiratory symptoms and changes in ventilatory capacity in cotton mill workers. All three drugs showed some beneficial effect. Salbutamol was the most effective drug studied, in all groups of workers. Beclomethasone dipropionate was also significantly effective particularly in workers with byssinosis or exertional dyspnoea. Sodium cromoglycate was the least effective of the three. Possible mechanisms of action of these drugs are described.