Nov 17, 1984 - after injection, with negative reaction to sodium chloride. The injection sites were ... two comments on sodium aurothiomalate that may not meet ...
1382
BRITISH MEDICAL JOURNAL
fore is our recent finding that pulmonary surfactant in the rat contains appreciable concentrations of vitamin E.5 This observation raises the possibility that pulmonary surfactant may exercise a dual role both in physical stabilisation of alveolar structure and also in the biochemical defence of lung tissue. If this hypothesis is correct then the premature infant may prove to be particularly vulnerable to lung injury from oxygen when vitamin E deficient, or when underdevelopment of the mechanisms of biosynthesis and secretion of surfactant prevents the disposition of the vitamin at this crucial site. Artificial surfactant for use in replacement treatment may be more effective if it contains this component. Further research using more appropriate animal models is clearly required. RICHARD C COTTRELL British Nutrition Foundation, London SWlX 8PS
KLARA MILLER British Industrial Biological Research Association, Carshalton, Surrey SM5 4DS 1 Ehrenkranz RA, Ablow RC, Warshaw JB. Effect of vitamin E on the development of oxygen-induced lung injury in neonates. Ann NY Acad Sci 1983; 393:452-66. 2 Ehrenkranz RA. Vitamin E and the neonate. Am J Dis Child 1980;134:1157-66. 3 Cottrell RC. Vitamin E. British Nutrition Foundation Bulletin 1984;9:143-54. 4 Wender DF, Thulin GE, Walker Smith GJ, Warshaw JB. Vitamin E affects lung biochemical and morphologic response to hyperoxia in the newborn rabbit. Pediatr Res 1981 ;15:262-8.
Sensitisation to human insulin SIR,-We cannot support the conclusion of Dr P Garcia-Ortega and others that any change from animal to human insulins in patients known to be allergic to insulin must be made with great caution (28 April, p 1271). As insulin allergy is rare, we have tried to get a wider picture by making available a standard intradermal test kit for investigating cases of alleged insulin allergy and measuring insulin specific IgG (IgGi) and IgE (IgEi) and maintaining a central register of such cases. This system has been in operation since the introduction of human monocomponent insulin. The skin test kit contains bovine, porcine, and human insulin (formulated as Actrapid) as well as the diluting media for Actrapid and Monotard. Both media contain 1 mg/ml of methylparahydroxybenzoate, and that for Monotard also contains zinc chloride. The IgGi determinations are performed by the method of Christiansen' and the IgEi determinations by the method of Falholt.2 So far 47 patients with suspected insulin allergy have been tested. Acute systemic reactions to insulin were observed in about one third of the patients; in all cases the symptoms occurred when the patient was treated with animal insulin. Allergic reactions have not been observed in patients treated exclusively with human monocomponent insulins (table). Results of skin tests No of cases
Positive reactions to all species Positive reactions to animal species, but weak or no reaction to human insulin Reaction against zinc only No reaction to any test substances
