These results support the reliability of basophil activation tests using either CD63 or CD203c as cellular tests in the in vitro diagnosis of patients with bee or wasp venom allergy with a slightly higher sensitivity for the CD203c protocol.

A markedly acid surface reaction is a characteristic attribute of the healthy human skin. The physiologic occurrence of strictly localized zones where acidity is diminished has been the subject of previous reports 1,2; they deal primarily with differences among the skin pH patterns of children, adolescents, and adults.Little is known about the skin pH of infants during the first month after birth. The only pertinent investigation known to us is that of Taddei.3 His findings uniformly demonstrate that the skin pH is maintained in the neighborhood of 6.5 from birth through the 20th day. The presence of such uniform and relatively elevated values would tend to indicate that the mechanism responsible for the physiologic acidification of the skin surface has not yet developed in these young infants.Our own studies do not confirm Taddei's findings. It is the purpose of this communication to report the results of skin pH determinations obtained from a series of infants from birth through the first month and to discuss the physiologic implications. Subjects Tested and Methods of ExaminationThe report is based on 945 individual pH de¬ terminations carried out in 222 subjects ranging in age from 1 hour to 30 days. Serial determina¬ tions were done on 27 infants; all other subjects were tested at one age only. The whole series includes 109 boys and 113 girls; of these, 64 were Caucasians; 60, Negroes, and 98, Puerto Ricans. They were selected from hospital nurseries, wards, and a few from private practice. They were healthy full-term babies of not less than 5 lb.(2470 gm.), afebrile and without noticeable dis¬ ease. Some of the older infants were convalescing from illness or surgery. The presence of skin eruptions excluded selection for testing. Skin pH determinations were carried out ac¬ cording to the colorimetrie method of Bernstein and Herrmann,4 with slight modifications as described and evaluated in earlier reports.1,2 A solu¬ tion * prepared according to the originally recom¬ mended formula served as indicator throughout. In addition to the requirements applying to colori¬ metrie skin testing in general, some special pre¬ cautions were felt to be in order prior to testing newborns. The use of soaps, detergents, or other chemicals was strictly avoided. Only plain water was used for routine cleansing of the skin after birth. Application of baby toiletries prior to and during the test period was prohibited.As in earlier investigations, the results were checked potentiometrically, at times, by means of the Beckmann pH meter, in conjunction with the special glass electrode devised for the examination of minute traces of aqueous material on small surface areas.6With a few exceptions, the skin pH was tested in each infant and at each session at three sites :(1) on the shoulder where the deltoid covers the acromion ; (2) on the armpit, in an area roughly corresponding to the axillary vault, and (3) on the abdomen at a site at least 2 in. lateral to and either just proximal to or just distal to the navel. Separate testing of ...

Non-invasive investigations of skin morphology and function are standard tools to study the pathophysiology of several cutaneous disorders, yet they have not been used in population-based epidemiological studies. Here we examined skin surface pH, stratum corneum hydration, trans-epidermal water loss (TEWL) and skin roughness by profilometry in a study population comprising 377 primary school children (8-9 years old) as part of a multicentre survey on risk factors for allergic diseases in school children. Skin surface pH showed significant higher values (p=0.029) in the group with atopic eczema (n=45) compared with the group without atopic eczema; all other parameters did not differ significantly between children with and without atopic eczema. With increasing skin dryness there was a significant increase in pH values (p=0.004). Stratum corneum hydration showed a significant decrease with increasing dryness (p<0.001). Measurement of skin roughness also revealed a significant linear relationship with skin dryness (p=0.02). It is concluded that measurement of skin surface pH, corneometry and profilometry are useful non-invasive techniques to objectively assess skin dryness in epidemiological studies regarding atopic skin disease.

1. Rabbit ears were single-pass perfused with a cell-free medium. Arterial pressure, oxygen consumption, and lactate production increased with flow rate. 2. Methyl salicylate was hydrolysed with an apparent Vmax of 1.5 nmol/min per cm2 surface area, a rate about 25 times greater than after arterial administration. 3. Estimation of the Km was not possible, due to oedema developing at arterial concentrations greater than 100 microM methyl salicylate. 4. The model appears suitable to compare absorption, as well as metabolic rates, of xenobiotics in rabbit skin.

Histamine is known to be a classical inducer of pruritus. In atopic eczema, itch is a prominent feature (regarded by some even as a 'primary lesion'!). One of the most potent chemical mediators of itch is histamine. Histamine, together with other mediators may play a role in the pathophysiology of atopic eczema: the increased release of histamine from basophil leucocytes of atopic patients has been described, as well as elevated histamine levels in plasma and skin during acute exacerbations of eczematous lesions. Therefore, application of H1 antagonists seems to be a rational regime in the symptomatic treatment of atopic eczema. Nevertheless, some controversy exists regarding the clinical efficacy of orally applied H1 antagonists in this disease, especially with regard to the newer non-sedating compounds such as terfenadine, astemizole, loratadine and cetirizine. Review of the literature shows that there are studies demonstrating a clear-cut antipruritic effect of non-sedating H1 antagonists. Thus the sedative action does not seem necessarily to be connected with therapeutic efficacy in treating itch in atopic eczema. Newer studies show that cetirizine exerts an additional inhibitory effect on eosinophils. This may broaden the therapeutic spectrum of this H1 antagonist in diseases with eosinophil involvement.