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Notes: Summary Background  Atopic dermatitis is a common disease that appears to be increasing in frequency during recent decades. Most of the studies are based on the Western population, and there are few data in the Asian population.Objectives  To determine the prevalence and descriptive epidemiology of atopic dermatitis among school children in the general community in Singapore.Methods  This is a questionnaire study of 12 323 students done over a 1-year period, comprising 7 year olds (4605), 12 year olds (3940) and 16 year olds (3778) from 19 primary and 17 secondary schools randomly selected in Singapore. All children had a complete cutaneous examination. The diagnosis of atopic dermatitis was based on the U.K. Working Party diagnostic criteria. The questionnaire was translated into Chinese and both the English and Chinese versions were issued simultaneously to the students.Results  The 1-year period prevalence of atopic dermatitis was 20·8%. Atopic dermatitis was present in 22·7% of 7 year olds, 17·9% of 12 year olds and 21·5% of 16 year olds. The overall sex ratio was equal. There were slightly more boys with atopic dermatitis among the younger children (6 and 12 year olds, 1·18 : 1 and 1·19 : 1, respectively) but more girls were affected (1·57 : 1) among the 16 year olds. Atopic dermatitis was more common among the Chinese (21·6%) and Malays (19·8%) compared with the Indians (16%) and other races (14%). The onset of the disease occurred before the age of 10 years in 49·5% of the 16 year olds. ‘Pure’ atopic dermatitis without concomitant respiratory allergies was noted in 788 respondents (30·7%); 1775 (69·3%) suffered from a ‘mixed’ type, with 34·3% having allergic rhinitis, 9·5% having asthma and 25·5% having both asthma and allergic rhinitis. More boys had atopic dermatitis and concomitant respiratory allergies whereas more girls were affected with ‘pure’ atopic dermatitis alone (1·4 : 1). At least one first-degree family member with atopy was noted in 1435 children (56%): atopic dermatitis (70%), asthma (62%) and allergic rhinitis (68%). Among siblings with one parent with atopic dermatitis, 37% had either a father or a mother with atopic dermatitis. Common aggravating factors reported included exercise, heat and sweating, grass intolerance, thick clothing and stress. Pityriasis alba was noted in 25% of the study population, keratosis pilaris in 13% and ichthyosis vulgaris in 8%. Most respondents had mild to moderate atopic dermatitis that could be controlled with a fairly simple regimen of moisturizers, topical steroids, antihistamines and antibiotics.Conclusions  The high prevalence of atopic dermatitis in Singapore is similar to that observed in developed countries, suggesting that environmental factors may be important in determining the expression of the disease.

Notes: : The efficacy of topical aluminium chloride hexahydrate 20% W/W ethanol (ACH) in the treatment symptomatic palmar hyperhidrosis was studied in 12 patients. A half-sided control single blind (assessor blind) study was done. Patients applied ACH on one palm daily for 4 weeks. The response to treatment was measured objectively with an evaporimeter. There was significant fall of skin water vapor loss (SVL) on treated palms compared with untreated palms. The basal mean SVL of treated palms and untreated palms were 79·9 and 77·9 g water/m2/h, respectively (n.s.). The mean SVLs of treated vs. untreated palms at week 7, 2, 3, and 4 were 66·4 vs. 79·7 (p 〈 0·05), 56·6 vs. 72·2 (p 〈 0·001), 58·2 vs. 72·5 (p = 0·1), and 51·4 vs. 72·7 (p 〈 0·001) g water/m2/h, respectively. The mean SVL of treated palms returned near basal rate within 1 week of stopping treatment. Four patients developed skin irritation from ACH; in three this disappeared after 1 week and they were able to continue with treatment; one withdrew from the study because of the severe irritation. All patients reported that the ACH reduced palmar sweating within 48 hours of application; its effect disappeared within 48 hours after stopping treatment. ACH appeared to be useful in rapid control of palmar hyperhydrosis.

Notes: Abstract: A retrospective epidemiologic study of 110 patients with chronic paronychia (CP) showed a female-male ratio of 2·3:1, whereas the ratio of patients attending the same clinic was 1·1:1 (p 〈 0·001). The peak age range of patients with CP (40–49 years) generally was greater than that of the general dermatologic patients (20–29 years). Seventy-seven percent of the patients with CP were “manual workers,” of which 48% were homemakers. Chronic paronychia was more common on the right fingers than the left fingers. The most commonly affected fingers were the right thumb (62%), followed by the right middle finger (52%), left thumb (57·6%), and left middle finger (51·5%). Mechanical trauma appears to be an important predisposing factor in CP. Sixty-two percent of 68 patients who had nail fold smears had positive findings for budding yeast cells, suggestive of candidal infection. All of the six patients for whom nail fold bacterial cultures were performed had positive results for enteric flora.

Notes: : Of patients patch tested at a contact dermatitis clinic between 1985 and 1986, 22.5% (379/1685) had medicament sensitivity. The prevalence in men was 22.8% (193/847) and in women, 22.1% (186/838) (difference not significant). The rate appears to increase with age, 17.9% (216/1205) for patients less than 40 years old and 34.0% (163/480) for patients over 39 years old (difference, p 〈 0.001). The differences in prevalence between Chinese (22.8%), Malay (21.3%), Indians (20.4%), and others (33.3%) were not statistically significant. Common sensitizers included neomycin (7.8%), proflavine (7.1%), clioquinol (4.3%), colophony (3.3%), and wool alcohol (2.7%). Proflavine sensitivity was significantly more common in men (9.9%) than women (4.2%) (p 〈 0.001). Most dermatitis occurs on the limbs (upper limbs, 44.3%; lower limbs, 43.0%). Facial dermatitis was more common in women (37.4%) than men (19.2%) (difference not significant).

Notes: : The prevalence of contact allergy in 2471 patients patch tested in Singapore was 49.2% (571/1160) in women and 49.8% (653/1311) in men (sex difference not significant). The rate appeared to increase with age (43.7% in those 〈20 years, 50.6% between 20 and 49 years, and 63.1% in those 〉49 years). There was no significant difference in the prevalence of contact allergy among the major races (Chinese, Malay, and Indian) of Singapore. Contact allergies in 16.8% (96/571) of women and 38.9% (254/653) of men (p 〈 0.001) were occupational. Nickel, fragrance mix, proflavine, and chromate were common sensitizers. The male:female prevalence of nickel allergy was 1:2 (sex difference p 〈 0.001) and for chromate was 7:1 (sex difference p 〈 0.001). Chromate sensitivity was occupational in 87.7% (121/138) of men and 47.1% (8/17) of women (sex difference p 〈 0.001). Proflavine, neomycin, and clioquinol were the more common medicament sensitizers.

Notes: : Proflavine lotion is a commonly used topical antiseptic in the tropics, hut its sensitizing potential was never emphasized and many who developed allergic contact dermatitis were never aware of it. In a study of 45 patients, most presented with acute or subacute dermatitis which started on the arms and legs. Concomitant cutaneous sensitivity to other medicaments, and lanolin occurred in 66% of the patients.

Notes: This study attempts to demonstrate the existence of allergic contact dermatitis from grass, and to develop a patch test series to screen patients with grass intolerance. 6 common grass species from lawns and military training areas were collected. Solvent extracts of polar. non-polar and volatile fractions were prepared and used for patch testing in 20 control subjects and 46 patients with a history of grass intolerance. The 20 control had negative responses to patch testing. 5 out of 46 patients had positive patch tests to Axonopus compressus (carpet grass). Ischaenmum muticum (sea-shore centipede grass). Imperata evlindrica (lalang). Panicum maximum (Guinea grass) and Pennisetum purpureum (elephant grass). Reactions to the non-polar fraction for all 5 species were noted. This study demonstrates the existence of allergic contact dermatitis from various common species of grass. In our series, this is seen in 11% of those with a history of grass intolerance.

Notes: Worldwide, there are 3 major standard series of patch tests, the European, North American and Japanese, together presenting 32 allergens, the differences between them being the result of regional variation in allergen distribution as well as differences in dermatological opinion. We propose a “minimal” international standard series of 20 allergens, together with an “extended” international standard series of 14 allergens.