Temporal changes in sebum excretion and propionibacterial colonization in preadolescent children with and without acne.
ABSTRACT It is generally accepted that the onset of sebum secretion occurs before puberty in boys and girls as a result of increasing androgen output during the adrenarche. Propionibacteria are part of the commensal skin flora and, in adults, are found in highest numbers in sebum-rich areas of skin such as the face and upper trunk. Previous studies investigating the association between sebum output and propionibacterial population densities have been cross-sectional and have been carried out mainly in adults.
The purpose of this study was to examine the association between the onset of sebum secretion and expansion of the propionibacterial flora in a population of early adolescent children aged between 5.5 and 12 years, and to evaluate the temporal relation between the two factors longitudinally. In addition, the study aimed to evaluate the change with age in sebaceous gland activity and propionibacterial colonization on the skin and in the nares between children who developed acne and those who did not.
Biannual examinations of volunteers included age, pubertal (Tanner) stage, weight and height, lesion counting on the face, propionibacterial colonization on the skin surface and in the nares and sebum secretion. A longitudinal analysis based on all observations of each subject throughout the study was applied to examine the change of sebaceous gland activity and propionibacterial colonization with age and pubertal stage. A generalized estimating equation was used with a 0.05 level of significance.
The commencement of sebum production was asynchronous, with only a small number of follicles initially starting to secrete sebum onto the skin surface. The number of secreting follicles and the area of sebum increased with age and pubertal stage (P < 0.0001, P < 0.05, respectively). Numbers of propionibacteria on the skin tended to increase after the age of 9 years, but not significantly so. In contrast, numbers of propionibacteria in the nares increased significantly with age (P < 0.0001) but not with pubertal maturation. Children who developed acne had higher sebum output and propionibacterial densities with increasing age than children who did not develop acne. This effect was significant for the increase of total sebum area with age in pubertal children (P = 0.0023), the increase in number of secreting follicles with age (P = 0.020) in prepubertal children, and the increase in propionibacteria densities in the nares with age (P = 0.0005) in pubertal children. Sebaceous gland activity and propionibacterial numbers on the skin surface remained unchanged with increasing age in children who did not develop acne. Propionibacterial population densities in the nares increased with age regardless of the development of acne.
Onset of sebum secretion and consequently expansion of the propionibacterial skin flora occur earlier in children who develop acne than in children of the same age and pubertal status who do not develop acne. These observations suggest that postponing the onset of sebum production or the expansion of the propionibacterial skin flora until after puberty may represent ways of preventing the disease or minimizing its severity. Determinants of propionibacterial colonization on the skin and in the nares may be different.
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Article: Acne: inflammation.[show abstract] [hide abstract]
ABSTRACT: The inflammatory stage of acne vulgaris is usually of greatest concern to the patient. A number of morphologically different inflammatory lesions may form that can be painful and unsightly. In 30% of patients, such lesions lead to scarring(1). Inflammatory acne and acne scarring can have significant psychological effects on the patient, including depression, anxiety, and poor self-image(2). Although inflammatory acne has been well characterized clinically, the mechanisms by which inflammatory lesions arise are still poorly understood. The human skin commensal bacterium, Propionibacterium acnes, has long been associated with inflammatory acne. This organism has been implicated over and above all of the other cutaneous microflora in contributing to the inflammatory response characteristic of acne. However, its precise role in the disease and its interaction with the human immune system remain to be elucidated.Clinics in Dermatology 01/2004; 22(5):380-4. · 2.34 Impact Factor
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ABSTRACT: In this study we investigated the activity of the vellus hair follicle in acne. Hair growth and sebum excretion in vellus hair follicles were measured on the forehead and back of men, and on the forehead, cheek, and back of women with acne. Hair growth was assessed by computerized image analysis (phototrichogram), and sebum excretion by computer analysis using Sebutape. In patients with acne, marked differences were revealed when results were compared with recent data from healthy persons. In particular, the mean growth rate of vellus hairs was higher, whereas the percentage of anagen hairs was lower, and the duration of the anagen phase shorter in patients with acne than in healthy individuals. Hair growth and sebum excretion depended significantly (P < 0.01) on the anatomical site (forehead 414 hairs/cm2, 0.053 mm/day, 34%; back 93 hairs/cm2, 0.16 mm/day, 21%). In addition, analysis of hair growth revealed significantly higher values in females than in males for (i) percentage of anagen hairs (P > 0.01), (ii) for vellus hair length (P < 0.05), and (iii) for the duration of the anagen phase (P < 0.01). The present study demonstrates that the activity of the vellus hair follicle is influenced by acne, and vice versa, and therefore its role in the aetiopathogenesis of acne should be reconsidered.British Journal of Dermatology 08/1993; 129(1):23-7. · 3.76 Impact Factor
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ABSTRACT: Fifty-two children, age 5-10, from acne-prone families, were studied for a period of 1 year to examine the interrelationship between sebum, acne, pubertal development, and urinary steroid excretion. In each of the subjects, 30 boys and 22 girls, the composition of forehead skin lipid was determined 4 times yearly by thin-layer chromatography, with measurement of triglycerides, diglycerides, free fatty acids, wax esters, squalene, cholesterol, and cholesterol esters. Twice yearly, examination was made of the presence or absence of acne, pubertal maturation and the 24-hour urinary excretion of testosterone as determined by radioimmunnoassay, and of total 17-ketosteroids, dehydroepiandrosterone, androsterone, and etiocholanolone, as determined by paper chromatography. The relative amount of sebaceous lipids was positively correlated with age of the subjects (wax esters p less than .001, squalene p less than .05), as was the triglyceride-diglyceride component (p less than .05). No significant correlation was seen with the fatty acids. Acne, primarily comedonal, occurred in 27/52 subjects (15 girls, 12 boys) and was associated with higher sebum values. One-half of the children with acne had no signs of pubertal development. A significantly positive correlation was observed between the relative amount of sebaceous lipid and the urinary excretion of 17-ketosteroids, androsterone, and etiocholanolone in both sexes, and of testosterone and dehydroepiandrosterone in boys. The development of acne in children is an early pubertal event, often evident before other signs of pubertal maturation, and it is associated with an increase in sebum and in the urinary excretion of androgenic steroids.Journal of Investigative Dermatology 12/1977; 69(5):485-9. · 6.19 Impact Factor