Alessandra Pagnoni

Determination of density of follicles on various regions of the face by cyanoacrylate biopsy: correlation with sebum output

The density of follicles on various regions of the human face has received scant attention. We used cyanoacrylate follicular biopsies to determine the number of follicles on the forehead, cheek, chin and nose of 12 healthy adult white women. Sebum output was assessed on the same regions by means of Sebutape®. The density of follicles and sebum output followed a centrolateral decreasing gradient. There was no correlation between these two parameters. These regional patterns are important for studies of the pathogenesis of common disorders of the face and their response to treatment.

Digital fluorescence photography can assess the suppressive effect of benzoyl peroxide on Propionibacterium acnes

BACKGROUND Porphyrins produced by Propionibacterium acnes exhibit an orange-red fluorescence under UVA light. The amount of fluorescence can be estimated by digital fluorescence photography. OBJECTIVE We thought that digital fluorescence photography would be a quicker and simpler method than bacteriologic culture to demonstrate depopulation of P acnes in sebaceous follicles. We used benzoyl peroxide to bring about rapid suppression of P acnes. METHODS Benzoyl peroxide 10% was applied twice daily for 7 days to the faces of 9 subjects. Five subjects were untreated controls. Digital fluorescence photographs of cheek and nose, and scrub samples for quantitative recovery of P acnes from the cheek were taken at baseline, day 3, day 7 (end of treatment), and day 16 (regression phase). RESULTS The effect of benzoyl peroxide against P acnes was clearly demonstrated both by culture and by fluorescence photography after only 3 days. Image analysis of porphyrin fluorescence correlated well with the decrease in P acnes density from scrub cultures. No further decrease was observed at day 7 (end of therapy). Ten days later there was a return to baseline values, although in some subjects these remained lower. CONCLUSION Digital fluorescence photography is a reliable, fast, and easy screening technique to demonstrate the suppressive effect of topical antibacterial agents on P acnes.

Hypopigmented macules of photodamaged skin and their treatment with topical tretinoin.

Hypopigmented macules are frequently observed in the photodamaged skin of elderly people. We undertook to study and treat 2 types of hypomelanosis of photoaged skin. These lesions were: 1) idiopathic guttate hypomelanosis; and 2) macular hypomelanosis. Comparative studies included: 1) high-resolution photography using parallel polarized light, ultra-violet (UVA) and epiluminescence; 2) Silflo replicas for microtopography; and 3) suction device (Cutometer) for elasticity. Macular hypomelanosis was distinguishable from idiopathic guttate hypomelanosis because the macules were less white and less well demarcated. Glyphic markings were essentially absent in macular hypomelanosis, but variably effaced in idiopathic guttate hypomelanosis. Distensibility of the macules was characteristically low in proportion to the loss of glyphic markings. The chief histologic finding was the absence of melanin in basal keratinocytes. Macular hypomelanosis and idiopathic guttate hypomelanosis are probably related disorders along a spectrum of depigmentation. Treatment with tretinoin for 4 months restored the elasticity, the glyphic markings, with a partial restoration of pigmentation.

Lack of correlation of skin thickness with bone density in patients receiving chronic glucocorticoid

Abstract The objective was to test the hypothesis that there is a correlation between thinning of the skin and bone in patients on chronic oral glucocorticoids (GCs). This was a one-time cross-sectional analysis performed in an academic referral center. The study group consisted of 14 patients on GCs for a variety of disorders, including dermatomyositis, pemphigus vulgaris, pyoderma gangrenosum, and urticarial vasculitis. Skin thickness was compared with that of 24 sex- and age-matched controls. The main outcome measures were the bone density of the lumbar spine (L2–L4) and the skin thickness. The skin thickness (mm, mean ± SEM) in GC-treated ( n = 7) vs unmedicated age-matched Caucasian women ( n = 20) was 0.84 ± 0.04 vs 1.02 ± 0.04 ( t = 3.07, P < 0.01) in the upper arm, 1.13 ± 0.09 vs 1.49 ± 0.05 ( t = 3.65, P < 0.002) in the dorsal forearm, and 0.96 ± 0.07 vs 1.17 ± 0.02 ( t = 2.92, P < 0.01) in the ventral forearm. L2–L4 bone densities averaged 106 ± 2% in the GC-treated female patients relative to the age and sex-matched controls. There was no correlation between skin thickness and bone density. In GC-treated ( n = 4) vs unmedicated Caucasian men matched for age ( n = 4), skin thickness was 1.09 ± 0.4 vs 1.33 ± 0.05 ( t = 3.51, P < 0.02) in the upper arm, but was not significantly different at the two forearm sites. No correlation between skin thickness and bone density was observed. The level of type I procollagen mRNA in skin from three GC-treated patients was 45% of the value in three age-matched controls. In conclusion, GCs cause statistically significant thinning of skin independently of the effects on bone.