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Skin specimens of patients suffering from actinic comedones, young patients with acne vulgaris, and normal controls of the same age groups respectively were subjected to in vitro autoradiography. From the results it can be concluded, that a rise in the proliferational activity in the follicular infundibulum due to actinic stimuli is responsible for the development and growth of actinic comedones.
Solitary plaques developed on the sun-exposed and damaged skin of five elderly, fair-skinned individuals. The lesions, erythematous to bluish confluent nodules and plaques with a cribriform appearance and comedone-like structures, presented a distinctive histologic picture of dilated, keratin-filled follicles within a matrix of amorphous, damaged collagen. We believe these cases demonstrate a distinct entity within the realm of actinic dermatoses, for which the name "actinic comedonal plaque" seems appropriate.
Comedones were extracted from twenty subjects using topical 1% clindamycin phosphate and were assayed for free clindamycin. Positive specimens were obtained from sixteen subjects at 2 weeks and from eighteen at 4 weeks, with levels of 0.06 to 1.49 micrograms/mg. Mean content was 0.39 +/- 0.08 micrograms/mg and 0.6 +/- 0.11 micrograms/mg, respectively. These values closely match levels previously determined following treatment with clindamycin hydrochloride, which may explain how these two esters can be similarly effective therapeutically. Satisfactory cooperation by the participants was likely obtained because their clinical progress paralleled that reported in other studies. Comedonal material reported as negative could very well contain effective levels of clindamycin, since minimum inhibitory concentrations of that antibiotic for most strains of Propionibacterium acnes are far below those detectable by current bioassay methods.
We report a 49-year-old white woman having asymptomatic hyperkeratotic comedone-like lesions on her legs, arms and trunk. Her sister is similarly affected, but less severely. The clinical and histopathological features indicated a diagnosis of familial dyskeratotic comedones, a rare autosomal dominant condition.
The primary change found in cellular material expressed from open comedones of patients who had been treated with isotretinoin was disintegration of desmosomes. Consequently, there was lack of cohesion between cornified cells. A marked decrease in the quantity of sebaceous material and bacteria was also evident within the comedones.
The potential role of different species of comedonal bacteria as chemotactic stimuli in the inflammatory phase of acne vulgaris was investigated by comparing 12 strains of Staphylococcus epidermidis, 11 strains of Propionibacterium acnes, and 5 strains of P. granulosum for production of cytotaxin in vitro. Results indicated that not only were there marked differences in cytotaxin production between different strains of the same species grown under identical growth conditons, but there were often significant differences in cytotaxin activity of the same strain grown in different media. This finding is discussed in relation to development of inflammation in quiescent comedones in acne vulgaris.
The water soluble fraction of 713 open comedones, pooled from both the face and back of 47 subjects representing all grades of acne, were analyzed for total protein content, carbohydrate content, and for identification of specific proteins. In the water soluble fraction, the protein content represented 11.5%, and carbohydrate content 0.2% of the total comedonal crude weight. Esterase and hyaluronidase activity was demonstrated. Propionibacterium acnes antigenic material, serum albumin, and serum Zn alpha 2 glycoprotein, a minor serum constituent, were identified by immunodiffusion and immunoelectrophoresis.
The usefulness of topical vitamin A acid for senile comedones was reported by Kligman et al. in 1971 (1). It is, however, not available in Japan. We treated senile comedones with topical 5-fluorouracil ointment and found that it was very effective.
Three concentrations of tetradecane and liquid paraffin were applied daily for 4 weeks to the external ear skin of rabbits, and the average diameter of the follicular lesions was measured under the Leitz MZ surface microscope. These observations showed that the increase in the size of follicular lesions with tetradecane was dose-dependent and the maximum diameter was reached on the 14th day. Serial biopsies were also taken for routine histology, and undiluted tetradecane was shown to produce follicular hyperkeratosis, microcomedones, closed comedones and open comedones. A good correlation was obtained between the surface observations and the histological findings. The surface microscope provides a simple and convenient in vivo method for evaluating comedo formation.
Skin surface lipids and lipids from open and closed comedones in acne patients were analysed by thin layer chromatography. The results showed that these lipids were enriched in polar lipids, as compared with the skin surface lipids obtained from controls without acne. In both open and closed comedones, these polar lipids appeared to be derived mainly from the oxidation of squalene, which is in agreement with our previous in vitro results. We suggest that squalene oxidation is the link between comedogenesis and bacterial colonization, and based on this, we propose a hypothesis of the pathogenesis of acne.
Sebum excretion rate was measured by a photometric technique. We demonstrated a high correlation between sebum excretion rates on the left and right sides of the upper back and between back and forehead skin. Sebum excretion rate measurements overlying an open comedone (blackhead) were significantly lower than those obtained from normal skin. This observation demonstrates a functional obstruction to the outflow of sebum and would suggest that the lack of involvement of open comedones in inflammatory acne is not because of the maintenance of a free flow of sebum.
Two hundred and eighty-six patients over the age of 65 (age range 65-102, mean age 82 years), who were hospitalized in geriatric wards, were examined clinically for the presence of sebaceous gland hyperplasia and senile comedones. The degree of solar elastotic change present was scored on a visual analogue scale. The prevalence rate of sebaceous gland hyperplasia and of senile comedones was found to be 26% in each case. Approximately one third of patients had both lesions. Neither of these lesions was related to either the degree of solar elastotic change or the skin type with regard to tanning ability. It was concluded that chronic solar exposure was not a likely cause of these common conditions.
A 59-year-old woman with a single cuff-like plaque, consisting of multiple skin-coloured to bluish cysts and comedones on her right forearm is reported. The solitary lesion resembled, morphologically and histologically, the Favre-Racouchot syndrome. The above condition is another case of the previously described actinic comedonal plaque, which seems to be a rare entity within the spectrum of disease caused by actinic damage to the skin.
The effect of 1/10 minimal inhibitory concentrations (sub-MIC) of erythromycin (EM) on human neutrophil chemotactic factor production in comedonal bacteria, Propionibacterium acnes strains, Propionibacterium granulosum strains and coagulase-negative staphylococcus (CNS) strains was assayed using the Boyden chamber method. Sub-MIC of EM significantly suppressed neutrophil chemotactic factor production in all strains of P. acnes, P. granulosum and CNS. Our results suggest that sub-MIC of EM may have an anti-inflammatory action by reducing the inflammatory capacity of comedonal bacteria in inflammatory acne.
BACKGROUND: Acne patients who fail to respond to conventional treatments have been treated with isotretinoin, an effective treatment coming under strict regulation due to the risk of significant side effects. Photodynamic therapy (PDT) may be a viable alternative treatment for recalcitrant acne of various types and levels of severity. OBJECTIVE: To determine the safety and efficacy of combination PDT with topical 5-aminolevulinic acid (ALA) and activation by long-pulsed, pulsed dye laser (LP PDL, 595 nm) energy with topical therapy in patients with mild to severe acne. METHODS: A prospective, controlled pilot, proof-of-principle study of 19 consecutive patients (aged 16-47 years, Fitzpatrick skin types I-VI) with mild to severe cystic, inflammatory, or comedonal acne of the face was conducted. All patients had failed conventional therapy, including oral antibiotics, topical treatments, hormonal therapy, laser procedures (without ALA), and/or oral isotretinoin. Fifteen patients were treated with ALA PDT and 4 patients served as controls; all were continued on topical medications. Patients undergoing PDT were initially randomized to receive either blue light or laser energy. Because recrudescence occurred in 1 patient while undergoing multiple treatments with ALA and blue light, all subsequent patients were treated with ALA and laser energy. The total number of patients treated with LP PDL-mediated ALA PDT was 14. ALA was applied for a short 45-minute incubation followed by 1 minimally overlapping pass with the LP PDL (595 nm, 7.0-7.5 J/cm2 fluence, 10-ms pulse duration, 10-mm spot size, and dynamic cooling spray of 30 ms with a 30-ms delay). Patients treated with conventional therapy (oral antibiotics, oral contraceptives, and topical medications) or laser energy without ALA PDT served as control groups. Patients were followed monthly for up to 13 months. RESULTS: Complete clearance was achieved in 100% (14 out of 14) patients in the LP PDL PDT-treated group. A mean of 2.9 treatments (range 1-6; 2.0-3.7, 95% CI; n=14) was required to achieve complete clearance for a mean follow-up time of 6.4 months (range 1-13; 3.8-8.9 95% CI; n=14). The patient mean percent lesional clearance rate per treatment was 77% (64%-90%, 95% CI; n=14). Improvement in acne lesions became apparent within 1 to 2 weeks after the first treatment. Clearance in the LP PDL PDT group was superior to control groups. In the LP PDL-only control group (n=2), the patient mean percent lesional clearance rate per treatment was 32% without complete clearance after 3 to 4 treatments. In the oral antibiotics, oral contraceptives, and topicals control group (n=2), the clearance rate per treatment was 20%, the mean clearance rate per month was 4%, and complete clearance was not achieved after 6 to 10 months. In the LP PDL-mediated PDT group, treatments were well-tolerated with minimal erythema lasting 1 to 2 days. No cases of crusting, blistering, purpura, scarring, or dyspigmentation occurred. A reduction in the erythema in erythematous acne scars was observed. CONCLUSION: For teenage to adult patients with recalcitrant comedonal, inflammatory, or cystic acne of various degrees of severity, ALA PDT with activation by LP PDL appears to be a safe and effective treatment with minimal side effects. LP PDL-mediated PDT may serve as an important alternative to isotretinoin. Cosmetically well-accepted, LP PDL PDT combined with topical therapy is the first PDT modality to achieve complete clearance with long-term follow-up as compared to controls.
Three family members, at initial evaluation, had generalized comedonal lesions with histologic changes of acantholysis and dyskeratosis. A total of nine cases of this entity, termed familial dyskeratotic comedones, have been documented in the literature. It appears to have autosomal dominant inheritance and onset in childhood or adolescence. Lesions are asymptomatic except for occasional pruritus or inflammation, and general health is undisturbed. A history of acne vulgaris is seen in four of nine patients and is the only associated skin disease. Treatment with oral isotretinoin produced no improvement in two patients. Electron microscopy revealed changes similar to those seen in Darier's disease.
Ultrastructural examination of expressed "black" open comedones did not disclose any single melanosomes or melanosome complexes. If there is any melanin present in comedonal plugs, the amount is minimal, and it cannot be the source of the black color.
The detergent-soluble fraction of purified, concentrated comedo samples was analysed for protein by disc-gel electrophoresis and fluorescamine assay. Spectrophotometer scanning revealed a characteristic pattern of 14 peaks which was essentially uniform in comedones from individuals having acne, Favre-Racouchot syndrome, or prepubertal comedones. The pattern was different in material derived from keratinous cysts and the contents of follicles from the nose. The presence of small amounts of serum proteins, notably globulins, was detected by immunodiffusion.