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PubMedDate not supplied

Comedone formation: etiology, clinical presentation, and treatment.

An important feature in the etiology of acne is the presence of pilosebaceous ductal hypercornification, which can be seen histologically as microcomedones (Fig 1) and clinically as blackheads, whiteheads, and other forms of comedones, such as macrocomedones. There is a significant correlation between the severity of acne and the number and size of microcomedones (follicular casts), the presence of which is a measure of comedogenesis. This correlation can be demonstrated by skin surface biopsy using cyanoacrylate gel. In this procedure, microcomedones are sampled by applying cyanoacrylate gel to the skin surface. A glass microscopic slide is then applied on top of the gel and pressed firmly onto the skin for 1 minute(1-3). The glass slide is gently removed, taking with it the upper part of the stratum corneum and microcomedones, which are then analyzed by low-power microscopy or digital image analysis.(1-3)

Acne Vulgaris↗
PubMed1983

Actinic comedonal plaque of the eyelid.

A variety of actinic lesions occur on the eyelids and facial skin. Actinic comedonal plaque is an unusual entity that falls into this category. We successfully treated such a lesion with cryotherapy.

Actins↗
PubMed1999

Pilotropic mycosis fungoides presenting with multiple cysts, comedones and alopecia.

We report a 45-year-old man with mycosis fungoides (MF) who presented with multiple epidermoid cysts, comedones and alopecia and who responded to treatment with intravenous and oral cyclophosphamide. The pilotropic variant of MF, characterized histologically by follicular lesions and pilotropism without mucinosis, is uncommon and often resistant to treatment.

Alopecia↗
PubMed1998

A pilot study on bacterial viability in acne. Assessment using dual flow cytometry on microbials present in follicular casts and comedones.

BACKGROUND: Antibiotic therapy is one of the main methods of acne treatment, however, bacterial resistance is on the rise and can affect the treatment outcome. Quantitative bacteriologic cultures are the gold standard methodology for the assessment of such a problem; however, certain important biological aspects remain uncovered. OBJECTIVE: The purpose of this study was to compare the antibacterial activity of minocycline and lymecycline in sebaceous follicle infundibula and comedones of acne patients. METHOD: We used a recently introduced flow cytometric method, allowing a distinction to be made between viable, injured (presumably resistant), and dead microorganisms. RESULTS: Minocycline (100 mg) proved to be superior to lymecycline (600 mg) in abating the microflora harboring in the sebaceous follicles of acne patients. CONCLUSIONS: The dissimilar bioavailability and antimicrobial efficacy between the two bacteriostatic agents may impart different clinical efficacy.

Acne Vulgaris↗
PubMed1985

The composition of the ceramides from human stratum corneum and from comedones.

Human epidermal surface lipids were collected by an ethanol wash and the ceramides were quantified by thin-layer chromatography-photodensitometry. Six ceramide fractions were isolated and the structural components of each were analyzed in detail. The most unusual of the epidermal ceramides contained a sphingosine base with amide-linked 30- and 32-carbon omega-hydroxyacids and an ester-linked nonhydroxyacid, 41% of which was linoleic acid. The proportion of linoleic acid in the analogous ceramide from comedones was 6%. This supports the hypothesis that a localized insufficiency of linoleic acid in the follicular epithelium is an etiologic factor in comedogenesis.

Acne Vulgaris↗
PubMed1996

An ultrastructural study of the retention hyperkeratosis of experimentally induced comedones in rabbits: the effects of three comedolytics.

The precise pathologic processes of comedo formation in acne are not well understood. Retention hyperkeratosis may play an important role. To evaluate the effects of three topical comedolytics, 20% azelaic acid, 0.1% tretinoin and 5% benzoyl peroxide, on the retention hyperkeratosis of experimentally induced comedones (EIC), an ultrastructural study was done. After formation of EIC with 50% oleic acid in paraffin oil on the external ears of rabbits, each comedolytic was applied for 4 weeks. Biopsies were taken every week and, using a Hitachi H-600 transmission electron microscope, morphologic observations were done in the upper portion of the follicular epithelium. In EIC, after application of each comedolytic, the markedly thinned horny layer was loosely adhered by extremely few desmosomes and desmosomal bodies. The number and size of tonofilaments and keratohyaline granules decreased, but the number of variable sized Odland bodies increased in the upper epidermis. These findings appeared 1 week after application of either azelaic acid or benzoyl peroxide, and 3 weeks after application of tretinoin. For the first 2 weeks of tretinoin application, EIC showed rather compact hyperkeratosis with more desmosomes and desmosomal bodies than before. Azelaic acid tretinoin and benzoyl peroxide increased the number of Odland bodies, and the horny cells became less adhesive. This lysis of retention hyperkeratosis resulted in comedolysis. During 4 weeks of treatment with these three comedolytics, only tretinoin normalized the keratinization process.

Acne Vulgaris↗
PubMed1979

The effect of vitamin A acid on experimentally induced comedones: an electron microscope study.

Various concentrations of vitamin A acid were applied to experimentally induced comedones. All concentrations produced non-cohesive hyperkeratinization, which loosened the cohesive horny mass induced by oleic acid and expelled it from the follicle within 7 days. The highest concentration (0.1%) produced the greatest degree of non-cohesive desquamation in the shortest time. In follicles treated with the acid, the cell membrane of horny cells was thin and ruptured easily to produce a non-cohesive debris. Desmosomes were scarce and desmosomal bodies (fusiform electron-dense bodies) and tight junctions between horny cells were not seen in follicles treated with the acid. The acid also produced hyperplasia of the epithelial wall and an apparently increased mitotic rate. A 0.025% concentration of the acid increased the number of membrane coating granules by about 70% in all regions of the follicle.

Acne Vulgaris↗
PubMed1995

Comedonal Darier's disease.

Darier's disease is an inherited disorder with well-recognized patterns of presentation. Lesions commonly affect the trunk and flexures. The diagnosis is based on the typical clinical appearance and histology showing acantholytic dyskeratosis. We report two unusual cases with prominent nodular, comedonal lesions on the face and scalp.

Aged↗
PubMed1996

Congenital nasal comedones--report of three cases.

We report on three patients with black or white comedones arranged along the nasal groove in the distal third of the nose between the alar and triangular cartilages. This peculiar disorder is probably more common than would appear from the small number of cases so far reported in the literature.

Acne Vulgaris↗
PubMedDate not supplied

Trichostasis spinulosa: a clinical simulant of acne open comedones.

Trichostasis spinulosa is a disorder of the pilosebaceous follicles that may simulate acne open comedones. It is a commonly reported cosmetic annoyance in adults but not children. A review of the literature and a case of trichostasis spinulosa in a 13-year-old black girl with a history of onset at 18 months of age are presented.

Acne Vulgaris↗
PubMed1984

A newly recognized feature of ectrodactyly, ectodermal dysplasia, clefting (EEC) syndrome: comedone naevus.

A 21-year-old Black South African man with clinical features of ectrodactyly, ectodermal dysplasia, cleft lip/palate (EEC) syndrome is described. The patient had the following anomalies: hypoplastic, peg-shaped teeth; fine, silky hair; absent lacrimal puncta resulting in secondary photophobia, blepharitis and corneal opacities. The hands and feet showed absent digits, symphalangism and displacement of bone consistent with ectrodactyly. In addition, the patient had extensive comedone naevus, a feature not previously reported in EEC syndrome. We stress that the dysplastic ectodermal features of EEC syndrome are not typical of either hidrotic or anhidrotic ectodermal dysplasia but fall into a class of their own. Clefting of the lip and palate were absent due, it is postulated, to the variable expressivity of EEC syndrome.

Adult↗
PubMed1976

Topically applied antibiotics in acne vulgaris: clinical response and suppression of Corynebacterium acnes in open comedones.

Topical antibiotics were used on patients with acne vulgaris. Corynebacterium acnes organisms from open comedones were quantitated during treatment, and the progress of the disease was evaluated. Clindamycin lotion completely suppressed the growth of C acnes organisms, whereas erythromycin and tetracycline did not depress the C acnes counts. Taken as a group, these antibiotics gave a substantial improvement of the disease on the treated side as compared with paired untreated sides of the face and back.

Acne Vulgaris↗
PubMed1976

[Ultrastructure and microflora in follicles and comedones].

The resident flora of skin surface, sebaceous follicles, and acne comedones: Pityrosporum, micrococci, and corynebacterium (propionibacterium) acnes is described. The nomenclature, topography, incidence, pathogenic role, and especially the ultrastructural morphology of these organisms are presented.

Acne Vulgaris↗
PubMedDate not supplied

Two sisters with familial dyskeratotic comedones.

Familial dyskeratotic comedones is a rare autosomal dominant genodermatosis, which presents with disseminated keratotic papules and comedo-like lesions. The disease usually manifests in childhood. The histology of the lesions is characterized by a crater-like invagination of the epidermis filled with parakeratotic keratin. The epidermis usually shows acantholysis. So far the causative gene defect is unknown. We report on a new family with two affected sisters. The more severely affected woman was treated with oral retinoids without any effect. Afterwards some regions were successfully treated by CO(2) laser-therapy.

Adult↗
PubMed1978

Familial comedones. Evidence for autosomal dominant inheritance.

Thirteen members of a family had multiple comedones. Three other relatives were also ascertained to be affected. This peculiar dermatosis affected both sexes and was present in one individual as young as 10 years of age. The lesions were more numerous in male family members, increasing in number with age. The pedigree showed a definite pattern of autosomal dominant inheritance.

Acne Vulgaris↗
PubMed1980

[Propionibacterium acnes in acne vulgaris (comparative biochemical study of the comedone and the pustule].

The biochemical properties of the Propionibacterium acnes in 22 patients with inflammatory Acne vulgaris was studied. Group I/II was found in most cases. There was no difference between the biochemical properties of the comedone and the pustule. The authors suggest that factors other than those depending on the PA degradative metabolism can be responsible for the purulent inflammatory process of the pil-sebaceous follicle.

Acne Vulgaris↗