Keratosis pilaris rubra: a common but underrecognized condition

BACKGROUND: Keratosis pilaris is a common skin disorder of childhood that often improves with age. Less common variants of keratosis pilaris include keratosis pilaris atrophicans and atrophodermia vermiculata. OBSERVATIONS: In this case series from dermatology practices in the United States, Canada, Israel, and Australia, the clinical characteristics of 27 patients with keratosis pilaris rubra are described. Marked erythema with follicular prominence was noted in all patients, most commonly affecting the lateral aspects of the cheeks and the proximal arms and legs, with both more marked erythema and widespread extent of disease than in keratosis pilaris. The mean age at onset was 5 years (range, birth to 12 years). Sixty-three percent of patients were male. No patients had atrophy or scarring from their lesions. Various treatments were used, with minimal or no improvement in most cases. CONCLUSIONS: Keratosis pilaris rubra is a variant of keratosis pilaris, with more prominent erythema and with more widespread areas of skin involvement in some cases, but without the atrophy or hyperpigmentation noted in certain keratosis pilaris variants. It seems to be a relatively common but uncommonly reported condition.     

头皮糜烂性脓疱性皮病1例

报告1例头皮糜烂性脓疱性皮病.患者女,82岁,因右侧头皮颞部反复出现红斑、脓疱、糜烂、结痂3个月就诊.皮肤科检查:右侧头皮颞部见大片红斑、糜烂、结痂,中间部分毛发脱落,皮肤轻度萎缩,浅表疤痕形成.皮损组织病理示:浅表糜烂结痂,表皮不规则增生,部分表皮轻度萎缩,真皮浅层可见以淋巴、组织细胞、浆细胞及少量中性粒细胞为主的混...     

Laser treatment of atrophoderma vermiculata

Atrophoderma vermiculata is a rare genodermatosis with usual onset in childhood, characterized by a "honey-combed" reticular atrophy of the cheeks. The course is generally slow, with progressive worsening. We report successful treatment of 2 patients by means of the carbon dioxide and 585 nm pulsed dye lasers.     

The effect of topical crude coal tar treatment on unstimulated hairless hamster skin

Topical treatment of hairless hamster skin with crude coal tar has been shown to induce epidermal thickening, an increased labelling index in the basal cell layer, an elevation in NADP-dependent glucose-6-phosphate dehydrogenase activity throughout the epidermis, an increased squame count, comedo formation, and atrophy of the sebaceous glands. Ultraviolet light fluorescence microscopy of sections of treated skin suggests that the hair follicle is an important route for skin penetration by coal tar.     

Towards the development of a simplified long-term organ culture method for human scalp skin and its appendages under serum-free conditions

Organ culture of human scalp skin is usually performed with serum-containing medium, which limits its analytical usefulness. Here we report that intact human scalp skin can be grown at the air/liquid interface in supplemented, serum-free William's E medium for more than 2 weeks. Active hair shaft growth was visible until day 16 and was significantly enhanced compared with minimum essential medium (MEM) + 10% fetal bovine serum (FBS). Moreover, William's E medium protected better against cell death than MEM + 10% FBS before day 12. Using quantitative immunochemistry, proliferating (Ki-67+) cells could still be observed in the epithelium of hair follicles even on day 17 of serum-free skin organ culture. The number of apoptotic (TUNEL+) cells in the skin epithelium rose steadily after day 5. Giemsa stains revealed mature skin mast cells even after 13 days in culture. The percentage of surviving hair follicles (mostly with catagen- or telogen-like morphology) gradually increased over time displaying mostly catagen hair follicles after 17 days of culture. Although epidermis and hair follicle epithelium showed increasing atrophy and degeneration, and their pigmentation decreased gradually over time, some long-term-surviving epithelial islands were found in association with remnants of follicular structures as late as on day 88. These preliminary data suggest that a very simple serum-free organ culture method allows prolonged human skin and hair follicle survival as well as some limited hair follicle cycling in intact skin for more than 2 weeks under well-defined experimental conditions. This pragmatic assay invites multiple uses, and may become a valuable tool for both skin and hair research.     

PERIFOLLICULAR ELASTOLYSIS

SUMMARY.— We report a skin disease in 3 women characterized clinically by small, grey or white, finely wrinkled, round or oval lesions with a central hair follicle, occurring on the neck, ear-lobes, arms and upper trunk. Balloon-like bulging of some lesions was present. Histologically, there was loss of elastic fibres immediately surrounding hair follicles, without inflammation or decrease in collagen. A bacterial aetiology of this condition, a perifollicular variant of primary macular atrophy, was suggested when an elastase-producing strain of Staphylococcus epidermidis was found in the hair follicles located within lesions. A selective loss of elastic fibres without collagen breakdown was produced by in vitro incubation of normal human skin in bacteria-free extracts of culture media on which elastase-positive Staph. epidermidis had been grown.     

线状皮肤型红斑狼疮1例

患者女,11岁,因鼻梁右侧及鼻根至额部带状暗红丘疹8个月余就诊。实验室检查提示ENA、抗核抗体及抗心磷脂抗体均无异常,组织病理检查提示表皮萎缩,可见毛囊角栓,基底层细胞液化变性,血管及附属器周围团块状淋巴细胞、组织细胞浸润。符合线状皮肤型红斑狼疮的诊断。     

Plasticity of hair follicle dermal cells in wound healing and induction

The capacity of adult hair follicle dermal cells to participate in new follicle induction and regeneration, and to elicit responses from diverse epithelial partners, demonstrates a level of developmental promiscuity and influence far exceeding that of interfollicular fibroblasts. We have recently suggested that adult follicle dermal cells have extensive stem or progenitor cell activities, including an important role in skin dermal wound healing. Given that up to now tissue engineered skin equivalents have several deficiencies, including the absence of hair follicles, we investigated the capacity of follicle dermal cells to be incorporated into skin wounds; to form hair follicles in wound environments; and to create a hair follicle-derived skin equivalent. In our study, we implanted rat follicle dermal cells labelled with a vital dye into ear and body skin wounds. We found that they were incorporated into the new dermis in a manner similar to skin fibroblasts, but that lower follicle dermal sheath also assimilated into hair follicles. Using different combinations of follicle dermal cells and outer root sheath epithelial cells in punch biopsy wounds, we showed that new hair follicles were formed only with the inclusion of intact dermal papillae. Finally by combining follicle dermal sheath and outer root sheath cells in organotypic chambers, we created a skin equivalent with characteristic dermal and epidermal architecture and a normal basement membrane - the first skin to be produced entirely from hair follicle cells. These data support the hypothesis that follicle dermal cells may be important in wound healing and demonstrate their potential usefulness in human skin equivalents and skin substitutes. While we have made progress towards producing skin equivalents that contain follicles, we suggest that the failure of cultured dermal papilla cells to induce follicle formation in wounds illustrates the complex role the follicle dermis may play in skin. We believe that it demonstrates a genuine dichotomy of activity for follicle cells within skin.     

Ichthyosis follicularis with alopecia and photophobia

We treated two unrelated boys with ichthyosis follicularis, a rare skin disorder characterized by extensive noninflammatory spiny follicular hyperkeratoses, severe photophobia, and generalized noncicatricial alopecia. This disorder must be differentiated from keratosis follicularis spinulosa decalvans; ulerythema ophryogenes; keratosis pilaris rubra atrophicans faciei; atrichia with papular lesions; atrophodermia vermiculata; and keratitis, ichthyosis, and deafness syndrome, all of which share some clinical features. Ichthyosis follicularis with alopecia and photophobia appears to be a familial disorder, but too few cases have been reported to establish the exact mode of inheritance.     

Tissue measurements in senile sebaceous gland hyperplasia

Senile sebaceous gland hyperplasia has been studied in 18 subjects in an attempt to shed some light on its pathogenesis. The sizes of different segments of the pilosebaceous unit were compared in senile sebaceous gland hyperplasia (SGH) and in control skin samples, using stereological techniques. The whole follicle was found to be significantly increased in volume compared with follicular structures in the control specimens. The size of differentiated sebaceous gland cells was found to be reduced compared with controls (490 +/- 72 microns 2 and 554 +/- 98 microns 2, respectively), but not significantly so. The mean tritiated thymidine autoradiographic labelling index determined in vitro was found to be decreased (5.42 +/- 1.79) compared with controls (7.48 +/- 2.44), but again, not significantly so. In addition the degree of solar elastotic degenerative change was found to be similar in SGH bearing skin compared with control samples. It is of interest that SGH and prostatic hypertrophy are exceptions to the usual atrophy of ageing and that both tissues are androgen dependent.     

Getting under the skin of hair aging: the impact of the hair follicle environment

Like the skin, our hair shows striking changes with age, producing hairs with altered diameter, lustre and texture. The biology of hair aging has focused predominately on various aspects of the hair cycle, follicle size and the fibre produced, but surprisingly the impact of the aging scalp dermal environment on the hair follicle and fibre has been generally overlooked. Hair loss affects both sexes with incidence increasing with age. In men, male pattern-balding (androgenetic alopecia) is driven by androgens and follows a specific pattern of frontotemporal and vertex regression. Women also experience female pattern hair loss (FPHL), presenting as more general, diffuse hair thinning. Hair thinning in women is commonly associated with the menopause, corresponding with other age-related changes in skin. The rapidly growing hair follicle undergoes continued renewal throughout the life span of an individual, where it is exposed to a substantial number of extrinsic and intrinsic stressors. As the hair follicle sits deep within the dermis with its bulb residing in the hypodermis, detrimental age-related changes in the surrounding scalp skin may likely disrupt the hair follicle machinery. The impacts of these changes are unknown, but evidence suggests that scalp skin aging and hair follicle aging go hand-in-hand. Herein, we summarize the evidence that the age-related changes observed in sun-exposed human skin also occur in scalp skin and that these changes are likely to play a contributing role in the aging hair phenotype.     

Gadolinium toxicity: epidermis thickness measurement by magnetic resonance imaging at 500 MHz

Purpose: Regional epidermal thickening and hair follicle width measurement by delayed gadolinium contrast magnetic resonance imaging (MRI) may assess the contrast agent gadolinium toxicity on mice skin. Materials and methods: Delayed contrast in vivo MRI was performed in mice. Six mice skin samples were removed and exposed to a gadolinium contrast agent at different times after 2, 4, 6 and 8 h. The relaxation constants of each skin structure were measured. The thickness of the epidermis and hair follicle on follow‐up ex vivo delayed‐contrast MRI served as an index of gadolinium toxicity on the skin. Results: In vivo MRI by fast low‐angle shot imaging technique showed distinct skin layers. High‐resolution gradient echo T1‐weighted and multislice multiecho proton density‐weighted MRI intensities in the epidermis and hair follicle showed a positive correlation with delayed gadolinium‐enhanced MRI hyperintensities (Pearson's correlation coefficient r²=0.81, P<0.0001) in the excised mice skin tissues. Delayed contrast‐enhanced mice skin MRI after 2–4 h showed epidermis swelling and hair follicle regions with a size measurement accuracy of 65%, a sensitivity of 95%, a specificity of 25%, a positive predictive value of 65% and a negative predictive value of 65%. Areas under the receiver operating characteristic curves by MRI were 0.92–0.94 for hair and epidermis as good discriminators. MRI visualized distinct relaxation constants of the epidermis, sebaceous gland, skin papillary and reticular dermis layers and hair follicle. Conclusion: Gadolinium contrast‐enhanced MRI may visualize the thickening of the epidermis wall and hair follicle as an index of viable mice skin. Gadolinium enhanced the MRI visibility of skin structures. Gadolinium treatment showed skin toxicity as epidermis thickening the first time due to the undesirable use of high concentrations of gadolinium in microimaging.     

Keratosis follicularis spinulosa decalvans

Keratosis follicularis spinulosa decalvans is a rare, X-linked disorder of keratinization of the hair follicle with inflammation and atrophy associated with corneal dystrophy and other symptoms. A family with several affected members is reported. The unaffected parents were related. A 12-year-old girl and her 5-year-old brother had follicular spiny hyperkeratoses on the trunk and extremities. The girl had thinning of the eyelashes and eyebrows as well as scarring alopecia of the scalp as additional features of the disease. Both the girl and her brother had corneal dystrophy and photophobia. Two sisters aged 8 and 10 years did not show similar skin or eye findings.     

毛乳头细胞体外诱导毛囊上皮细胞分化的实验研究

目的:探讨间质细胞对毛囊上皮细胞分化的调节作用,研究毛囊上皮细胞的分化特性。方法:分别用团块状的毛乳头细胞、皮肤成纤维细胞制成间质细胞胶原凝胶,表面接种毛囊上皮细胞,进行气-液界面培养。结果:毛囊上皮细胞有向毛乳头细胞移动集结的趋势;团块状的毛乳头细胞诱导毛囊上皮细胞形成球形结构;皮肤成纤维细胞诱导毛囊上皮细胞形成表皮样层化结构。结论:(1)毛囊上皮细胞具有双向分化特性,它既能分化形成毛囊,也能分化形成表皮结构;(2)毛乳头细胞对毛囊上皮细胞有趋化作用;(3)间质细胞的种类及分布在毛囊上皮细胞分化的调节中起着重要的作用。     

Is growth hormone a radioprotective agent?

There is currently substantial clinical interest in growth hormone (GH) as a protective agent against radiation-related normal tissue injury. To further assess the potential radiation injury-preventive effects of GH, these effects were studied in rats by using a radiation-induced skin injury model. Group 1 received neither GH nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (radiation group). Group 3 and 4 received the same irradiation plus either 0.01 U/kg/day GH (RT + 0.01 GH group) or 0.02 U/kg/day GH (RT + 0.02 GH group) subcutaneously. Clinically and histopathologically, acute skin reactions were assessed by two independent experts in radiation oncology and pathology, respectively. Irradiation increased dermatitis in rats when compared with the control group. The severity of radiodermatitis in the rats in the RT + 0.01 GH and RT + 0.02 GH groups was significantly lower than that in the RT group; radiodermatitis developed earlier in the RT group than in the other groups. GH was efficacious in preventing epidermal atrophy, dermal degeneration such as oedema and collagen fibre loss, and hair follicle atrophy, but not better than in the control group. These results are preliminary to studies that will be performed with higher doses of GH in radiation-treated cancer patients, with the aim of reducing radiation-induced toxicity.     

On-line diffusion profile of a lipophilic model dye in different depths of a hair follicle in human scalp skin

In skin and hair research, drug targeting to the hair follicle is of great interest in the treatment of skin diseases. The aim of this study is to visualize on-line the diffusion processes of a model fluorophore into the hair follicle at different depths using fresh human scalp skin and confocal laser scanning microscopy. Up to a depth of 500 microm in the skin, a fast increase of fluorescence is observed in the gap followed by accumulation of the dye in the hair cuticle. Penetration was also observed via the stratum corneum and the epidermis. Little label reached depths greater than 2000 microm. Fat cells accumulated the label fastest, followed by the cuticular area and the outer root sheath of the hair follicle. Sweat glands revealed very low staining, whereas the bulb at a depth of 4000 microm was visualized only by autofluorescence. From this study, we conclude that on-line visualization is a promising technique to access diffusion processes in deep skin layers even on a cellular level. Furthermore, we conclude that the gap and the cuticle play an important role in the initial diffusion period with the label in the cuticle originating from the gap.     

Hair follicle reformation induced by dermal papilla cells from human scalp skin

To investigate the possibility of hair follicle reformation induced by dermal papilla cells in vivo and in vitro. Dermal papilla cells, dermal sheath cells obtained from human scalp skin by enzyme digestion were mixed with collagen to form mesenchymal cell-populated collagen gels. Superior and inferior epithelial cells and bulb matrical cells were then cultured on these gels by organotypic culture to recombine bilayer artificial skins. Dermal papilla cells and outer root sheath keratinocytes were mingled together and transplanted under subcutaneous tissue of the dorsal skin of nude mice. The results of histologic examination was observed with HE stain. These recombinants by organotypic culture all reformed bilayer structure like nature skin. Hair follicle-like structure reformation was found in dermal sheath cell-populated collagen gel when combined with superior or inferior epithelial cells. Dermal papilla cells also induced superior and inferior epithelial cells to form hair follicle on nude mice. Low passage dermal papilla cells mixed with hair follicle epithelial cells reformed many typical hair follicle structures and produced hair fibres after transplantation on nude mice. The dermal part of hair follicle, such as dermal papilla cells and dermal sheath cells, has the ability to induce hair follicle formation by interaction with the epithelial cells of hair follicle.     

Variations of hair follicle size and distribution in different body sites

For the evaluation and quantification of follicular penetration processes, the knowledge of variations of hair follicle parameters in different body sites is basic. Characteristics of follicle sizes and potential follicular reservoir were determined in cyanoacrylate skin surface biopsies, taken from seven different skin areas (lateral forehead, back, thorax, upper arm, forearm, thigh, and calf region). The highest hair follicle density and percentage of follicular orifices on the skin surface and infundibular surface were found on the forehead, whereas the highest average size of the follicular orifices was measured in the calf region. The highest infundibular volume and therefore a potential follicular reservoir was calculated for the forehead and for the calf region, although the calf region showed the lowest hair follicle density. The calculated follicular volume of these two skin areas was as high as the estimated reservoir of the stratum corneum. The lowest values for every other parameter were found on the forearm. The present investigation clearly contradicts former hypothesis that the amount of appendages of the total skin surface represents not more than 0.1%. Every body region disposes its own hair follicle characteristics, which, in the future, should lead us to a differential evaluation of skin penetration processes and a completely different understanding of penetration of topically applied drugs and cosmetics.     

Unravelling hair follicle–adipocyte communication

Here, we explore the established and potential roles for intradermal adipose tissue in communication with hair follicle biology. The hair follicle delves deep into the rich dermal macroenvironment as it grows to maturity where it is surrounded by large lipid‐filled adipocytes. Intradermal adipocytes regenerate with faster kinetics than other adipose tissue depots and in parallel with the hair cycle, suggesting an interplay exists between hair follicle cells and adipocytes. While adipocytes have well‐established roles in metabolism and energy storage, until recently, they were overlooked as niche cells that provide important growth signals to neighbouring skin cells. We discuss recent data supporting adipocytes as niche cells for the skin and skin pathologies that may be related to alterations in skin adipose tissue defects.