Hair counts in scalp biopsy of males and females with androgenetic alopecia compared with normal subjects

Background:  Hair counts were studied in scalp biopsy specimens of androgenetic alopecia (AGA) in male and female patients. We also assessed the normal value of hair count in scalp biopsy specimen from Iranians and compared with published data.
Methods:  Thirty subjects with clinically normal scalps, 25 male and 28 female patients with AGA were studied. Vertical and horizontal sections of 4-mm punch biopsy specimens were examined at various levels from the papillary dermis to the subcutis. Hair counts of total, terminal, vellus, anagen and telogen hairs were obtained by ocular micrometer.
Results:  Hair counts were not significantly different from published data in American Whites but significantly higher in Iranians compared with Koreans (p < 0.001). There was no significant difference between male and female patients with AGA. Perifollicular inflammation was lower in both the normal subjects and the patients compared with other studies.
Conclusion:  In AGA patients, total and vellus hairs were lower and terminal to vellus (T:V) ratio was higher than the results of previous studies in Whites (p < 00.1). T:V ratio of control group was significantly higher in this study compared with previous published data. Perhaps the higher ratio than the reported data could means the onset of miniaturization.     

Hair and scalp dermatoscopy

Dermatoscopy is a noninvasive diagnostic tool that allows the recognition of morphologic structures not visible by the naked eye. Trichoscopy (scalp dermatoscopy and videodermatoscopy) is useful for the diagnosis and follow-up of hair and scalp disorders. However, it is not widely used in the management of hair disorders. This review provides updated information from the literature and our experience on the dermoscopic features of the most common hair and scalp disorders. This will enable dermatologists to make fast diagnoses of tinea capitis and alopecia areata, distinguish early androgenetic alopecia from telogen effluvium, and differentiate scarring from nonscarring alopecia.     

Hair and scalp disorders in blacks

Hair and scalp disorders in blacks and the properties of hair in blacks that make it behave differently are described. Hair disorders commonly seen now are the result of permanent and relaxer damage, heat, and traction alopecias. Presently, the most common scalp disorders in blacks are keloidal folliculitis and dissecting cellulitis of the scalp. Treatment modalities for these disorders are reviewed.     

Hair and scalp disorders in ethnic populations

Treating scalp and hair disorders is challenging because of the emotional nature of hair loss and because of unknown pathogenesis. Treating African American patients can add an extra layer of complexity to this treatment if the dermatologist is not familiar with hair care practices. Only the dermatologist who strives to understand hair care practices, the common disease entities of the hair and scalp in African Americans, and the disturbance in quality of life from alopecia will effectively approach treatment in these patients.     

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.     

Dermoscopy guided scalp biopsy in cicatricial alopecia

Background Scalp biopsies are crucial for the diagnosis of cicatricial alopecia. However, the pathologic interpretation may not be diagnostic if biopsy is not obtained from the correct site. This is particularly relevant for cicatricial alopecia as the disease may be focal and disease activity difficult to appreciate by the naked eye. Objective To report a new simple technique to select the optimal biopsy site in cicatricial alopecia. Methods In the last 2 years we performed dermoscopy guided scalp biopsies using handled dermatoscopes in 80 patients with different forms of cicatricial alopecia. Biopsy site was selected based on presence of the following dermatoscopic features: perifollicular concentric white scales in lichen planopilaris, frontal fibrosing alopecia (FFA) and discoid lupus erythematosus (DLE); hair tufts in folliculitis decalvans, hairs surrounded by a peripilar grey‐white halo in central centrifugal cicatricial alopecia and follicular red dots or keratotic plugs in DLE. Results The dermoscopy guided biopsies yielded a definitive pathological diagnosis in 95% of the cases. Comment The advantage of this method is that it is a fast, precise way to identify even individually affected follicles in early or focal cicatricial alopecia. It also allows for the morphologic characterization of particular follicular structures.     

Vertical vs. transverse sections of scalp biopsy specimens: a pilot study on the comparison of the diagnostic value of two techniques in alopecia

Background. Using both vertical and transverse sections is preferred for histopathological diagnosis of alopecia. However, in cases in which only a single biopsy is taken, it is not clear which type of sectioning is better. Aim. To compare the diagnostic value of transverse and vertical sections. Methods. In total, 53 patients with alopecia were enrolled in the study. Two biopsies were taken from each patient, and cut into either transverse or vertical sections. The clinical and histopathological findings were evaluated together for the definitive diagnosis. After the study period, a pathologist randomly re‐evaluated the sections. We compared the histopathological diagnoses with the definitive diagnoses, and determined the sensitivity and specificity of each method. Results. A definitive diagnosis was made for 47 patients (88.7%). Of these, 30 (63.8%) had noncicatricial and 17 (36.2%) had cicatricial alopecia, and the diagnosis was made by transverse and vertical sections for 43 (91.5%) and 39 (88%), respectively (P > 0.05; sensitivity; 91.5% vs. 82%). All 30 patients with noncicatricial alopecia were diagnosed by transverse sections, and 25 (83.3%) of the 30 were diagnosed with vertical sections (P = 0.05; sensitivity 100% vs. 83.3%). Of the 17 patients with cicatricial alopecia, 13 (76.5%) and 14 (82.4%) patients were diagnosed by transverse and vertical sections, respectively (P > 0.05; sensitivity 76.5% vs. 82.4%). Five patients with lichen planopilaris were diagnosed by vertical sections, and one by transverse sections. There were several limitations to the study: (i) statistical subtype analysis could be performed only for alopecia areata; (ii) no conclusion could be drawn about the interobserver reliability of two sections; and (iii) having the pathologist‐blinded study performed retrospectively might have caused a recall bias. Conclusion. If only a single biopsy specimen is available, it may be preferable to have transverse sections in cases of suspected noncicatricial alopecia, and vertical sections in cases of suspected lichen planopilaris. Either type of sectioning is suitable for cicatricial alopecia when lichen planopilaris is clinically unlikely.     

Agar embedding of curetted biopsy specimens for histopathologic examination.

Fragmented, small curettings are embedded in 3% bacterial agar at the time of tissue biopsy. These small tissue specimens are trapped within the agar and tissue loss is minimized. This method eliminates the additional steps of spinning the fragments (that are usually suspended in formaldehyde) or filtering the contents. The agar method concentrates the tissue specimen and keeps the tissue better oriented. The end result is preservation of all fragments submitted with some retention of tissue specimen orientation. Ease of laboratory preparation is another substantial benefit.     

Cutaneous cryoanesthesia does not affect histopathology of biopsy specimens.

Localized freezing of skin lesions in situ is widely used by dermatologists to provide anesthesia prior to excision or curettage. To determine whether this technique adversely affects the interpretation of biopsy specimens, we compared the histopathologic features of frozen and unfrozen portions of nine skin lesions, eight seborrheic keratoses, and one basal cell carcinoma. We detected no differences in the histopathologic features between the frozen and unfrozen portions of the lesions. We conclude that the technique of cutaneous cryoanesthesia does not adversely affect the histopathologic evaluation of skin lesions.     

Hair growth in scalp grafts from patients with alopecia areata and alopecia universalis grafted onto nude mice

A basic question in both mild and severe forms of alopecia areata (AA) relates to whether the disease is inherent to the affected tissue or secondary to circulating factors. This question has been addressed by grafting 2-mm grafts of scalp from affected areas of seven patients with AA or alopecia universalis (AU) onto congenitally athymic (nude) mice. Hair growth in these grafts has been compared with that of 2-mm grafts from hair-bearing skin remnants from two individuals undergoing elective plastic surgical procedures. Because cyclosporine seems to directly affect hair growth, a group of grafted mice was treated with this agent. By day 48, hair growth was present in many surviving grafts. Cyclosporine affected hair growth; this was most prominent by day 78 when the number of hairs per graft and the mean length of hair had increased significantly over untreated groups. Grafts from patients with AU had more hairs per graft and had greater hair length than did similar grafts from patients with AA. These experiments show that hair growth ability in situ is likely normal in AA and AU, and that the factors causative to this disease in situ are mediated humorally. Furthermore, cyclosporine seems to directly influence hair growth in this model system.     

实时荧光定量PCR检测石蜡标本中麻风菌DNA

目的：评价实时定量荧光PCR(Real-time PCR)法检测石蜡标本中麻风菌DNA的应用价值。方法：根据基因库(GenBank)发表的M. leprae的全基因组序列,以一段重复序列(repetitive ele￣ment,RLEP)为扩增靶序列,合成引物和探针,构建质粒pGEMT-101作为标准品,用Real-time PCR对石蜡标本进行麻风菌DNA检测,并评价其敏感性。结果：对52例麻风患者的石蜡包埋组织标本麻风菌进行了检测,不同型别麻风(LL：8;BL：10;BT：28;TT：6)的石蜡标本检测阳性率分别为100％(8/8)、80％(8/10)、78.57％(22/28)、50％(3/6)。结论： Real-time PCR方法可在石蜡标本中快速灵敏的检测到麻风菌DNA。