Amer M, Mostafa F F, Tosson Z, Nasr A N
Department of Dermatology, University of Zagazig, Faculty of Medicine, Egypt.
Int J Dermatol. 1996 Jun;35(6):417-21. doi: 10.1111/j.1365-4362.1996.tb03024.x.
The stratum corneum of some of the scaly (parakeratotic) diseases was examined with light and scanning electron microscopy (SEM) with the purpose to reveal the importance of this layer in the diagnosis of some of the diseases associated with the formation of scales.
Two biopsies of the skin surface were taken: one, obtained from 80 patients with various parakeratotic scaly diseases and from 25 control subjects, was processed for light microscopy; the other biopsy for SEM was taken from 10 control subjects and 25 patients. The diagnoses of these patients were: psoriasis (5 patients), erythrodermic psoriasis (2 subjects), parapsoriasis (5 patients), pityriasis rubra pilaris (5 subjects), pityriasis rosea (3 subjects), and seborrheic dermatitis (5 subjects).
The light microscopic studies showed that normal corneocytes are of polygonal shape with their largest diameter measuring 42 microns; these cells lacked nuclei. All parakeratotic cells appeared bizarre in shape, smaller than normal, and the cells contained a nucleus. With SEM, normal cells appeared relatively regular in size and shape, trabeculated, and had a flat surface. Cells examined in all the diseases revealed various sizes, outlines, and trabeculae. Specific surface patterns (print) of diseased cells were: "fish-scale" in psoriasis; "marbled" in parapsoriasis, "rocky stone" in pityriasis rubra pilaris; "heart-shaped" in seborrheic dermatitis, and semicrystalloid in pityriasis rosea.
Parakeratosis is characterized not only by the retention of the nucleus in keratinocytes, but is also characterized by a cell of smaller size. The specific print of a disease helps in the diagnosis. The print will change with different stages of a disease.
运用光学显微镜和扫描电子显微镜（SEM）对部分鳞屑性（角化不全）疾病的角质层进行检查，旨在揭示该层在某些与鳞屑形成相关疾病诊断中的重要性。
采集两份皮肤表面活检样本：一份取自80例患有各种角化不全性鳞屑疾病的患者以及25名对照者，用于光学显微镜检查；另一份用于SEM检查的活检样本取自10名对照者和25例患者。这些患者的诊断结果为：银屑病（5例）、红皮病型银屑病（2例）、副银屑病（5例）、毛发红糠疹（5例）、玫瑰糠疹（3例）以及脂溢性皮炎（5例）。
光学显微镜研究显示，正常角质形成细胞呈多边形，最大直径为42微米；这些细胞无细胞核。所有角化不全细胞形状怪异，比正常细胞小，且含有细胞核。通过SEM观察，正常细胞在大小和形状上相对规则，呈小梁状，表面平坦。在所有疾病中检查的细胞呈现出各种大小、轮廓和小梁。患病细胞的特定表面模式（印记）为：银屑病呈“鱼鳞状”；副银屑病呈“大理石状”；毛发红糠疹呈“岩石状”；脂溢性皮炎呈“心形”；玫瑰糠疹呈半晶体状。
角化不全不仅表现为角质形成细胞核的保留，还表现为细胞尺寸较小。疾病的特定印记有助于诊断。印记会随疾病的不同阶段而变化。
