What is dyskeratosis histology?
Dyskeratosis is the presence of premature or altered/ abnormal keratinocyte differentiation. Histologically the abnormal keratinocytes have increase/accumulation of keratin filaments leading to a hypereosinophilic cytoplasm (pinker on H&E) and shrunken hyperchromatic nuclei (ie, they are small and dark-staining).
What is acanthosis in histology?
Acanthosis is term pathologists use to describe an increased number of specialized squamous cells on the surface of a tissue. Acanthosis is commonly seen in the top layer of the skin called the epidermis.
What is Ortho and parakeratosis?
Orthokeratotic hyperkeratosis refers to the thickening of the keratin layer with preserved keratinocyte maturation, while parakeratotic hyperkeratosis shows retained nuclei as a sign of delayed maturation of keratinocytes. Hyperkeratosis can be associated with dyskeratosis.
What causes acanthosis?
Acanthosis nigricans often occurs in people who have disorders such as ovarian cysts, underactive thyroids or problems with the adrenal glands. Certain drugs and supplements. High-dose niacin, birth control pills, prednisone and other corticosteroids may cause acanthosis nigricans. Cancer.
What is acanthosis and papillomatosis?
Malignant acanthosis nigricans is a rare paraneoplastic skin syndrome mostly associated with gastric adenocarcinoma. Florid cutaneous papillomatosis and tripe palms syndrome are considered to be abortive clinical variants of acanthosis nigricans.
What does Cornified skin mean?
Cornification, the keratinocyte differentiation programme (occurring in upper layer), is a slow, coordinated process in space and time that allows the formation of a dead cells (corneocytes) layer to create a physical barrier for the skin.
Are keratinocytes squamous cells?
The Squamous Cell Layer Keratinocytes produce keratin, a tough, protective protein that makes up the majority of the structure of the skin, hair, and nails. The squamous cell layer is the thickest layer of the epidermis, and is involved in the transfer of certain substances in and out of the body.
What is the purpose of keratinocytes?
As the most dominant cell type constituting the epidermis, keratinocytes play multiple roles essential for skin repair. They are the executors of the re-epithelialization process, whereby keratinocytes migrate, proliferate, and differentiate to restore the epidermal barrier.