Parakeratosis

Parakeratosis is a condition of the skin characterized by the persistence of nuclei in the stratum corneum. In normal skin, the stratum corneum does not contain nuclei. Parakeratosis can be observed in various skin diseases, including psoriasis and actinic keratosis.

Definition

Parakeratosis is defined as the presence of nuclei in the stratum corneum of the skin. This is an abnormal finding, as in healthy skin, the stratum corneum is anuclear, meaning it does not contain nuclei. The presence of nuclei indicates a disturbance in the process of keratinization, the process by which skin cells mature and move to the surface of the skin.

Causes

Parakeratosis can be caused by a variety of skin conditions, including psoriasis, actinic keratosis, and seborrheic dermatitis. It can also be caused by physical or chemical irritants, such as excessive scrubbing of the skin or exposure to harsh chemicals. In some cases, parakeratosis may be a normal variant, such as in the mucosa of the mouth or the skin of the palms and soles.

Diagnosis

The diagnosis of parakeratosis is made by a dermatologist or a pathologist on the basis of a skin biopsy. The biopsy sample is examined under a microscope, and the presence of nuclei in the stratum corneum is indicative of parakeratosis.

Treatment

The treatment of parakeratosis depends on the underlying cause. If the condition is caused by an irritant, the irritant should be avoided. If it is caused by a skin disease, the disease should be treated. Treatment options may include topical creams, oral medications, or light therapy.

See also

• Keratinocyte
• Stratum corneum
• Dermatology

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  Micrograph of early actinic keratosis with parakeratosis
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  Histopathology of reactive hyperkeratosis