Orthokeratosis

Orthokeratosis
Synonyms	Orthokeratotic hyperkeratosis
Pronounce	N/A
Specialty	N/A
Symptoms	Thickening of the stratum corneum with normal keratinocyte maturation
Complications	None specific, but may be associated with other skin conditions
Onset	Varies depending on underlying cause
Duration	Chronic or acute, depending on etiology
Types	N/A
Causes	Psoriasis, ichthyosis, eczema, lichen planus, actinic keratosis
Risks	Genetic predisposition, environmental factors
Diagnosis	Skin biopsy, histopathology
Differential diagnosis	Parakeratosis, hyperkeratosis, dyskeratosis
Prevention	N/A
Treatment	Depends on underlying condition; may include topical corticosteroids, emollients, keratolytics
Medication	N/A
Prognosis	Generally good with appropriate management of underlying condition
Frequency	Common in conditions like psoriasis and ichthyosis
Deaths	N/A

Orthokeratosis is a term used in dermatology to describe a condition where the stratum corneum layer of the skin is composed of fully differentiated keratinocytes.

Overview

Orthokeratosis is characterized by the presence of anucleate squamous cells in the stratum corneum. This is a normal finding in the epidermis of the skin, but can also be seen in certain pathological conditions such as psoriasis, lichen planus, and actinic keratosis.

Pathology

In orthokeratosis, the stratum corneum is thickened due to the accumulation of anucleate squamous cells. This is in contrast to parakeratosis, where the stratum corneum is composed of nucleated squamous cells. The presence of orthokeratosis can be confirmed through a skin biopsy and subsequent histopathological examination.

Clinical Significance

Orthokeratosis is often associated with a variety of skin conditions. In psoriasis, it is seen as part of the characteristic "psoriasiform" epidermal hyperplasia. In lichen planus, orthokeratosis occurs in areas of epidermal thickening known as "Wickham's striae". In actinic keratosis, orthokeratosis is seen in areas of sun-damaged skin.

See Also

• Stratum corneum
• Keratinocyte
• Psoriasis
• Lichen planus
• Actinic keratosis