Onychoschizia

Onychoschizia, also known as nail splitting and brittle nails, is a splitting of the free-edged tip of the nail.^[1] There is also often a longitudinal split in addition to the separation of keratin layers.^[2]

Cause[edit]

Frequent hand-washing is the usual cause, but it is also part of normal ageing.^[3] Manicures, nail polish and remover, nail biting, and repeated trauma such as typing, can contribute to nail splitting.^[1] Dehydration likely plays a role.^[3] Nutritional deficiencies that can result in nail splitting include iron, selenium, and zinc.^[1] Some skin diseases such as psoriasis and lichen planus may feature such nails.^[3]

Diagnosis[edit]

Diagnosis is by its appearance, but sometimes blood tests are required to look for iron deficiency, thyroid problems, and kidney problems.^[1]

Treatment[edit]

Treatment is by discontinuing nail polish and applying moisturiser.^[2] An acceptable alternative is gel nails.^[2] Some favourable response has been reported with biotin if the person is deficient in vitamin B₇.^[1] It is not routinely given.^[1]

Epidemiology[edit]

It is common among women and occurs in almost a third of newborns.^[2]

Other animals[edit]

It also occurs in hooved animals such as horses.^[4]

References[edit]

^ ^a ^b ^c ^d ^e ^f Sloan, Brett (2022). "16. Multiple nail: nail splitting". In Waldman, Reid A.; Grant-Kels, Jane M. (eds.). Dermatology for the Primary Care Provider. Philadelphia: Elsevier. pp. 277–278. ISBN 978-0-323-71236-1.
^ ^a ^b ^c ^d James, William D.; Elston, Dirk; Treat, James R.; Rosenbach, Misha A.; Neuhaus, Isaac (2020). "33. Diseases of the skin appendages". Andrews' Diseases of the Skin: Clinical Dermatology (13th ed.). Edinburgh: Elsevier. p. 785. ISBN 978-0-323-54753-6.
^ ^a ^b ^c Johnstone, Ronald B. (2017). "2. Diagnostic clues and "need-to-know" items". Weedon's Skin Pathology Essentials (2nd ed.). Elsevier. p. 31. ISBN 978-0-7020-6830-0.
^ Colombo, Victor E.; Gerber, Françoise; Bronhofer, Max; Floersheim, George L. (December 1990). "Treatment of brittle fingernails and onychoschizia with biotin: Scanning electron microscopy". Journal of the American Academy of Dermatology. 23 (6): 1127–1132. doi:10.1016/0190-9622(90)70345-i. PMID 2273113.

[Wald2022-1] ^ ^a ^b ^c ^d ^e ^f Sloan, Brett (2022). "16. Multiple nail: nail splitting". In Waldman, Reid A.; Grant-Kels, Jane M. (eds.). Dermatology for the Primary Care Provider. Philadelphia: Elsevier. pp. 277–278. ISBN 978-0-323-71236-1.

[Andrew2020-2] James, William D.; Elston, Dirk; Treat, James R.; Rosenbach, Misha A.; Neuhaus, Isaac (2020). "33. Diseases of the skin appendages". Andrews' Diseases of the Skin: Clinical Dermatology (13th ed.). Edinburgh: Elsevier. p. 785. ISBN 978-0-323-54753-6.

[Weedon2017-3] Johnstone, Ronald B. (2017). "2. Diagnostic clues and "need-to-know" items". Weedon's Skin Pathology Essentials (2nd ed.). Elsevier. p. 31. ISBN 978-0-7020-6830-0.

[pmid2273113-4] Colombo, Victor E.; Gerber, Françoise; Bronhofer, Max; Floersheim, George L. (December 1990). "Treatment of brittle fingernails and onychoschizia with biotin: Scanning electron microscopy". Journal of the American Academy of Dermatology. 23 (6): 1127–1132. doi:10.1016/0190-9622(90)70345-i. PMID 2273113.

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