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Nail Deformities and Dystrophies

By

Chris G. Adigun

, MD, Dermatology & Laser Center of Chapel Hill

Last full review/revision Aug 2019| Content last modified Aug 2019
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Topic Resources

Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are changes in nail texture or composition (eg, onychomycosis Onychomycosis Onychomycosis is fungal infection of the nail plate, nail bed, or both. The nails typically are deformed and discolored white or yellow. Diagnosis is by appearance, wet mount, culture, polymerase... read more Onychomycosis ).

Onychomycosis as a cause of nail dystrophy may be obvious on examination, but often samples of the nail plate and subungual debris are taken and sent for histopathologic examination and periodic acid-Schiff (PAS) examination, culture, or, more recently, polymerase chain reaction (PCR) analysis (1 General references Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more General references , 2 General references Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more General references ).

Nonfungal dystrophies may require a tissue biopsy of the nail plate or nail matrix to make a diagnosis. Nail dystrophy may resolve with treatment of the cause, but, if not, manicurists may be able to mask nail changes with appropriate trimming and polishes.

General references

  • 1. Hafirassou AZ, Valero C, Gassem N, et al: Usefulness of techniques based on real time PCR for the identification of onychomycosis-causing species. Mycoses 60(10):638–644, 2017. doi: 10.1111/myc.12629.

  • 2. Gupta AK, Nakrieko KA: Onychomycosis infections: Do polymerase chain reaction and culture reports agree? J Am Podiatr Med Assoc 107(4):280–286, 2017. doi: 10.7547/15-136.

Congenital nail deformities

In some congenital ectodermal dysplasias, patients have no nails (anonychia). In pachyonychia congenita, the nail beds are thickened, discolored, and transversely hypercurved (pincer nail deformity). Nail-patella syndrome Nail-Patella Syndrome Nail-patella syndrome is a rare inherited disorder of mesenchymal tissue characterized by abnormalities of bones, joints, fingernails and toenails, and kidneys. Diagnosis is clinical. There... read more causes triangular lunulae and partially absent thumb nails. Patients with Darier disease can have nails with red and white streaks and a distal V-shaped nick.

Nail deformities and dystrophies associated with systemic problems

Yellow nail syndrome is a rare condition characterized by slow-growing, thickened, hypercurved, yellow nails. This condition typically occurs in patients with lymphedema and/or chronic respiratory disorders. Chronic bronchial infections are present in about half of reported cases.

Half-and-half nails (Lindsay nails) occur usually with renal failure Chronic Kidney Disease Chronic kidney disease (CKD) is long-standing, progressive deterioration of renal function. Symptoms develop slowly and in advanced stages include anorexia, nausea, vomiting, stomatitis, dysgeusia... read more Chronic Kidney Disease ; the proximal half of the nail is white, and the distal half is pink or red-brown. Half-and-half nails occur in 20 to 50% of patients who have chronic kidney disease; however, this nail abnormality has been reported in various other chronic diseases including Crohn disease, cirrhosis, pellagra, and Kawasaki disease. This abnormality also occurs in healthy people (1 Systemic nail deformities and dystrophies reference Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Systemic nail deformities and dystrophies reference ).

Terry nails are characterized by whiteness of about 80% of the nail bed with a 0.5- to 3.0-mm brown to pink distal band. Terry nails are often associated with cirrhosis, chronic heart failure, and adult-onset diabetes mellitus. Differentiation from half-and-half nails can be difficult (1 Systemic nail deformities and dystrophies reference Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Systemic nail deformities and dystrophies reference ).

White nails occur with cirrhosis Cirrhosis Cirrhosis is a late stage of hepatic fibrosis that has resulted in widespread distortion of normal hepatic architecture. Cirrhosis is characterized by regenerative nodules surrounded by dense... read more , although the distal third may remain pinker. Intensely white nails, also called Terry nails, can be present in patients with chronic liver or kidney failure, heart failure, or diabetes. Terry nails are a type of leukonychia; the abnormality is not in the nail itself but rather the nail bed, causing the nail the appear white. In Terry nails, nearly the entire nail is opaque white and the lunula is not visible. There is a thin zone of normal pink nail bed at the distal edge of the nail. Terry nails may sometimes occur as part of normal aging (1 Systemic nail deformities and dystrophies reference Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Systemic nail deformities and dystrophies reference ).

Beau lines are horizontal grooves in the nail plate that occur when nail growth temporarily slows, which can occur after infection, trauma, systemic illness, or during cycles of chemotherapy. Onychomadesis similarly results from temporary growth arrest of the nail matrix and differs from Beau lines in that the full thickness of the nail is involved, causing a proximal separation of the nail plate from the nail bed. It most frequently occurs several months after hand-foot-and-mouth disease Hand-Foot-and-Mouth Disease (HFMD) Hand-foot-and-mouth disease (HFMD) is a febrile disorder usually caused by coxsackievirus A16, enterovirus 71, or other enteroviruses. Infection causes a vesicular eruption on the hands, feet... read more Hand-Foot-and-Mouth Disease (HFMD) but can occur after other viral infections. Nails affected by Beau lines or onychomadesis regrow normally with time.

Examples of Nail Deformities and Dystrophies Associated With Systemic Problems

Systemic nail deformities and dystrophies reference

  • 1. Pitukweerakul S, Pilla S: Terry's nails and Lindsay's nails: Two nail abnormalities in chronic systemic diseases. J Gen Intern Med 31(8):970, 2016. doi: 10.1007/s11606-016-3628-z.

Nail deformities associated with dermatologic conditions

In psoriasis Psoriasis Psoriasis is an inflammatory disease that manifests most commonly as well-circumscribed, erythematous papules and plaques covered with silvery scales. Multiple factors contribute, including... read more Psoriasis , nails may have a number of changes, including irregular pits, oil spots (localized areas of tan-brown discoloration), separation of part of the nail from the nail bed (onycholysis Onycholysis Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Onycholysis ), and thickening and crumbling of the nail plate. Nail psoriasis is independently associated with treatment-resistant psoriatic disease and is a risk factor for development of psoriatic arthritis Psoriatic Arthritis Psoriatic arthritis is a spondyloarthropathy and chronic inflammatory arthritis that occurs in people with psoriasis of the skin or nails. The arthritis is often asymmetric, and some forms involve... read more Psoriatic Arthritis . Treatment of nail psoriasis is challenging, but immunomodulatory agents are the most effective (1 Dermatologic nail deformities references Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Dermatologic nail deformities references , 2 Dermatologic nail deformities references Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Dermatologic nail deformities references ). Topical therapies can lead to modest improvement. Device-based therapies (eg, laser, light) need more study to judge their effectiveness.

Lichen planus Lichen Planus Lichen planus is a recurrent, pruritic, inflammatory eruption characterized by small, discrete, polygonal, flat-topped, violaceous papules that may coalesce into rough scaly plaques, often accompanied... read more Lichen Planus of the nail matrix initially causes potentially reversible nail changes, including longitudinal ridging, fissuring, erythema of the lunula, and distal splitting of the nail. Over time, scarring and irreversible changes may occur, including nail atrophy, pterygium formation, and total nail loss. Lichen planus of the nail unit requires management early in the disease to prevent permanent disfigurement. Treatment options include topical, intralesional, and systemic corticosteroids. However, relapse may occur after therapy in some patients. Pterygium of the nail, which is caused by lichen planus, is characterized by scarring from the proximal nail outward in a V formation, which leads ultimately to nail loss.

Alopecia areata Alopecia Areata Alopecia areata is typically sudden patchy nonscarring hair loss in people with no obvious skin or systemic disorder. (See also Alopecia.) This photo shows patchy loss of scalp hair in alopecia... read more Alopecia Areata can be accompanied by regular pits that form a geometric pattern. Pits are small and fine. Alopecia areata may also be associated with severe onychorrhexis (brittleness with nail breakage). Treatment options include intralesional and topical corticosteroids and topical sensitizers such as squaric acid dibutylester. Newer therapies including tofacitinib and apremilast have shown some promise.

Examples of Nail Deformities Associated With Dermatologic Conditions

Dermatologic nail deformities references

  • 1. van de Kerkhof P, Guenther L, Gottlieb AB, et al: Ixekizumab treatment improves fingernail psoriasis in patients with moderate-to-severe psoriasis: Results from the randomized, controlled and open-label phases of UNCOVER-3. J Eur Acad Dermatol Venereol 31(3):477–482, 2017. doi: 10.1111/jdv.14033.

  • 2. Merola JF, Elewski B, Tatulych S, et al: Efficacy of tofacitinib for the treatment of nail psoriasis: Two 52-week, randomized, controlled phase 3 studies in patients with moderate-to-severe plaque psoriasis. J Am Acad Dermatol 77(1):79–87, 2017. doi: 10.1016/j.jaad.2017.01.053.

Discoloration

Cancer chemotherapy drugs (especially the taxanes) can cause melanonychia (nail plate pigmentation), which can be diffuse or may occur in transverse bands. Some drugs can cause characteristic changes in nail coloration:

  • Quinacrine: Nails appear greenish yellow or white under ultraviolet light.

  • Cyclophosphamide: The onychodermal bands (seal formed at the junction of the nail plate and distal nail bed at the free edge of the nail plate) become slate-gray or bluish.

  • Arsenic: Nails may turn diffusely brown.

  • Tetracyclines, ketoconazole, phenothiazines, sulfonamides, and phenindione: Nails may have brownish or blue discoloration.

  • Gold therapy: Nails may be light or dark brown.

  • Silver salts (argyria): Nails may be diffusely blue-gray.

Tobacco smoking or nail polish can result in yellow or brownish discoloration of nails and fingertips.

White transverse lines of the nails (Mees lines) may occur with chemotherapy, acute arsenic intoxication, malignant tumors, myocardial infarction, thallium and antimony intoxication, fluorosis, and even during etretinate therapy. These lines are not due to changes in the nail bed, but are a true leukonychia, and the nails can grow out normally if the insulting exposure has been removed. Mees lines also develop with trauma to the finger, although traumatic white lines usually do not span the entire nail.

The fungus Trichophyton mentagrophytes causes a chalky white discoloration of the surface of the nail plate.

Green-nail syndrome is caused by infection with Pseudomonas. It is generally a harmless infection, usually of 1 or 2 nails, and is noteworthy for its striking blue-green color. It often occurs in patients with onycholysis Onycholysis Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Onycholysis or chronic paronychia Chronic Paronychia Chronic paronychia is recurrent or persistent nail fold inflammation, typically of the fingers. (See also Overview of Nail Disorders.) Chronic paronychia is an inflammatory disorder of the nail... read more Chronic Paronychia whose nails have been exposed to irritants or have had excessive exposure to water. If the onycholysis or chronic paronychia is treated effectively, the Pseudomonas infection will resolve. Patients should avoid irritants and excess moisture. Frequent clipping of the nail increases the response to treatment.

Median nail dystrophy (median canaliform dystrophy)

Median nail dystrophy is characterized by small cracks in the nail that extend laterally and look like the branches of an evergreen tree (eg, fir tree, such as a Christmas tree). The cracks and ridges are similar to those seen in habit-tic nail deformity (which is dystrophy of the central nail caused by repetitive trauma to the nail matrix resulting from rubbing or picking with another finger). The cause of median nail dystrophy is unknown in some cases, but trauma is thought to play a role. Frequent use of personal digital devices that subject the nails to repetitive striking has been implicated in several cases. Tacrolimus 0.1% at bedtime without occlusion has been successful when patients stop all activities that might lead to repetitive low-level trauma.

Melanonychia striata

Melanonychia striata are hyperpigmented bands that are longitudinal and extend from the proximal nail fold and cuticle to the free distal end of the nail plate. Pigmentation results from deposition of melanin by melanocytes in the nail matrix. Deposition of melanin is increased by melanocyte activation (increased production of melanin in the nail cells) or by melanocytic hyperplasia (increased production of melanocytes in the nail matrix).

Melanocyte activation may be a normal physiologic variant in people with darker skin. This variant, often called ethnic melanonychia, requires no treatment. Other causes of melanocyte activation include trauma, pregnancy, Addison disease and other endocrine disorders, infections, postinflammatory hyperpigmentation, and the use of certain drugs, including doxorubicin, 5-fluorouracil, zidovudine, and psoralens.

Melanocytic hyperplasia can be caused by benign conditions, such as nail matrix melanocytic nevus or nail lentigo, or by malignant melanoma. Factors more often associated with malignant melanoma of the nail matrix include new onset after middle age, presence of pigmentation on the dominant thumb or hallux, rapid growth or darkening, bandwidth > 3 mm, associated nail plate dystrophy, or Hutchinson sign (extension of hyperpigmentation onto the proximal and/or lateral nail fold). Rapid biopsy and treatment are essential in cases of suspected melanoma Treatment Malignant melanoma arises from melanocytes in a pigmented area (eg, skin, mucous membranes, eyes, or central nervous system). Metastasis is correlated with depth of dermal invasion. With spread... read more Treatment (1 Melanonychia striata reference Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Melanonychia striata reference ).

Melanonychia striata reference

  • 1. Leung AKC, Lam JM, Leong KF, Sergi CM: Melanonychia striata: Clarifying behind the black curtain. A review on clinical evaluation and management of the 21st century. Int J Dermatol Apr 21, 2019. doi: 10.1111/ijd.14464.

Onychogryphosis

Onychogryphosis is a nail dystrophy in which the nail, most often on the big toe, becomes thickened and curved. It may be caused by ill-fitting shoes. It is common among the elderly. Treatment consists of trimming the deformed nails.

Onycholysis

Onycholysis is separation of the nail plate from the nail bed or complete nail plate loss. It can occur as a drug reaction in patients treated with tetracyclines (photo-onycholysis), doxorubicin, 5-fluorouracil, cardiovascular drugs (particularly practolol and captopril), cloxacillin and cephaloridine (rarely), trimethoprim/sulfamethoxazole, diflunisal, etretinate, indomethacin, isoniazid, griseofulvin, and isotretinoin. Simple (ie, not associated with another nail or skin disorder) onycholysis may also result from exposure to irritants, such as frequent exposure to water, citrus fruits, or chemicals. Irritant contact dermatitis Irritant contact dermatitis (ICD) Contact dermatitis is inflammation of the skin caused by direct contact with irritants (irritant contact dermatitis) or allergens (allergic contact dermatitis). Symptoms include pruritus and... read more Irritant contact dermatitis (ICD) of the hands and fingers may lead to onycholysis (1 Onycholysis reference Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Onycholysis reference ). Colonization of the nail bed with Candida albicans may occur, but treating the underlying irritant exposure leads to resolution of the onycholysis, with or without treating the Candida.

Onycholysis reference

  • 1. Vélez NF, Jellinek NJ: Simple onycholysis: A diagnosis of exclusion. J Am Acad Dermatol 70(4):793–794, 2014. doi: 10.1016/j.jaad.2013.09.061.

Onychotillomania

In this disorder, patients pick at and self-mutilate their nails, which can lead to parallel transverse grooves and ridges (washboard deformity or habit-tic nail deformity). It most commonly manifests in patients who habitually push back the cuticle on one finger, causing dystrophy of the nail plate as it grows. Subungual hemorrhages Subungual hematoma and nail bed trauma Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Subungual hematoma and nail bed trauma can also develop in onychotillomania.

Pincer nail deformity

Pincer nail deformity is a transverse over-curvature of the nail plate. It is most often caused by onychomycosis Onychomycosis Onychomycosis is fungal infection of the nail plate, nail bed, or both. The nails typically are deformed and discolored white or yellow. Diagnosis is by appearance, wet mount, culture, polymerase... read more Onychomycosis , psoriasis Psoriasis Psoriasis is an inflammatory disease that manifests most commonly as well-circumscribed, erythematous papules and plaques covered with silvery scales. Multiple factors contribute, including... read more Psoriasis , tumors of the nail apparatus, and poorly fitting shoes. It has also been reported in patients with systemic lupus erythematosus Systemic Lupus Erythematosus (SLE) Systemic lupus erythematosus is a chronic, multisystem, inflammatory disorder of autoimmune etiology, occurring predominantly in young women. Common manifestations may include arthralgias and... read more Systemic Lupus Erythematosus (SLE) , Kawasaki disease Kawasaki Disease Kawasaki disease is a vasculitis, sometimes involving the coronary arteries, that tends to occur in infants and children between the ages of 1 year and 8 years. It is characterized by prolonged... read more Kawasaki Disease , end-stage renal disease Chronic Kidney Disease Chronic kidney disease (CKD) is long-standing, progressive deterioration of renal function. Symptoms develop slowly and in advanced stages include anorexia, nausea, vomiting, stomatitis, dysgeusia... read more Chronic Kidney Disease , and some genetic syndromes (eg, paronychia congenita). Patients often have pain at the borders of the nail where the nail plate curves into the tips of the fingers. There is no established treatment of choice, but a number of surgical techniques have been successful (1 Pincer nail deformity references Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Pincer nail deformity references , 2 Pincer nail deformity references Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Pincer nail deformity references , 3 Pincer nail deformity references Deformities are often considered together with dystrophies, but the two are slightly different; deformities are generally considered to be gross changes in nail shape, whereas dystrophies are... read more Pincer nail deformity references ).

Pincer nail deformity references

  • 1. Demirkıran ND: Suture treatment for pincer nail deformity: An inexpensive and simple technique. Dermatol Surg Feb 6, 2019. doi: 10.1097/DSS.0000000000001818.

  • 2. Shin WJ, Chang BK, Shim JW, et al: Nail plate and bed reconstruction for pincer nail deformity. Clin Orthop Surg 10(3):385–388, 2018. doi: 10.4055/cios.2018.10.3.385.

  • 3. Won JH, Chun JS, Park YH, et al: Treatment of pincer nail deformity using dental correction principles. J Am Acad Dermatol 78(5):1002–1004, 2018. doi: 10.1016/j.jaad.2017.08.014.

Subungual hematoma and nail bed trauma

Subungual hematoma occurs when blood becomes trapped between the nail plate and nail bed, usually as a result of trauma. Subungual hematoma may cause significant and throbbing pain, bluish black discoloration, and, unless small, eventual separation and temporary loss of the nail plate. When the cause is a crush injury, underlying fracture and nail bed or matrix damage may occur. Nail bed or matrix damage may result in permanent nail deformity.

If the injury is acute, nail trephination (eg, creating a hole in the nail plate using a cautery device, 18-gauge needle, or red-hot paperclip) can help relieve pain by draining accumulated blood; after 24 hours, blood is coagulated, thus trephination offers no benefit. It is not clear whether removing the nail and repairing any nail bed damage reduces risk of permanent nail deformity.

Trachyonychia

Nail tumors

Examples of Nail Tumors
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