91 - Nail Disorders Flashcards
Complete or almost complete lack of the nail
Anonychia
Severe hypoplasia
Hyponychia
No terminal phalanx and no nail growth
Cooks syndrome
Atelephalangia with anonychia
Half-side index fingernail hypoplasia and a Y-shaped radiologic alteration of the distal phalanx
Iso-Kikuchi syndrome
May be a sign of phenytoin and alcohol fetopathy
Constant feature of congenital onychodysplasia of Iso-Kikuchi
Micronychia
Short wide nail, mostly of the thumb which develops from the age of 12 years
Result of a premature ossification of the epiphysis of the distal phalanx
Racket nail
Very short nails
May develop in patients under chronic hemodialysis who develop a tertiary hyperparathyroidism with resorption of the bone if the terminal phalanx
Brachyonychia
Relatively frequent finding in subjects of all races
Nail may be slightly wider and have a slight longitudinal indentation or be discernible as a complete accessory nail
Rudimentary double nail of the fifth toe
Most common color change of the nail
Leukonychia
Many longitudinal white bands are characteristic of
Hailey-Hailey disease
Result of nail bed pallor
May disappear with temperature change or pressure
Apparent leukonychia
Pair of 2 whitish transverse lines
Sign of hypoalbuminemia
Muehrcke lines
White surface of the nail, which is infected by fungi
Pseudoleukonychia
Red nails
Erythronychia
Multiple red bands are commonly caused by
Inflammatory conditions such as lichen planus
Single red band may represent
Specific tumors such as onychopapilloma or Bowen disease
Alternating narrow white and red bands are seen in
Darier disease
Green nails
Chloronychia
In almost all cases, chloronychia is caused by
Colonization of the nail by Pseudomonas aeruginosa
Treatment of choice of P. aeruginosa colonization
Soaking in diluted white vinegar, 2 or 3 times daily for 10 minutes, then brushing the fingers dry
Y/N: Systemic antibiotics do not reach the site of infection because Pseudomonas mainly colonizes an onycholytic nail
Yes
Seen developing in persons swimming in water with copper sulfate as a disinfective agent
Blue nails or glauconychia
Slate-gray to bluish nail matrix is a sign of
Argyria
Exogenous agents that may stain the nail brown
Potassium permanganate
Tobacco smoke
Silver nitrate
Multiple melanonychias in several or all digits are common in
Dark-skinned individuals and Asians and are a physiologic phenomenon seen in almost all African Americans
Association of lenticular labial, oral, and genital mucosal brown spots with melanonychias is characteristic for
Laugier-Hunziker-Baran syndrome
Most frequent sign of nail melanoma
Longitudinal nail pigmentation
Never reaches into the free margin of the nail plate (one of the most reliable criteria for differential diagnosis)
Does not form a regular longitudinal band
Subungual hematoma
Hematomas occupying more than 50% of the nail field are commonly associated with
Fracture of the distal phalanx
Narrow red to almost black longitudinal lines in the distal nail bed
Caused by blood that is enclosed in subungual keratin
Splinter hemorrhages
_____ splinter hemorrhages may be a sign of trichinosis
Oblique
Detachment of the nail from the distal nail bed
Onycholysis
Cause of onycholysis semilunaris
Direct trauma resulting from overzealous nail cleaning
Sharply delineated proximal margins that may look like a half moon
Onycholysis semilunaris
Characteristic for onychomycoses and psoriasis
Subungual hyperkeratosis
Subungual hyperkeratosis is virtually always associated with onycholysis, except in
Pachyonychia congenita
Nail covers an excessive nail bed hyperkeratosis in a horseshoe-like fashion
Pachyonychia congenita
Exaggeration of nail bed and matrix hyperkeratosis
Often has the shape of a ram’s horn
Onychogryposis
Onychogryposis is mainly seen in
Elderly, neglected and debilitated individuals
Bridging of the nail pocket by connective tissue, in most cases scars
Very common in lichen planus, but is occasionally seen in bullous pemphigoid and after trauma
Pterygium
When the nail plate does not separate correctly from the nail plate at the hyponychium and remains attached, a painful hyperkeratosis obliterates the distal groove
Quite common in acral scleroderma and Raynaud syndrome
Pterygium inversum
A temporary slowdown or even arrest of nail formation results in a transverse groove that runs parallel to the lunula border
Beau lines
Result of a longer-lasting arrest of nail matrix proliferation that eventually results in a proximal gap in the nail and proximal onycholysis
Onychomadesis
Small depressions in the nail surface resulting from minute foci of abnormal keratinization of the apical matrix
Pits
Most characteristic and most frequent sign of nail psoriasis
Pitting
Rough nails
Trachyonychia
Result of pressure on the nail matrix, usually the result of a small tumor in the promixal nailfold
Longitudinal groove
Multiple longitudinal fissures, often associated with nail thinning and ridges
Onychorrhexis
Lamellar splitting of the nail at its free end
Onychoschizia
In babies with _____, onychoschizia is common
Koilonychia
The most common type is _____ ingrowing of the edge of the big toenail
Distal-lateral
Proximal ingrowing of the nail
Lunula is no longer present
Retronychia
Overcurvature of the nails
Pincer nails
Systemic radiographic examination of the toes show that the distal phalanx is asymmetrical and often shows
Distally pointing exophytes
Skin disease with the most frequent nail involvement
Psoriasis
Y/N: There is an association of human leukocyte antigen (HLA)-C0602 with nail and joint involvement in psoriasis
No - In contrast to skin, there is an association of human leukocyte antigen (HLA)-C0602 with nail and joint involvement
_____ pits per nail or more than _____ pits on all nails are seen as proof of nail psoriasis
10
50
Rarely, _____ are seen in the lunula usually representing a very active psoriasis lesion with dilation of the capillaries and thinning of the suprapapillary plate
Red spots
Seen when the psoriatic lesion is in the mid to distal matrix and parakeratotic cells are incorporated into the nail plate
Leukonychia
Analogous to Auspitz phenomenon on the skin and result from damage to the dilated capillaries
Splinter hemorrrhages
Represent psoriatic plaques in the distal matrix and the nail bed
Salmon spots
Yellowish-brownish spot with a red margin
Salmon spot
Psoriatic onycholysis typically has a _____ differentiating it from most other causes of onycholysis
Reddish proximal margin
Condition closely related to psoriatic arthritis but usually without obvious nail changes
Big toe is considerably thickened and often painful
Psoriatic pachydermoperiostosis
3 different forms of pustular psoriasis, all of which also involve the nail
Palmar plantar pustular psoriasis of Barber-Konigsbeck
Generalized pustular psoriasis of von Zumbusch
Acrodermatitis continua suppurativa of Hallopeau
A mutation in the gene for _____ leading to a defect in _____ was found in generalized pustular psoriasis and acrodermatitis continua suppurativa
Interleukin-36 receptor antagonist
Very similar to pustular psoriasis
Usually have a more brownish tint because of the content of erythrocytes in their pustules
Histopathology also shows spongiform pustules
Reiter disease
In nai psoriasis, _____, even though often being rather inconscpicuous, are the most resistant to treatment
Pits
A 3-month trial of _____ is warranted in nail psoriasis
Combination of a vitamin D3 derivative with a potent corticosteroid
Y/N: The less of the nail is present, the easier is penetration of the drug to the very psoriatic lesion
Yes
_____ injections were also given in nail psoriasis with some success; however, this cytostatic drug may slow down nail growth and make an improvement visible only very late
Methotrexate
Nummular eczema of the nail region mainly involves the
Proximal nailfold
Shiny nails are characteristic in _____ of children and young, and middle-aged adults. These individuals “learned” not to harm their skin by scratching with the free margin of the nails and to relieve the itch by rubbing with the back of the distal phalanx
Chronic itchy atopic dermatitis
Desquamation and cracking of the finger and toe tips and is often also a feature of atopic winter feet
Atopic pulpitis sicca
Rough nails
Hallmark of the so-called 20-nail dystrophy
Trachyonychia
In the author’s experience, most cases of trachyonychia are caused by
Atopic dermatitis
The rare occurrence of allergic and irritant contact dermatitis on toenails as compared to fingernails points at the importance of
Nail cosmetics as well as a number of household allergens
Painful matrix and nail bed dermatitis is characteristic of _____ allergy
Acrylate
The more severe the AA, the (more/less) likely is nail involvement
More
Two types of nail alterations are seen in AA
Rough nails that have lost their shine
Pitted nails with surface shine
Sign of very severe in involvement in AA
Koilonychia
Y/N: The pathogenesis in AA on the nails in contrast to the hair appears to be variable
Yes - Nails do not fall off in contrast to hair
Histopathologic pattern of inflammation in hair follicles and nails are different
Nail biopsy of AA shows
Spongiotic dermatitis with lymphocyte exocytosis involving the matrix
In nail lichen planus, most commonly, the _____ is involved
Apical matrix
The similarity of clinical and histopathological nail alerations in _____ with those of lichen planus has supported the view that it is an autoimmune disorder
Graft-versus-host disease
Y/N: Once a pterygium has developed, nail lichen planus is no longer amenable to treatment
Yes
Most common initial signs of autoimmune bullous diseases affecting the nail unit
Chronic paronychia with oozing and crust formation
Perinugual erythema and red lunula may be seen in
Acute lupus erythematosus
Pernio-like nonspecific violaceous-blue hue with some telangiectasias to ulceration of the tip of the toe and the nail unit
Chillblain lupus
Red streaks in the nail bed, ridging of the nail, and dystrophy
Chronic discoid lupus erythematosus
Ulceration of the pulp and narrowing of the tip of the finger
Nail insidiously bends volarly giving the aspect a parrot beak
Scleroderma with its acral variant
Most important Herpesviridae affecting the nail
HSV type 1 (HHV1)
HSV type 2 (HHV2)
Varicella-zoster virus (HHV3)
HHV8
Y/N: Primary herpes simplex infection usually causes nail lesions
No - rarely
Small vesicles are seen to develop that first have a clear content, which, after some days, becomes yellowish while the blisters tend to merge
Visible red streak is commonly seen extending from the finger to the arm; this lymphangitis is usually associated with pain
Herpes virus infection
In children, recurrent digital herpes simplex is usually caused by
HHV1
In adults, _____ are the causative agents of recurrent digital herpes simplex
HHV1 and HHV2
Y/N: There are no controlled studies proving the value of long-term antiviral prophylaxis for herpes virus infections
Yes
Common warts: On the proximal nailfold, they are _____ papules with a rough keratotic surface; on the lateral folds they are often _____
Round
Oval
Infection with HPV types _____ is the most common cause for viral warts of the nail unit
1, 2, 3, 4, and 7
Intraoral aphthoid lesions that cause less discomfort than common aphthous ulcers, with small vesicles on the palms, soles, and around the nails
Characteristic slightly oval vesicles with a gray blister and a narrow red margin
In ridged skin, the long axis of the vesicles is along the dermatoglyphics
Hand-foot-and-mouth disease
In most cases, the cause of hand-foot-and-mouth disease is an infection with
Enterovirus type 71
Coxsackievirus, mainly type A5 and A16
The most characteristic bacterial infection is a _____ that runs around the proximal part of the nail, hence the common term runaround
Bullous impetigo
When the infection occurs primarily under the nail it is called a
Subungual whitlow
Recurrent digital herpes simplex vs bullous impetigo
More painful
Develops a lymphangitis
Starts with a group of clear blisters that coalesce and later becomes putrid
The matrix in children may be permanently damaged within _____ in a subungal whitlow
24 to 48 hours
Most frequent nail disorders making up approximately 40% to 50% of all nail diseases
Onychomycoses
Vast majority of onychomycoses are _____ subungual onychomycoses
Distal or
Distal-lateral
Condition mostly seen in the toenails as chalky-white patches with no shine of the nail surface
Superficial white onychomycosis
When occurring on fingernails, the white discoloration is inhomogeneous and more cloudy, but the nail surface remains shiny; this is the typical form of HIV infections
Superficial white onychomycosis
Rare form in which the fungus only grows in the nail plate without affecting the subungual tissue
Dermatoscopy may show air-filled channels in the nail plate
Endonyx onychomycosis
The matrix in children may be permanently damaged within _____ in a subungal whitlow
24 to 48 hours
Most frequent nail disorders making up approximately 40% to 50% of all nail diseases
Onychomycoses
Vast majority of onychomycoses are _____ subungual onychomycoses
Distal or
Distal-lateral
Condition mostly seen in the toenails as chalky-white patches with no shine of the nail surface
Superficial white onychomycosis
When occurring on fingernails, the white discoloration is inhomogeneous and more cloudy, but the nail surface remains shiny; this is the typical form of HIV infections
Superficial white onychomycosis
Rare form in which the fungus only grows in the nail plate without affecting the subungual tissue
Dermatoscopy may show air-filled channels in the nail plate
Endonyx onychomycosis
Primary total dystrophic onychomycosis is characteristic for _____ which represents a group of immune defects with impaired defense against Candida albicans
Chronic mucocutaneous candidiasis
Huge amounts of compressed mostly very thick-walled fungi
Dermatophytoma
In onychomycosis, the rate of false-negative results, particularly for _____, is very high, commonly between 30% and 60%, but _____ has proved to be doubly sensitivit
Culture
Histopathology
Y/N: Histopathology can distinguish between colonization and true infection
Yes
Unilateral clubbing may hint at
Arterial insufficiency of this extremity
Condition of toenails, in which onycholysis usually affects 1 corner of the big toenail
Asymmetric gait nail unit syndrome
When more than _____% of the nail is affected or the infection reaches the matrix at any point, systemic treatment is indicated
50
Characteristic sign of chronic hypoxemia
Frequently indicates cor pulmonale
Clubbing
The angle between the proximal nailfold and the nail plate (_____) is greater than 180 degrees
Angle of Lovibond
The nails may turn _____ in Wilson disease
Bluish
Unilateral clubbing may hint at
Arterial insufficiency of this extremity
Yellow nail syndrome is a characteristic triad of signs
Yellow, thick, extremely slow-growing nails with onycholysis, often also spontaneous nail loss and complete disappearance of the cuticle
Chronic sinus-bronchopulmonary infection
Edema of the distal extremities
Periungual erosions with crusting
Nail edges may break through the epidermis of the nail grooves and cause granulation tissue
Acrodermatitis enteropathica
Acquired zinc deficiency
In severe liver disease, the nails may turn white and opaque
Distal normal-colored band remains
Terry nails
2 parallel white bands in the middle of the nail bed that do not move out
Seen in severe hypoalbuminemia
Muehrcke lines
The nails may turn _____ in Wilson disease
Bluish
Proximal half of the nail is whitish, the distal half tends to be brownish
Seen in chronic renal insufficiency and under long-term hemodialysis
Half-and-half nails
Chewing of the nails
Onychophagia
Picking of the periungual skin
Perionychotillomania
This habit tic results in a central depression of the nail with a washboard aspect, an unusually long lunula and loss of cuticle
Perionychotillomania
Toxic doses of vitamin _____ are destructive of the nail
A
Nails are virtually rubbed away
Onychoteiromania
Cutting device is used to remove the nail
Onychotemnomania
Patients bite on their nails in the lunula or proximal nail bed region to produce pain
Onychodaknomania
Has been successfully used in a number of obsessive-compulsive disorders, including autoaggressive nail conditions
N-acetyl cysteine
High doses of _____ cause transverse white nail discoloration
Arsenic
Toxic doses of vitamin _____ are destructive of the nail
A
Some drugs cause characteristic, although rarely specific, nail alterations. They are most often observed under the treatment with
Cytotoxic drugs
May cause painful subungual hemorrhagic abscesses that may require withdrawal of the drug
Taxanes
Acyclovir induces
Longitudinal melanonychia
Retinoids are associated with
Fragile nails
Paronychia
Beta-blockers induce
Acral ischemia
Bleomycin may lead to
Digital ischemia
Permanent nail loss
Photochemotherapy with psoralens and UVA can induce _____ in several nails
Multiple longitudinal brown streaks
Rarely seen during administration of some tetracyclines and fluoroquinolones, as it is painful, may be hemorrhagic, and occurs in the central nail bed of 1 or more nails
Photoonycholysis
Three types of hypohidrotic ectodermal dyplasias
Autosomal recessive
X-linked
Autosomal dominant
Group of 5 molecular biologically well-defined diseases of cytokeratosis KRT6a, KRT6b, KRT6c, KRT16, and KRT17
Pachyonychia congenita
Painful callus-like palmar and plantar hyperkeratoses, monstrous thickening of the subungual hyperkeratosis that is covered by a horseshoe-like nail usually of normal thickness
Oral leukokeratosis with no potential for malignant degeneration
Natal teeth
Vellus hair cysts
Pachyonychia congenita
By definition, ectodermal dysplasia is any hereditary disorder involving at least _____ of the cutaneous adnexa - hair, nails, sweat glands, teeth
2
If resolution of congenital malalignment of the big toenail has not started by age _____, it will likely not occur
2 years
Systematic radiographic examinations of congenital malalignment of the big toe
Lateral deviation of the distal phalanx (hallux valgus interphalangeus)
Three types of hypohidrotic ectodermal dyplasias
Autosomal recessive
X-linked
Autosomal dominant
Consequence of repeated blistering of the nail organ and leaves smooth digit tips covered with a shiny epidermis
Anonychia
Caused by a mutation in the homeobox gene LMXB1, which is necessary for the anterior-posterior orientation during organogenesis
Nail-patella syndrome
Pigmentary abnormalities of the skin, nail dystrophy, oral leukoplakias with a tendency to malignancy degeneration and severe immune deficiency
Dyskeratotis congenita
If resolution of congenital malalignment of the big toenail has not started by age _____, it will likely not occur
2 years
Systematic radiographic examinations of congenital malalignment of the big toe
Lateral deviation of the distal phalanx (hallux valgus interphalangeus)
First described under the name subungual seborrheic keratosis
Longitudinal brownish to dirty-yellow lesion under the nail that shines through the plate
Surgical removal demonstrates an acanthoma histologically made up of mainly basaloid cells
Onychocytic matricoma
Fibroepithelial neoplasm originating from the matrix
At the free end of the nail plate, small holes can be recognized
Onychomatricoma
Arises from the distal matrix
Produces a thread of abnormal keratin
Whitish, ivory-colored, yellowish, reddish, or light-brown band in the nail
End-on dermatoscopy shows a circumscribed thinning of the nail plate over the keratotic distal end
V-shaped onycholysis develops in the distal nail bed
Onychopapilloma
Whitish to yellowish line of 1 to 2 mm that does not widen with time
Short longitudinal fissure at its free margin
Tiny round keratotic tip is seen under the nail
Subungual filamentous tumor
Sausage-like lesions with a keratotic tip
Most arise from under the proximal nail fold
Ungual fibrokeratoma
Multiple ungual fibrokeratomas, so-called _____, are a sign of tuberous sclerosis complex
Koenen tumors
Very common pseudotumors of middle-aged and elderly individuals
Most occur in the proximal nailfold
Myxoid pseudocysts
Best known nail tumor because of its highly characteristic symptoms
Extremely painful digit tip
Violaceous red spot under the nail, from which a reddish line may sometimes extend distally
Glomus tumor
Most frequent malignant neoplasm of the nail
Squamous cell carcinoma
Melanonychia is a feature in dark-skinned persons and association with HPV
56
Treatment of choice for SCC of the nail
Mohs surgery
Very slow growing subungual tumor that clinically presents as a longstanding oozing mass
Onycholemmal carcinoma
Most serious nail condition
Nail melanoma
Brown streaky pigmentation of the nail
Longitudinal melanonychia
Four lesion types that can induce a true LM
Melanocyte activation
Matrix lentigo
Matrix nevus
Melanoma
Regular light-brown band on a gray background
Functional LM
Regular brown band on a brown background
Lentigo
Regular brown band with dark brown spots on brown background
Nevus
Irregular brown band with asymmetric, unevenly space lines of variable length, proximal widening of the band
Melanoma
Most common sites of ungual melanoma
Thumbs
Big toes
Index fingers
Middle fingers
Periungual pigmentation
Represents periungual spread of the in situ component
Hutchinson sign
Indicated rapid growth of ungual melanoma
Proximal widening
Y/N: Ultraviolet exposure is associated with nail melanoma
No - not associated
