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162 Cards in this Set

  • Front
  • Back
nail unit anatomy
Embryologic development of the nail apparatus.
nail apparatus
Onychomadesis after an episode of acute paronychia
Nail pitting due to psoriasis.
Trachyonychia (twenty-nail dystrophy). The nails seem sandpapered in a longitudinal direction
Longitudinal melanonychia due to a congenital melanocytic nevus of the nail matrix. The pigmentation involves approximately 75% of the nail plate and the color varies from light brown to black
Congenital malalignment of the great toenails. The longitudinal axis of the nail plate is deviated laterally. There is also onychomadesis of both great toenails and mild nail thickening with lateral ingrowing of the right great toenail.
Nail hypoplasia in nail–patella syndrome. There is hypoplasia of the nails of the first and second digits. This gradient of severity of nail involvement is characteristic
Darier disease. Alternating longitudinal red and white streaks with wedge-shaped subungual hyperkeratosis, V-shaped notching of the distal margin, and fissuring. *G
Nail psoriasis. The nails show salmon patches (“oil drop” changes) and onycholysis with an erythematous border
Acrodermatitis continua of Hallopeau. Recurrent pustular eruption of the nail bed and distal finger.
Nail lichen planus. Note the nail thinning with longitudinal ridging and fissuring
Yellow nail syndrome. Note the overcurvature of the nail and loss of the cuticle, in addition to the yellow discoloration.
Muehrcke’s nails. There are multiple parallel transverse white bands. The curvature matches that of the lunula......seen in nephrotic syndrome and low albumin states
Multiple periungual pyogenic granulomas in a patient taking indinavir
Acute paronychia. In addition to the erythema and purulent discharge, there is significant tenderness.
Median canaliform dystrophy (of Heller)
Subungual exostosis
Correlation of nail findings with anatomic site of nail damage
Myxoid cyst. The longitudinal nail groove is a result of the compression of the nail matrix by the cyst.
Onychomatricoma. The nail is thickened and overcurved with longitudinal yellow streaks. The distal border shows several holes
Bowen’s disease. The lateral portion of the nail plate is absent. The nail bed shows hyperkeratosis with scaling and fissuring of the epithelium
Amelanotic melanoma. Note the diffuse nail destruction and ulceration
ABCDEF rule for clinical suspicion of nail melanoma
What layers is the nail plate made of?
1. outer dorsal plate
2. intermediate plate (multiple desmosomes)
3. ventral plate (high content of soft keratins)
What is the growth rate for fingernails?*G
2-3mm/mo.....6mo needed for total replacement
What is the growth rate for toenails?*G
1mm/mo.....12-18mo for total replacement
what do we call the thin white transverse line at the free edge of the nail plate?
onychocorneal band
What does the proximal nail matrix form?
-dorsal plate
What does the distal matrix (lunula) form?
intermediate and ventral plate
Where are the melanocytes associated with the nail?
in the distal nail matrix and suprabasal layers......think melanocytes should be farther from the body
In someone with light skin, what do you do if there is nail plate pigment?
requires bx, cause their melanocytes sould be dormant and contain pre and stage I/II melanosomes, NOT mature melanosomes
Which keratins are found in the proximal nail matrix?
soft keratins (1, 5, 6, 10, 14, 16, 17)
Which keratins are found in the distal nail matrix?
soft keratins (1,5,10,14,20)
hard keratins (31)
which Ag medites nail plate attachment to the nail bed?
What infection can occur with nail infections?
OM (high risk)....cause collagen fibers in the dermis radiate into the distal phalangeal bone
Where do we see AV anastomoses?
everywhere except the proximal nail fold
What is the underlying abnormality with Beau's lines?
abnormal matrix function...there is interruption of mitotic activity of the proximal nail matrix
What does depth of the beau's line mean? What about width?
Depth: extent of damage....same level in multiple digits suggests systemic disease
Width: duration of damage
What is the most common cause of Beau's lines?
trauma is MC

chronic paronychia
derm dz that affect proximal nail fold
What is the underlying abnormality in onychomadesis?
-there is complete arrest of nail matrix activity -resulting in proximal detachment from proximal nail fold
What is the underlying abnormality in nail pitting?
-proximal nail matrix damage
-it results in foci of abnormal keratiniziation with clusters of parakeratosis that falls off the dorsal nail plate
What do we call longitudinal ridging, fissuring and thinning of nail plate?

can be associated with LP, or a normal part of aging.
What do we call sandpapered nails? And what is the pathophys?
trachyonychia....due to proximal nail matrix damage
What is the pathophys behind true leukonychia?
there is white opaque discoloration due to abnormal nail matrix (distal) keratinization with resultant parakeratotic cells in the ventral nail plate
Who gets punctate leukonychia?
kids, likely due to trauma
Who gets striate leukonychia? And what are common causes
AKA Mee's lines
-adults, commonly women
-can be secondary to trauma from manicures or from shoes
-arsenic or thallium poisoning
-chemotherapeutic agents
What do we call spoon shaped nails (concave)?
What causes koikonychia?
-physiologic in the toenails of kids
-can be occupational or "iron def" in adults
-thyroid abnormalities
What are causes of photo-onycholysis?
What do we call nail plate thickening due to subungal hyperkeratosis?
-it is a nail bed problem
What are common causes of onychauxis?
What is apparent leukonychia?
white discoloration of the nails that fades with pressure because it is due to nail bed edema, not a nail plate issue
What are causes of apparent leukonychia?
-chemo agents
-systemic disease (hypoalbuminemia)
What is the cause of splinter hemorrhages?
damage to longitudinally oriented nail bed capillaries
What causes green nail syndrome?
the greenish black/blue discoloration is due to Pyocyanin produced by pseduomonas
What's the most common cause of ingrown toenails?
congenital malalignment of the big toenails (lateral deviation of the nail plate)
What do we call short, broad thumbnails due to shortening of the distal phalynx?
raquet thumbs (brachyonychia)....AD inheritance
What are the features of Nail-Patella Syndrome (Hereditary osteo-onychodysplasia)?
-absent or hypoplastic nails
-triangle shaped lunulae
-bony abnormalities (absent or hypoplastic patellae, radial head dysplasia and iliac cres exostoses/horns)
How can you confirm the dx of nail-patella syndrome?
iliac horns on pelvic xray in kids
What is the mutation in nail patella syndrome? codes for a transcription factor that regulates collagen synthesis
What changes are seen in the nails of those with EB?
-repeated blisters produce onycholysis with shortening/thickening of the nail (due to nail bed scarring)
-nail matrix involvement results in nail thinning, atrophy, pterygium
What nail changes are seen with pachyonychia congenita?
-thickened and extremely hard nails with increased transverse curvature due to severe nail bed hyperkeratosis

Associated findings: palmoplantar keratoderma, follicular hyperkeratosis
What are the mutations in type I pachyonychia congenita?
KRT6a and KRT16
What are the mutations in type II pachyonychia congenita?
KRT6b and KRT17
Which type of pachyonychia is associated with oral leukokeratosis?
type I
Which type of pachyonychia is associated with premature dentition and pilosebaceous cysts?
type II
What nail changes are seen in Darier Disease?
-multiple red and white longitudinal streaks within the nail plate with MNG cells in the nail bed epithelium
-distal wedge shaped subungal hyperkeratosis plus fissuring corresponding to the bands
-V shaped indentation of the distal margin
-single red band (longitudinal erythronychia) due to benign subungal tumor (onychopapilloma)

*nail changes don't improve with oral retinoids
*similar nail changes in Hailey Haiely
What is the ddx for red lunula?
-alopecia areata
-medial disease (cardiac, COPD, cirrhosis)
-drugs and toxins (imuran, radiation, prednisone, CO2/**CO poisoning)
What are the diagnostic nail changes seen with psoriasis?
-irregular pitting
-salmon patches (oil drop)
-onycholysis with erythematous border
How can we treat psoriatic nail changes?
-IL kenalog
-oral acitretin
What are the nail changes seen in acrodermatitis continua of Hallopeau?
-pustules involving the nail bed and periungal skin
-fingernails most commonly affected

*seen in those with palmoplantar psoriasis
What are the nail changes seen in parakeratosis pustulosa and who gets them?
-seen exclusively in kids
-usually one fingernail, often one side of the nail
-there is subungal hyperkeratosis and onycholysis, this is preceded by erythema, scaling and vesicles of the fingertip
What are the nail changes with LP?
-**dorsal pterygium
-can have 20 nail disease
What does pterygium in nail LP indicate?
How to treat nail LP?
-IL kenalog (when few nails involved)
-systemic steroids to avoid pterygium
What are causes of 20 nail dystrophy (trachyonychia)?
-alopecia areata (seen in 12% of kids vs. 3% of adults)
-psoriasis, eczema
-idiopathic (uncommon and almost exclusively in kids)
What nail findings are seen with alopecia areata?
-geometric pitting
-trachyonychia....more common in kids and seen in those with totalis/universalis
-other findings:erythema of lunula, punctate leukonychia, onychomadesis
What nail changes are seen in eczema?
-Acutely: vesicles/erythema of the proximal nail fold and hyponychium, irregular pits, Beau's lines
-Chronically: localized to hyponychium, subungal hyperkeratosis, onycholysis, fissuring of hyponychium
What is the lovibond angle? And in what disease is it widened?
-formed by the proximal nail fold and the nail plate
-widened in clubbing

Normal= 160, in clubbing it is 180
What is yellow nail syndrome?
-arrested linear nail growth resulting in transverse thickening and overcurving longitudinally
-cuticle is absent
-onycholysis and nail shedding is often seen
What systemic conditions are associated with yellow nail syndrome?
-resp tract involvement (chronic bronchitis, pleural effusions)
How to treat yellow nail syndrome?
Vit D
itraconazole (can accelerate growth)
What's the most common tumor that metastasizes to fingers?
What's the most common tumor that metastasizes to toes?
GU neoplasms
What can transient peripheral nerve injury cause at the level of the nails?
-pseudopyogenic granulomas of the proximal nail fold
-often seen after cast immobilization
-resolves over wks
What is ventral pterygium a sign of?
scleroderma, related to impaired peripheral perfusion (the distal nail plate adheres to the hyponychium)
What are nail changes seen with HIV infection?
-proximal subungal onychomycosis due to T. rubrum
-candida onychomycosis (which indicates immunosuppression)
-chronic periungal warts
If an HIV+ patient has chronic periungal warts, what is the next step in management?
biopsy to rule out SCC....HPV types 16 and 35 have been detected in such lesions
What studies are mandatory with acute paronychia and what is usually found?
-viral/bacterial cultures
-commonly S. aureus or Strep pyogenes
-can also be recurrent herpetic whitlow
What is a good tx for warts around the nail?
IL candida, trichophyton or mumps skin test Ag
What is onychoschizia?
-dehydration of the nail plate often due to frequent hand washing (the wet/dry cycles)
-there is splitting of the distal nail plate into multiple horizontal layers
What secondary infections can be seen with chronic paronychia?
candida or pseudomonas or TB
What is onychotillomania?
-aka habit tic deformity/chronic nail picking
-cuticle absent and proximal nail fold inflamed
-there is a longitudinal central depression
What is another name for onychogryphosis? And who gets it?
-ram's horn nails
-seen in elderly due to chronic trauma and impaired circulation/innervation
What test is done with pincer nails?
xray to exclude subungal is needed if this is present

-pain can be very severe
How do we treat pincer nails?
lateral matricectomy
What is the formal name for ingrown toenail?
What are causes of periungal/subungal pyogenic granulomas?
-penetrating trauma (including piercings)
-ingrown toenails
-systemic retinoids
-EGFR inhibitors
What do we call pink or skin colored papules originating from the proximal nail fold?
fibromas/fibrokeratomas....aka Koenen tumor, seen in 50% of those with tuberous sclerosis

-they CAN produce a nail furrow
What is the most common benign bony proliferation associated with nail abnormalities?
subungal exostosis, most common is on the hallux
-it is a subungal nodule that elevates the nail plate
-confirm with xray
What is the most common nail tumor?
myxoid cysts (mucous cysts)
What is a frequent association with myxoid cysts?
Osteo arthritis of the DIP due to connection to DIP via a tract
Patient has a tender red/bluish nail bed macule visible through the transparent nail plate, what is is?*G
glomus tumor
Patient has localized thickening of the nail plate with perforations consisting of multiple longitudinal hollows, what is the dx?
-there can be multiple splinter hemorrhages
-frontal view shows holes in the thickened free margin
What changes to the nail can be seen with melanocytic nevi of the nail matrix?
longitudinal melonychia
What factors can predispose to Bowen's disease of the nail?
HPV 16
chronic Xray exposure
What is a complication of subungal keratoacanthoma?
-deep invasion with bone destruction
-does not regress spontaneously like cutaneous KA
What is the most frequent malignant tumor of the nail apparatus?
What is the ABCDEF RULE related to nail MM?
o Age (5-7th decade), African-Americans, Asians, and Native Americans (1/3 of nail MM)
o Brown to black, Breadth (3mm or wider), variegated Borders
o Change in nail band Color or size, lack of change in nail morphology despite presumed adequate treatment
o Digit most commonly involved (thumb and hallux)
o Extension of pigment into proximal or lateral nailfold (Hutchinson’s sign)
o Family or personal history of DN or MM
Patient has a smooth soft nodule adjacent to the DIP. If at the proximal nail fold, it can cause longitudinal gooving int he nail plate. It contains clear yellow viscous fluid. What is the dx?*G
myxoid cyst
How do we distinguish acquired digital fibrokeratoma from accessory digit on path?*G
ADF does NOT have nerves while AD does have prominent nerve fasicles
What are some causes of absent lunula?*G
yellow nail syndrome
multiple myeloma
What is the formal name for short nails?*G
What is the mutation in Darier's?*G
SERCA2, a Ca ATPase
What is the formal name for long nails?*G
-seen in Marfan's or Ehler's Danlos
What is elkonyxis?*G
large 2-3m pits
How to distinguish habit tic from Heller median canaliform dystrophy?
Habit tic: horizontal parallel ridges
Heller: christmas tree pattern to lines
What is a heloma?
What are lindsay's nails? And in what condition is it seen?*G
distal nail is normal while proximal nail is white....seen in chronic renal failure.

*half and half cause you have 2 kidneys
What is onychia?
inflammation of the nail unit
what is onychoclavus?
subungal corn
what is onychocryptosis?
ingrown nail +/- exuberant granulation tissue, usually in the first toe
What are causes of onychomadesis?
-systemic disease
-PCN allergy
-drugs (chemo agents, carbamazepime, lithium)
What is onychophagia?
nail biting
what is onychoptosis?
nail loss
What are plummer's nails?
distal onycholysis secondary to hypothyroidism
What are Terry's nails?
all but distal 2mm evenly white, caused by problem in nail bed.
Caused by *cirrhosis, congenital heart failure, DM

""the liver is big so Terry's takes up most of the nail plate.
What meds can cause yellow nail syndrome?
What is the most common organism in distal subungal onychomycosis?*G
T rubrum
What is the most common organism in white superficial/proximal subungal onychomycosis?*G
T rubrum (HIV pts and kids)
What is the most common organism in superficial onychomycosis?*G
T mentag
What is the most common organism in lateral invasion + paronychia onychomycosis?*G
hendersonula toruloidea
scatylidium hyalinum
mooshi is fluffy
what factors affect nail growth?
accelerated: youth, daytime, summer, pregnancy, hyperthyroidism, psoriasis, PRP, itraconazole
Reduced: elderly, nightime, winter, fever, malnutrition, onychomycosis
what type of epithelium is seen with the nail matrix?
keratinizing epithelium, NO granular layer
what part of the nail has a higher risk of osteomyelitis?
the proximal nail matrix, it has diminished immune regulation similar to the hair follicle
what causes splinter hemorrhages from a anatomic perspective?
damage to the longitudinal capillaries in the dermis of the nail
what are glomus bodies?
encapsulated oval structures with tortuous vessels, nerves, and a capsule formed by cholinergic muscle cells and cholinergic nerves

*they dilate with cold to maintain digital blood supply
*they are found mostly in the dermis beneath the nail bed
in what diseases do you see nail pitting?
what is elkonyxis?
large 2mm pits in the nail
what is hapalonychia?
soft nail plate
who can get trachyonychia?
those with:
what causes diffuse leukonychia?
white superficial onychomycosis
congenital disease
what causes distal splinter hemorrhages?
fungus, psoriasis, trauma
what causes proximal splinter hemorrhages?
trichinosis, vasculitis, carditis
what genoderm has melonychia?
laugier hunziker
what do we call the nail finding of ridges that arise from the proximal nail fold and converge in a V shaped pattern distally?
Chevron or Herringbone nail
in what diseases can you see dorsal pterygium?
cicatricial pemphigoid
which genoderm has brachyonychia?
Rubenstein Taybi
which conditions have absent lunulae?
yellow nail syndrome and renal failure
what causes Muehrcke's nails?
hypoalbuminemia (nephrotic syndrome)
-you get transverse white bands
In what disease do you see reduced capillary density with avascular areas alternating with dilated capillary loops in the cuticle?
DM And scleroderma
which chemo agents cause apparant leukonychia (Muercke's)?
which meds can cause melonychia?
-chemoagents (doxorubicin, daunorubicin, 5-FU)
-zidovudine (AZT)
which meds have been indicated in ischemic changes of the nail/fingers?
beta blockers
what is platyonychia?
flat nail (can be inherited or acquired)
patient has a tumor of the nail which is aggrevated by physical and thermal stimuli (cold eesp), dx?
glomus tumor
what gives rise to the glomus tumor?
the neuromyoarterial glomus cells of the nail bed dermis
what causes blue lunulae?
what is median canaliform dystrophy?
inverted fir tree (idiopathic or inherited)