16 - 91 - NAIL DISORDERS

Question 1

no terminal phalanx and no nail growth

Answer 1

Cooks syndrome or atelephalangia with anonychia

Question 2

half-side index fingernail hypoplasia and a Y-shaped radiologic alteration of the distal phalanx is characteristic for what syndrome?

Answer 2

Iso-Kikuchi syndrome

Question 3

Micronychia may be a sign of?

Answer 3

phenytoin and alcohol fetopathy and is a constant feature of congenital onychodysplasia of Iso-Kikuchi (COIF [congenital onychodysplasia of index finger] syndrome)

Question 4

short wide nail, mostly of the thumb, which develops from the age of 12 years on and is the result of a premature ossification of the epiphysis of the distal phalanx

Answer 4

Racket nail

Question 5

may develop in patients under chronic hemodialysis who develop a tertiary hyperparathyroidism with resorption of the bone of the terminal phalanx

Answer 5

Very short nails (brachyonychia)

Question 6

most common color change of the nail

Answer 6

Leukonychia

It is caused by alterations in the keratinization of the nail plate with the nail cells being parakeratotic and/or having an eosinophilic cytoplasm in histologic sections.

Question 7

Muehrcke lines are a pair of 2 whitish transverse lines and are said to be a sign of what?

Answer 7

hypalbuminemia

Question 8

Erythronychia is the term for red nails. It may appear as red spots in the matrix (Fig. 91-6), 2 one or more longitudinal streaks in the distal matrix and nail bed

Multiple red bands are commonly caused by inflammatory conditions such as?

Answer 8

lichen planus

Question 9

single red band may represent specific tumors such as?

Answer 9

onychopapilloma or Bowen disease

Question 10

term for green nails.

Answer 10

Chloronychia

n almost all cases, it is caused by a colonization of the nail by Pseudomonas aeruginosa.

Question 11

treatment of choice of P. aeruginosa colonization

Answer 11

soaking in diluted white vinegar, 2 or 3 times daily for 10 minutes, then brushing the fingers dry.

Household bleach for fingertip baths can be used undiluted or 1:1 diluted in water.

Question 12

Glauconychia is described as discoloration of nail of what color?

This is caused by what?

Answer 12

Blue

Copper sulfate

Question 13

makes the nail jet-black

Answer 13

Silver nitrate

Question 14

Slate-gray to bluish nail matrix is a sign of?

Answer 14

argyria

Question 15

lenticular labial, oral, and genital mucosal brown spots with melanonychias is characteristic for what syndrome?

Answer 15

Laugier-Hunziker-Baran syndrome

Question 16

most frequent sign of nail melanoma

Answer 16

Longitudinal nail pigmentation

Question 17

Hematomas occupying more than how many % of the nail field are commonly associated with a fracture of the distal phalanx?

Answer 17

> 50%

Question 18

narrow red to almost black longitudinal lines in the distal nail bed and are caused by blood that is enclosed in the subungual keratin

Answer 18

Splinter hemorrhages

Question 18

Oblique splinter hemorrhages may be a sign of?

Answer 18

trichinosis

Question 19

Detachment of the nail from the distal nail bed

Answer 19

onycholysis.

Question 20

cause of onycholysis semilunaris

Answer 20

Direct trauma resulting from overzealous nail cleaning

This is characterized by sharply delimited proximal margins that may look like a half moon.

Question 21

exaggeration of nail bed and matrix hyperkeratosis

Answer 21

Onychogryposis

• It consists of innumerable stacks of keratin layers piled up one over the other, grows upward, is opaque and often has the shape of a ram’s horn
• There is usually no contact with the nail bed anymore and the nail pocket is extremely short. It is mainly seen in elderly, neglected, and debilitated individuals

Question 22

bridging of the nail pocket by connective tissue, in most cases scars

Answer 22

Pterygium

It is very common in lichen planus (Fig. 91-20), but is occasionally seen in other conditions, such as bullous pemphigoid, but particularly also after trauma

Question 23

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

Answer 23

PTERYGIUM INVERSUM ## Footnote This is quite common in acral scleroderma and Raynaud syndrome, but also may be idiopathic

Question 24

temporary slowdown or even arrest of nail formation results in a transverse groove that runs parallel to the lunula border

Answer 24

BEAU LINES

Question 25

result of a longer-lasting arrest of nail matrix proliferation that eventually results in a proximal gap in the nail and proximal onycholysis

Answer 25

Onychomadesis

Question 26

give examples of causes of Beau lines

Answer 26

* Repeated Beau lines indicate repeated **trauma**, such as **chemotherapy** cycles. * Equally distributed Beau lines hint at a general cause, whereas one-sided lines are seen after **surgery** of the extremity or a single-digit line at previous finger or toe surgery. * A great many different causes are known, ranging from **high fever** to other serious diseases. * Localized Beau lines and onychomadesis were also seen several weeks after **hand-foot-and-mouth disease (coxcackievirus infection)**. * **Trauma**,** cosmetic manipulations, onychophagia, and onychotillomania** are other causes and explain why the fingernails are predominantly affected

Question 27

small depressions in the nail surface resulting from minute foci of abnormal keratinization in the apical matrix

Answer 27

Pits ## Footnote This produces small mounds of parakeratosis that tend to break away from the nail when this emerges from under the proximal nailfold

Question 28

Large surface defects are typical for pustular psoriasis and are called

Answer 28

elkonyxis

Question 28

differentiate the pits seen from psoriasis vs atopic dermatitis and alopecia areata

Answer 28

Pits are the most frequent sign of nail psoriasis where they are deep and of regular size, whereas those developing in alopecia areata and atopic dermatitis are more shallow and less-well delimited

Question 29

rough nails

Answer 29

Trachyonychia

Question 30

Multiple **longitudinal fissures**, often associated with nail thinning and ridges

Answer 30

onychorrhexis

Question 31

lamellar **splitting** of the nail at its free end

Answer 31

Onychoschizia ## Footnote t is usually confined to fingernails and occurs much more often in women than in men, pointing to the importance of environmental factors, such as frequent water contact that results in hydration and dehydration of the nail, which leaks cementing lipoproteins out.

Question 32

Proximal ingrowing of the nail

Answer 32

retronychia ## Footnote It is caused by a single strong or repeated minor trauma to the nail that eventually results in a backward movement of the nail plate.

Question 33

Overcurvature of the nails

Answer 33

pincer nails ## Footnote The most common variant shows a distally increasing curvature, but it may also remain at the same degree (tile nail) or exhibit sharp lateral bends

Question 33

most common type of ingrown nails

Answer 33

distal–lateral ingrowing of the edge of the big toenail

Question 34

how do pits form on the nails

Answer 34

They are thought to arise from tiny psoriatic lesions in the apical matrix leading to parakeratosis that breaks off leaving these hole-like lesions. ## Footnote When the parakeratosis remains it is seen as an ivory-colored spot in the proximal third of the nail plate

Question 35

Infection with what HPV types is the most common cause for viral warts of the nail unit

Answer 35

HPV types 1, 2, 3, 4, and 7

Question 35

most cases of trachyonychia are caused by what condition?

Answer 35

atopic dermatitis ## Footnote Trachyonychia is the term for rough nails and a hallmark of the so-called 20-nail dystrophy. In author’s experience, most cases are caused by atopic dermatitis, although psoriasis, alopecia areata, and nail lichen planus were also found as the underlying disorder.

Question 36

Question 37

nail lichen planus most frequently affects what part of the nail?

Answer 37

proximal matrix ## Footnote Matrix involvement leads to longitudinal ridging and splitting until the distal nail plate breaks away and a pterygium develops

Question 38

end stage of ungual lichen planus

Answer 38

Postlichen atrophy

Question 39

Muehrcke lines are 2 parallel white bands in the middle of the nail bed that do not move out and are seen in what condition?

Answer 39

severe hypoalbuminemia

Question 40

chewing of the nails

Answer 40

onychophagia

Question 41

picking of the periungual skin

Answer 41

perionychotillomania

Question 42

nails are virtually rubbed away

Answer 42

onychoteiromania

Question 43

nail is pulled out in pieces

Answer 43

onychotillomania

Question 44

cutting device is used to remove all the nail

Answer 44

onychotemnomania ## Footnote frankly psychotic behavior; the patients bite on their nails in the lunula or proximal nail bed region to produce pain

Question 45

has been successfully used in a number of obsessive-compulsive disorders, including autoaggressive nail conditions

Answer 45

N-acetyl cysteine in a dose of 1800 to 2400 mg/day

Question 46

Drug than can cause Permanent nail loss

Answer 46

Bleomycin

Question 47

drug that can cause Granulation tissue formation on the nail

Answer 47

Reverse Transcriptase Inhibitors (indinavir)

Question 48

Question 49

shows 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, and vellus hair cysts

Answer 49

pachyonychia congenita

Question 50

longitudinal brownish to dirty-yellow lesion under the nail that shines through the plate

Answer 50

Onychocytic Matricoma

Question 51

Onychopapilloma arises from what part of the nail

Answer 51

distal matrix

Question 52

* It is a fibroepithelial neoplasm originating from the matrix. The nail is thickened, funnel-shaped, yellow, striated, and may show splinter hemorrhages * Dermatoscopy shows that the tunnels contain capillaries that may run a long distance distally in the nail; in rare cases they remain patent, and may cause bleeding upon nail trimming

Answer 52

Onychomatricoma

Question 53

Multiple ungual fibrokeratomas, so-called Koenen tumors, are a sign of what disease?

Answer 53

tuberous sclerosis

Question 54

Multiple ungual fibrokeratomas are called?

Answer 54

Koenen tumors

Question 55

Patients usually present with the complaint of an extremely painful digit tip. Clinical examination reveals a violaceous red spot under the nail of a finger, from which a reddish line may sometimes extend distally

Answer 55

Glomus Tumor

Question 56

most frequent malignant neoplasm of the nail

Answer 56

SCC

Question 57

Bowen disease may clinically resemble a flat agglomeration of warts. Paronychia may be associated. Melanonychia is a feature in dark-skinned persons and association with what HPV?

Answer 57

HPV56 ## Footnote Other high-risk HPV are HPV16, HPV18, and HPV35, but many more were found, hinting at a possible genitodigital transmission

Question 58

numerical increase in melanin-producing cells

Answer 58

matrix lentigo

Question 58

nest-like agglomeration of melanocytes in the matrix; most are seen in children and are junctional

Answer 58

matrix nevus

Question 59

most common sites of acral melanoma

Answer 59

Thumbs, big toes, index fingers, and middle fingers

Question 60