Ch. 13 - White spots

Question 0

What can cause decreased melanin pigmentation?

Answer 0

• a reduction in the number of melanocytes or

- a decrease in their melanin production

Question 1

What are white spots in the skin a result of?

Answer 1

decreased melanin pigmentation

Question 2

What should white spots be examined for?

Answer 2

1. partial versus complete pigment loss

2. presence or absence of scale

Question 3

White spots are seen more easily by the use of what?

Answer 3

Wood’s light

Question 4

an idiopathic hypopigmentary condition that appears clinically as white patches surmounted by fine, ‘bran-like’ scales.

Answer 4

pityriasis alba

Question 5

Who is pityriasis alba most commonly seen in?

Answer 5

darkly pigmented children

Question 6

pityriasis alba is symptomatic or asymptomatic?

Answer 6

asymptomatic

Question 7

What does pityriasis alba most often present as?

Answer 7

a 1-4 cm white patch with a fine, powdery scale.

Question 8

What is pityriasis alba most often misdiagnosed as?

Answer 8

tinea versicolor

Question 9

the result of melanocyte destruction or suppressed melanin production secondary to inflammation of the skin that appears as a hypopigmented macule.

Answer 9

post-inflammatory hypopigmentation

Question 10

What are causes of post-inflammatory hypopigmentation?

Answer 10

1. physical trauma
2. chemicals
3. skin diseases

Question 11

What are some physical agents that can induce post-inflammatory hypopigmentation?

Answer 11

X-irradiation & frostbite

Question 12

What is the therapy for post-inflammatory hypopigmentation?

Answer 12

none; repigmentation will sometimes occur

Question 13

a superficial fungal infection of the stratum corneum that results in altered pigment in the epidermis, with the lesions appearing as finely scaling patches

Answer 13

tinea versicolor

Question 14

What is the most common color that the epidermis becomes with tinea versicolor?

Answer 14

white

Question 15

T/F:Tinea versicolor is an uncommon disease, affecting only 1% of the general population.

Answer 15

FALSE: (it’s a common disease)

Question 16

Where is the incidence of tinea versicolor higher?

Answer 16

in tropical climates

Question 17

What age group is tinea versicolor most common among?

Answer 17

young adults

Question 18

Tinea versicolor is occasionally associated with ___, but more often is asymptomatic.

Answer 18

mild pruritis

Question 19

What is the appearance of the lesions upon physical examination in patients with tinea versicolor?

Answer 19

round, hypopigmented, slightly scaling patch that often starts as multiple small follicular macules but become confluent.

Question 20

What does the use of a wood light reveal in patients with tinea versicolor?

Answer 20

the scales fluoresces pale yellow or orange (but not universal or should be relied on)

Question 21

Where is the usual distribution of tinea versicolor in patients?

Answer 21

neck, trunk, and upper arms (face & legs involved in tropical climates)

Question 22

In adults, the white spots of tinea versicolor is most often misdiagnosed as _____.

Answer 22

vitiligo

Question 23

Tinea versicolor appearing as pink or tan scaling patches on the chest may be misdiagnosed as _____.

Answer 23

seborrheic dermatitis

Question 24

What is the only examination that works to diagnose tinea versicolor?

Answer 24

KOH preparation

Question 25

Which skin disorder gives the appearance of spaghetti & meatballs upon KOH preparation?

Answer 25

tinea versicolor

Question 26

What is the simplest most effective therapy for tinea versicolor?

Answer 26

oral fluconazole

Question 27

After initial therapy, how long does it take for the white spots to retain pigment?

Answer 27

months

Question 28

What is tinea versicolor caused by?

Answer 28

infection with the fungus Malassezia

Question 29

a rare, autosomal dominantly inherited, neurocutaneous disorder with several skin manifestations, including macules, caused by mutations in one of two genes, tsc1 & tsc2.

Answer 29

tuberous sclerosis

Question 30

What is the classic triad of tuberous sclerosis?

Answer 30

seizures, mental retardation, and adenoma sebaceum

Question 31

a misnamed disorder consisting of angiofibromas that begin in childhood and appear clinically as red papules on the face.

Answer 31

adenoma sebaceum

Question 32

In which skin disorder do the white spots appear as a thumbprint or ash leaf - oval at one end and pointed at the other?

Answer 32

tuberous sclerosis

Question 33

Where are the white spots of tuberous sclerosis most often found?

Answer 33

on the trunk and less often the face and extremities

Question 34

T/F: All infants with a seizure disorder should be screened for white spots with a Wood's light examination.

Answer 34

TRUE

Question 35

an acquired condition in which functional melanocytes disappear from affected skin; lesions clinically appear as totally white, non-scaling, sharply demarcated macules.

Answer 35

vitiligo

Question 36

Higher incidence rates of vitiligo occurs in what population?

Answer 36

dark-skinned individuals within the 10-30 yr. age group

Question 37

Vitiligo is usually asymptomatic/symptomatic?

Answer 37

asymptomatic

Question 38

What is the primary lesion of vitiligo present as upon physical examination?

Answer 38

a white macule that is usually totally depigmented

Question 39

T/F: scale is present with vitiligo

Answer 39

FALSE (NO scaling)

Question 40

Where are the most common areas affected by vitiligo?

Answer 40

the extensor bony surfaces (backs of hands, elbows, and knees) and the periorificial areas (around the mouth, eyes, rectum, and genitalia)

Question 41

T/F: the laboratory is not helpful for diagnosing vitiligo?

Answer 41

TRUE

Question 42

T/F: There is no cure for vitiligo?

Answer 42

TRUE

Question 43

What is the initial therapy for vitiligo?

Answer 43

narrow-band UVB or topical steroids

Question 44

What cells are absent in patients with vitiligo?

Answer 44

melanocytes

Question 45

What are 3 proposed pathologic mechanisms for vitiligo?

Answer 45

1. autoimmune 2. neural 3. self-destruction

Question 46

What is the most common type of cutaneous T-cell lymphoma?

Answer 46

Hypopigmented Mycosis Fungoides

Question 47

Where do skin lesions occur in patients with hypopigmentated mycosis fungoides?

Answer 47

the buttocks and trunk and can evolve into plaques or tumors

Question 48

A common condition in women that is under-recognized where lesions appears as well demarcated, small macules, like 'sprinkled confetti'.

Answer 48

idiopathic guttate hypomelanosis

Question 49

Where does idiopathic guttate hypomelanosis most commonly appear on the body?

Answer 49

the shins, but may also be found on the forearms

Question 50

What skin disorder is caused by the acid-fast organism Mycobacterium leprae?

Answer 50

Leprosy

Question 51

Where is leprosy endemic?

Answer 51

south-eastern USA & Hawaii

Question 52

What is the earliest sign of leprosy?

Answer 52

a solitary hypopigmented macule

Question 53

What is the earliest sensory change with leprosy?

Answer 53

loss of feeling to light touch and cold in the hands and feet.

Question 54

Which stain is used to confirm a diagnosis of leprosy?

Answer 54

Fite stain