17 - 93 - ACTINIC PRURIGO

Question 1

A rare chronic pruritic and excoriated papular or nodular eruption of sun-exposed and, to a lesser extent, nonexposed skin.

Answer 1

Actinic Prurigo

Question 2

first-line therapy for actinic prurigo

Answer 2

Prevention through avoidance of sunlight

Question 3

primary lesion of actinic prurigo

Answer 3

pruritic papule or nodule that occurs singly or in clusters

Question 4

Answer 4

Papules and nodules are often excoriated and crusted, and plaques may assume a lichenified or eczematous appearance (Fig. 93-2).

Question 5

Answer 5

Although primary lesions of AP do not lead to scarring, healed facial lesions may leave dyspigmentation, and scarring can occur secondary to excoriations (Fig. 93-3).

Question 6

most common genetic predisposition to actinic prurigo

Answer 6

patients with HLA-DR4

Specific variants of HLA-DR4 are closely linked to AP, namely, DRB1 ∗ 0407 and DRB1 ∗ 0401

Question 7

Answer 7

Chronic lesions of AP show more acanthosis and hyperkeratosis. Infiltrates of eosinophils may be seen (Fig. 93-4).

Question 8

Answer 8

Histopathologic findings in AP cheilitis tend to be more distinct and specific. Namely, there is a dense nodular lymphoid infiltrate in the lamina propria with formation of lymphoid follicles and expanded germinal centers 11 (Fig. 93-5). Eosinophilic spongiosis is also common. 1

Question 9

Some of the clinical features that suggest a diagnosis of AP rather than PMLE include:

Answer 9

• disease onset in childhood,
• presence of lesions on both exposed and sun-protected skin,
• involvement of lip mucosa and conjunctiva,
• persistence of lesions beyond 4 weeks,
• occurrence in wintertime,
  
  • excoriations, and scarring

Question 10

Question 11

Question 12

Question 13

The treatment of choice in more severe or recalcitrant cases of actinic prurigo

Answer 13

thalidomide

initial doses of 50 to 100 mg daily for children and 100 to 200 mg daily for adults, preferably given intermittently

Question 14

A 15 year-old, male came in with multiple papules and nodules with some excoriations on the forearm, patient claims that it is present all year round but worse during summer.

In relation to the case, All are true except:

A. Improves in adolescence

B. It is more severe when disease begins in childhood

C. UVB is implicated more than UVA

D. There is a concomitant increase in dermal dendrocytes and lymphocytes

Answer 14

C

The case is actinic prurigo. The eruption is often present all year round, but it is commonly worse in summer. P.1628 . UVA is implicated more often than UVB, p.1629

Question 15

This medications seems to be ineffective for actinic prurigo

A. Antihistamine

B. Antimalarial

C. Azathioprine

D. Thalidomide

Answer 15

B

Unlike some of the other photoexacerbated dermatoses, antimalarials seem to be ineffective for AP. P.1632

Question 16

. What is the most serious complication of Thalidomide

A. Thromboembolism

B Teratogenicity

C. Peripheral Neuropathy

D. Seizure

Answer 16

B
The most serious complication associated with thalidomide is terato- genicity, so pregnancy must be rigorously avoided. P.1632

Question 17

what is the treatment of choice in more severe or recalcitrant cases of actinic prurigo

A. Antihistamine

B. Antimalarial

C. Azathioprine

D. Thalidomide

Answer 17

D

The treatment of choice in more severe or recalcitrant cases is thalidomide p. 1632

Question 18

The following supports the diagnosis of actinic prurigo except:

A Increase IgE

B. (+) HLA DR4 DRB1*0401

C. (+) ENA

D. (+) provocation testing w/ solar stimulator

Answer 18

D

Assessment of ANA and ENA should be undertaken to exclude subacute cutaneous or other forms of cutaneous LE. The finding of HLA DR4, type DRB1 ∗ 0401 or DRB1 ∗ 0407 (especially the latter), supports the diagnosis of AP. Patients with moderate or severe presentations of AP may also have elevated serum immunoglobulin E (IgE) levels.

Question 19

UV radiation that is more implicated in actinic prurigo

Answer 19

UVA

Question 20

Clinical course and prognosis of actinic prurigo

Answer 20

When the disease begins in childhood (less than age 20 years), eruptions tend to be more severe and acute but remission in adulthood is more likely.

When disease begins in adulthood, a milder but more persistent course is seen.

Question 21

T/F. Antimalarials are effective in actinic prurigo

Answer 21

False

Unlike some of the other photoexacerbated dermatoses, antimalarials seem to be ineffective for AP

Question 22

cornerstone of management for AP

Answer 22

Sun protection and avoidance strategies