Chap 184: Juvenile Dermatomyositis

Question 1

most common inflammatory myositis in children

Answer 1

juvenile dermatomyositis

Question 2

JDM is distinguished by

Answer 2

proximal muscle weakness and a characteristic rash

Question 3

pathology of JDM

Answer 3

vascular inflammation

Question 4

history of infection in the __ mo before disease onset is usually reported

Answer 4

3 mo

Question 5

incidence of JDM

Answer 5

3 cases/1million children/yr

Question 6

peak age of onset of JDM

Answer 6

4-10yr

Question 7

sex ratio

Answer 7

girl to boys 2:1

Question 8

pathogenesis of JDM

Answer 8

upregualtion of gene products controlled by type 1 IFNs

Question 9

diagnostic criteria of JDM

Answer 9

classic rash plus 3 of the following: weakness, muscle enzyme, EMG changes and muscle biopsy

Question 10

what are the classic rash of JDM

Answer 10

heliotrope rash of the eyelids and gottron papules

Question 11

description of heliotrope rash

Answer 11

blue-violet discoloration of the eyelids that may be associated with periorbital edema

Question 12

difference offacial erythema of JDM and SLE

Answer 12

facial erythema of JDM crosses nasolabial folds

Question 13

bright pink or pale shiny thickened or atrophic plaques over the proximal interphalangeal joints and distal interphalangeal joints and occasionally on the knees, elbow, small joints of the toes and ankle malleoli

Answer 13

gottron papules

Question 14

thickened erythematous and scaly rash over the palms and soles along the flexor tendons

Answer 14

mechanic’s hands

Question 15

what antibodies is associated with mechanics hands

Answer 15

anti-Jo1 antibodies

Question 16

description of weakness of JDM

Answer 16

insidious; symmetric; proximal muscles

Question 17

what expected examination findings for JDM (due to weakness)

Answer 17

inability to perform sit up, head lag in a child after infancy

Question 18

describe as use of hands on thighs to stand from sitting position

Answer 18

Gower sign

Question 19

description of respiratory weakness in JDM

Answer 19

medical emergency; demonstrates hypercarbia rather than hypoxemia

Question 20

indication of muscle biopsy for JDM

Answer 20

diagnosis is in doubt or for grading disease severetiy

Question 21

EMG changes seen in JDM

Answer 21

short, small polyphasic motor unit potentials; positive sharp waves; insertional irritability; bizarre, high frequency repetitive discharges

Question 22

muscle enzymes elevated in JDM

Answer 22

crea kinase; AST; LDH; aldolase

Question 23

children with classic JDM rash but with no weakness or inflammation is called

Answer 23

amyopathic JDM or dermatomyositis sine myositis

Question 24

level of ESR and rheumatoid factor in JDM

Answer 24

norMAL esr; RF negative

Question 25

ANA in JDM

Answer 25

80%

Question 26

maintstay therapy of JDM

Answer 26

corticosteroids (oral if stable without debilitating weakness; high dose methylpred if with severe weakness)

Question 27

steroid sparing agent of JDM

Answer 27

methotrexate

Question 28

secondary disease-modifying agent to reduce rash and maintain remission

Answer 28

hydroxychloroquine

Question 29

mortality rate of JDM

Answer 29

1%

Question 30

7yr ff up

Answer 30

75% of patients have little to no residual

Question 31

complciations of JDM

Answer 31

vascultiis, lipodystrophy and calicinosis