juvenile dermatomyositis

1. JUVENILE DERMATOMYOSITIS
PRESENTER : DR PRAKASH MAN SHAH
MODERATORS: DR SHANKAR YADAV
DR MUKESH BHATTA
DR SUBASH BASNET
DR LALAN RAUNIYAR

2. CASE SCENARIO
• 11 year old girl presented to pediatric clinic with
C/o :
• Insidious onset muscle weakness and pain of lower limbs for 3 months
• Limiting the activities as getting up from chair, climbing stair
• Fever, dysphasia, dysphonia
• Peri-orbital rash and swelling
• No H/O joint pain, joint stiffness, hair loss

3. On Physical Examination:
• Temperature : 40.1 C
• Pallor + , few palpable nodes in the neck
• Heliotropic rash above both upper eyelids
• MSK : Minimal tenderness of the thigh and proximal arm muscles with marked
difficulty in raising arm muscles above the head
Differential Diagnosis: ???

4. • Systemic Lupus Erythematosus
• Muscle Dystrophy
• Dermatomyositis
• Juvenile idiopathic arthritis
• Metabolic myopathies

5. OUTLINE
• Epidemiology
• Pathogenesis
• Clinical Features
• Diagnostic Criteria
• Investigations
• Treatment
• Follow up

6. EPIDEMIOLOGY
• 3·2 per million children per year
• average age at onset : 7 years
• < 4 years at onset : 25 %
• Male : female  2·3 : 1
• In a study of 12 children with JDM from North India, female to male ratio was
2:1.4
Brian M Feldman, Lisa G Rider, Ann M
Reed, Lauren M Pachman, Lancet 2008
S Singh et al. Indian Pediatrics 1997,March

7. ETIOLOGY
• Result from environmental triggers in the setting of an underlying genetic
susceptibility
• Specific HLA alleles, such as B8, DRB1*0301, DQA1*0501, and DQA1*0301
• Cytokine polymorphisms
• (TNFα)–308A promoter polymorphism
• intronic polymorphisms of the interleukin-1 receptor antagonist

8. PATHOGENESIS
Brian M Feldman, Lisa G Rider et al.

9. PATHOGENESIS
• Typical vasculopathy changes
• loss of capillaries (capillary dropout)
• Perivascular inflammation
• Small vessel angiopathy
• Deposition of immune complexes and anti endothelial antibodies  endothelial
damage
Wienke et al. December 2018,vol.9,article 2951

10. CLINICAL FEATURES
• Constitutional
• Fever: 16–65%
• Lymphadenopathy: 20%
• Lethargy: 10%
• Pulmonary
• Dyspnea: 7–43%
• Gastrointestinal
• Dysphonia or dysphagia: 18–44%
• Gastrointestinal symptoms: 22–
37%
• Musculoskeletal
• Weakness: 95%
• Myalgia or arthralgia: 25–73%
• Arthritis: 23–58%
• Contractures: 26–27%
• Raynaud’s disease: 9–14%

11. Cutaneous
• Heliotrope rash: 66–100%
• Gottron’s papules: 57–100%
• Nailfold capillary changes: 91%
• Malar or facial rash: 42–73%
• Mouth ulcers: 35%
• Skin ulcers: 23–30%
• Limb oedema: 11–32%
• Calcinosis: 6–30%
• Lipodystrophy: 10–14%

12. HELIOTROPE RASHES

13. GOTTRON PAPULES

14. SHAWL SIGN / MECHANIC HAND

15. changes in the nail fold capillaries (91%)  tortuosity, dilatation, and
dropout
Periungual telangiectasia

16. SKIN ULCERATIONS
• serious and potentially life-threatening manifestation

17. MUSCLE WEAKNESS

18. LIPODYSTROPHY AND CALCINOSIS

19. EULAR/ACR classification criteria
Variable Score points
Without
muscle
biopsy
With
muscle
biopsy
Age of onset
Age of onset of first symptom assumed to be related to the
disease ≥18 years and <40 years
1.3 1.5
Age of onset of first symptom assumed to be related to the
disease ≥40 years
2.1 2.2
Muscle weakness
Objective symmetric weakness, usually progressive of the
proximal upper extremities
0.8 0.5
Objective symmetric weakness, usually progressive of the
proximal lower extremities
1.9 1.6

20. Neck flexors are relatively weaker than neck extensors 1.9 1.6
In the legs, proximal muscles are relatively weaker than
distal muscles
0.9 1.2
Skin manifestations
Heliotrope rash 3.1 3.2
Gottron papules 2.1 2.7
Gottron sign 3.3 3.7
Other clinical manifestations
Dysphagia or esophageal dysmotility 0.7 0.6

21. Laboratory measurements
Anti-Jo-1 (anti-histidyl-tRNA synthetase) autoantibody
present
3.9 3.8
Elevated serum levels of CK or LDH or AST or ALT 1.3 1.4
Muscle biopsy features—presence of:
Endomysial infiltration of mononuclear cells
surrounding but not invading myofibers
1.7
Perimysial and/or perivascular infiltration of
mononuclear cells
1.2
Perifascicular atrophy 1.9
Rimmed vacuoles 3.1

22. • EULAR/ACR criteria include
• four variables related to muscle weakness
• three related to skin manifestations
• laboratory measurements
• other clinical manifestations
• The EULAR/ACR score in the absence of a muscle biopsy is interpreted as
• Definite – Score of ≥7.5
• Probable – Score of ≥5.5 to <7.5
• Possible – Score of 5.3 or 5.4
EULAR and ACR classification criteria, UpToDate

23. LABORATORY FINDINGS
• Elevated Muscle-enzyme levels
• Creatine kinase
• Aldolase
• Aspartate Aminotransferase
• Alanine aminotransferase
• Lactate Dehydrogenase
• Erythrocyte Sedimentation Rate – Increased
• Rheumatoid factor – Negative
• Antinuclear antibody( ANA) – Positive in >80%

24. • Myositis – associated antibodies (MAAs) : not specific
●SSA ●SSB ●Double-stranded (ds) DNA
● Sm ●Ribonucleoprotein
• Myositis – specific antibodies (MSAs) : specific
● Anti – Jo – 1 ● Anti – Mi – 2
● Anti – p155/140 ● Anti – NXP2
● Other myositis – specific autoantibodies
SEROLOGIC TESTING RESULTS

25. MRI
Rheumatology, Volume 50, Issue 12, December 2011, Pages 2237–
2244

26. ELECTROMYOGRAPHY
The Lecturio Medical Concept Library

27. BARIUM SWALLOW
The Journal of Pediatrics, Volume 135, Issue 3, September 1999, Pages

28. PULMONARY FUNCTION TEST
Pulmonary outcome in juvenile dermatomyositis: a case-control study, Annals of
rheumatic diseases, 70(1), 86-91

29. HISTOPATHOLOGY

30. DIFFERENTIAL DIAGNOSIS
• Weakness alone
• Motor neuron disease : Spinal Muscular Atrophy
Muscular dystrophies Limb-girdle dystrophies, dystrophinopathies,
facioscapulohumeral dystrophy
Metabolic myopathies Glycogen-storage diseases, lipid-storage disorders,
Endocrine myopathies Hypothyroidism, hyperthyroidism
Drug-induced myopathy Statins, glucocorticoids, hydroxychloroquine, diuretics,
amphotericin B
Neuromuscular
transmission disorders
Myasthenia gravis

31. Weakness with or without rash
Viral Enterovirus, influenza, coxsackievirus, echovirus,
parvovirus, poliovirus
Bacterial and parasitic organisms Staphylococcus, streptococcus, toxoplasmosis,
trichinosis, Lyme borreliosis
Other rheumatic conditions Systemic lupus erythematosus
juvenile idiopathic arthritis
Rash without weakness Psoriasis, eczema, allergy

32. TREATMENT
• First Line
• Prednisolone / Methylprednisolone
• Methotrexate
• Additional treatment options
• IVIG
• Azathioprine
• Cyclosporine A
• Cyclophosphamide
• Tacrolimus
• Mycophenolate Mofetil
• Adjunctive therapies:
• Physical therapy
• Sun protection
• Calcium / Vitamin D

33. At time of diagnosis and at disease flare: Start high dose corticosteroids (preferably methylprednisolone pulse
15-30 mg/kg/dose on 3 consecutive days), followed by oral prednisolone 1-2 mg/kg/day Combine with MTX 15-
20 mg/m2 weekly, preferably sc. Advise sun protection and adequate calcium / vitamin D intake.
Evidence of severe disease?*
NO
Regular reviews - including assessment of muscle
strength, skin disease, major organ involvement, &
patient / parent reported outcome measures
Improvement
NO YES

34. NO YES
Check adherence
and tolerance to
treatment
Continue MTX Wean steroids Intolerance: change
to other DMARD,
such as MMF or
Cyclosporin A
Consider stopping
MTX when disease
in remission for a
minimum of 1 year
off steroids
Intensity treatment by adding IVIG,
or adding or changing to other
medications which may include
cyclosporin A, MMF or a biologic
(rituximab, infliximab or
adalimumab)
Regular reviews - including assessment of muscle
strength, skin disease, major organ involvement, &
patient , parent reported outcome measures

35. Improvement
NO or new calcinosis YES
Intensity treatment
Continue MTX/MMF
or cyclosporin A
Wean steroids Stop added
medication when
well and steroids
weaned
Consider stopping
MTX/MMF or
ciclosporin A when
disease in remission
for a minimum of 1
year off steroids
Consensus-based recommendations for management of juvenile
dermatomyositis, Annals of Rheumatic disease

36. At time of diagnosis and at disease flare: Start high dose corticosteroids (preferably methylprednisolone pulse
15-30 mg/kg/dose on 3 consecutive days), followed by oral prednisolone 1-2 mg/kg/day Combine with MTX 15-
20 mg/m2 weekly, preferably sc. Advise sun protection and adequate calcium / vitamin D intake.
Evidence of severe disease?*
YES
Consider adding or change to Cyclophosphamide 500-
1000g/m2 iv monthly for 3-6 months (or longer if
needed) - alternatively intensify treatment using
other options
Improvement
NO YES
Regular reviews - including assessment of muscle
strength, skin disease, major organ involvement, &
patient / parent reported outcome measures

37. NO YES
Regular reviews - including
assessment of muscle strength,
skin disease, major organ
involvement, & patient / parent
reported outcome measures
Continue MTX Wean steroids Consider stopping
cyclophosphamide
or changing to an
alternative DMARD
Consider stopping
MTX when disease
in remission for a
minimum of 1 year
off steroids
Intensity treatment by adding
rituximab or changing to anti-TNF
(infliximab ) adalimumab) or using
combination therapy with high
dose MTX, Cyclosporin A and IVIG
Improvement ?
NO
YES
Slowly reduce / stop
medication when disease
in remission for a
minimum of 1 year off
steroids
Check adherence and
tolerance to treatment
Consensus-based recommendations for management of
juvenile dermatomyositis, Annals of Rheumatic disease

38. Stringer, et al: Treatment of JDM

39. EVALUATION OF RESPONSE TO THERAPY
• Normalization of elevated serum muscle enzymes
• Increased muscle strength both by history and objective measures,
such as the Childhood Myositis Assessment Scale (CMAS)
• Resolution of skin rash
• Improvement in nailfold capillary changes
UpToDate

40. COMPLICATIONS
• Muscle atrophy, cutaneous
calcifications and scarring or
atrophy
• Aspiration Pneumonia and
Respiratory Failure
• Bowel wall vasculitis and lead to
ischemia, perforation
• Lipodystrophy
• Prolonged corticosteroid
therapy complications
• Arrhythmias ( rare )
Nelson textbook of pediatrics, 21st edition

41. PROGNOSIS
• The mortality rate in JDM has decreased since the advent of
corticosteroids, from 33% to currently approximately 1%.
• At 7 yr of follow-up, 75% of patients have little to no residual
disability,
• 25% continue to have chronic weakness and 40% have chronic rash.
• Up to one-third may need long-term medications to control their
disease.
Nelson textbook of pediatrics, 21st edition

42. DISCUSSION

43. CASE SCENARIO
• 11 year old girl presented to pediatric clinic with
• C/o :
• Insidious onset muscle weakness and pain for 3 months
• Principally affecting the proximal muscles of both arms and legs
• Limiting the activities as getting up from chair, climbing stair
• Fever, dysphasia, dysphonia
• Peri-orbital rash and swelling
• No H/O joint pain, joint stiffness, hair loss

44. On Physical Examination:
• Temperature : 40.1 C
• Pallor + , few palpable nodes in the neck
• Heliotropic rash above both upper eyelids
• MSK : Minimal tenderness of the thigh and proximal arm muscles with marked
difficulty in raising arm muscles above the head

45. How to investigate
• Hematocrit
• Total leucocyte count
• ESR
• Liver Enzymes
• Muscle Enzymes
• Serology
• EMG
• Muscle biopsy

46. Treatment
• Corticosteroids?
• Whether Oral or IV Pulse?
• Reason?

47. Identify the rash

48. CONCLUSION
• JDM though rare should always be considered in the differential diagnosis of any
child with skin rash and muscle weakness
• Vasculopathy due to loss and dysfunction of endothelial cells as a result
inflammatory process is underlying pathology
• Early recognition and aggressive immunosuppressive treatment have improved
prognosis

49. References
• Nelson textbook of pediatrics 21st edition
• Brian M Feldman, Lisa G Rider et al.
• A Bohan et al. N Engl J Med 1975
• UpToDate
• Consensus-based recommendations for management of juvenile
dermatomyositis, Annals of Rheumatic disease

50. THANK YOU