1.gif (1892 bytes)

Brief Reports

Indian Pediatrics 2002; 39:931-935 

Outcome in Juvenile Dermatomyositis


Vaidehi Chowdhary, Anupam Wakhlu, Amita Agarwal and Ramnath Misra

From the Department of Clinical Immunology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Rae Barielly Road, Lucknow.

Correspondence to: Dr. R.N. Misra, Department of Clinical Immunology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Rae Barielly Road, Lucknow. E-mail: [email protected]

Manuscript received: October 31, 2001; Initial review completed: November 15, 2001;

Revision accepted: March 20, 2002.

 

The clinical features, outcome and complications of juvenile dermatomyositis were studied in a tertiary care hospital by retrospective analysis of case records. Nineteen patients were treated over an 11-year period. Median age at diagnosis was 12 years (2.5-16 years). Median duration of disease prior to diagnosis was 12 months (2-96 months). Proximal muscle weakness was seen in all 19 cases, neck muscle weakness in 14, pharyngeal muscle involvement in 5 and respiratory muscle involvement in 3 cases. Heliotrope rash was seen in 9 and Gottrons rash in 8 patients. Myocarditis and GI bleed were seen in 1 each while interstitial lung disease was seen in 2 patients. All except one patient received prednisolone. Methotrexate was used in 13 and azathioprine in 3 patients. Eight patients are in complete remission (CR), 8 partial remission and 2 patients had no response. Complications were calcinosis in 5, contractures in 2, TB in 4 and pyogenic infections in 4 patients. Juvenile dermatomyositis needs to be recognised early and treated aggressively to improve outcome.

Key words: Connective tissue disease, Inflammatory myositis, Calcinosis

Juvenile dermatomyositis (JDM) is a rare multisystem disorder, primarily affecting the striated muscles and the skin. It constitutes about 2% of new diagnoses in a pediatric rheumatology clinic(1). It differs from adult dermatomyositis by the presence of vasculitis and ectopic calcification. In severe cases, death may occur due to respiratory failure, myocarditis or gastrointenstinal hemorrhage. Early diagnosis improves outcome and may prevent complications.

Previous studies from India(1,2) have reported a low prevalence or absence of calcinosis and a favorable outcome. We present a retrospective study of such patients followed up at our center over a period of 12 years.

Subjects and Methods

All patients of JDM (Bohan and Peter criteria)(3) seen in our clinic between 1989 and June 2001 were included. Data on the age of onset, duration of symptoms, clinical features, treatment and outcome were retrieved from the case records. All patients received prednisolone (1-2 mg/kg), with gradual tapering over the next year depending on the clinical response. Additionally, methotrexate (10 mg/m2/week) or azathioprine (2-4 mg/kg/day) was given to patients with partial response at 6-8 weeks treatment with steroids, those with steroid side effects, or severe disease. Cyclosporine and intravenous immunoglobulin were used in refractory cases. The response to therapy was graded as complete remission (normal muscle power, normal enzymes, no systemic features), partial remission (at least 1 grade improvement in muscle power), or no response.

Results

Of 19 patients 12 were boys. The median age at diagnosis was 12 years (range 2.5-16 years) and duration of disease prior to diagnosis was 12 months (range 2-96 months).

Proximal muscle weakness was seen in all cases. Neck muscle weakness, predominantly of flexor muscles was seen in 14, pharyngeal muscle involvement in 5 and respiratory muscle involvement in 3 patients. The classical heliotrope rash was present in 9 patients, Gottron’s rash in 8, palpable purpura in 2 and diffuse erythema in one. Myocarditis with dilated cardiomyopathy and gastrointestinal bleeding were seen in one patient each and interstitial lung disease in 2 patients (Table I).

Elevated serum creatine phosphokinase levels (>192 IU) were present in 13 patients whereas electromyography was abnormal in all 19 patients. Anemia and elevated ESR were common. Antinuclear antibody was positive in 2 patients. Muscle biopsy done in 6 patients showed features suggestive of dermatomyositis.

All patients received prednisolone except one who was diagnosed to have JDM 8 years after the onset of symptoms and the muscle biopsy revealed only peri-fascicular atrophy without inflammation. Methotrexate was used in 13 and azathioprine in 3 patients. One patient received intravenous immunoglobulin since she had no response to treatment with corticosteroids and methotrexate.

Median follow-up period was 12 months (range 2-96 months). At last follow up, complete remission was seen in 8 patients (42.1%), partial remission in 8 (42.1%) and no response in 2 patients. One patient died of respiratory paralysis. Patient number 4 was diagnosed elsewhere at the age of 13 years and was in complete remission when first seen at our center. In the last 8 years, this patient had two relapses, the first responding to treatment with methotrexate and cortiocosteroids. The second relapse was treated with azathioprine and corticosteroids. One patient showed complete remission but her rash persists.


Fig. 1. Ectopic calcification in a child with juvenile dermatomyositis

Complications included calcinosis (Fig.1) in 5 patients, contractures in 2, pulmonary tuberculosis in 4, steroid induced hypertension in 1 and pyogenic infections in 4 patients. The median duration of disease prior to diagnosis in patients with calcinosis was 10 months, which was not different from those without it (median 12 months).

Table I-Clinical Features at Presentation and Outcome
No
Age(yr)
sex
Duration
(months)
Rash
Fever
Arthritis
Others
Follow up
(months)
Outcome
Complications
1
2.5/F
3
+
+
-
Respiratory
involvement
3
Expired
Respiratory failure
2
8/M
5
+
-
+
Calcinosis
43
CR
Hypertension
3
13/M
15
+
+
-
Alopecia,
oral ulcers
29
CR
Tuberculosis
4
13/M
10
+
+
-
Calcinosis
96
CR
Tuberculosis, urinary
 
 
 
 
 
 
 
 
 
infection
5
12/M
4
+
+
+
-
29
CR
Mastoiditis, urinary 
 
 
 
 
 
 
 
 
 
infection
6
13/M
18
+
-
+
DCMP
18
PR
Tuberculosis,
 
 
 
 
 
 
 
 
 
pneumonia
7
13/M
36
+
+
+
-
30
CR
-
8
8/M
4
+
+
+
GI bleed
3
PR
-
9
6/M
6
+
+
+
Calcinosis
2
NR
Pneumonia
10
13/F
2
+
+
-
Respiratory
involvement
16
PR
-
11
12/F
3
+
+
-
-
12
CR
Rash persisting
12
10/M
4
+
-
+
-
2
PR
-
13
10/M
12
+
-
-
-
4
PR
Contractures
14
7/M
30
-
+
+
Tenosynovitis
5
CR
Tuberculosis
15
16/F
96
-
+
+
Calcinosis, ILD
36
NR
Severe muscle disease
16
16/F
12
+
+
-
-
5
PR
Deforming arthritis
17
12/F
36
+
+
+
ILD
24
PR
-
18
15/M
48
-
+
+
Respiratory
involvement
8
CR
-
19
7/F
18
+
-
-
Calcinosis
4
PR
-
ILD - Interstitial lung disease, GI bleed - Gastrointestinal bleeding, DCMP - Dilated cardiomyopathy,
CR, PR and NR - complete, partial and no response

 

Discussion

Our cohort differs from other published from India in the following aspects: longer disease duration prior to diagnosis, more severe disease with involvement of neck and pharyngeal muscles, presence of calcinosis, arthritis, interstitial lung disease and gastrointestinal bleeding and low prevalence of antinuclear antibodies. The longer disease duration and more severe disease are probably related to referral bias to tertiary care centers.

Our patients had a slight male preponderance similar to that reported from Chandigarh(2) and Japan(4) but different from that elsewhere(1,5). The prevalence of antinuclear antibodies was low and similar to that reported by Singh, et al.(2) but different from that reported elsewhere(6). This cannot be explained by a difference in technique as a similar technique i.e., indirect immuno-fluorescence on HEp2 cells was used for the diagnosis.

Eighty percent of our patients showed a satisfactory response to therapy, as reported in other series(1,2). However, almost three-fourths required use of additional immunosuppressives other than corticosteroids. Persistence of rash despite improvement in muscle weakness has been reported in 40% of cases(7), as was seen in one of our patients.

The disease course in JDM may be monocyclic, polycyclic or continuous. Only 2 of our patients (patient number 4,10) have had relapses, most having a monocyclic or chronic continuous course. Relapse in a child with an apparent monocyclic course is uncommon as was observed in one patient after 12 years. No predictors for the course of disease could be identified at the onset of symptoms. Significant morbidity in the form of recurrent pyogenic infections, tuberculosis, calcinosis and contractures were seen in our cases, probably due to use of immunosuppressive agents and late institution of therapy(7).

Calcinosis, the most specific complication of JDM has been reported in 30-70% cases(8,9). Previous studies from India have either not reported or reported a low prevalence of this complication(1,2), probably due to short follow-up. Calcinosis shows a predilection for sites of repeated microtrauma (elbows, knees, flexor surfaces of fingers, buttocks). The reasons implicated for development of calcinosis are a delay in initiation of treatment, polycyclic or unremitting disease course, local trauma and the use of lower doses of corticosteroids(10). Calcinosis is resistant to most therapies including warfarin, ethidronate, probenecid, diltiazem, aluminum hydroxide and lithotripsy(10,11).

Contributors: VC and AW collected the data and wrote the manuscript. AA and RNM planned the study and provided critical inputs to the manuscript. RNM will act as a guarantor for the manuscript.

Funding: None.

Competing interests: None stated.

Key Messages

• Patients with juvenile dermatomyositis seen at tertiary care hospital had longer disease duration and more severe disease.

• Anti-nuclear antibodies are seen in only 10% of patients.

• Majority of patients had good response to treatment.

• Complications included calcinosis and infections due to immunosuppressive treatment.

 

 

 References


1. Seth V, Kabra SK, Semwal OP, Jain Y. Juvenile dermatomyositis. Indian J Pediatr 1996; 63: 375-379.

2. Singh S, Kumar L, Ravi Shankar K. Juvenile dermatomyositis in north India. Indian Pediatr 1997; 34: 193-198.

3. Bohan A, Peter JB. Polymyositis and dermatomyositis. N Engl J Med 1975; 292: 344-347.

4. Hiketa T, Matsumoto Y, Ohushi M, Sasaki R. Juvenile dermatomyositis: a statistical study of 114 patients with dermatomyositis. J Dermatol 1992; 19: 470-476.

5. Rider LG, Okada S, Sherry DD, Wallace CA, Zemel LS, Jacobs JC. Epidemiologic features and environmental exposures associated with illness onset in juvenile idiopathic inflammatory myopathy. Arthritis Rheum 1995; 38(suppl): 362.

6. Pachman LM. An update on juvenile dermatomyositis. Curr Opin Rheumatol 1995; 7: 437-441.

7. Huber AM, Lang B, LeBlanc CMA, Birdi N, Bolaria RK, Malleson P, et al. Medium and long-term functional outcomes in a multicenter cohort of children with juvenile dermatomyositis. Arthritis Rheum 2000; 43: 541-549.

8. Pachman LM, Friedman JM, Maryjowski-Sweeney ML, Johnason O, Radvany RM Sharp GC et al. Immunogenetic studies of juvenile dermatomyositis III. Study of antibody to organ-specific and nuclear antigens. Arthritis Rheum 1985; 28: 151-157.

9. Bowyer SL, Clark RAF, Ragsdale CG. Juvenile dermatomyositis: Histological findings and pathogenetic hypothesis for the associated skin changes. J Rheumatol 1986; 13: 753-758.

10. Bowyer SL, Blane CE, Sullivan DB, Cassidy JT. Childhood dermatomyositis: Factors predicting functional outcome and development of dystrophic calcification. J Pediatr 1983; 103: 882-888.

11. Rider LG, Miller FW. Classification and treatment of the juvenile idiopathic inflammatory myopathies. Rheum Dis Clin Am 1997; 23: 619-655.

Home

Past Issue

About IP

About IAP

Feedback

Links

 Author Info.

  Subscription