Benign Acute Childhood Myositis - medIND

Original Article 

Benign Acute Childhood Myositis 

Sarala Rajajee, S. Ezhilarasi and K. Rajarajan 

Kanchi Kamakoti CHILDS Trust Hospital, Chennai, India. 

Abstract. Objective: To describe the clinical and laboratory features of benign acute childhood myositis. Methods : 40 children 

of BACM were seen during October 2001 to February 2002, 22 (52%) were male with mean age of 5.3 years. Duration of illness 

was 3.97 days. Preceding symptoms included fever, leg pain, vomiting and inability to walk. A provisional diagnosis of viral 

myositis was made in 26 (66%). Guillian Barre Syndrome was the most common referral diagnosis. Results: 11 (27.5%) 

children had leucopenia with lymphocytic response and 16 (40%) had thrombocytopenia. CRP was negative in 32 (80%). CPK 

was markedly elevated (more than 1000 IU/l) in 18 (45%) and more than 500IU/l in 11 (27.5%) remaining between 200 to 500IU/ 

l. Associated features were hepatitis (elevated SGOT & SGPT) in 28 (70%) and shock in 5 (12.5%).Serological test were 

indicative of dengue virus (Elisa PAN BIO) in 20 (50%) of which 8 (25%) were primary dengue and 12 (30%) were secondary 

dengue. The outcome of therapy mainly supportive were excellent. Conclusion: Benign acute myositis occurs often in 

association with viral infection. In the present study, Dengue virus was positive in 20 (50%) children. Benign acute myositis can 

be differentiated from more serious causes of walking difficulty by presence of calf and thigh muscle tenderness on stretching, 

normal power and deep tendon reflex and elevated CPK. [Indian J Pediatr 2005; 72 (5) : 399-400] 

E-mail : [email protected] 

Key words : Myositis; Dengue virus; Guillian Barre Syndrome 

Benign acute childhood myositis (BACM) was first 

described in 1957 by Lundberg 1 under the name of 

“Myalgia Cruris Epidemica”. It is characterised by 

sudden onset of calf pain and refusal or difficulty to walk. 

Viral agents have been implicated. 1,2,3,4 It is followed by 

rapid recovery within a week. It is rarely reported in 

adults. We report 40 cases of BACM between October 

2001 to February 2002. 

MATERIAL AND METHODS 

Inclusion criteria: (i) Children presenting with fever / 

myalgia. (ii) Muscle tenderness demonstrated by straight 

leg raising test (iii) Absence of nuchal rigidity. (iv) 

Absence of neurological signs such as altered sensorium 

or local deficit. 

RESULTS 

Forty cases of BACM were seen. 22 (55%) were male with 

mean age of 5.3 years age. All cases were seen between to 

October 2001 – February 2002. Duration of illness was 3.97 

days. Preceding symptoms included fever, leg pain, 

headache. 

A provisional diagnosis of viral myositis was made in 

26 (65%). Guillian Barre syndrome was the most common 

referral diagnosis in 5 (12.5%). 18 (45%) children were 

unable to walk and in those who walked a characteristic 

Correspondence and Reprint requests : Dr. Sarala Rajajee, 19 (New 

No 28) Second Main Road, CIT Colony, Chennai – 600 004. 

pattern were observed, they walked on toes or walked 

with wide based, stiff gait. Muscle tenderness was 

recorded in 34 (85%) cases. This was well illustrated by 

stretching of the muscle by raising the leg. Similar 

observations were made by Mackary et al. 5 

Eleven children (27.5%) had leucopenia, with 

lymphocyte response 16 (40%) had thrombocytopenia. 

CRP was negative in 32 (80%). CPK was markedly 

elevated (more than 1000 IU/litre) in 18 (45%), and more 

than 500 IU/litre in 11 (27.5%) (Fig 1). Serological tests 

were indicative of dengue virus (Elisa PAN BIO) primary 

Dengue in 8 (25%), secondary Dengue in 12 (30%). 

Associated features were hepatitis in 28 (70%) 

(elevated SGOT and SGPT) shock in 5 (25.5%). 

The outcome of the therapy was excellent, everybody 

recovered. Repeat CPK was normal in 10 (25%). Rest of 

the children were asymptomatic at review after two 

weeks. Therapy was mainly supportive with intravenous 

fluids as indicated and paracetamol. 

DISCUSSION 

After the first reports of BACM in 1957 1 , Middleton et al 2 

described cases in 1970 and showed elevated CPK in 

association with influenza B. Since then there have been 

253 cases reported associated with various virus 

infections. 

In the present series 55% of patients were boys. In the 

report by Mackary et al 84% of patients were boys. This 

may be either due to greater levels of activity in boys or a 

genetic predisposition. 

Indian Journal of Pediatrics, Volume 72—May, 2005 399

No. of cases 

20 – 

16 – 

12 – 

8 – 

4 – 

0 – 

12 

135-500 500-999 >1000 

CPK levels (IU/litre) 

Fig 1. Creatine Phosphokinase (CPK) 

The mean age of onset of symptoms in our study was 

5.3 days. The mean duration of prodromal symptoms in 

the present study was 3.97 days. There was associated 

clinical features of hepatomegaly in 33 (82.5%) cases. 

Shock in 5 (12.5%). Resolution was rapid within as week. 

This was similar to the observation of Mackary et al and 

Mckinlay et al. Myalgia primarily affected the 

gastroneomius and hamstring muscles. 

Viruses associated with myositis according to several 

authors include Influenza A, adenovirus , Coxsackie and 

para influenza. In the present series the Dengue virus was 

11 

Sarala Rajajee et al 

18 

MOTHER & CHILD CARE 

(Hindi & English) 

associated with 20 (50%) cases of myositis. 

Muscle biopsies performed in myositis showed non 

specific degenerative changes, focal muscle fibre 

vacuolation and muscle necrosis. The elevation of CPK 

suggests muscle fibre destruction in keeping with a 

myositic component. 

Awareness of the possibility of myositis in children 

presenting with acute myalgia, difficulty in walking in 

association with elevated CPK may lead to streamlining 

further tests and unnecessary therapy may be avoided. 

Contributions 

SR drafted the manuscript. KR collected the data. SE analysed the 

data. SR will act as the guarantor of the paper. 

REFERENCES 

1. Lundberg A Myalgia cruris epidermica. Acta Paediatr 1957; 

46 : 18-31. 

2. Middleton PJ, Alexander RM. Severe myositis during 

recovering from influenza. Lancet 1970; 2 : 533-535. 

3. Anthony J H, Procopis PG, Ouvier RA. Benign acute 

childhood myositis. Neurology 1979; 29 : 1068–1071. 

4. Mckinlay IA, Mitchell I. Transient acute myositis in childhood. 

Arch Dis Child 1976, 51; 135-137. 

5. Mackay MT, Kornverg AJ, Shield LK, Dennett X. Benign acute 

childhood myositis. Neurology 1999; 53 : 70. 

6. Mark Barasz. Benign acute myositis. Am J Emerg Med 2000; 

18 : 35-37. 

By Utpal Kant Singh, Rajiniti Prasad, Ranjeet Kumar and Shivani Suman 

Published by Jaypee Brothers, Medical Publishers (P) Ltd 

EMCA House, 23/23B, Ansari Road, Daryaganj, New Delhi-110002, India. 

First Edition : 2003 (English), First Edition : 2005 (Hindi) 

Price : Rs 125/- (Each) 

Order from : The Indian Journal of Pediatrics 

125, IInd Floor, Gautam Nagar, New Delhi-110049. 

Mother & Child Care is a practical handbook on scientific dealing with mother and child without 

neglecting beneficial traditional beliefs. It covers practically useful chapters on common childhood 

illness, emergencies and first aid. 

400 Indian Journal of Pediatrics, Volume 72—May, 2005

Benign Acute Childhood Myositis - medIND

Create successful ePaper yourself

Delete template?

Save as template ?