Journal of The Association of Physicians of India ■ Vol. 64 ■ March 201694

Isolated MyocysticercosisS Vignesh1, Chetan Bhole1, Chander Bafna2, Neeraj Nirala2, Mehul Prajapati3, Neera Samar4, RL Meena5

Abstract Cysticercosis, a parasitic disease caused by larval form of Taenia solium, is a major health concern in the developing world. The encysted larval stage can affect any part of the body, but are most frequently detected in brain, eye, skeletal muscle and subcutaneous tissue. Most muscular cysticercosis are almost always associated with central nervous system involvement or with multiple intramuscular cysts or both. Here we report an unusual case of cysticercosis in right rectus muscle which was an isolated muscle involvement without any other systemic manifestation.

1Junior Resident 3, 2Junior Resident 2, 3Junior Resident 1, 4Associate Professor, 5Professor and Unit Head, Department of Medicine, RNT Medical College, Udaipur, RajasthanReceived: 14.01.2015; Accepted: 28.01.2015

Introduction

Cysticercosis is the tissue infection caused by the larval form of the

pork tapeworm, Taenia solium.1 The occurrence of cysts in humans in order of f requency is the central nervous system, vitreous humor of eye, striated muscle, subcutaneous tissue and rarely other tissues. Most muscular disease is associated with central nervous system involvement or presence of multiple intramuscular cys ts or both . I so la ted muscular involvement is a rare finding and because of the non-specific symptoms, isolated soft tissue cysticercosis is very difficult to diagnose. Till date there are only a handful of cases of isolated muscular cyst icercosis reported. 2 D iagnos i s i s made by computed tomography, magnet ic resonance imaging, serological investigations and histopathology.4 In Indian scenario, this case needs documentation in the medical literature so that clinicians can have a differential diagnosis of an asymptomatic lump under the skin.

Case History

A 18 yrs old female presented with asymptomatic abdominal swelling for pas t one month in her r ight hypochodrium. Examination revealed a 1*2 cm non-tender, mobile, globular swell ing, not f ixed to the skin or underlying structures, and it was prominent with head rising. Rest of the examination was normal. USG abdomen showed a hypoechoic lesion measuring of approximate ly 8*5 mm with a central anechoic area and calcification noted inside the right rectus muscle suggestive of granulomatous lesion (Figure 1). Her dietary history also revealed occasional pork consumption. Her Absolute eosinophil count was only 100 (Ref range: 40-440). ELISA for anti-cysticercal antibody was also negative. MRI abdomen was done which revealed

a sub-centimeter sized well defined rounded lesion in the right rectus muscle likely to represent inflammatory granuloma – cysticercosis (Figure 2). Fundus examination and MRI brain was normal. Surgical excision was done (Figure 3) and on HPE cysticercosis was confirmed as the parasite was identified (Figures 4 and 5).

Discussion

Human cysticercosis is caused by infestation of Cysticercus cellulosae , the larval form of Taenia solium which results from eating food (undercooked pork or beef and raw vegetables) and water contaminated with viable eggs of Taenia solium.2,3 Infestation of the human intestine with an adult tapeworm is known as Taeniasis, whereas tissue infestation is called Cysticercosis.1 Involvement of the central nervous system is called neurocysticercosis. Human are the only definite host while human and pigs can act as an intermediate host.

Cysticercosis can affect various organs including the brain, spinal cord, orbit, muscle, subcutaneous tissue and even heart. Clinical manifestations depend upon anatomic site of larval encystment , number of cysts and associated inflammatory response or scarring.3 Soft tissue cysticercosis

Fig. 1: USG abdomen - hypoechoic lesion with a central anechoic area and calcification in right rectus muscle

Fig. 2: MRI Abdomen - sub-centimeter sized well defined rounded lesion in the right rectus muscle likely to represent inflammatory granuloma – cysticercosis

Fig. 3: Macroscopic appearance of the biopsied pearly white cyst

Journal of The Association of Physicians of India ■ Vol. 64 ■ March 2016 95

frequently presents with multiple intramuscular lesions and central nervous involvement usually. Isolated soft tissue involvement is rare and clinically confused with other soft tissue lesions like neoplasm and other infective or inflammatory pathologies.3 The most common presentation and site of soft tissue cysticercosis is a lump in upper extremities. Abdominal and chest wall lesions are seen less often.1

Isolated soft tissue cysticercosis is often used as a marker of neurocysticercosis and an evaluat ion for coexis t ing

central nervous system, and ocular involvement is recommended.5

S e r o l o g i c a l t e s t f o r s p e c i f i c anti-cysticercal antibodies has low sensitivity when the parasite burden is

Fig. 4: Microscopy showing the cysticercus

Fig 5: Microscopy showing multiple scolices with refractile hooklets

low as in solitary lesions. Radiological modalities like CT, MRI play a crucial role in establishing the diagnosis.3 High-resolution sonography can clench the diagnosis by demonstrating the presence of a scolex within the cyst.1 FNAC or excision biopsy provides most definitive diagnosis. The cyst is usually filled with clear fluid or sometimes it is pearly white and may show presence of scolex or parasite fragments.

Treatment of cysticercosis depends upon the site of involvement, number of cysts and symptoms of the patient. Isolated soft tissue cysticercosis can be treated with surgical excision along and/or with antihelminthic medications like albendazole or praziquantel.3

In conclusion, isolated soft tissue cysticercosis is a rare entity and in a developing country like India it

should be always kept as a differential for solitary abdominal lump and HPE studies (FNAC or biopsy) should always be carr ied out to conf irm even in the absence of eosinophilia or serological evidence, like in our case and when Myocysticercosis is confirmed Neurocysticercosis should be ruled out by brain imaging always. Measures for prevention of the disease by proper cooking of meat, proper sani ta t ion and hygiene prac t i ces and boiled and clean drinking water habits should be emphasized. Prompt recognition and early treatment of cysticercosis is always beneficial.

References1. Singh AP,Maurya DP,Gupta P,Tanger R,Goyal RB,Sharma M.A

Rare Case of Cystiercosis of the Abdominal Wall. Int J Sci Stud 2014; 2:149-150.

2. Rangdal SS, Prabhakar S, Dhat SS, Prakash M, Dhillon MS. Isolated Muscle Cysticercosis: A rare Pseudotumur and diagnostic chalengel,can it be treated Nonoperatively? A report of two cases and review of literature. J Postgrad Med Edu Res 2012; 46:43-48.

3. Gupta MK, Ahmad K, Ansari S, Rauniar RK, Chaudary S. Isolated Cysticercosis of Anterior Abdominal wall mimicking clinically as acute appendicitis: An unusual presentation. Journal of Universal College of Medical Sciences 2013; 1:45-47.

4. Naik D, Srinath M, Kumar A. Soft tissue cysticercosis Ultrasonographicspectrum of the disease. Indian J Radiol Imaging 2011; 21:60-2.

5. Khan RA, Wahab S, Chana RS. A rare cause of solitary abdominal wall lesion. Iran J Pediatr 2008; 18:291-2.

6. Evans CAW, Garcia HH, Gilman RH. Cysticercosis. In:Strickland GT(Ed). Hunter`s tropical medicine (8th ed). Philadelphia, PA:WB Saunders CO 2000; 862.