Intramuscular cysticercosis diagnosed on ultrasonography in thigh: A rare case report

www.najms.org North American Journal of Medical Sciences 2010 March, Volume 2. No. 3.

Case Report OPEN ACCESS


Intramuscular cysticercosis diagnosed on
ultrasonography in thigh: A rare case report

Rikki Singal, MS, FICS1, Amit Mittal MD2, Sanjeev Gupta MD3, Raman Gupta, MS4,
Pradep Sahu, MS,Mch1, Anupama Gupta, MS5
1Department of Surgery, 2Radiodiagnosis, 3Dermatology and Venerology, M.M. Institute of Medical Sciences & Research,
Mullana, (Distt-Ambala), Haryana, India. 4Departments of Surgery, and 5Anatomy,
Adesh Institute of Medical Science & Research, Bathinda, Punjab, India.

Citation: Singal R, Mittal A, Gupta S, Gupta R, Sahu P. Gupta A. Intramuscular cysticercosis diagnosed on
ultrasonography in thigh: A rare case report. North Am J Med Sci 2010; 2: 162-164.
Availability: www.najms.org
ISSN: 1947 – 2714


Abstract
Context: Cysticercosis is an infection with the larval (cysticercus) stage of Taenia solium. It is difficult to diagnose
cysticercosis on ultrasonography. Ultrasonography was done on Logiq 500 Pro machine with convex probe at 3.5 MHz
frequency and diagnosed as cysticercosis with surrounding inflammation in the right vastus medialis muscle of thigh with a
linear probe at 9.6 MHz frequency. In this case, we are discussing the role of high resolution sonography which helped in
non-invasive diagnosis and treatment. Case Report: A 12 years old male patient presented with a swelling on the medial
aspect of the right thigh. There was complaint of pain in the right thigh for the last one week with history of fever since
three days. On local examination, a single swelling of size approximately 4x5 cm in the right medial aspect of thigh was
present. On ultrasonography there was a well defined isolated cystic lesion of size 3.3 x 2.5 cm intermuscular area. We
have successfully managed the patient conservatively with albendazole and steroids only. Conclusion: We conclude that
intermuscular cystic swelling in thigh can be diagnosed on high resolution sonography with a great confidence to manage it
conservatively. Cost of investigations also reduced. Ultrasonography plays an important role. Child is doing well in
follow-up.

Keywords: Cysticercosis; intramuscular; high resolution sonography; noninvasive; diagnosis; medical management

Correspondence to: Rikki Singal, Assist Prof, MS, FICS. Department of Surgery, M.M. Institute of Medical Sciences and
Research, Mullana (Distt –Ambala), Pin Code - 133203, Haryana, India. Tel.: 09996184795, Fax: 01731304550. Email
singalrikki@yahoo.com, or singalrikki@live.com


Introduction
the right thigh. There was a single swelling of size
approximately 4x5 cm in the right medial aspect of thigh
Cysticercosis is an infection with the larval (cysticercus)
(Fig. 1). Multiple small tiny spots were present over the
stage of Taenia solium [1]. It is seen as cysts in various
thigh. There was difficulty in extension of thigh of about
human tissues, more commonly in the brain and the orbit.
20 degree. Rest of the clinical examination was normal.
The muscular form of cysticercosis is generally
Routine investigations were within normal limits. Patient
asymptomatic and 3 different clinical manifestations are;
was sent for the ultrasonography of the whole abdomen
the myalgic, myopathic type; the nodular or mass like type;
and thigh.
and the rare pseudohypertrophy type [2, 3].


Ultrasonography (USG) was done on Logiq 500 Pro
Case Report
machine (GE Medical Systems, USA) with convex probe
A 12 years old male patient presented with a swelling on
at 3.5 MHz frequency and with a linear probe at 9.6 MHz
the medial aspect of the right thigh. There was complaint
frequency. On ultrasonography there was a well defined
of pain in the right thigh for the last one week with history
isolated cystic lesion of size 3.3 x 2.5 cm intermuscular
of fever since three days. There was also complaint of
area (Fig. 2). There was small cystic lesion in the right
difficulty in walking. No other relevant history was
vastus medialis muscle with surrounding inflammatory
present. Patient was totally vegetarian. On local
phlegmon of 4 x 3 cm. and leaked echogenic scolex was
examination, temperature was raised with tenderness on
also seen with linear probe. Therefore, on sonography, the

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diagnosis of cysticercosis in the right vastus medialis
muscle of size 3.3 x 2.5 cm with surrounding inflammatory
muscle was made with surrounding inflammatory
phlegmon.
phlegmon (Fig. 3). Rest of the abdomen was normal. The

patient was managed conservatively with short course of
Discussion
tapering steroid, prednisolone 2mg/kg/day and on tablet
Soft tissue cysticercosis in humans is caused by encysted
albendazole 15mg/kg body weight/day for 21 days. After
larvae of Tapeworm Taenia solium. Cysticercosis is rare in
three weeks of conservative treatment, on follow up, pain
Europe and North America but not in Central and South
and tenderness completely disappeared and patient was
America, Africa, India, and China [3]. The cases of this
well. On follow up sonography, there was no evidence of
potentially fatal infection in the West may be related to
phlegmon or cysticercosis in thigh. Patient was followed
immigration and the increase in travel to tropical countries
again after three months and there were no complaints.
[4]. Tapeworm infection is common in developing

countries where the combination of rural society, crowding,
and poor sanitation allows greater contact between humans
and pigs and thus more opportunities for fecal
contamination of food and water [5, 6]. Normally, humans
are the definitive hosts for T solium, the life cycle of
which begins with ingestion of viable larvae
in inadequately cooked pork.

The organism is transmitted to humans by ingestion of
eggs from contaminated water or food, such as vegetables,
or by internal regurgitation of eggs into the stomach due to
reverse peristalsis, when the intestine harbours a gravid
worm. The eggs hatch in the small intestine, releasing
oncospheres that penetrate the bowel mucosa and enter the

bloodstream to reach various tissues, where they develop
Fig. 1 Swelling seen anterio medially in the right thigh
to form cysticercus cellulosae, which is the encysted larval

form of T. solium. When the larva dies, it induces a
vigorous granulomatous inflammatory response that
produces symptoms, depending on the anatomic location
[1]. In cysticercosis, the patient usually presents as in
asymptomatic way. In our case, patient reported to us with
a swelling in middle and medial aspect of right thigh with
difficulty in walking and pain.

The clinical symptoms of cysticercosis depend on the
number and location of cysticerci, as well as the extent of
associated inflammation. The organism most often invades
the central nervous system, eye, subcutaneous tissue,
skeletal muscle and heart, but occasionally the lungs, liver

and kidney may be affected. In the muscular form, three
Fig. 2 High resolution sonography showing irregular cyst (solid
distinct types of clinical manifestations have been
arrow) with leaked echogenic scolex (dotted arrow) with
described: the myalgic type; the mass-like, pseudotumour
surrounding inflammation in intermuscular area

or abscess-like type; and the rare pseudohypertrophic type
[1, 6]. There are only few reported cases of the muscular
cysticercosis diagnosed on ultrasound [5, 7-9].

With the help of high resolution sonography, we have
made the diagnosis of the intermuscular cysticercosis
which presented clinically as swelling in thigh. The
hyperechoic structure within the cystic lesion corresponds
to the scolex of the cysticercus. Living cysticerci actively
evade immune recognition and do not cause inflammation;
however, during the death of larvae, leakage of fluid from
the cysts may trigger an acute inflammatory response. This
inflammatory response may appear as a surrounding
hypoechoic lesion in the muscle which causes local pain

and myalgia. One of the sonographic appearances of
Fig. 3 On linear probe ultrasonography
cysticercosis is the cysticercus cyst with an inflammatory

mass around it, as a result of the death of the larva. The
Diagnosis made as cysticercosis in the right vastus medialis
second type is an irregular cyst with very minimal fluid on

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one side, indicating the leakage of fluid. The eccentric
parasite. Steroids are used as anti-inflammatory as most of
echogenic protrusion from the wall due to the scolex is not
the surrounding phlegmon is inflammatory reaction to the
seen within the cyst. It may be due to escape of the scolex
cyst.
outside the cyst or partial collapse of the cyst as was seen

in our case. The third appearance is a large irregular
Conclusion
collection of exudative fluid within the muscle with the
Cysticercosis should always be kept as a differential
typical cysticercus cyst containing the scolex, situated
diagnosis in all kinds of subcutaneous swellings in
eccentrically within the collection.
endemic regions. High-resolution sonography, being

noninvasive and nonionizing, plays an important role in
This may be due to chronic intermittent leakage of fluid
establishing the diagnosis in patients with muscular
from the cyst, leading to florid inflammatory exudates.
cysticercosis. Therefore, we conclude that intermuscular
This appearance is similar to an intramuscular abscess, but
cystic swelling in thigh can be diagnosed on high
the visualization of the cysticercus cyst within it clinches
resolution sonography with a great confidence without any
the diagnosis. In, all three of these types of appearances,
need of FNAC/biopsy and easy to manage conservatively.
the salient diagnostic feature is that of the cysticercus itself,

which appears as an oval or round well-defined cystic
lesion with an eccentric echogenic scolex in it, as was seen
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