Hydatid cyst in the teres major muscle and brain

A 46-year-old male patient presented with a headache that persisted for 1 year. Physical examination revealed no abnormalities. Contrast-enhanced cranial computed tomography (CT), requested with a provisional diagnosis of a mass, revealed cystic lesions in both cerebral hemispheres, the largest of which was 2 cm in size, without contrast enhancement (Figure 1). Magnetic resonance imaging of the patient's brain revealed multiple round, multivesicular T1-hypointense and T2-hyperintense lesions in both cerebral hemispheres (Figure 2). These findings were significant with respect to hydatid cysts. Non-contrast thoracic CT was performed during the patient's general physical examination. A 22 × 10 mm hyperdense, septate cystic lesion was noted in the right teres major muscle (Figure 3). Postoperatively, a hydatid cyst was confirmed pathologically.

FIGURE 1:
Presence of cystic lesions in both cerebral hemispheres, the largest of which is 2 cm in size, without multivesicular contrast enhancement.

FIGURE 2:
Magnetic resonance imaging of the patient's brain reveals multiple round, multivesicular T1-hypointense (A) and T2-hyperintense (B) lesions in both cerebral hemispheres.

FIGURE 3:
Radiological examination reveals a hyperdense, septate cystic lesion in the right teres major muscle.

Cystic echinococcosis (hydatid disease) is a zoonotic parasitic disease caused by the ingestion of Echinococcus granulosus eggs that can form cysts anywhere in the body. The prevalence of the disease ranges from 0 to 79 cases/100,000 population¹. Hydatid cysts most commonly affect the liver (55-70%), followed by the lungs (18-35%). The incidence of the cerebral form is 1-2%², and that of the muscular form is approximately 1-5%³. Hydatid cysts should be considered in the differential diagnosis of well-defined cystic masses unresponsive to medical treatment in individuals from endemic regions.

ACKNOWLEDGMENTS

None.

REFERENCES

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• Financial Support: None.

Publication Dates

• Publication in this collection
  24 Oct 2022
• Date of issue
  2022

History

• Received
  13 July 2022
• Accepted
  15 Sept 2022