Purpose or Case Report: Sparganosis is a rare parasitic infection caused by the plerocercoid larvae of Spirometra spp. That is seldom encountered in humans. Clinical presentations are often nonspecific, and imaging findings can mimic other soft tissue lesions and lead to misdiagnosis. We present a case of a 14-year-old female with an abdominal wall lesion initially suspected to be cutaneous endometriosis, which was later diagnosed as sparganosis.

Case Presentation:
A 14-year-old female presented with a progressively enlarging, tender subcutaneous mass located superior and left of the umbilicus. The lesion was associated with intermittent pain, particularly exacerbated during menstruation, which raised clinical suspicion for cutaneous endometriosis. Abdominal MRI revealed a 2.5 cm subcutaneous mass with heterogeneous signal intensity on both T1- and T2-weighted images. Areas of hyperintensity suggested hemorrhagic components, which can be seen with endometriotic implants.

The patient underwent surgical excision of the mass. Intraoperatively, a well-defined subcutaneous lesion was removed without complications. Histopathological examination unexpectedly revealed a cestode consistent with Spirometra spp. (sparganosis), along with mixed inflammation, granulation tissue formation, and focal necrosis. The cystic structure corresponded to the parasite's infection site. Postoperative management included prescribing albendazole therapy following stool sample collection to rule out residual parasitic infection.

Discussion:

Sparganosis is an uncommon parasitic infection in humans that is typically acquired through ingestion of contaminated water or undercooked meat from intermediate hosts. It often presents as a slowly growing subcutaneous mass, which can be mistaken for other soft tissue lesions such as lipomas, cysts, or, as in this case, endometriosis. Imaging findings are nonspecific; MRI may show cystic or solid masses with variable enhancement patterns. In this patient, MRI findings closely resembled cutaneous endometriosis due to the presence of hemorrhagic components within the lesion.

Definitive diagnosis of sparganosis is usually established postoperatively via histopathological identification of the parasite. This case demonstrates the importance of considering parasitic infections in the differential diagnosis of subcutaneous masses.
Methods & Materials:
Results:
Conclusions: