A Case Report of Sparganosis Mansoni Parasitic Infection of Tennon's Capsule

Sparganosis mansoni is a parasitic infection caused by the plerocercoid larva of Spirometra mansoni, a tapeworm commonly found in amphibians and reptiles. Humans become accidental hosts through ingestion of contaminated water or undercooked intermediate hosts, with larvae capable of migrating to subcutaneous tissues, the eyes, or the central nervous system.

This case describes a rare presentation of ocular sparganosis in a middle-aged man with no known exposure to traditional risk factors. The live S. mansoni larva, discovered within the Tenon's capsule and measuring 22 cm, underscores the diagnostic challenge and the importance of considering parasitic infections in atypical orbital masses.

This case highlights the diagnostic challenges of ocular sparganosis, particularly when clinical signs are subtle and conventional tests are inconclusive. To our knowledge, based on a structured review of the available literature, this appears to be the first reported case of sparganosis localized exclusively to Tenon's capsule. Clinicians should consider parasitic infections in the differential diagnosis of atypical subconjunctival or orbital masses, especially in endemic regions. Public health education regarding the risks of exposure to untreated water sources remains critical in preventing such infections.