Sparganosis is infection with larvae of the tapeworm Spirometra mansoni and related species.

Spirometra mansoni affects dogs, cats, and other carnivores. Eggs are passed into freshwater where they are ingested by copepods (eg, Cyclops). Frogs, reptiles, and various small mammals ingest them and serve as intermediate hosts. Humans can become infected by accidental ingestion of copepods from water contaminated by cat or dog feces, ingestion of inadequately cooked flesh from another intermediate host, or contact with poultices containing flesh from these sources. In humans, larvae typically migrate to subcutaneous tissue or muscle and form slowly growing masses. Other sites, including the CNS, may be involved but are much less common. Symptoms are caused by mass effect.

Diagnosis is typically made after surgical removal, although it may be suggested when imaging detects a mass. Surgery is also the primary treatment and is typically done for symptomatic, space-occupying lesions.

Last full review/revision December 2009 by Richard D. Pearson, MD

Content last modified February 2012