Author: Lauren Thomas, 3rd Year Postgraduate Medical Student, Flinders University, Northern Territory, Australia; Chief Editor: A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand, April 2016.
Sparganosis is a zoonosis, ie an infection passed on from animals such as snakes and frogs, and occasionally from eating pig or dog meat. It is caused by infection with the larval form of various species of Spirometra. These include:
The spargana tapeworm normally lives in the intestines of animals such as cats and dogs, and has two intermediate hosts.
Sparganosis can occur in people who have:
It occurs in residents of the following countries:
Sparganosis is occasionally diagnosed in other countries among travellers. Reported cases describe a higher incidence in females compared to males.
Sparganosis may arise when individuals drink water contaminated with copepods infected with spargana larvae, or when they consume improperly cooked meat. It can also be caused by topical application of tissue derived from infected animals.
Spargana larvae penetrate the intestinal wall and migrate to other tissues.
Adult spirometra tapeworms are rarely seen in human beings.
The clinical features of sparganosis are non-specific and it can be easily missed. Symptoms depend on which tissues the larvae have migrated to.
Cutaneous sparganosis occurs when sparganum larvae invade subcutaneous connective tissue and superficial muscles.
Ocular sparganosis depends on the exact location of spargana within the eye. It may present as:
Larvae in the cerebral hemisphere can cause:
If spinal canal is involved, sparganosis may cause:
Visceral spargana can invade breast, intestine, lung, heart or abdominal cavity.
Proliferative sparganosis can invade and spread from any organ.
Definitive diagnosis of sparganosis is based on the larvae being found in tissue samples.
Spargana are removed surgically.
If the worm is in lung or pericardium, surgery is not practical.
Other treatment options include:
If not killed by treatment, spargana can live for 20 years in a human host.
Repeated serological tests are needed to prove clearance.
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