spinigerum
is a parasite found in dogs and cats. Human infections of the disease have been reported from Japan China, Thailand, Far East and Philippines.Life cycle
The life cycle of
this parasite involves 2 intermediate hosts, cyclops and birds, snakes, fish and frogs where they mature. The eggs are passed in the faeces and then into water where they are ingested by cyclops. They, in
turn, are ingested by a number of fresh water fish, frogs, snakes and birds where they encyst in the muscle. Cats and dogs ingest the raw flesh of these animals and the larvae excyst and mature into adults in the
stomach of cats and dogs.
Morphology
The adult female worms measure 25 - 54 mm whereas the male measures 11 - 25 mm The anterior
half of the worm is covered with leaf like spines. The larval worms are 4mm.
Clinical Disease
Humans are accidental hosts and after ingestion, the larvae do not mature but migrate
throughout the body via the intestinal wall. Symptoms include epigastric pain, vomiting and anorexia. These symptoms subside as the larvae continue their migratory path through the cutaineous tissue.
Evidence of migration appears as either lesions similar to cutaineous larvae migrans or migratory swellings accompanied by inflammation, redness or pain. The swelling is hard and non-pitted and lasts for several
days. These migratory lesions may be accompanied by pruritis and pain There is marked eosinophilia in patients with cutaineous involvement. Ocular involvement resulting in blindness may occur in serious
disease. Eosinophillic myeloencephalitis may result from migration of the worms along the nerve tracks. Symptoms may include pain, paralyses, seizures, coma and death. The CSF may be xanthochromic or bloody.
Diagnosis
Presumptive diagnosis may be made on the basis of clinical symptoms. Definitive diagnosis is the
recovery and identification of the worm since the symptoms may be suggestive of sparganosis,
paragonimiasis and cutaineous larvae migrans and myasis. A bloody spinal fluid or xanthochromia may
resemble infection with Angiostrongylius contonensis.
