The below mentioned article provides a short note on Gastrodiscoides Hominis.
Morphology of Gastrodiscoides Hominis:
The living worm (Fig. 108.9) is bright pink in colour and pyriform in outline. Its eggs are ovoidal operculate. Its life cycle is unknown. In man, it produces clinically mucous diarrhoea. In the laboratory it can be diagnosed by the demonstration of the typical eggs in the faeces.
Other Trematodes:
Clonorchis sinensis (Chinese liver fluke) is flat, transparent, fleshy and spatulate (Fig. 108.10). Its eggs are ovoidal, light yellowish and operculated (Fig. 108.11).
Life cycle:
When fully embryonated eggs containing miracidium are ingested by snails, the miracidium hatches out from the egg and transforms ultimately into cercariae (Fig. 108.12) which escape from the snails and swim in the water.
On contact with fresh water fish, these cerceriae attach to the fishes and encyst in the skin or in the flesh. Man gets infected by ingestion of infected fish, the metacercariae excyst in the duodenum and enter the common bile duct where they mature and discharge eggs.
Clinical features:
There are three stages in the manifestation of symptoms:
(1) The mild, symptomless;
(2) The progressive stage with irregular appetite, fullness in the abdomen, diarrhoea and hepatomegaly, and
(3) The severe stage with portal cirrhosis syndrome.
Catarrhal cholangitis occurs due to occlusion of the bile passages of sticky masses of eggs and by tissue proliferation. Symptoms of systemic toxaemia are palpitation of the heart, tachycardia, vertigo, tremor, cramps and mental depression.
Diagnosis can be done by Indirect ELISA; Double sandwich ELISA for mass survey. Opisthorchis felineus : (Cat liver fluke) is morphologically similar to C. sinensis (Fig. 108.13) and also its eggs (Fig. 108.14). Its life cycle is too similar, but the cercariae (Fig. 108.15) attack fish. Clinical features, diagnosis, prophylaxis are similar to those of C. sinensis, but there is no specific treatment.