The below mentioned article provides a short note on Paragonimus Westermani.
Morpholgy of Paragonimus Westermani:
(Oriental lung fluke) is a reddish brown, plump, ovoidal fluke with rounded anterior end (Fig. 108.16). The eggs are ovoidal and have a flattened operculum (Fig. 108.17).
Life Cycle of Paragonimus Westermani:
Eggs escaping through the bronchioles are coughed up, are swallowed and passed out of faeces. They hatch out miracidia in the water which swim in the water and attack the snails in which redia (Fig. 108.18), cercariae (108.19) produced liberated swim in the water and invade the viscera of Cray fish or crab where the metacercariae encyst
Man becomes infected by ingestion of infected crabs. The metacercariae excyst in the duodenum and migrate through the intestinal wall, reach the abdominal cavity and travel through the diaphragm to the pleural cavity and settle in the lungs.
Clinical Features of Paragonimus Westermani:
Chest pain, night sweats are common symptoms. Paroxysmal coughing is followed by haemoptysis after physical exertion. The manifestations are severe. Bronchopneumonia, or bronchiectasis with pleural effusion are the physical signs. Diagnosis by the finding of the characteristic egg in the sputum or faeces. The complement fixation test may be positive.
Treatment of Paragonimus Westermani:
Emetine hydrochloride, bithional and hexachloroparaxylol are found effective.
Prophylaxis:
(1) Avoid eating raw crabs;
(2) Destroy the snails;