Clinical Features:
The acute phase (invasion and migration) may be marked by diarrhea, abdominal pain, fever, cough, urticaria, hepatosplenomegaly, pulmonary abnormalities, and eosinophilia.  During the chronic phase, pulmonary manifestations include cough, expectoration of discolored sputum, hemoptysis, and chest radiographic abnormalities.  Extrapulmonary locations of the adult worms result in more severe manifestations, especially when the brain is involved.

Laboratory Diagnosis:
Diagnosis is based on microscopic demonstration of eggs in stool or sputum, but these are not present until 2 to 3 months after infection.  (Eggs are also occasionally encountered in effusion fluid or biopsy material.)  Concentration techniques may be necessary in patients with light infections.  Biopsy may allow diagnostic confirmation and species identification when an adult or developing fluke is recovered.

Diagnostic findings

• Microscopy
• Antibody detection is useful in light infections and in the diagnosis of extrapulmonary paragonimiasis.
• Morphologic comparison with other intestinal parasites

Treatment:
Praziquantel* is the drug of choice to treat paragonimiasis.  Bithionol is an alternative drug for treatment of this disease.  See recommendations in The Medical Letter for complete information.

* This drug is approved by the FDA, but considered investigational for this purpose.