Objective: To study the clinical manifestations and pathologic findings of paragonimiasis.
Methods: Nine cases of paragonimiasis diagnosed in the Peking Union Medical College Hospital during the past 20 years were studied, with literature review and analysis of the epidemiological, clinical and pathologic characteristics.
Results: Of the 9 cases studied, 4 came from the northeast China and 5 from Beijing. Eight cases had a history of eating raw crabs. Most had symptoms including fever, chest discomfort or pain, and hemoptysis or rusty sputum. All had the following common pathologic features: formation of irregular lacunae or sinus tracts, Charcot-Leyden crystals, sometimes paragonimus body parts and/or eggs, and eosinophil infiltration in the adjacent tissues.
Conclusions: Paragonimiasis is not as uncommon as previously thought. The incidence is increasing in some cities due to movement of populations. The pathological diagnosis can be confirmed by finding paragonimus body parts and/or eggs. Diagnosis can also be made by correlation with other typical pathologic features, clinical history, immunologic findings and radiography. Paragonimiasis needs to be differentiated from pulmonary tuberculosis and cancer.