Paragonimiasis in a person whose symptoms were shown 22 years after emigrating to Japan from Laos.

We report a patient, a 52-year-old man from Laos, who had come to Japan at 30 years of age, but had maintained a habit of eating raw freshwater crabs. The patient visited a physician for left chest pain in January 2007. Infiltration and mass-like shadows were noted in the left superior and inferior lobes on chest X-ray. Diagnosis could not be made by bronchial brushing, but eggs were present in sputum cytology 3 days after bronchoscopy. Therefore, paragonimiasis was diagnosed. The peripheral eosinophil count had increased to 2550/μl and the serum IgE level was elevated, at 71000 IU/ml. Multiple-dot enzyme-linked immunosorbent assay (ELISA) for specific IgG antibodies in serum was positive for Paragonimus westermani and P. miyazakii. Paragonimiasis may have been caused by the style of Laotian cooking without heating. Because the habit of eating raw freshwater crabs is common in Laos, Laos is one of the countries where paragonimiasis is prevalent. For patients from Laos with lung diseases, differentiation including paragonimiasis is required.