>The patient who I met have tropical eosinophilic pneumonia and
>bronchial asthma.
>1) How can I find that the filariasis is the cause ?
>2) Is The filariasis a trigger for bronchial asthma?
1) The gold standard for this diagnosis is the Circulating Filarial
Antigen blood test (CFA) to detect the presence of the parasite.
2) Yes, it can be accompanied with asthma / pulmonary eosinophilia.
Just curious--are you posting from Africa?
Disclaimer: I am not a doctor, nor do I play one on TV.