I hope somebody can help me please!!

We suspect that our 4 year old girl is allergic to mosqito bites. It is not just the regular itchiness and swelling, but whenever she has a bite she is swollen like a football around that area for around 4 days... :'(

Now we really would like to get her tested for mosqito allergy and I already called the Hong Kong Sanatorium in Happy Valley. However, they don't test for that in this hospital and the lady on te phone did not know where to go for that either :( Really need help on that as I want to get it treated during the cold months.

Thanks a lot!