Stay with the traditional 4, it will not hurt to know that extra one exist, but just stay with the 4 main one.
A little review for the other people about Hypersensitivity
Type 1
Something that normally wold not give you a problem, like dust,pet dander, trees, etc. Your body for some reason gets a little crazy and says NO I DO NOT LIKE THIS DUDE.
So the second time you are in contact you create an allergic reaction.
Lets say you are In party and you see a lady that everyone think is the best, then for some reason you do not like her. Next time when you see the lady your Buddy IgE says to you dude thats the chick you do not like and you just burst into a living hell
That guy has serious issues
Type 2
You create antibodies that go crazy on you, and they start attacking your own cells
.
Type 3
You have and org with 3 people
Antigen
Antibody
Compleme
They are together and they just go and sit in a specific area, then someone passing by, looks at them and say hey hey whats going on there and start destroying the tissue involve.
Type 4
Today is Saturday And I'm kind of lazy
here is a link in case you guys did not understood what I try to explain.
Hypersensitivity
PS please correct anything you see wrong in my explications, I do not mind better for you and the other people, and serve you as a little review.