Allergens could trigger an allergic vasculitis. That would explain the symptoms.
He has no history of allergies or asthma. Most importantly, none of his symptoms remotely resemble an allergic reaction.
The more infections we rule out, the more likely it is that it's not an infection.
The more infections we rule out, the more likely it is that it's not an infection. [SEP] He has no history of allergies or asthma. Most importantly, none of his symptoms remotely resemble an allergic reaction. [SEP] Allergens could trigger an allergic vasculitis. That would explain the symptoms.