My roommate has selective immunoglobulin IgA deficiency, and if she gets sick, she usually gets the worst that the sickness has to offer. Her immune system is very weak, so once she gets infected with something, it takes her a long time to shake it off.
She once got a sinus infection that led to acute asthma. Everyone with a sinus infection has trouble breathing, and some develop a chest cough, but hers was intense.
She got an ear infection that wound up causing temporary hearing loss. In people with her condition, antibiotics don’t work so well.