Allergies can cost you -- and the price can be more than money, itchy eyes, a runny nose and general discomfort. They can cost you productive hours at work, sunny days outdoors or even a household pet.
But for some, allergies can go beyond the normal range of discomfort, with serious consequences.
They cost Ray Sanders much more than he expected: vision in his left eye.
Sanders, 17, had been troubled by allergic symptoms for the past year. These symptoms escalated until about a month ago, during a trip to the barber, when Ray complained to his mother that he could not see out of his left eye.
"I could feel the pressure over my head, and then I would lose total sight in my left eye," Sanders told ABC13, KTRK, in Houston.
Initially, Sanders' doctors thought he was having vision problems because of a torn retina, since Sanders is heavily involved in athletics. But his mother, Donna Sanders, had a hunch that the problem was something else.
"I said, 'I don't know, I'm not a doctor, I'm just a mother,' but I think he has a sinus infection," Sanders said.
Sanders was diagnosed with allergic fungal sinusitis, a sinus condition that can occasionally have dramatic negative side effects.
"We don't really know the cause of allergic fungal sinusitis," said Ralph Metson, a sinus surgeon at the Massachusetts Eye and Ear Infirmary and a professor at the Harvard Medical School. "It is pretty rare."
Although Metson said he sees a few dozen people with the infection each year, it is very uncommon to have dramatic symptoms such as vision loss or a brain infection. Martin Citardi, the doctor at Memorial Hermann-TMC in Houston, who treated Sanders, told KTKR that he has seen only a handful of such cases over the course of his career.
The sinuses are hollow passages to the face and head that drain mucus through pinpoint openings into the nose. If these passages become blocked, mucus builds up, forming the perfect breeding ground for bacteria.
Occasionally, fungi will breed in the built-up mucus instead of bacteria. Allergic fungi can be particularly damaging, eroding the surrounding bone tissue. If the bones that protect the optic nerves are worn down, then the infected mucus can put pressure on those nerves and impair vision.
Bone erosion can occur in the direction of the brain as well, causing brain infections.
But no one knows why some people are more likely to get a fungal infection rather than a bacterial infection, nor is it clear whether the fungus is the cause or the result of the blockage.
And allergies may not have anything to do with allergic fungal sinusitis, Metson said. But nasal and sinus irritation from allergies can leave a person more susceptible to the infection. And Houston is one of the most challenging cities to live in if you have allergies, according to the Asthma and Allergy Foundation of America.
Allergic fungal sinusitis can cause permanent damage if it is not caught in time, and Sanders could have lost the sight in both of his eyes permanently.
Within a week of experiencing vision loss, Sanders underwent surgery to remove the infection, which his mother said had wrapped itself around the optic nerve in his left eye.
"He was scared," Donna Sanders said. "We did a lot of praying."