Pizza, macaroni and cheese and peanut butter and jelly sandwiches are usually the diets of picky toddlers, but 6-year-old Tyler Trovato could not eat anything else even if he wanted to.

Trovato, who lives in New York, suffers from a rare food allergy condition, and as a result, he can only eat a handful of foods without severe vomiting, lethargy and diarrhea. The condition is called food protein induced enterocolitis syndrome (FPIES) and is extremely difficult to diagnose. Typical allergy tests will come up negative, so it took Trovato and his family more than a year to figure out exactly what he was suffering from.

“The main problem happened when we started introducing the baby foods,” said Trovato’s mother, Jennifer Trovato, to ABC News explaining when she recognized something was wrong. “He was vomiting, sometimes 15, 20 times. He would lay there; he was lethargic. I would hold him in my arms, and I just didn’t know what to do.”

Jennifer also explained they did not know it was an allergy at first because symptoms emerged several hours after eating a harmful food. Finally, Tyler was diagnosed with FPIES when he was 18 months old, which in turn helped the family control his allergic reactions and hospital visits.

To figure out what foods he was allergic to, Jennifer had to have Tyler eat a variety of food and watch for the symptoms. During those grueling hospital visits, Tyler suffered from vomiting, diarrhea and sometimes hypovolemic shock, which occurs after the body loses too much fluid and blood.

"It was stressful for us as parents," Jennifer said. "We knew there was something wrong.”

Luckily, Tyler’s immunity has grown since he was a baby and he can now eat a small variety of different foods.

"He's come a really long way," his mother said. "He can eat wheat, cheese and milk products, plus corn and apples."

According to doctors, children usually grow out of the condition within a couple years, which will be a relief for both Jennifer and Tyler. For now, Tyler is participating in studies to help fix the condition and Jennifer is working to raise awareness of FPIES so other children can be diagnosed quicker.

Sources: Daily News, Daily Mail