5-Year-Old Dies Of Extremely Rare Condition Days After Being Brought to Hospital

A 5-year-old boy -- Justin Vu -- died last week from a medical condition so rare, less than 500 cases have ever been diagnosed worldwide.

Justin died July 8 from systemic capillary leak syndrome, also called Clarkson's disease, an extremely uncommon disorder in which plasma suddenly leaks from blood vessels into surrounding tissues. He died at Randall Children's Hospital in Portland, just five days after he first began feeling sick, according to KGW News.

His family was on a vacation from Colorado ... visiting the Pacific Northwest when, all of a sudden, Justin developed a stomachache. His mother, Terese Peden, initially thought it was pretty normal until the 5-year-old began vomiting throughout the night.

Justin's mom rushed him to the hospital ... where doctors struggled to find a diagnosis for the boy's condition. After two days in the hospital, he was put on life support and doctors told his mom he had a "50/50 chance" of survival.

Eventually, doctors found the likely cause of the boy's symptoms -- Clarkson's disease. According to the Cleveland Clinic, there is no cure for the rare condition, and if capillary leak syndrome isn't treated promptly, your blood pressure drops rapidly, leading to organ failure and even death. It is unknown exactly what causes the condition.

"We were informed that his body was dying, and those medications were not going to be enough," his mom said.

Doctors tried again to save Justin, but were unsuccessful ... and Justin died 5 days after being hospitalized.

Now, the Colorado family is trying to raise awareness for the rare condition, with Justin's father -- Viet Vu -- saying on Facebook, "If my son's story can help even one person, it would make all of us happy."

Justin was only 5.