At 42 inches tall, Blake Loudenber stands about as high as the average 5-year-old.

The problem is, he turns 9 this month.

With closing growth plates threatening to keep him 3 1/2-feet tall the rest of his life, Blake is in a race against his own body to find a new kidney.

The second-grader at Beiriger Elementary School in Griffith was born with polycystic kidney disease. He was put on dialysis at 3 weeks old after doctors expected he would not live three days, said his grandmother Cindy Loudenber.

He had a kidney transplant at 2, but his body rejected it, leaving him on a donor list ever since. He was put on growth hormone injections when it became clear he was not growing at the usual rate, but his body had severe reactions.

Blake spends 11 hours a night on peritoneal dialysis, which is done on a machine at home, and takes a host of medications and injections to stay healthy, his grandmother said.

Still, he has never swam in a pool or even splashed around in a bath tub because he can't submerge his stomach catheter.

Doctors at the University of Chicago called in Blake on March 10, thinking they had a kidney for him. Instead of leaving with a new organ, he left disappointed because they determined it would not be a good fit.

His grandmother said he was embarrassed. He missed a classmate's birthday party for the supposed surgery, and he was anxious at the thought of explaining that the surgery fell through.

Blake gets emotional about his illness.

"He doesn't want the attention," his grandmother said.

From the looks of it, he is an average boy who likes baseball and gym class. He groans when it's time to do homework, preferring to bounce a ball and play in the yard.

Blake's mom, Candy Loudenber, said her son is a jokester.

"He always makes everyone smile," she said.

Blake has web pages in his name on Facebook, CaringBridge and YouTube. There's even an ad on Craigslist, titled "Kidney for 8-year-old boy."

Anyone who wants to be tested as a donor can contact the kidney transplant program at University of Chicago at (773) 702-1000.