Story highlights Mario Bosco has a rare condition known as panhypopituitarism

Bosco's pituitary gland was damaged in utero, so it doesn't produce enough growth hormones

At 43, he weighs 90 pounds and stands 4 feet 10 inches tall

Mario Bosco has been acting for more than 25 years, in spite of and because of his size. Last summer his memoir "From Hopeless to Hollywood" was released. The opinions in this article are his.

(CNN) My life began on the cold winter's night of January 19, 1973. What began as a normal birth and happy event turned into a long medical journey for me and my family.

It became apparent a few hours after I was born at Brooklyn Caledonia Hospital that I wasn't able to be nursed. I was crying, shaking all over and began convulsing. The doctor decided I needed to be transferred to Mount Sinai Hospital in New York City, where they were better equipped to handle my worsening condition.

I was transported by ambulance in an incubator and hooked up to an IV. My parents were told the IV was necessary until I could take in food on my own. Weeks of observation turned into months. Under the care of Dr. Ralph Moloshok, the chief of staff for the Department of Pediatric Endocrinology, the diagnostic process began.

When Mario Bosco was born, doctors were baffled by his medical condition.

My blood tests all came back normal, which baffled the doctors. After being subjected to invasive tests, injections, IVs, feeding tubes, etc., I was diagnosed with a thyroid problem and hypoglycemia. I was given the steroid cortisone acetate every three days.

By July, I started to eat. In August, after I'd been in the hospital for seven months, the doctor said I could finally go home. However, I would need three steroid injections a week. My father took on the job. I started to gain weight, but I wasn't growing.

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