Does low blood platelets mean leukemia?

Hi, someone please help. My husband's platelet count is at 53,000 and we are worried. He may have to have a bone marrow done. Is this difficult? We don't know much about his father but it does not run on his mom's side. We are hoping that it is just ITP, but please give us the odds of it being Leukemia. We are scared. I'm not ready to loose him, hes my soulmate and we've only been married alittle over a year. Thanks for your time, we appreciate any input we can get. His next doc's visit is in about 5 weeks. Thanks. :-(