I was wondering if there are travel insurances that cover people on kidney dialysis on a cruise ship?

I'm not sure what exactly your question refers to. Are you referring to coverage in case you need to cancel due to a kidney condition?

In general, no. Insurance does not normally cover "pre-existing" conditions. Those are medical conditions for which you've been treated within a specified period of time before you purchased the policy.

Sorry!

It's best you ask a travel agent this question, so you can be sure of getting the correct answer. This is too important of a question to just ask anyone.

Try this web site for Travelux travel insurance. I use them for my travels and they have a policy that covers medical stuff:

http://www.travelex.com/us/personal/travelinsurance.asp?content=tie


Check out this site also:
http://www.insuremytrip.com/

Dialysis at Sea is the largest provider of dialysis services aboard cruise ships. This is a great site for anyone who wants to cruise, but also requires dialysis. I had aconversation with a nurse who worked at sea on one of the cruises, and said it was wonderful to know that people could still travel while receiving treatment for their condition.

http://www.dialysisatsea.com/

You can buy travel insurance however, it will not cover pre-existing medical conditions but will cover you for new illnesses or injuries.