LONDON, England (CNN) -- Fantasy author Terry Pratchett has admitted that he has been diagnosed with a rare form of Alzheimer's disease -- but says he plans to continue writing his multi-million selling Discworld books.
Terry Pratchett, whose books have sold more than 45 million copies worldwide in 33 languages.
Pratchett, 59 -- whose books have, according to his Web site, sold more than 45 million copies worldwide in 33 languages -- suffered what he called a "phantom stroke" earlier this year.
In a statement titled "an embuggerance" on the Web site of Discworld illustrator Paul Kidby, Pratchett says that he has been diagnosed with what he terms "a very rare form of early onset Alzheimer's."
"I would have liked to keep this one quiet for a little while, but because of upcoming conventions and of course the need to keep my publishers informed, it seems to me unfair to withhold the news," says Pratchett, who has a strong following among fans of fantasy fiction.
"All other things being equal, I expect to meet most current and, as far as possible, future commitments but will discuss things with the various organisers," he continues.
"Frankly, I would prefer it if people kept things cheerful, because I think there's time for at least a few more books yet."
Pratchett adds that work is continuing on his next book "Nation" and that the "basic notes are already being laid down for Unseen Academicals."
In a P.S. he adds that "I would just like to draw attention to everyone reading the above that this should be interpreted as 'I am not dead'. I will, of course, be dead at some future point, as will everybody else.
"I know it's a very human thing to say 'Is there anything I can do', but in this case I would only entertain offers from very high-end experts in brain chemistry."
Pratchett's Discworld novels, of which 36 have been published to date, are set in a fantasy universe through which the author satirizes modern-day life.
He says in a statement on his own Web site that the series "started out as a parody of all the fantasy that was around in the big boom of the early '80s, then turned into a satire on just about everything, and even I don't know what it is now."
Pratchett, who began writing while a provincial newspaper journalist in the 1960s, received the Order of the British Empire "for services to literature" from the Prince of Wales in 1998. E-mail to a friend