The 20-year-old Dubliner has recently been deputising for the injured Jake Buxton at centre-back for the Rams.
His international call comes on the back of three of his club-mates - fellow centre-half Richard Keogh, midfielder Jeff Hendrick and striker Conor Sammon - being drafted into the senior Ireland squad.
"It's pleasing to see another one of our players receive international recognition and after battling back from a few long-term injuries already in his career. Mark thoroughly deserves this call-up," said Derby boss Nigel Clough.
