  We show that if $A$ is a unital $C^*$-algebra and $B$ is a Cuntz-Krieger
algebra for which $A\otimes\mathbb{K} \cong B\otimes\mathbb{K}$, then $A$ is a
Cuntz-Krieger algebra. Consequently, corners of Cuntz-Krieger algebras are
Cuntz-Krieger algebras.
