  It has been known for some time that the usual $q$-entropy $S_q^{(n)}$ cannot
be shown to converge to the continuous case. In [Phys. Rev. E 97 (2018)
012104], we have shown that the discrete $q$-entropy $\widetilde{S}_q^{(n)}$
converges to the continuous case when the total number of states are properly
taken into account in terms of a convergence factor. Ou and Abe [Phys. Rev. E
97, (2018) 066101, arXiv:1801.03035] noted that this form of the discrete
$q$-entropy does not conform to the Shannon-Khinchin expandability axiom. As a
reply, we note that the fulfillment or not of the expandability property by the
discrete $q$-entropy strongly depends on the origin of the convergence factor,
presenting an example in which $\widetilde{S}_q^{(n)}$ is expandable.
