On the isomorphism of categories of presheaves

Question

I'm very sorry for my silly doubt. Let $\widehat{\mathfrak{C}}:=[\mathfrak{C}^{op},{\bf Set}]$ and $\widehat{\mathfrak{D}}:=[\mathfrak{D}^{op},{\bf Set}]$ be two category of set-valued presheaves. Assume that $\widehat{\mathfrak{C}}$ is isomorphic to $\widehat{\mathfrak{D}}$. Is it possible to derive some conclusion about the possible relationship between $\mathfrak{C}$ and $\mathfrak{D}$? For instance, are $\mathfrak{C}$ and $\mathfrak{D}$ isomorphic (or equivalent)?