When $\sigma$
is a quasi-definite moment functional with the
monic orthogonal polynomial system $\{P_{n}(x)\}_{n=0}^{\infty}$ , we consider a point masses perturbation $\tau$
of $\sigma$
given by $\tau :=\sigma +\lambda \sum_{l=1}^{m}\sum_{k=0}^{m_{l}}({(-1)^{k}u_{lk}}/{k!})\delta^{(k)}(x-c_{l})$ , where $\lambda,u_{lk}$ , and $c_l$ are
constants with $c_i\neq c_j$
for $i\neq j$ . That is, $\tau$
is a generalized Uvarov transform of
$\sigma$ satisfying $A(x)\tau = A(x)\sigma$ , where
$A(x) =\prod_{l=1}^{m}(x-c_{l})^{m_{l}+1}$ . We find necessary and
sufficient conditions for $\tau$
to be quasi-definite. We also
discuss various properties of monic orthogonal polynomial system
$\{R_{n}(x)\}_{n=0}^{\infty}$
relative to $\tau$
including
two examples.