A nanny has pleaded not guilty in the stabbing deaths of two children at their upscale Manhattan home.

Yoselyn Ortega was arraigned Wednesday at a hospital where she has been treated for self-inflicted stab wounds.

Six-year-old Lucia Krim and her 2-year-old brother, Leo, were killed Oct. 25 in their Upper West Side apartment.

Their mother found them when she came home with the victims' 3-year-old sister.