Preheat oven to 375 degrees F. Lightly grease a baking sheet
or line it with parchment paper. Set aside.
In a mixing bowl
, beat cream cheese
at medium speed with an electric mixer until creamy. Add egg yolk and 1/4 cup
confectioners' sugar. Beat until well mixed. Set aside.
Remove breadstick dough from can. Unroll and separate dough into two rectangles. Place dough rectangles horizontally on prepared baking sheet that is positioned vertically to baker. (Dough rectangles should abut horizontally in center of baking sheet.) Press seam together to seal.
Spoon cream-cheese mixture onto center third of dough.
Wash, drain, and dry blueberries. Sprinkle blueberries over cream-cheese mixture.
Separate dough at perforations up to cream-cheese mixture, slightly stretching dough strips. Beginning at top edge of dough, braid strips to cover filling. Tuck last two ends under at bottom of loaf.
In a small bowl
, beat egg white and water with a fork until blended to form an egg wash. Brush egg wash over braided loaf.
Bake until golden brown, approximately 20 minutes. Cool for at least 45 minutes, or as long as you can stand it, on baking sheet before serving.
In another small bowl, combine remaining 1 cup confectioners' sugar and orange juice, whisking until smooth. Drizzle glaze over braided loaf before serving. For best presentation, slice using an electric knife or a serrated knife.