In the novel The Boy in the Striped Pajamas, why is Pavel not allowed to lay his hands on Bruno when he is injured despite the fact that Pavel is a doctor?

In Chapter 7, Pavel witnesses Bruno fall from a tire swing and runs out to help him. Pavel picks Bruno up and takes him inside where he immediately cleans and bandages Bruno's wounded knee. Pavel then tells Bruno he used to be a doctor before Bruno's mother walks into the kitchen. Bruno then overhears his mother telling Pavel not to tell the Commandant that he took care of Bruno's wounds. The reason Bruno's mother doesn't want the Commandant to know that Pavel laid his hands on Bruno is because of the prejudice against Jews. Pavel is a Jewish prisoner at Auschwitz. The German Nazis viewed the Jews with contempt and believed that they were dirty subhuman beings. Jews were compared to animals, and the thought of a filthy Jew touching a German boy was unthinkable to a Nazi. The Commandant would be disgusted and upset to hear that Pavel laid his hands on Bruno and probably would have killed Pavel after hearing this information.