“You see, before getting arrested,” Mr. Soltan said, “I was documenting crimes against justice, against humanity, against democracy in Egypt — trying to share my American principles with young Egyptians, hoping to build bridges between the two free generations. The very same youth that President Obama publicly praised following the Jan. 25 revolution.”

Later in the recording, Mr. Soltan said: “I ask my government — the government of the United States of America — is my life not worth anything to you? Has the life of American citizens become worthless, or is it because my name is Mohamed?” If so, he said later, “this sets a precedent for the plight of the hyphenated American to be ignored, completely.”

Addressing Mr. Obama directly, he added: “With your continued silence, you sir are saying that there are, in fact, different variations of American and my type — in this period, in this time — just happens to be the one that matters less, or not at all. I say this because your government moved mountains and sent a chartered plane to evacuate my fellow — blond-haired, blue-eyed — Americans, who were being detained by the same Egyptian military back in 2012.”

A doctor chosen by Mr. Soltan’s mother was able to gain access to him in April, and evaluate the toll the hunger strike was taking on his body, thanks to the efforts of the United States Embassy in Cairo, The Guardian reported last month.

After Mr. Soltan was shot in the arm during the Aug. 14 raid that cost hundreds of protesters their lives, he had directed a bitter tweet at the American president he said he was proud to have campaigned for in Ohio before the 2008 election: “@BarackObama The Egyptian army put a bullet that fractured my arm that I paid 4 w/my tax dollars! #RiddleMeThat.”