Daniel Johnston, a singer-songwriter and visual artist whose childlike, haunted songs brought him acclaim as one of America’s most gifted outsider voices, was found dead on Wednesday morning at his home in Waller, Tex., outside Houston. He was 58.

His brother and manager, Dick, said in an interview that Mr. Johnston had probably died overnight. He did not specify the cause.

Mr. Johnston had been released from a hospital on Tuesday after being treated for kidney problems. “He was still productive, writing songs and drawing, and was just annoyed by his health more than anything,” his brother said. “It was just one thing after another.”