The father of the former Medical School student suing the University and other defendants for $12 million reported last night that physicians at Medical School Health Center revised their original diagnosis of the student's case several days after making it.

The student, Walter E. Grueninger, a member of the Medical School Class of , has charged that he became totally blind as a result of improper treatment of an illness he suffered while at the University.

Contacted by phone last night, the elder Grueninger said the Medical Center originally diagnosed his son's case as ordinary pneumonia and sent him home. his son returned to the Center one or two days later," according to Mr. Grueninger, he was admitted to the Bent Brigham Hospital, and the diagnosis was changed to staphylococcus .

Grueninger stated that his son was confined to the hospital for five months and treated as a patient of the Medical Health Service, with a Health service doctor in charge of the case.

The University filed an "answer" to suit on May 18, 1960, 16 days after court received the case. The text of the University statement has been the by the court.

The plaintiff will base his right to sue Harvard on the ground that the Health service is a profit-making activity of the University, with its fee separate from tuition charges, a Boston newspaper has reported. An educational institution is normally subject to suit in Massachusetts.