Alfonza Lathan, 43, a college instructor of sociology who had been active in Arlington County community affairs, died Tuesday at Northern Virginia Doctors Hospital. He suffered from a kidney ailment.

He had started to teach at George Mason University this fall and earlier had taught at Northern Virginia Community College. He came here three years ago after teaching at the State University of New York in Oneonta.

Dr. Lathan worked for the Arlington County personnel department after coming here. At the time of his death, he was head of a consulting firm that he ran from his home in Arlington.

He was a member of the Arlington County Manpower Planning Council and the Arlington Committee of 100.

Born in Dolomite, Ala., Dr. Lathan served in the Army in Korea during the conflict there and then with the U.S. Air Force in England.

He later graduated from the University of New Mexico, where he also received a master's degree and a doctorate in sociology. he taught there and at Boston College.

He was a member of Disabled American Veterans.

He is survived by two children, Alfonza, of Oakland, Calif, and Brenda Jenkins, of Ypsilanti, Mich: a brother, Louis, of Detroit, and a sister, Martha LaGrande, of Springfield Gardens, N.Y.

The family suggests that expressions of sympathy may be in the form of contributions to the United Negro College Fund or the National Kidney Foundation.