National Institutes of Health officials are reportedly looking into the possibility of prosecuting columnists Jack Anderson and Dale Van Atta for quoting from the NIH medical record of lawyer Roy Cohn in their column Friday. Anderson and Van Atta said in the column that Cohn had been treated at NIH for AIDS (acquired immune deficiency syndrome) and gave details from the record such as his admitting diagnosis, the name of his NIH doctor and the dose he received of an experimental drug being used for AIDS patients.

John Fletcher, staff ethicist at the NIH Clinical Center, said NIH officials did not know who leaked the medical record, and that NIH investigator Howard Hyatt has been assigned to try to find out. He said Anderson and Van Atta may have violated the federal Privacy Act and a Maryland state law governing confidentiality of hospital records. He said he had told Van Atta in a telephone conversation "not to be surprised" if NIH brought charges.

Van Atta said he "would welcome the suit" because he thinks it would set a precedent allowing journalists to quote from medical records, especially those of public figures. Van Atta said, "If I had all the records of all the people that have AIDS, I wouldn't print a word of it. But Roy Cohn is a special case because he had made a public issue of his dying." He said Cohn tried to resist being disbarred by announcing that he was dying of liver cancer. Land Mines . . .

Following "Diamond Don" Regan's unpopular remarks on whether the women of America are prepared to give up their jewelry in the name of sanctions against South Africa, administration officials are watching their steps.

Take Secretary of Defense Caspar W. Weinberger, who invited a small group of journalists to lunch in his dining room at the Pentagon a few days after the White House chief of staff launched the rhetorical question heard 'round the world. The guests munched and asked about arms control, the Strategic Defense Initiative and the U.S. role in Bolivia's war on drugs. Eventually, columnist Carl Rowan turned the talk to South Africa, asking Weinberger to discuss the controversial question of how much we need rely on South Africa for strategic minerals.

Weinberger archly turned to Rowan and asked a rhetorical question of his own. "Are you trying to get me to talk about diamonds, Carl?" Dining Out . . .

A little known entry in a store of Washington artifacts is a guest book kept by Kazan, a 6-year-old restaurant in McLean. Guests who come to sup on Turkish and continental fare are invited to sign the book at the end of the evening. Many of Washington's ebullient diners comment on their meals.

Most comments are of the what-a-lovely-evening sort. Attorney General Edwin Meese III, for example, wrote "Thank you for a great dinner in very pleasant surroundings." From syndicated columnist Jack Anderson, "A very delicious meal and a very enjoyable experience."

Most original was former national security affairs adviser Zbigniew Brzezinski, who addressed proprietor Zeynel Uzun by name and wrote, "I have always admired Turks as great warriors. But now I also know that they are also gourmets." Safety Crew . . .

New chief of the Occupational Safety and Health Administration John A. Pendergrass has announced the appointment of two deputy assistant secretaries of Labor for OSHA: Candace Strother, a former White House staff assistant has worked for syndicated columnists Rowland Evans and Robert Novak and as director of broadcast liaison for the Heritage Foundation; and Frank White, an attorney at Labor since 1971 in OSHA, the Mine Safety and Health Administration and the Black Lung Benefits Program. Up the Ladder . . .

President Reagan announced Friday that he will nominate Louis F. Laun assistant secretary of commerce for international economic policy, succeeding Joseph F. Dennin. Laun, former president of the American Paper Institute, is a deputy assistant secretary at the Commerce Department.

Reagan also said he will nominate Dennis Kux, a career Foreign Service officer, as ambassador to the Republic of Ivory Coast, succeeding Robert Hopkins Miller. From the Coast . . .

Ambassadorial nominations are flying fast and furious this summer, and California cognoscenti suggest that Iraq will soon be added to the list. Wadie P. Deddeh, 65, a California state senator from the San Deigo area, flew to Washington last week to discuss his future.

Deddeh's office says only that he is being interviewed for an opening somewhere in the Middle East.