November 29, 1986

Mildred Johnson pulled a folder from the file drawer, arranged her face in a neutral but kindly configuration and led a young man into her office to deliver some terrifying news. ''Your test was positive,'' Ms. Johnson told her client, who was known to her only by a three-digit identification number, ''but that does not necessarily mean you have AIDS.'' For the next hour and a half, as day turned to dusk outside the windows, Ms. Johnson answered and asked questions, counseled and comforted, as she has in the month since the New York City Health Department opened its first center to offer AIDS antibody tests on an anonymous basis. Anxiety Over Tests The test measures the presence of antibodies to the virus causing acquired immune deficiency syndrome. A positive result indicates that the person may be infected with the virus and can pass it to others through sexual intercourse or the exchange of blood.

The United States Government set up a major ''sting'' operation late last year, complete with a fraudulent bank account, to catch arms merchants dealing with Iran, according to court documents, bankers and officials involved in the case. The operation occurred at the same time high Administration officials were secretly shipping arms to Iran. It resulted in 17 indictments last spring, and a Federal trial is proceeding in the Southern District of New York in Manhattan. The defendants, pleading not guilty, say they believed they would receive the approval of high Administration officials to sell arms to Iran. Another defense contention is that the Government's chief sting operative, Cyrus Hashemi, an Iranian, was at the same time involved in shipping the covert arms to Iran for the Administration. Mr. Hashemi died suddenly in London last July in what his brother said were suspicious circumstances.

The Administration is going ahead with its program of drug testing of Federal employees despite recent court decisions that such widespread random tests are unconstitutional and despite reservations among some top advisers to the White House. The Office of Personnel Management today distributed to all agency heads and Cabinet officers copies of its new guidelines on illegal drug use by Federal workers. The regulations were drafted in response to President Reagan's executive order Sept. 15 calling for a ''drug-free workplace'' and requiring each agency head to establish a program to test for use of illegal drugs by employees in sensitive positions. Effective Immediately The rules, which were written by the personnel management agency in conjunction with the Justice Department and the Department of Health and Human Services, will become effective immediately, according to James Lafferty, a spokesman at the agency.

Two weeks after leading Brazil's centrist governing party to a stunning victory in midterm elections, President Jose Sarney has suddenly become the target of bitter recriminations over his decision to start lifting a nine-month-old price freeze. In the first violent anti-Government demonstrations since military rule ended here last year, heavily armed policemen clashed Thursday in Brasilia with several thousand workers and students protesting price increases. Leaders of the governing Brazilian Democratic Movement have also loudly criticized the new economic measures, which were announced just six days after the Nov. 15 congressional and gubernatorial elections. Caught in the crossfire, the country's Finance Minister, Dilson Funaro, offered his resignation Wednesday, but it was turned down by the President.

Pandemonium paid a visit backstage yesterday at Radio City Music Hall. George, a camel, stepped on the foot of a Rockettte; six sheep came off the elevator as three kings bearing gifts got on; human Christmas trees bumped into eight maids-a-milking at the water cooler, and an elf came down with the flu. The day after Thanksgiving, as Christmas mania came to Manhattan, the cast and crew of ''The Magnificent Christmas Spectacular'' had to pick up the pace, doing four shows to sold-out, 5,874-seat houses. Scrooge pushed past Mary No. 1 and Joseph No. 2 in the wings without so much as an ''excuse me.'' Typical.