An American in Paris fashion. The Southern accent of designer Patrick Kelly

It's a long way from the farm in Vicksburg, Miss., where he was born, to the pinnacle of high fashion in Paris, but Patrick Kelly has made his way in record time. As a child he was always losing buttons from his clothes. His grandmother, who gave up trying to match them, would replace missing buttons with whatever substitute she could find. ``People used to laugh at me, 'cause all my buttons were different,'' Mr. Kelly says.

They don't laugh anymore. In fact, mismatched buttons are now part of the trademark for his unique, fun-loving style, which has charmed the fashion world.

Only three years after presenting his first ready-to-wear collection, Kelly has become the first American ever to be elected to the very selective, 44-member French designers' club known as the ``Chambre.'' The young designer joins the likes of Yves Saint Laurent, Chanel. Christian Dior, Christian Lacroix, Montana, and Courreges. Few foreigners have been so honored.

Kelly celebrated the occasion late last month with a showing of his small collection of made-to-order winter designs. Styles ranged from the sublime - tailored suits and dresses with longer hemlines, mostly in somber gray flannel, and flowing crepe pants - to the ridiculous - motorcycle-helmet hats, lopsided pockets, scoop necklines trimmed with huge gardenias, and, of course, an abundance of buttons.

Sonia Rykiel, one of France's best-known couturiers, recalls French designers' early reservations about Kelly's talent. ``All we knew was that he did his [button and bow] patchwork thing very well,'' she said in a phone interview. ``Now, a recognizable `Kelly woman' ... has clearly emerged, and Kelly has proved that he is not just a flash in the pan.''

Like his grandmother, Kelly has always been one to make do with whatever is at hand. He first entered the rag trade when he moved to Atlanta at age 18 and collected old clothes for a charity group. Some were expensive castoffs - items with Chanel labels, or trimmed with silver fox - so he patched them up and sold his hip fashions to Atlanta socialites.

Kelly later moved to New York to study at Parsons Designer School. In 1981 he arrived in Paris, nearly broke, and started making coats, for the simple reason that ``coats were the only thing people would try on outside in winter,'' he said in a recent interview. He turned out 15 coats a day in a one-room apartment, until one of his satisfied customers introduced him to Francoise Chassagnac, a buyer in a chic Paris boutique, Victoire.

``Patrick landed like a bomb in my shop in 1985,'' recalls Ms. Chassagnac. ``He was so gay and so full of energy, and so were his clothes, even though they weren't even finished.'' The dresses, fashioned from cotton jersey tube cloth, had cutout circles for arms, and no hems.

Chassagnac bought them all and ordered more. She loaned Kelly a workshop and put up the money for his first ready-to-wear show, in the spring of 1985.

Kelly's designs belie his Southern Baptist past, but draw heavily on black and pop culture. His ready-to-wear dresses in shiny fabrics with elaborate draping at the hips and waist mostly come in seething hot colors. Bandannas, jungle prints, and polka dots are among his favorite motifs. Zany Kelly trimmings include buttons, plastic hearts, watermelons or black baby dolls pinned to lapels, and huge baby bows.

Wearing a pony tail, pink basketball shoes tried with red laces, oversize coveralls, and a baseball cap, Kelly looks more at home on his skateboard than at a fashion show. On special occasions, he dons a Saint Laurent tuxedo jacket, bought on sale, over his overalls.

All of which has endeared the expatriate American to the high-fashion Parisians. He charms the laid-back tout Paris with his buoyant laughter, though his pidgin French, distorted by his deep Southern drawl, often left them baffled. He fixes them fried chicken and hominy grit dinners, and hands out hundreds of black doll pins every week, while riding his skateboard in the streets of Paris.

The Mississippi farm boy's one-room sweatshop is now an international enterprise. Last July, Kelly turned over the Licensing of h is clothes to Warnaco Inc., the American apparel company. He has 10 distributors in France and sales points in Germany, Belgium, Britain, Italy, and Japan.

The designer's prices have kept pace with his soaring reputation. Two years ago, a little Patrick Kelly dress sold for about $100 at the Victoire; today a white cotton pique dress costs $345. Still, Kelly says he wants to keep a broad range of prices to suit working women and show-biz people alike. Although Martha's, the deluxe New York shop, sells a $10,000 gray-and-black leopard jump suit by the designer, Saks and Bergdorf Goodman in New York carry $35 Kelly T-shirt dresses.

Still a scrounger at heart, Kelly continues to frequent Paris flea markets in search of antique clothes, trinkets, and inspiration. He delights in taking important American buyers on shopping sprees at Barbes, a seedy district in northern Paris. The neighborhood has particular appeal to the city's immigrant population - and to Kelly, who likes to incorporate street fashion into his designs. Motorcycle jackets and high leather boots are an important part of his fall ready-to-wear collection.

No wonder Christian Lacroix, France's hottest designer of the moment, offers the American the highest possible praise, saying: ``Kelly's clothes are Parisian in spirit.''