In an exclusive column for PRWeek, Kenny describes the fallout after the ex-Gordon Brown adviser gave details of criticisms of Number 10 aired by departmental comms figures at a two-day meeting in 2004.
Kenny, director of comms for the Department for Culture, Media and Sport at the time, describes being a victim of what McBride calls his first "proper dirty story".
She called the leaking, which resulted in her being named in The Sunday Times, "the worst weekend of my professional career".
Her piece comes ahead of the release of McBride's book, Power Trip, which has been serialised and includes details of smearing Labour ministers.
Kenny is currently group director of comms at HarperCollins, but will be leaving next month.