39The Court observes that the existence of an act adversely affecting the official concerned within the meaning of Articles 90(2) and 91(1) of the Staff Regulations is an essential condition for the admissibility of any action brought by officials against the institution by which they are employed (see, most recently, the judgment of the Court of First Instance in T-50/92Fiorarti ν Parliament [1993] ECR ΙΙ-555).