In patients with posthysterectomy prolapse of the vaginal vault, the posterior intravaginal slingplasty (posterior IVS, Tyco Healthcare, USA) has been suggested as an alternative to traditional vaginal vault suspensions. The goal of this technique is to recreate the uterosacral ligaments and to reinforce the rectovaginal fascia with the use of prosthetic material. We report the case of a 53-year-old woman with a history of 27 months of perineal suppurative discharge after she underwent a vaginal vault prolapse and rectocele repair using a posterior IVS (Tyco Healthcare®, USA). The IVS tape was reinforced by interposing a rectovaginal monofilament polypropylene mesh (Parietex®, Sofradim®, France). Imaging studies and surgical exploration confirmed infection of the IVS mesh with the formation of a gluteo-vaginal fistula while the rectovaginal mesh was intact.