Dear Sir,

I have read with great interest the report by Sileri et al. [1] recently published in Techniques in Coloproctology. This interesting report sheds light on a rare and unique complication of laparoscopic ventral rectopexy using biologic mesh: the spontaneous extrusion of the mesh after the procedure [2].

However, I have a few queries regarding points that were not clarified in the manuscript. First, although the report clearly described the details of the surgical technique and the clinical presentation of the patient after mesh extrusion, the possible reasons for such complication were not discussed. In figure 1, the mesh appeared to be completely intact with disruption of all anchoring sutures and tacks, and one wonders what mechanism caused the mesh to completely detach from the rectum and get extruded in such a way.

A plausible reason for this complication could be failure of physiological adhesions to form between the mesh and rectum. If no adhesions had developed to integrate and fix the mesh to the rectum, then the sutures would be of little value on their own in retaining the mesh in place. Mesh must integrate into the body in order to achieve permanent repair. This integration starts with an inflammatory reaction, followed by cellular and vascular infiltration and finally matrix remodeling. If this response was exaggerated, it could lead to excessive scaring and degradation of the mesh. On the other hand, with suboptimal foreign body response, which sometimes occurs with biologic meshes, failure of integration of the mesh can occur and eventually extrusion of the mesh [3].

Another important point that the report did not emphasize was the clinical outcome of the patient after mesh extrusion. Although the authors stated that the patient had no constipation for up to one year after mesh extrusion, no mention of further assessment for recurrence of the internal rectal prolapse either by clinical examination or evacuation proctography was made.

Furthermore, if the patient was symptom-free and the internal prolapse did not recur in the absence of the mesh, which is supposed to be the main factor preventing the recurrence of the prolapse, then the following question should be asked: what maintained the clinical improvement of the patient for an entire year after mesh extrusion.