They had tissue specimens of mesh removal procedures between 2011-2012 for symptomatic complications which were examined by microscopy (H&E) and immunohistochemical staining for versican, (hyaluronan-binding protein a/w inflammation and elastin breakdown), hyaluronan (HA), and α-SMA (smooth muscle protein a/w inflammation and myofibroblast marker). Comparison was performed to control specimens obtained from excess tissue of POP or SUI surgery. Their result found the explant cases (n=29) included 17 slings, 4 abdominal implants, and 8 vaginal implants. Indications for surgical removal were urinary obstruction (13), pain (20), and erosion/exposure (17). Compared to control tissues (n=9), vaginal tissue from mesh removal exhibited strong HA and versican staining adjacent to mesh fibers (figure 1). ECM of explant case specimen showed enrichment of HA. Giant cells containing nuclei that were in contact with mesh appeared negative for HA but ECM between lymphocytes was rich in HA. Occasionally, α-SMA positive cells co-localized with versican in characteristic fibrous capsule surrounding mesh fibers. Associated nerves along mesh fibers and within the fibrous capsule stained strongly for versican.
In conclusion the vaginal tissue in women with symptomatic mesh complications reflected changes in ECM components versican, HA, and α-SMA and suggests that some capsular cells around mesh fibers differentiate into myofibroblasts. Accumulation of space occupying deposits of versican and HA around nerves offers a possible mechanism of pain and merits further investigation. Their data might provide further evidence of the fibrotic and inflammatory processes in mesh complications.
Presented by: Katherine Amin, MD
Authors: Katherine Amin MD¹, Sarah Adelstein MD¹, Stephen P Evanko PhD², Alvaro Lucioni MD¹, Kathleen Kobashi MD¹, Thomas Wight PhD² and Una Lee MD¹
1.Virginia Mason Medical Center, Department of Urology, Seattle, WA;
2.Virginia Mason Medical Center, Benaroya Research Institute Wilske Translational Research, Seattle, WA
Written by: Bilal Farhan, MD, Female Urology Fellow and Voiding Dysfunction, Department of Urology, University of California, Irvine at the Society of Urodynamics, Female Pelvic Medicine & Urogenital Reconstruction Winter Meeting (SUFU 2018), February 27-March 3, 2018, Austin, Texas