Considering hidradenitis suppurativa as a bacterial biofilm disease

Hidradenitis suppurativa (HS) is a chronic inflammatory disease of the skin that results in a relapsing course of painful draining sinuses and abscesses. The disease manifests largely in the apocrine-gland bearing regions of the body (axillary, inguinal and anogenital areas) and is usually treated by antibiotics and/or surgery. The exact pathogenesis of HS is still in dispute but likely multifactorial; in some instances, a genetic component has been demonstrated. While much attention has been given to the cellular and molecular biology of the host tissues affected by HS, rather less has been given to the bacteria involved (most commonly Staphylococci or Streptococci). We note that the characteristics of HS comport exactly with the features of bacterial biofilm-based infections, and examined a case where HS of the buttocks had progressed to an advanced stage. Physical examination of the sinus tracks at surgery revealed a mucinous accumulation consistent with biofilm formation. Confocal microscopic examination using Live/Dead staining revealed clusters of bacteria attached to the sinus luminal surfaces. The paradigmatic clinical features of HS, coupled with the adherent bacterial communities we observe here, suggest that HS should be considered in the expanding spectrum of bacterial biofilm-based disorders

Bacterial biofilms on implanted suture material are a cause of surgical site infection

Background: Surgical site infection (SSI) has been estimated to occur in up to 5% of all procedures, accounting for up to 0.5% of all hospital costs. Bacterial biofilms residing on implanted foreign bodies have been implicated as contributing or causative factors in a wide variety of infectious scenarios, but little consideration has been given to the potential for implanted, submerged suture material to act as a host for biofilm and thus serve as a nidus of infection. Methods: We report a series of 15 patients who underwent open Roux-en-Y gastric bypass (with musculofascial closure with permanent, multifilament sutures) who developed longstanding and refractory SSIs in the abdominal wall. Explanted suture material at subsequent exploration was examined for biofilm with confocal laser-scanning microscopy (CLSM) and fluorescence in situ hybridization (FISH). Results: All 15 patients at re-exploration were found to have gross evidence of a "slimy" matrix or dense reactive granulation tissue localized to the implanted sutures. Confocal laser-scanning microscopy revealed abundant biofilm present on all sutures examined; FISH was able to identify the presence of specific pathogens in the biofilm. Complete removal of the foreign bodies (and attendant biofilms) resulted in all cases in cure of the SSI. Conclusion: Bacterial biofilms on implanted suture material can manifest as persistent surgical site infections that require complete removal of the underlying foreign body substrata for resolution

Direct demonstration of bacterial biofilms on prosthetic mesh after ventral herniorrhaphy

Background: Prosthetic mesh is employed routinely in the treatment of ventral and parastomal hernias, but its use can lead to major complications, including infection, extrusion, and fistula. Bacterial biofilms have been posited to play a role in mesh-related infection, but although bacteria have been noted to form biofilms on mesh surfaces in vitro, they have never been visualized directly in biofilms on mesh recovered from patients experiencing infectious complications.Methods: Five patients who developed complications after ventral hernia repair with prosthetic mesh were operated on again. Explanted mesh was examined for biofilm with confocal laser scanning microscopy (CLSM) and fluorescence in situ hybridization (FISH). In two cases, a novel molecular assay (the Ibis T5000) was used to characterize the biofilm-forming bacteria.Results: The CLSM examination demonstrated adherent biofilms on mesh surfaces in all five patients. Biofilms also were noted on investing fibrous tissue. The FISH study was able to discriminate between bacterial species in polymicrobial biofilms. In two patients the Ibis T5000 detected more species of constituent biofilm bacteria than did standard culture. Removal of the mesh and reconstruction with autologous tissues or biologic materials resolved the presenting complaints in all cases.Conclusion: Bacterial biofilms should be considered an important contributor to the pathology and complications associated with prosthetic mesh implanted in the abdominal wall. If biofilms are present, complete removal of the mesh and repair of the resulting defect without alloplastic materials is an effective intervention<br/

Cutaneous fistula from the gastric remnant resulting from a chronic suture-associated biofilm infection

A 53-year-old woman developed three chronic draining sinuses after Roux-en-Y gastric bypass; these persisted for almost 1 year despite antibiotics and local wound care. At approximately 1 year post-operatively, the drainage from the most superior sinus increased significantly and assumed a greenish hue, prompting concerns for gastrocutaneous fistula despite negative radiologic evaluation. At surgery, the patient was found to have a retained permanent multifilament suture at the base of each sinus, with associated inflammatory and fibrous tissue and a “slimy” matrix. Confocal laser scanning microscopy of both the explanted sutures and investing soft tissue revealed extensive bacterial biofilm formation. Also at surgery, a frank fistulous track was noted communicating the most superior suture/sinus to the gastric remnant, necessitating laparotomy and remnant gastrectomy in addition to removal of the foreign bodies (sutures) and concomitant panniculectomy. The patient has subsequently been free of complaint or finding for over 3 year