Excision of Suspected Chronic Infected Suture Sinus

A 65-year-old female with a history of a left deep inferior epigastric perforator (DIEP) flap for breast reconstruction presented with an incisional hernia and a draining sinus tract overlying the site for her DIEP flap harvest confirmed on physical exam and cross-section imaging. She underwent a wound exploration where the entire suture sinus was excised, and we confirmed that there was no residual foreign material left in the area. This case highlights the importance of staged abdominal wall reconstruction and addressing chronic infection before proceeding with surgery.

Hernia repair; sinus tract; wounds; and injuries.

Complex ventral hernia defined by the Ventral Hernia Working Group (VHWG) include those with potential contamination or active infection.¹ These hernias represent a challenging entity in complex hernia repair as the risk of a post-hernia repair surgical site infection (SSI) or mesh infection substantially increases the risks of hernia recurrence. While there have been substantial advancements in hernia repair techniques that lead to favorable outcomes in contaminated hernia repair,^2–4 it is generally still strongly recommended to address reversible causes of contamination prior to proceeding with a definitive hernia repair.⁵

Chronic infected suture sinuses are chronic wound complications wherein a retained or non-degraded suture material creates a biofilm formation, foreign body reaction, chronic inflammation, and a sinus tract formation.^6,7 The exact incidence and mechanisms are unknown, but general risk factors include permanent sutures, braided sutures, and wound contamination.⁸ Treatment of a chronic suture sinus involves excision of the sinus tract and removal of any foreign body material, and this treatment will often resolve chronic SSIs.

We present a case of a patient with a complex ventral hernia and a chronic infected suture sinus. We present the first stage of their surgery with excision of their suture sinus.

The patient is an otherwise healthy 65-year-old female with a history of left breast cancer 15 years prior requiring a left mastectomy and autologous reconstruction with a left deep inferior epigastric perforator (DIEP) flap. The DIEP anterior fascial defect was closed with permanent braided polyester sutures. Over several years, she developed an abdominal bulge. She also developed a tender and inflamed bulge in the left lower quadrant after a minor trauma. An initial CT scan demonstrated multiple midline hernias, a left paramedian bulge, and a left posterior sheath defect all in keeping with a hernia that had developed after a left DIEP harvest. She also had a small inflammatory collection. This was suspected to be related to a tearing of her permanent suture off the fascia and surrounding structures during the traumatic event. This area was observed to allow the inflammation to settle. After 2 years, she continues to have an opening with chronic seropurulent drainage over where the inflammatory collection had occurred. Repeat imaging demonstrates a cavity draining to the skin level. Preoperative cultures grew commensal skin organisms without evidence of methicillin resistant staphylococcus aureus (MRSA) or other resistant organisms. Taken together, her presentation was in keeping with likely a chronic, possibly infected, suture sinus and she was consented for an excision of the suture sinus.

She is a non-smoker, has Type 1 diabetes with an HbA1C of 7.5, and is 77 kg, 170 cm tall, with a BMI of 26.6. She had been seen by her primary care providers for medical optimization of her diabetes for several months, and her HbA1C had plateaued at this level.

With the presence of a potentially infected sinus tract, this is a VHWG Grade 3 hernia. We proceeded with a staged approach to minimize the potential for active infection.

Her physical exam demonstrates multiple small hernias along the midline that are soft and reducible, as well as a large general left paramedian bulge along where her DIEP harvest was performed. She has a 5-mm sinus in the left lower quadrant draining serous fluid.

CT scan of the abdomen demonstrated multiple 1–4-cm hernias along the midline, a lower abdominal bulge as a result of muscle loss from her DIEP flap, and a chronic suture sinus which tracts from the skin down to the level of the fascia.

Chronic suture sinus tracts will often undergo cycles of periodic drainage, partial closure/healing, infection, and drainage. They can also persist as chronically draining tracts without substantial signs of infection. When associated with absorbable sutures, they may sometimes spontaneously resolve once the absorbable suture has completely dissolved; however, this is not always the case as mature sinus tract can continue to drain without any foreign body material.

Observation alone may lead to spontaneous resolution of chronic suture sinus tracts if they are associated with absorbable material once the foreign body material completely resolves. Limited courses of topical or oral antibiotics or incision & drainage can be helpful for superinfection and surrounding cellulitis. However, the vast majority of chronic suture sinus tracts are persistent and recurring and do not resolve without treatment.

In general, excision of the chronic suture sinus will resolve persistent draining or recurrent infections. In this specific instance of a chronic suture sinus with an associated hernia, the goal is to address all reversible sources prior to placing permanent synthetic mesh to reduce the risk of having wound or mesh contamination during the definitive hernia repair.

In this case of a chronic suture sinus with an associated ventral hernia, we performed an open excision of the sinus tract. To ensure complete excision of the sinus tract, we followed the fibrous capsule typically created by a sinus tract, and debrided this until we were left with healthy bleeding subcutaneous tissue. The chronic sinus tract was excised down to the level of the fascia, we confirmed that there was no evidence of mesh or permanent material, and the wound was closed in layers with ribbon gauze packing as a wick to drain any residual infection. The patient was discharged home the same day, and the gauze was removed in 24 hours. The wound completely healed without issue at 1-month follow up. She then went on to undergo a minimally invasive retromuscular mesh-based hernia repair 5 months after her excision of sinus tract with bilateral retrorectus dissection and left transversus abdominis release. She has since had follow-up 1 year after her initial sinus tract removal and 6 months from her hernia repair with no issues.

This case highlights the refractory nature of chronic suture sinus tracts and the need for operative excision to address this issue. As well, it demonstrates the important principle of addressing reversible sources of wound contamination prior to performing complex hernia repair.

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Dr. Fung has the following disclosures: speaker for Becton-Dickinson.

Dr. Pauli has the following disclosures: speaker for Becton-Dickinson and Medtronic, consultant for Boston Scientific Corp., Actuated Biomedical, Inc., Cook Biotech, Neptune Medical, Surgimatix, Noah Medical, Allergan, Intuitive Surgical, ERBE, Integra, Steris, Vicarious Surgical, Telabio and Mesh Suture Inc. He has royalties in UpToDate, Inc. and Springer and financial interests in IHC, Inc., Cranial Devices Inc, Actuated Medica.

The patient referred to in this video has given their informed consent to be filmed and is aware that information and images will be published online.